lattice
MOPC01
Study of interfering spin resonances in multi-snake lattice
29
Using a simplified multi spin resonances model we study the how the interference of spin resonances near a strong intrinsic spin resonance crossing effect the polarization transmission as a function of emittance for a lattice with more than two snakes.
Paper: MOPC01
DOI: reference for this paper: 10.18429/JACoW-IPAC2024-MOPC01
About: Received: 15 May 2024 — Revised: 18 May 2024 — Accepted: 19 May 2024 — Issue date: 01 Jul 2024
MOPC15
Study of the corrector systems for the new lattice of the CERN hadron-hadron Future Circular Collider
79
A new layout for the energy-frontier hadron collider (FCC-hh) under study at CERN has been designed, following the constraints imposed by the outcome of recent tunnel placement studies. The new lattice and the need to maximize the dipole filling factor triggered a deep revision of the corrector systems located in the regular arcs, such as orbit, tune, linear coupling, and chromaticity correctors. The system of octupoles aimed at providing Landau damping has also been reviewed. Furthermore, the corrector package in the experimental insertion aimed at compensating the field quality of the triplet quadrupoles has been reconsidered in view of the experience gained with the design of the corresponding system developed for the CERN HL-LHC. In this paper, an account of this review is presented and discussed in detail. These estimates will need confirmation when the magnet design of the various correctors will be studied.
Paper: MOPC15
DOI: reference for this paper: 10.18429/JACoW-IPAC2024-MOPC15
About: Received: 13 May 2024 — Revised: 19 May 2024 — Accepted: 19 May 2024 — Issue date: 01 Jul 2024
MOPC73
Design Updates to the EIC Electron Storage Ring Lattice
234
The Electron-Ion Collider (EIC) at Brookhaven National Laboratory will feature a 3.8-kilometer electron storage ring (ESR) that will circulate polarized beams with energies ranging from 5 to 18 GeV for collision with hadrons from a separate ring at luminosities up to 10^34 cm^{-2} s^{-1}. This contribution focuses on several recent changes to the lattice design of the ESR. Super-bend dipole triplets are used in the arc cells to increase the damping decrement and horizontal emittance at 5 GeV. Their lengths have recently been optimized to balance these two requirements. The interaction region has been modified to accommodate the requirements of a Compton polarimeter. Major changes have been made to IR8, which is the location of a possible second interaction region and detector that may be installed in a future upgrade. A design for a non-colliding IR8 has been developed that simplifies the setup to reduce initial costs and complexity. The latest lattice design of the ESR is presented here, and the major design choices are discussed.
Paper: MOPC73
DOI: reference for this paper: 10.18429/JACoW-IPAC2024-MOPC73
About: Received: 13 May 2024 — Revised: 18 May 2024 — Accepted: 18 May 2024 — Issue date: 01 Jul 2024
MOPC80
Global betatron coupling compensation for the hadron storage ring of the Electron-Ion Collider
258
The Electron Ion Collider (EIC), to be constructed at Brookhaven National Laboratory, will collide polarized high-energy electron beams with hadron beams, achieving luminosities up to 1e+34 cm^−2 s^−1 in the center-mass energy range of 20-140 GeV. The Hadron Storage Ring (HSR) of the EIC will utilize the arcs of the Relativistic Heavy Ion Collider (RHIC) and construct new straight sections connecting the arcs. In this article, we will examine all available skew quadrupoles currently in the HSR lattice and explore possible schemes for future global betatron coupling correction with RHIC-like decoupling feedback system. The effects of detector solenoids and quadrupole rolls are estimated at injection and stored energies. We also studied the decoupling requirements for generating and maintaining large transverse emittance ratio beams in the HSR.
Paper: MOPC80
DOI: reference for this paper: 10.18429/JACoW-IPAC2024-MOPC80
About: Received: 15 May 2024 — Revised: 20 May 2024 — Accepted: 23 May 2024 — Issue date: 01 Jul 2024
MOPC82
Dynamic aperture of the EIC electron storage ring
266
Design of the electron-ion collider (EIC) at Brookhaven National Laboratory continues to be optimized. Particularly, the collider storage ring lattices have been updated. Dynamic aperture of the evolving lattices must be kept sufficiently large, as required. In this paper, we discuss the collider Electron Storage Ring, where the lattice updates include improvements of the interaction region layout and arc dipole configuration, reduced number of magnet types, and changes related to the use of existing magnets. Optimization of non-linear chromaticity correction for an updated 18 GeV lattice and the latest estimates of dynamic aperture with errors are presented.
Paper: MOPC82
DOI: reference for this paper: 10.18429/JACoW-IPAC2024-MOPC82
About: Received: 16 May 2024 — Revised: 20 May 2024 — Accepted: 20 May 2024 — Issue date: 01 Jul 2024
MOPG01
Effects of the ALBA slab movement on ALBA-II
281
ALBA, the Spanish third generation synchrotron light source, is studying the future construction in the same location of a fourth generation light source called ALBA-II. Since the construction of ALBA in 2008, its critical slab has moved significantly, changing with it the accelerator elements positions. In this study, the effects on closed orbit and beam optics errors are simulated from data of the survey campaigns on the ALBA storage ring and compared to measurements in terms of orbit, linear optics, and orbit correctors budget. The results of this study on ALBA are used to infer the effect of the slab movement on the future machine through simulations, predicting yearly and seasonal changes. Plausible correction methods are discussed.
Paper: MOPG01
DOI: reference for this paper: 10.18429/JACoW-IPAC2024-MOPG01
About: Received: 13 May 2024 — Revised: 18 May 2024 — Accepted: 18 May 2024 — Issue date: 01 Jul 2024
MOPG02
An update on EIC rapid cycling synchrotron optics
285
The Electron-Ion Collider (EIC) requires continuous replacement of the stored electron bunches to facilitate arbitrary spin patterns in the Electron Storage Ring (ESR). This is accomplished by a dedicated, spin transparent Rapid Cycling Synchrotron (RCS). The dynamic range of the accelerator is from 400 MeV to 18 GeV. To maintain stability throughout the acceleration ramp, the linear and nonlinear optics must be tuned accordingly. In this paper, we will discuss the updated linear optics, chromaticities, and dynamic aperture of the RCS.
Paper: MOPG02
DOI: reference for this paper: 10.18429/JACoW-IPAC2024-MOPG02
About: Received: 15 May 2024 — Revised: 19 May 2024 — Accepted: 21 May 2024 — Issue date: 01 Jul 2024
MOPG03
Polarization performance of a 3 GeV electron booster
289
We study the design and spin performance of a polarized electron Booster. This booster will accelerate polarized electrons from 200 MeV to 3 GeV. We examine the polarization transmission of the existing NSLS-II Booster design as well as a modified AGS-Booster lattice using an 8-fold symmetric design and increasing the betatron tune to 7.85 to avoid all intrinsic spin resonances.
Paper: MOPG03
DOI: reference for this paper: 10.18429/JACoW-IPAC2024-MOPG03
About: Received: 14 May 2024 — Revised: 18 May 2024 — Accepted: 18 May 2024 — Issue date: 01 Jul 2024
MOPG05
Low-alpha operation of the IOTA storage ring
296
Operation with ultra-low momentum-compaction factor (alpha) is a desirable capability for many storage rings and synchrotron radiation sources. For example, low-alpha lattices are commonly used to produce picosecond bunches for the generation of coherent THz radiation and are the basis of a number of conceptual designs for EUV generation via steady-state microbunching (SSMB). Achieving ultra-low alpha requires not only a high-level of stability in the linear optics but also flexible control of higher-order compaction terms. Operation with lower momentum-compaction lattices has recently been investigated at the IOTA storage ring at Fermilab. Experimental results from some initial feasibility studies will be discussed in the context of ensuring an improved understanding of the IOTA optics for future research programs.
Paper: MOPG05
DOI: reference for this paper: 10.18429/JACoW-IPAC2024-MOPG05
About: Received: 24 May 2024 — Revised: 28 May 2024 — Accepted: 28 May 2024 — Issue date: 01 Jul 2024
MOPG07
Dispersion orbit detection by orbit harmonic analysis and potential applications
304
Electron storage rings in synchrotron light sources are typically composed of 𝑁 identical sectors that repeat over the ring. Transverse plane betatron frequencies are not an integer harmonic of the beam revolution frequency to avoid that accelerator imperfection effects are turn-by-turn amplified causing beam losses. Consequently, orbit variations induced by ring parameters not affecting beam energy, do not show periodicity equal to 𝑁, while variations affecting energy do generate dispersion orbits with 𝑁 periodicity. In the relativistic case, the beam energy in a ring is set by its closed orbit length (defined by the RF frequency) jointly with the field in bend magnets. Ring thermal expansion/compression causes energy variations and periodic dispersion orbits. In the frequency domain, the real-time amplitude of these orbits can be determined from their 𝑁 spectral line magnitude and phase. This info can be used in orbit feedbacks to adjust the RF to remove orbit dispersion components avoiding conflict with the corrector magnet action. Initial measurements performed at the Advanced Light Source in Berkeley to validate the technique are presented. Additional application possibilities are also discussed.
Paper: MOPG07
DOI: reference for this paper: 10.18429/JACoW-IPAC2024-MOPG07
About: Received: 14 May 2024 — Revised: 20 May 2024 — Accepted: 20 May 2024 — Issue date: 01 Jul 2024
MOPG08
Beam-based alignment simulations for the Future Circular Collider electron lattice
308
Parallel beam-based alignment (PBBA) techniques can be used to determine the magnetic centers for multiple magnets with simultaneous measurements and are much faster than traditional methods which target one magnet at a time. The PBBA techniques are very desirable for commissioning larger machines such as the Future Circular Collider (FCC). In this study, we applied PBBA techniques on quadrupoles and sextupole magnets for the FCC-ee lattice in simulations. Improvements to the PBBA techniques were made. It is shown that sub 10-micron accuracy for quadrupoles and sub 20-micro accuracy for sextupoles can be achieved.
Paper: MOPG08
DOI: reference for this paper: 10.18429/JACoW-IPAC2024-MOPG08
About: Received: 10 May 2024 — Revised: 20 May 2024 — Accepted: 20 May 2024 — Issue date: 01 Jul 2024
MOPR01
Lattice design of a pulsed synchrotron for a muon collider fitting within the Fermilab site boundary
448
A muon collider allows one to have a high energy reach for physics studies while having a relatively compact footprint. Ideally such a machine would accelerate muon beams to about 5 TeV. We present a preliminary lattice design for a pulsed synchrotron that will accelerate muon beams to their maximum collision energy and having a circumference of 16.5 km, which would allow it to fit just within the Fermilab site boundary. We wish to estimate the maximum energy that muons can be accelerated to on the Fermilab site based on a realistic lattice layout. To achieve a high average bend field, superconducting fixed field dipoles are interleaved with iron-dominated dipoles whose field is rapidly ramped from negative to positive field. Multiple RF stations are required to ensure that the beam energy and the dipole fields are reasonably well synchronized and to avoid longitudinal losses due to the large synchrotron tune. We use FODO arc cells with dispersion suppressed into the RF straights. We will discuss tradeoffs between maximum energy, energy range, and muon decays. We will consider whether to mix superconducting and iron quadrupoles like the dipoles.
Paper: MOPR01
DOI: reference for this paper: 10.18429/JACoW-IPAC2024-MOPR01
About: Received: 15 May 2024 — Revised: 22 May 2024 — Accepted: 22 May 2024 — Issue date: 01 Jul 2024
MOPR08
Current status of the FFA@CEBAF energy upgrade
474
An upgrade to the Continuous Electron Beam Accelerator Facility (CEBAF) at the Thomas Jefferson National Accelerator Facility (JLAB) to extend its energy reach from 12 GeV to 22 GeV is being explored. The upgrade pushes the boundaries of the current CEBAF facilities and will require several state-of-the-art beamline components. The first of which is nonscaling Fixed Field Alternating (FFA) Gradient recirculation arcs, using novel Halbach-style permanent magnets. These new arcs would replace the current highest-energy recirculating arcs and allow up to six new beam passes spanning approximately a factor of two in energy. Matching into these arcs will require the design of splitter bend systems proceeding the north and south linac sections. Matching from these arcs into the proceeding linac section will be achieved using a novel transition section. Additionally, several major changes to the existing CEBAF accelerator will be implemented including a 650 MeV recirculating injector, a new multi-pass linac optics design based on a triplet focusing lattice, and a newly designed spreader/recombiner bend systems to accommodate the higher energy requirement.
Paper: MOPR08
DOI: reference for this paper: 10.18429/JACoW-IPAC2024-MOPR08
About: Received: 15 May 2024 — Revised: 21 May 2024 — Accepted: 21 May 2024 — Issue date: 01 Jul 2024
MOPS03
Comprehensive modeling of Siberian Snakes in BNL’s AGS: symplectic tracking and optical compensation
686
Meaningful prediction and enhancement of spin-polarization in the RHIC/EIC accelerator complex relies on accurate modeling of each sub-component. Here we describe a symplectic field approximations of both Siberian Snakes in the AGS, enabling practical long-term tracking calculations. Without such symplectic representations, particle motion destabilizes very quickly close to injection energy. This optical instability manifests in $O(10^3)$ turns, and makes dynamic aperture smaller than realistic emittances. Combined with optimization using the Bmad toolkit, we implement steering and optical corrections of the snake effects at 80 distinct energies from injection to extraction, mimicking the measured lattice conditions at each energy. This process unveils unforeseen snake distortions of the vertical dispersion near injection energy, which are addressed. By interpolating between such optimized lattice configurations, Bmad's tracking capabilities allow advanced simulation of polarization transmission through the full AGS cycle.
Paper: MOPS03
DOI: reference for this paper: 10.18429/JACoW-IPAC2024-MOPS03
About: Received: 15 May 2024 — Revised: 19 May 2024 — Accepted: 19 May 2024 — Issue date: 01 Jul 2024
MOPS04
Proton polarization in RHIC with partial Siberian snakes
690
In December 2021, damage to a couple of RHIC power supplies forced one of two Siberian Snakes in the Blue ring to operate as a partial Siberian Snake and with a different snake axis of rotation. The time-averaged polarization for that run actually ended up higher than in the Yellow ring, after casting the undamaged snake as a partial snake as well. In this work, we simulate polarization transmission through a series of increasingly realistic models of the Blue ring in the “dangerous region” of polarization loss. At first the bare lattice has a perfect closed-orbit and ideal magnet strengths. Then the measured magnet-to-magnet field strength variations were added to the lattice. Finally, the six Interaction Region 5mm closed orbit bumps were implemented. Each of these model lattices compared the use of a pair of partial snakes against a pair of a full snakes, and in simulations with realistic emittances, realistic polarization losses were not reproducible without inclusion of nonzero RMS lattice misalignments.
Paper: MOPS04
DOI: reference for this paper: 10.18429/JACoW-IPAC2024-MOPS04
About: Received: 16 May 2024 — Revised: 18 May 2024 — Accepted: 18 May 2024 — Issue date: 01 Jul 2024
MOPS05
Explore higher order transverse resonance island buckets at the Cornell electron storage ring
694
Transverse resonance island buckets (TRIBs) near a third-order resonance are observed at the Cornell Electron Storage Ring with a newly-designed lattice. Hamiltonian perturbation theory and map-based PTC method have been successfully implemented to design the TRIBs lattice and find the fixed points near the third-order resonance. For even higher order resonances which are intrinsically weaker, the effects of radiation damping and excitation may not be negligible in the lepton machine such that the Hamiltonian approach could break down. In this paper, we study TRIBs near the fourth-order resonance with tracking simulations, which predict the existence of islands. Then experimental observations confirmed the islands formation near the fourth-order resonance. The positions of the fixed points extracted from experimental results agree reasonably well with those predictions from both tracking and PTC calculations. A unique method to push all particles into a single island is also demonstrated and discussed.
Paper: MOPS05
DOI: reference for this paper: 10.18429/JACoW-IPAC2024-MOPS05
About: Received: 14 May 2024 — Revised: 17 May 2024 — Accepted: 17 May 2024 — Issue date: 01 Jul 2024
MOPS09
Benchmark of AT vs MADX-PTC with exact integrators
709
Recently exact Hamiltonian integrators have been added for drift, multipoles and dipoles in Accelerator Toolbox. This paper reports the tracking simulations benchmarks performed to compare with the results provided by MADX-PTC for four lattices: FODO, DBA, H7BA and FCC-HFD@Z. Tracking times are also reported for completeness. The agreement in 4D is complete while small discrepancies persist for 6D tracking. Fringe fields models were not included in the comparison and are known to be different for the two codes.
Paper: MOPS09
DOI: reference for this paper: 10.18429/JACoW-IPAC2024-MOPS09
About: Received: 10 May 2024 — Revised: 23 May 2024 — Accepted: 23 May 2024 — Issue date: 01 Jul 2024
MOPS11
Dynamics study of the crab crossing at the electron ion collider using square matrix and iterative methods
717
Crab crossings are designed to increase the luminosity of accelerators by ensuring beam interactions are closer to a head on collision. One will be implemented at the Electron Ion Collider (EIC) at Brookhaven National Laboratory. It is then important to examine how the crab cavity will affect beam dynamics at the EIC. Methods such as Frequency Map Analysis (FMA) have been shown to be helpful in examining the phase space of accelerators in order to find properties such as resonances and the dynamic aperture. An alternative to such methods is an iterative method based on square matrix method that has been shown to reveal similar properties as FMA while reducing the computational power needed*,**. This method has been applied to the crab crossing scheme in order to find and explain effects of the higher order mode of crab cavities on the particle dynamics of the EIC.
Paper: MOPS11
DOI: reference for this paper: 10.18429/JACoW-IPAC2024-MOPS11
About: Received: 15 May 2024 — Revised: 22 May 2024 — Accepted: 23 May 2024 — Issue date: 01 Jul 2024
MOPS12
Axially symmetric e-lens based on McMillan map
721
In this work, we investigate the transverse dynamics of a single particle in a model integrable accelerator lattice, based on a McMillan axially symmetric electron lens. Although the McMillan e-lens has been considered as a device potentially capable of mitigating collective space charge forces, some of its fundamental properties have not been described yet. The main goal of our work is to close this gap and understand the limitations and potential of this device. We classify possible regimes with stable trajectories and provide set of canonical action-angle variables, along with an evaluation of the dynamical aperture, Poincar\'e rotation numbers as functions of amplitudes, and spread in nonlinear tunes.
Paper: MOPS12
DOI: reference for this paper: 10.18429/JACoW-IPAC2024-MOPS12
About: Received: 15 May 2024 — Revised: 17 May 2024 — Accepted: 17 May 2024 — Issue date: 01 Jul 2024
MOPS14
Comparison of Bayesian optimization and the reduction of resonance driving terms in the optimization of the dynamic aperture of the BESSY III MBA lattice
729
HZB is currently designing the lattice for BESSY III, the successor of the 1.7 GeV electron storage ring running in Berlin since 1998. HZB follows a deterministic lattice design strategy, where the natural substructures of a non-hybrid MBA lattice are optimized separately. The substructures consist of only a few parameters, that can be derived from the strategic goals of the project. In the next step, the focusing and de-focusing sextupole families are split up, to optimize the longitudinal and the transverse apertures. The paper compares two approaches to select the optimal sextupole strengths. The first one is multi-objective Bayesian optimization, where the dynamic aperture volume from tracking simulations is used as an objective to be maximized. The second approach does not involve tracking and minimizes the geometric and chromatic resonance driving terms. The comparison of the two results includes their quality in terms of the size of the achievable 3D dynamic aperture and the computational effort involved.
Paper: MOPS14
DOI: reference for this paper: 10.18429/JACoW-IPAC2024-MOPS14
About: Received: 15 May 2024 — Revised: 20 May 2024 — Accepted: 21 May 2024 — Issue date: 01 Jul 2024
MOPS15
Symplectic modeling of ALS-U bending dipoles using 3D magnetic field data
733
The Advanced Light Source Upgrade (ALS-U) is a 2 GeV high-brightness, nine-bend achromat storage ring, designed to reduce the natural emittance relative to the existing ALS by a factor of 20 for improved x-ray coherent flux and brightness. The upgrade includes the installation of an accumulator ring of the same energy as, and slightly smaller circumference than, the storage ring. The bending dipoles provide special challenges for accurate symplectic modeling, such as the combination of large sagitta and magnet narrow vertical aperture (in the accumulator ring) and overlapping fringe fields (in the main ring). We describe a procedure for the calculation of symplectic maps for the ALS-U dipoles using robust surface-fitting methods based on 3D finite-element field data, including a discussion of vector potential gauge choice and model-dependent effects on the lattice chromaticity.
Paper: MOPS15
DOI: reference for this paper: 10.18429/JACoW-IPAC2024-MOPS15
About: Received: 14 May 2024 — Revised: 21 May 2024 — Accepted: 21 May 2024 — Issue date: 01 Jul 2024
MOPS16
Optimizing the sextupole configuration for simultaneous correction of third order resonances at the recycler ring
736
For the Recycler Ring at Fermilab, space charge tune shifts of almost 0.1 will have to be dealt with under the Proton Improvement Plan (PIP-II) framework. This will lead to the excitation of third order resonances. The minimization of Resonance Driving Terms (RDTs) allows to mitigate the harmful effect of these betatron resonances. Past work has shown that previously-installed sextupoles can compensate the RDTs of individual third order resonance lines, thus reducing particle losses in these operational regimes. Nevertheless, trying to compensate multiple resonances of the same order simultaneously with these existing sextupoles is limited due to current constraints in the magnets. The following study showcases the procedure to install additional sextupoles in order to aid the compensation of multiple resonances. This includes the optimization of the new sextupoles' locations in order to cancel out multiple RDTs while minimizing the currents needed. This is followed by a verification of their effectiveness by means of the RDT response matrix.
Paper: MOPS16
DOI: reference for this paper: 10.18429/JACoW-IPAC2024-MOPS16
About: Received: 16 May 2024 — Revised: 21 May 2024 — Accepted: 23 May 2024 — Issue date: 01 Jul 2024
MOPS19
Tracking study of the bimodal RF cavity for storage ring light source
748
Beam lengthening is an effective and commonly used method to improving the beamlife of storage rings. Based on the previously proposed design of a room temperature conducting bimodal RF cavity, we conducted relevant dynamic simulations. Tracking study on a simulated storage ring lattice with the beam energy of 2 GeV and the synchronous radiation energy of 357 KeV, the results show that, the bimodal RF cavity which contains an accelerating field and a third harmonic field can effectively lengthen beam length, the beam lengthening effect similar to the double RF system which consists of main RF cavity and third harmonic cavity.
Paper: MOPS19
DOI: reference for this paper: 10.18429/JACoW-IPAC2024-MOPS19
About: Received: 15 May 2024 — Revised: 20 May 2024 — Accepted: 20 May 2024 — Issue date: 01 Jul 2024
MOPS20
Analysis of nonlinear deviation in a generalized longitudinal strong focusing unit
751
In a generalized longitudinal strong focusing (GLSF) approach employed in steady-state microbunching (SSMB) storage rings, the objective is to achieve complete cancellation of modulations by ensuring that a particle's longitudinal position remains unchanged after passing through both modulators. This requires effective control over the deviation in longitudinal position, which arises from lattice nonlinearities. This paper derives analytical formulations for the mean and standard deviation of the particle position deviation, expressed in terms of the beam and lattice-dependent parameters. The aim is to provide valuable insights into the system's behavior and enable optimization of the GLSF unit's performance.
Paper: MOPS20
DOI: reference for this paper: 10.18429/JACoW-IPAC2024-MOPS20
About: Received: 14 May 2024 — Revised: 17 May 2024 — Accepted: 18 May 2024 — Issue date: 01 Jul 2024
MOPS67
Experimental verification of integrability in a Danilov-Nagaitsev lattice using machine learning
878
In non-linear optics, achieving integrability can enhance the dynamic aperture in storage rings. We analyze turn-by-turn phase-space data from our Danilov-Nagaitsev lattice implementation at Fermilab's Integrable Optics Test Accelerator using machine learning. AI Poincaré estimates conserved quantities from experimental data without prior knowledge of the invariant structure, showing qualitative agreement with theoretical predictions. Additionally, one of the two learned invariants exhibits comparable or better conservation compared to known theoretical expressions.
Paper: MOPS67
DOI: reference for this paper: 10.18429/JACoW-IPAC2024-MOPS67
About: Received: 15 May 2024 — Revised: 23 May 2024 — Accepted: 23 May 2024 — Issue date: 01 Jul 2024
TUAD3
Simulation and study of the nuSTORM (neutrinos from Stored Muons) experiment
935
The nuSTORM experiment aims to create neutrino beams through muon decay in a storage ring, targeting %-level precision in flux determination. With access to two neutrino flavors, it enables precise measurement of nu-A cross sections and exhibits sensitivity to Beyond Standard Model (BSM) physics. With muons in the 1-6 GeV/c momentum range, it covers neutrino energy regimes relevant to experiments like DUNE and T2HK. Additionally, nuSTORM serves as a step towards a muon collider, a proof of concept for storage rings, and a test for beam monitoring and magnet technologies. The lattice structure consists of a pion transport line and a racetrack storage ring based on a hybrid FFA design, with conventional FODO cells in the production straight combined with FFA cells in the return straight and arcs. Using the nuSIM framework and BDSIM, this study simulates and optimizes the nuSTORM lattice, using beams from existing proton drivers. Using GENIE, neutrino events and their rates at the detector at different energies are also presented. The creation of synthetic neutrino beams like nuPRISM, allowing for >65% narrower neutrino beams than the natural muon decay spectrum is also discussed.
Paper: TUAD3
DOI: reference for this paper: 10.18429/JACoW-IPAC2024-TUAD3
About: Received: 15 May 2024 — Revised: 24 May 2024 — Accepted: 24 May 2024 — Issue date: 01 Jul 2024
TUCN1
Vertical beam halo characterisation at the ESRF EBS for operation with reduced in vacuum undulator gap
973
The vertical beam halo is the main limitation for very low gap operation of in-vacuum undulators at the ESRF EBS. The vertical halo is due to Touschek electrons with large energy deviation crossing some betatron resonances. The crossing of the resonances can transfer horizontal momentum to vertical momentum. The beam halo has been characterized and measured and different low halo optics have been studied and tested to allow the operation of the machine with lower in-vacuum undulator gaps.
Paper: TUCN1
DOI: reference for this paper: 10.18429/JACoW-IPAC2024-TUCN1
About: Received: 15 May 2024 — Revised: 20 May 2024 — Accepted: 20 May 2024 — Issue date: 01 Jul 2024
TUCN2
Machine learning for orbit steering in synchrotrons
977
In the latest years Machine Learning (ML) has seen an unprecedented diffusion in the most different fields in simulations and real life as well. Probably two of the first and most used ML applications in accelerators are the optimization of the final performance of the machines, and the so called virtual diagnostics. In the latest years ML was successfully applied to improve the machine safety performing fault detection or to prevent interlocks. In this work we explored the possibility to use a ML approach to efficiently steer the beam in case the lattice contains high order magnets (sextupolar order and higher). We applied this scheme to SLS 2.0, the synchrotron upgrading at the Paul Scherrer Institut.
Paper: TUCN2
DOI: reference for this paper: 10.18429/JACoW-IPAC2024-TUCN2
About: Received: 07 May 2024 — Revised: 17 May 2024 — Accepted: 17 May 2024 — Issue date: 01 Jul 2024
TUPC11
Advancements in the development of beam dynamics software APES for CEPC
1021
The design and study of the Circular Electron Positron Collider (CEPC) present a significant challenge, requiring the proper modeling of various physical phenomena such as the crab-waist collision scheme with a large Piwinski angle, strong nonlinear effects, energy sawtooth, beam-beam interactions, and machine impedances. In response to this challenge, the APES software project was proposed in 2021 and received support from the IHEP Innovative Fund in 2022. This paper provides an overview of the progress made in the APES project, encompassing modeling for special cases, orbital and spin tracking with synchrotron radiation, optics and emittance calculation, particle tracking, and more. Additionally, the paper discusses future developments.
Paper: TUPC11
DOI: reference for this paper: 10.18429/JACoW-IPAC2024-TUPC11
About: Received: 11 May 2024 — Revised: 20 May 2024 — Accepted: 23 May 2024 — Issue date: 01 Jul 2024
TUPC20
Simulating a 6D cooling channel in BDSIM
1050
Muon colliders hold promise for high luminosity multi-TeV collisions, without synchrotron radiation challenges. However, this involves investigation into novel methods of muon production, acceleration, cooling, storage, and detection. Thus, a cooling demonstrator has been proposed to investigate 6D muon ionization cooling. The MICE experiment validated ionization cooling to reduce transverse emittance. The demonstrator will extend this to also cool longitudinal emittance. It would also use bunched beams instead of single particles from a muon source. The 6D cooling lattice comprises successive cells which consist of: solenoids for tight focusing, dipoles to introduce dispersion in the beam, wedge-shaped absorbers for differential beam absorption, and RF cavities for reacceleration. In this paper, the simulation and further optimization of the rectilinear cooling channel is discussed. This analysis extends existing theoretical and numerical work using BDSIM, a Geant4-based accelerator framework built to simulate the transport and interaction of particles. The study also incorporates beams from existing proton drivers, using output from targetry and capture designs for the same.
Paper: TUPC20
DOI: reference for this paper: 10.18429/JACoW-IPAC2024-TUPC20
About: Received: 15 May 2024 — Revised: 22 May 2024 — Accepted: 24 May 2024 — Issue date: 01 Jul 2024
TUPC22
Optimisation of a permanent magnet multi-energy FFA arc for the CEBAF energy upgrade
1053
It is currently planned to increase the energy of the CEBAF recirculating linear accelerator to 20 GeV or more by adding two new recirculating arcs that contain multiple new energy passes. The beam is continuous (CW), so no field ramping is desired, making this a fixed-field accelerator (FFA). The wide energy range requires a low dispersion lattice that can be created with high-gradient permanent magnets. One constraint is the existing tunnel radius in relation to the fields achievable by practically-sized permanent magnets. Thus, searching for the most efficient implementation in terms of magnet material volume is important. In this paper, a lattice cell search and optimization is conducted that evaluates cells by the magnet volume per unit length, with the permanent magnet designs also produced via an automated code. The new lattice cells are compared to the previous manually designed cell.
Paper: TUPC22
DOI: reference for this paper: 10.18429/JACoW-IPAC2024-TUPC22
About: Received: 02 May 2024 — Revised: 18 May 2024 — Accepted: 18 May 2024 — Issue date: 01 Jul 2024
TUPC23
Beam correction for multi-pass arcs in FFA@CEBAF: status update
1057
This work examines the multi-pass steering of six electron beams in an FFA arc ranging from approximately 10.5 GeV to 22 GeV. Shown here is an algorithm based on singular value decomposition (SVD) to successfully steer all six beams through the arc given precise knowledge of all beam positions at each of one hundred and one diagnostic locations with one hundred individual corrector magnets: that is successive application of SVD to different 100 × 101 response matrices—one for each beam energy. Further, a machine learning scheme is developed which only requires knowledge of the energy-averaged beam position at each location to provide equivalent steering. Extension of this scheme to other beam optics quantities as well as transverse and longitudinal coupling is explored.
Paper: TUPC23
DOI: reference for this paper: 10.18429/JACoW-IPAC2024-TUPC23
About: Received: 15 May 2024 — Revised: 17 May 2024 — Accepted: 17 May 2024 — Issue date: 01 Jul 2024
TUPC24
Summary of Jefferson Lab LDRD on FFA@CEBAF beam dynamics simulations
1060
As Thomas Jefferson National Accelerator Facility (Jefferson Lab) looks toward the future, we are considering expanding our energy reach by using Fixed-Field Alternating Gradient (FFA) technology. Significant efforts have been made to design a hybrid accelerator which combines conventional recirculating electron LINAC design with permanent magnet-based FFA technology to increase the number of beam recirculations, and thus the energy. In an effort to further this progress, Jefferson Lab awarded a Laboratory Directed Research and Development (LDRD) grant to focus not on the design, but on detailed simulations of the designs created by the larger collaboration. This document will summarize the work performed during this LDRD, and direct the reader to other proceedings which describe elements of the work in greater detail.
Paper: TUPC24
DOI: reference for this paper: 10.18429/JACoW-IPAC2024-TUPC24
About: Received: 10 May 2024 — Revised: 21 May 2024 — Accepted: 22 May 2024 — Issue date: 01 Jul 2024
TUPC61
Applications of horizontal field damping wiggler in the diffraction limited storage ring
1136
In this study, we present a lattice design for the dif-fraction limited storage ring (DLSR), achieving an ultra-low natural emittance of 25.6 pm·rad (N-IBS). To address the significant intra-beam scattering (IBS) effect resulting from the ultra-low emittance and long damping times, Horizontal Field Damping Wigglers (HFDWs) have been adopted. These components de-crease damping times and beam horizontal emittance while generating vertical emittance, thereby achieving a "round beam" in the 864mDLSR. Using theoretical analysis and accelerator toolbox simulations, the op-timal peak field, period length, and overall length of the HFDWs for the 864mDLSR have been determined. In addition, the linear optical corrections were per-formed on both the front and rear units of the HFDWs using six quadrupoles.
Paper: TUPC61
DOI: reference for this paper: 10.18429/JACoW-IPAC2024-TUPC61
About: Received: 14 May 2024 — Revised: 16 May 2024 — Accepted: 17 May 2024 — Issue date: 01 Jul 2024
TUPG02
ALBA II accelerator upgrade project status
1220
ALBA is working on the upgrade project that shall transform the actual storage ring, in operation since 2012, into a 4th generation light source, in which the soft X-rays part of the spectrum shall be diffraction limited. The project was launched in 2021 with an R&D budget to build prototypes of the more critical components. The storage ring upgrade is based on a MBA lattice which has to comply with several constraints imposed by the decision of maintaining the same circumference (269 m), the same number of cells (16), the same beam energy (3 GeV), and as many of the source points as possible unperturbed. At present, the lattice optimization, iterating with the technical constraints of space and performance, is ongoing. This paper presents the status of the project, with the present proposed lattice, the proposed design for magnets, vacuum chambers and girders, the proposed RF system with fundamental and harmonics cavities, and the general context of the upgrade.
Paper: TUPG02
DOI: reference for this paper: 10.18429/JACoW-IPAC2024-TUPG02
About: Received: 15 May 2024 — Revised: 21 May 2024 — Accepted: 24 May 2024 — Issue date: 01 Jul 2024
TUPG09
Conceptual design of a future Australian light source
1236
Conceptual design work is under way for a fourth generation light source in Australia.This new light source is being designed as a completely new facility, intended to come into operation around 2037 as the current Third generation Australian Synchrotron reaches its end of life. Previous design work was done to consider a 600 m ring, but on review the decision was made to reduce the circumference to 450 m. This paper will outline the main design considerations, initial lattice design and technology choices currently under consideration.
Paper: TUPG09
DOI: reference for this paper: 10.18429/JACoW-IPAC2024-TUPG09
About: Received: 16 May 2024 — Revised: 22 May 2024 — Accepted: 22 May 2024 — Issue date: 01 Jul 2024
TUPG10
Preliminary lattice design for Australian Synchrotron 2.0
1239
A new project is underway to develop the successor to the current Australian Synchrotron. The new storage ring is proposed to be 455 m in circumference operating at 3 GeV. A preliminary 7BA lattice has been designed which utilizes the higher-order achromat (HOA) scheme to suppress strong sextupole driving terms. The lattice has 24 sectors and a natural horizontal emittance of 50 pm-rad. This is achieved using a combination of strong combined function magnets and reverse bending magnets in the unit cell, as well as careful tuning of the bending angles to preserve positive momentum compaction factor. The dynamic aperture, momentum aperture and Touschek lifetime have been optimized by tuning the linear optics and sextupole strengths with a multi-objective genetic algorithm.
Paper: TUPG10
DOI: reference for this paper: 10.18429/JACoW-IPAC2024-TUPG10
About: Received: 15 May 2024 — Revised: 22 May 2024 — Accepted: 22 May 2024 — Issue date: 01 Jul 2024
TUPG20
Numerical optimization of the Diamond-II storage ring optics
1254
The design performance of the 3.5 GeV Diamond-II low-emittance electron storage ring has been studied as a function of the linear and nonlinear lattice tuning parameters. An alternative working point has been identified which optimizes the beam lifetime and the injection efficiency for off-axis injection. The simulations include misalignment and field strength errors, with the number of machine seeds tuned to achieve converging results whilst minimizing computational time. The optimization takes care to preserve the design beam emittance, energy spread, Twiss parameters and cell tunes. The results are presented for 2D parameter scans and exploring the null space of the chromaticity response matrix.
Paper: TUPG20
DOI: reference for this paper: 10.18429/JACoW-IPAC2024-TUPG20
About: Received: 15 May 2024 — Revised: 19 May 2024 — Accepted: 19 May 2024 — Issue date: 01 Jul 2024
TUPG21
Further investigations into the impacts of insertion devices on the Diamond-II lattice
1258
As part of the Diamond-II upgrade project*, the Diamond storage ring will be replaced with a new modified hybrid 6 bend achromat (M-H6BA) lattice, in which each existing arc sections will be split in two to provide additional mid-straights and thereby increase the ring capacity. The majority of insertion devices currently in operation will be either retained or upgraded, and the new mid-straights allow the total number of ID beamlines to be increased from 28 to 36. Therefore, it is important to investigate how the IDs will affect the equilibrium emittance and energy spread, along with their impact on the linear and nonlinear beam dynamics. Methods to compensate for their effects have been established, including a re-optimization of the octupole settings and identification of alternative working points. A kickmap approach has been used to model all IDs, including the APPLE-II IDs and APPLE-II-Knot with active shim wires. In this paper, the outcome of these investigations will be presented and discussed.
Paper: TUPG21
DOI: reference for this paper: 10.18429/JACoW-IPAC2024-TUPG21
About: Received: 08 May 2024 — Revised: 19 May 2024 — Accepted: 19 May 2024 — Issue date: 01 Jul 2024
TUPG22
Full simulations of the Diamond-II storage ring commissioning and possible improvements of procedures
1262
To provide confidence in the future commissioning of the Diamond-II storage ring, realistic specifications for the error tolerances have been established. Based on these values, commissioning simulations have been conducted starting from on-axis injection through to stored beam and finally the alleviation of beta-beating caused by insertion devices. The goal of these studies is to develop a robust commissioning procedure that stays within the magnet strength limits using the statistics of many random machines simulated. In this paper we summarize these studies and present the results at each stage. Other topics such as testing on Diamond and comparisons of alternative commissioning methods are also discussed.
Paper: TUPG22
DOI: reference for this paper: 10.18429/JACoW-IPAC2024-TUPG22
About: Received: 14 May 2024 — Revised: 18 May 2024 — Accepted: 18 May 2024 — Issue date: 01 Jul 2024
TUPG27
Parallel beam-based alignment for the EBS storage ring
1278
The parallel beam based alignment technique developped at SLAC is applied for the EBS storage ring. The results are compared with the standard beam based alignment technique used for operation.
Paper: TUPG27
DOI: reference for this paper: 10.18429/JACoW-IPAC2024-TUPG27
About: Received: 10 May 2024 — Revised: 16 May 2024 — Accepted: 16 May 2024 — Issue date: 01 Jul 2024
TUPG28
BESSY III overview and its bending sources
1282
The BESSY III project evolves from a pre-CDR phase into the CDR phase. And for lattice design, it means, that one of the different Higher-Order-Achromat MBA lattice candidates has to be chosen as the baseline lattice for the iterations with the construction department. Therefore it is essential that the design of the main and most important components, the bending magnets, will be defined as early as possible. At BESSY III, it is requested, that the bends be used as bending sources in different regimes, the soft-X-ray (<2 keV), in the tender (2-12 keV), and hard X-rays (>10 keV). In this contribution, we will give an overview of the BESSY III project and its bending sources and discuss briefly the baseline lattice.
Paper: TUPG28
DOI: reference for this paper: 10.18429/JACoW-IPAC2024-TUPG28
About: Received: 15 May 2024 — Revised: 23 May 2024 — Accepted: 24 May 2024 — Issue date: 01 Jul 2024
TUPG36
Beam-based girder alignment to reduce corrector strengths: conceptual simulations for PETRA IV
1305
DESY is planning to upgrade PETRA III to a 4th generation light source. The magnetic lattice components are pre-installed and aligned on long girders before being installed in the tunnel. These long girders and the misalignment of the magnets pose a challenge for the PETRA IV lattice, including the storage of the beam in the ring. Commissioning simulations have been performed which showed that relatively high corrector strengths are required for the orbit correction system. A simulation study was performed to demonstrate the possibility of beam-based girder alignment correction to relax the corrector strengths during machine operation. The simulation results are presented and then discussed for later implementation.
Paper: TUPG36
DOI: reference for this paper: 10.18429/JACoW-IPAC2024-TUPG36
About: Received: 15 May 2024 — Revised: 17 May 2024 — Accepted: 17 May 2024 — Issue date: 01 Jul 2024
TUPG38
Design and construction progress of ALS-U
1313
The ALS-U project to upgrade the Advanced Light Source to a multi bend achromat lattice received CD-3 approval in 2022 marking the start of the construction phase for the Storage Ring. Construction of the accumulator under a prior CD-3A authorization is already well advanced. ALS-U promises to deliver diffraction limited performance in the soft x-ray range by lowering the horizontal emittance to about 70 pm rad resulting in two orders of magnitude brightness increase for soft x-rays compared to the current ALS. The design utilizes a nine bend achromat lattice, with reverse bending magnets and on-axis swap-out injection utilizing an accumulator ring. It is optimized to produce intense beams of soft x-rays, which offer spectroscopic contrast, nanometer-scale resolution, and broad temporal sensitivity. This paper presents the final design, prototype results as well as construction progress.
Paper: TUPG38
DOI: reference for this paper: 10.18429/JACoW-IPAC2024-TUPG38
About: Received: 21 May 2024 — Revised: 21 May 2024 — Accepted: 22 May 2024 — Issue date: 01 Jul 2024
TUPG39
Improve the injection with high energy for CAMD light source
1317
With Insertion devices adapted to Center of Advanced Microstructures and Devices (CAMD) light source. Injection has more difficulties at low energy. We have proposed some upgrade to the facility, but we would like to look for other choices. In the paper, we will mention the CAMD operation status, discuss raising electron energy method for injection, and simulate the transfer line. The practical upgrade will be proposed. The injection lattice at high electron energy will be available. The kicker parameter will be given.
Paper: TUPG39
DOI: reference for this paper: 10.18429/JACoW-IPAC2024-TUPG39
About: Received: 14 May 2024 — Revised: 20 May 2024 — Accepted: 21 May 2024 — Issue date: 01 Jul 2024
TUPG41
Study of an upgraded lattice for Taiwan Photon Source
1324
In pursuit of maximizing the performance of the Taiwan Photon Source (TPS), we conducted a feasibility study aimed at reassessing and optimizing the lattice configuration within the existing tunnel infrastructure. One of our main objective is to minimize displacement of source points for insertion devices (IDs) while augmenting overall beam performance. To achieve this, we propose an upgraded lattice design based on the multi-bend achromatic (MBA) scheme, featuring 5 bending achromat (5BA) in each arc. This report discusses the challenges encountered and presents preliminary results regarding the implementation of this 5BA lattice design.
Paper: TUPG41
DOI: reference for this paper: 10.18429/JACoW-IPAC2024-TUPG41
About: Received: 13 May 2024 — Revised: 16 May 2024 — Accepted: 16 May 2024 — Issue date: 01 Jul 2024
TUPG46
Error analysis and commissioning simulations for the SSRF-U lattice
1342
SSRF-U, a 3.0 GeV diffraction limited storage ring lattice with emittance of 53.2 pm∙rad, is an alternative to SSRF for future upgrades. A large number of high-field intensity and multi-function magnets are used in this compact lattice, which greatly increases the error sensitivity to the beam. To quickly complete beam commissioning and achieve stable operation in the future, error analysis and commissioning simulations were studied during the design phase. In this paper, we present commissioning simulations for the SSRF-U and analyze the lattice error acceptance depending on the simulation results at each stage.
Paper: TUPG46
DOI: reference for this paper: 10.18429/JACoW-IPAC2024-TUPG46
About: Received: 14 May 2024 — Revised: 20 May 2024 — Accepted: 20 May 2024 — Issue date: 01 Jul 2024
TUPG47
TDR baseline lattice for SOLEIL II upgrade project
1346
Previous TDR (Technical Design Report) studies for the SOLEIL upgrade project (SOLEIL II) have converged towards a lattice alternating 7BA and 4BA HOA (High Order Achromat) type cells providing an ultra low natural horizontal emittance value in the 85 pm·rad range at an energy of 2.75 GeV. The new TDR lattice is an evolution that keep the insertion devices photon source points at their present location, allows a better relative magnet positioning and more space for accommodating photon absorbers, BPMs (Beam Position Monitor) and other mandatory diagnostics. This last evolution includes a better modeling of all the bend magnets based on their realistic field profiles and the accommodation of height super-bends for beam-lines as well as for beam size diagnostics. In addition an exhaustive investigation of the systematic and especially the cross-talk multipoles as well as the phase 1 portfolio of insertion devices impacts has been carried out. This paper reports the linear and the non-linear beam dynamic optimizations as well as future directions for performance improvement.
Paper: TUPG47
DOI: reference for this paper: 10.18429/JACoW-IPAC2024-TUPG47
About: Received: 16 May 2024 — Revised: 22 May 2024 — Accepted: 23 May 2024 — Issue date: 01 Jul 2024
TUPR40
Development of prototype magnets for the ultralow emittance storage ring ALBA II
1502
The ALBA synchrotron light source is in the process of a significant upgrade, aiming to become a fourth-generation facility by reducing its emittance by at least 20 times. The initial phase of this project involves a comprehensive prototyping program designed to validate various critical technologies, such as magnets, vacuum systems, girders, etc., essential for facilitating the impending upgrade. This paper focuses on the development of the prototype magnets to implement the MBA lattice designed by our Beam Dynamics group. The lattice presents unique challenges, notably a remarkable degree of compactness necessitating magnet-to-magnet distances of just a few centimeters. Additionally, stringent strength requirements are imposed on both the quadrupolar (up to 110 T/m) and the sextupolar (up to 5000 T/m²) magnets. In this paper we will describe the design details of the initial set of resistive-type prototypes, as well as the preliminary efforts to develop alternative designs making use of permanent magnets. This dual-track approach reflects our dedication to both conventional methods and innovative solutions for the upgraded storage ring.
Paper: TUPR40
DOI: reference for this paper: 10.18429/JACoW-IPAC2024-TUPR40
About: Received: 15 May 2024 — Revised: 18 May 2024 — Accepted: 18 May 2024 — Issue date: 01 Jul 2024
TUPR48
Sextupole misalignment and defect identification and remediation in IOTA
1527
The nonlinear integrable optics studies at the integrable optics test accelerator (IOTA) demand fine control of the chromaticity using sextupole magnets. During the last experimental run undesirable misalignments and multipole composition in some sextupole magnets impacted operations. This report outlines the beam-based methods used to identify the nature of the misalignments and defects, and the subsequent magnetic measurements and remediation of the magnets for future runs.
Paper: TUPR48
DOI: reference for this paper: 10.18429/JACoW-IPAC2024-TUPR48
About: Received: 15 May 2024 — Revised: 22 May 2024 — Accepted: 22 May 2024 — Issue date: 01 Jul 2024
TUPR51
Design of permanent dipole magnet in transport line for TPS
1537
To reduce the electric power consumption and advance the magnetic stability, a prototype of BTS dipole magnet in TPS transfer line between booster and storage ring came into sight. An 1 m long, high current dipole will be replaced by a permanent magnet with Sm2Co17. The new permanent dipole magnet will decrease total volume compared with original electric one, and the homogeneity of integral field is promoted as well. With simulation, the assembly deviation was also discussed. This article presents the magnet circuit design status of prototype to upgrade the transport line in TPS.
Paper: TUPR51
DOI: reference for this paper: 10.18429/JACoW-IPAC2024-TUPR51
About: Received: 14 May 2024 — Revised: 16 May 2024 — Accepted: 17 May 2024 — Issue date: 01 Jul 2024
TUPS05
Simulations of polarized helions in the HSR
1634
The Electron Ion Collider calls for collisions of helion beam on polarized electron beams. Polarized helions will be injected into the Hadron Storage Ring at |Gγ| = 49.5 and have a maximum energy corresponding to |Gγ| = 820. Simulations of helions in this energy range have been performed using zgoubi. These studies quantify the polarization transmission with six snakes and also categorize the lattice constraints.
Paper: TUPS05
DOI: reference for this paper: 10.18429/JACoW-IPAC2024-TUPS05
About: Received: 15 May 2024 — Revised: 21 May 2024 — Accepted: 21 May 2024 — Issue date: 01 Jul 2024
TUPS28
Linac_Gen: integrating machine learning and particle-in-cell methods for enhanced beam dynamics at Fermilab
1695
Here, we introduce Linac_Gen, a tool developed at Fermilab, which combines machine learning algorithms with Particle-in-Cell methods to advance beam dynamics in linacs. Linac_Gen employs techniques such as Random Forest, Genetic Algorithms, Support Vector Machines, and Neural Networks, achieving a tenfold increase in speed for phase-space matching in Linacs over traditional methods, through the use of genetic algorithms. Crucially, Linac_Gen's adept handling of 3D field maps elevates the precision and realism in simulating beam instabilities and resonances, marking a key advancement in the field. Benchmarked against established codes, Linac_Gen demonstrates not only improved efficiency and precision in beam dynamics studies but also in the design and optimization of Linac systems, as evidenced in its application to Fermilab's PIP-II Linac project. This work represents a notable advancement in accelerator physics, marrying ML with PIC methods to set new standards for efficiency and accuracy in accelerator design and research. Linac_Gen exemplifies a novel approach in accelerator technology, offering substantial improvements in both theoretical and practical aspects of beam dynamics.
Paper: TUPS28
DOI: reference for this paper: 10.18429/JACoW-IPAC2024-TUPS28
About: Received: 21 May 2024 — Revised: 21 May 2024 — Accepted: 22 May 2024 — Issue date: 01 Jul 2024
TUPS33
Snake matching the EIC's hadron storage ring
1714
Pairs of Siberian Snakes allow the avoidance of first-order spin resonances during energy ramping. However, a high density of first-order resonances correlates with the presence of higher-order resonances after the installation of snakes. Thus, one effective tactic of mitigating higher-order resonances is by weakening the surrounding first-order ones, equivalent to minimizing the spin-orbit coupling integrals. Such a proxy helps sidestep a multi-hour polarization transmission simulation for each lattice configuration. In a three-fold super-periodic ring, using 12 snakes is a sufficient condition for completely eliminating the spin-orbit coupling integrals at all energies and tunes. Since the HSR will only have up to 6 snakes, we opt to focus on suppressing the strongest first-order resonances instead of the whole spectrum. By varying the snake reflection axes and the betatron phase advance in two of the arcs, we search in a 7-dimensional lattice space for the weakest resonance structure using a variety of metrics and find the configuration with highest polarization transmission.
Paper: TUPS33
DOI: reference for this paper: 10.18429/JACoW-IPAC2024-TUPS33
About: Received: 15 May 2024 — Revised: 20 May 2024 — Accepted: 23 May 2024 — Issue date: 01 Jul 2024
TUPS75
Orbit response matrix correction based on exploration enhanced evolutionary algorithm
1854
For a large ring, the response matrix contains tens of thousands of data points, allowing for a comprehensive representation of the ring’s linear optics. However, when it comes to fourth-generation diffraction-limited rings that utilize strong sextupoles and octupoles, the response matrix derived from closed orbit tracking is significantly influenced by nonlinearity. This nonlinearity poses challenges for the Linear Optics from Closed Orbit (LOCO) method in terms of matching lattice parameters and correcting lattice errors. In this study, we propose the utilization of an evolutionary algorithm that integrates multiple techniques to enhance exploration capabilities. By this, we aim to find the global optimal solution, which can effectively address the issues associated with the response matrix correction and achieve a larger dynamic aperture compared to the linear LOCO approach.
Paper: TUPS75
DOI: reference for this paper: 10.18429/JACoW-IPAC2024-TUPS75
About: Received: 08 May 2024 — Revised: 19 May 2024 — Accepted: 24 May 2024 — Issue date: 01 Jul 2024
WEPC27
Implementing NOECO at NSLS-II
2030
With the recently implemented lattice tool LOCOM, which combines the precision of LOCO as well as the speed of multi-frequency AC-LOCO, it takes only a few minutes for the NSLS-II lattice measurement and correction of both linear optics and coupling. Besides, LOCOM can be applied to characterize linear optics at the extremely high chromaticity condition, thus, greatly speeding up the development of a new operational mode with x/y chromaticity of +10/+10. The high chromaticity lattice could potentially enable a reliable operation of the storage ring with high single-bunch current. Moreover, to characterize the errors of chromatic sextupoles with high precision, we are in the process of implementing the NOECO based on the LOCOM method. Preliminary simulation study indicates that 1-2% precision can be achieved for the calibration of chromatic sextupole errors. If such high accuracy can be achieved, it could potentially help in resolving some long-standing challenges of NSLS-II, e.g., the discrepancy between the designed and measured tune shift with amplitude. Finally, to have an independent crosscheck, we have implemented the TBT based ICA NOECO method with a confirmed 2% accuracy.
Paper: WEPC27
DOI: reference for this paper: 10.18429/JACoW-IPAC2024-WEPC27
About: Received: 13 May 2024 — Revised: 17 May 2024 — Accepted: 17 May 2024 — Issue date: 01 Jul 2024
WEPC37
Nonlinear optimization for the HLS-II storage ring
2040
Hefei Light Source (HLS) is a small and compact synchrotron light source with an electron beam energy of 800 MeV and a circumference of 66.13 m. The storage ring lattice adopts the Double-Bend Achromat (DBA) structure with 4 super periods. Considering the future upgrade of the injection system by using a nonlinear kicker (NLK), we optimize the dynamic performance of the storage ring. The optimization mainly aims at increase the dynamic aperture and beam lifetime, which helps improve the injection efficiency for the new injection scheme. While keeping the current layout of the lattice, the linear optics is also modified in order to improve its nonlinear performance. In this paper, we represent our work on the optimization of the HLS-II storage ring.
Paper: WEPC37
DOI: reference for this paper: 10.18429/JACoW-IPAC2024-WEPC37
About: Received: 15 May 2024 — Revised: 24 May 2024 — Accepted: 24 May 2024 — Issue date: 01 Jul 2024
WEPC38
Commissioning simulation for the HALF storage ring
2043
Hefei advanced light facility (HALF) is a fourth-generation light source under construction. Its storage ring is a diffraction-limited one with an energy of 2.2 GeV and an extremely low emittance of less than 100 pm·rad. The real storage ring is different from the ideal lattice due to various kinds of errors. Those errors come from many sources, like misalignment of components, imperfect magnetic fields, RF cavity, etc. Due to the strong nonlinear nature and small dynamic aperture of the HALF storage ring, those errors significantly increase the difficulty of its commissioning. To figure out the practical performance of the lattice with those errors, a start-to-end commission simulation is performed in this study, which also helps to generate effective commissioning process for the HALF storage ring.
Paper: WEPC38
DOI: reference for this paper: 10.18429/JACoW-IPAC2024-WEPC38
About: Received: 15 May 2024 — Revised: 17 May 2024 — Accepted: 17 May 2024 — Issue date: 01 Jul 2024
WEPC47
First Steps Toward Molecular beam epitaxial growth of potassium antimonide photocathodes
2068
Molecular-beam epitaxy (MBE) growth with lattice-matched substrates can lead to the synthesis of single-crystal alkali antimonide photocathodes[1]. Single-crystal photocathodes are expected to have not only high quantum efficiencies (QE) but also low mean transverse energy since they are usually grown as thin films. In this proceeding, we report the synthesis of potassium antimonide photocathodes at the PHOtocathode Epitaxy Beam Experiments (PHOEBE) laboratory at Cornell via MBE by using a sequence of shuttered growth of different unit cells. These cathodes are characterized in terms of spectral response and crystalline structure. The RHEED pattern acquired while synthesizing these photocathodes indicates epitaxial growth occurring on both SiC and Si(100) substrates. Oxidation studies were also performed to better understand the robustness of these materials under non-ideal ultra-high vacuum (UHV) conditions.
Paper: WEPC47
DOI: reference for this paper: 10.18429/JACoW-IPAC2024-WEPC47
About: Received: 15 May 2024 — Revised: 21 May 2024 — Accepted: 21 May 2024 — Issue date: 01 Jul 2024
WEPG65
MENT-Flow: maximum-entropy phase space tomography using normalizing flows
2375
Generative models can be trained to reproduce low-dimensional projections of high-dimensional phase space distributions. Normalizing flows are generative models that parameterize invertible transformations, allowing exact probability density evaluation and sampling. Consequently, flows are unbiased entropy estimators and could be used to solve the high-dimensional maximum-entropy tomography (MENT) problem. In this work, we evaluate a flow-based MENT solver (MENT-Flow) against exact maximum-entropy solutions and Minerbo's iterative MENT algorithm in two dimensions.
Paper: WEPG65
DOI: reference for this paper: 10.18429/JACoW-IPAC2024-WEPG65
About: Received: 15 May 2024 — Revised: 17 May 2024 — Accepted: 17 May 2024 — Issue date: 01 Jul 2024
WEPR02
The status of the FCC-ee optics tuning
2449
With a circumference of approximately 91 km, the Future Circular electron-positron Collider, FCC-ee, aims for unprecedented luminosities at beam energies from 45.6 to 182.5 GeV. A major challenge is reaching its design performance in the presence of magnet misalignments and field errors. The FCC-ee optics tuning working group studies all related aspects, and applies state-of-the-art techniques for beam-based alignment, commissioning simulations, beam threading, optics measurements and corrections, which are probed at numerous world-leading accelerator physics facilities. Advanced optics correction simulations include interaction-point tuning, magnetic tolerances are studied, and a new optics is under scrutiny. The current status of tuning simulations for different FCC-ee lattices is presented.
Paper: WEPR02
DOI: reference for this paper: 10.18429/JACoW-IPAC2024-WEPR02
About: Received: 15 May 2024 — Revised: 22 May 2024 — Accepted: 23 May 2024 — Issue date: 01 Jul 2024
WEPR03
Simulated performance of FCC-ee IP tuning knobs
2453
The Future Circular electron-positron Collider (FCC-ee) is a proposed accelerator with 91 kilometres circumference that should serve as a Higgs and electroweak factory, with unprecedented luminosity. Unavoidable misalignments and field errors will generate optics errors at the interaction point (IP), whose effect will be amplified by the beam-beam collisions, which will make it challenging for the collider to reach its intended luminosity goals. Hence, there is a need for correction tools that will enable the precise correction of the optics at the IP, such as linear coupling parameters and spurious dispersion. This will be essential both for FCC-ee commissioning and during routine operation. This paper describes the construction, simulated effectiveness, and constraints of IP tuning tools.
Paper: WEPR03
DOI: reference for this paper: 10.18429/JACoW-IPAC2024-WEPR03
About: Received: 13 May 2024 — Revised: 23 May 2024 — Accepted: 24 May 2024 — Issue date: 01 Jul 2024
WEPR04
Relaxed insertion region optics and linear tuning knobs for the Future Circular Collider
2457
This paper provides updates on two essential toolsets designed to facilitate the tuning and commissioning processes of the Future Circular Collider (FCC): relaxed optics and linear tuning knobs specifically for the experimental insertion regions. Motivated by the imperative need for efficient tuning strategies, we outline the construction methodology for both toolsets and present initial studies demonstrating their efficacy. The paper discusses the significance of these tools in enhancing the operational capabilities of the FCC and presents early results showcasing their potential impact on the collider's performance during tuning and commissioning phase.
Paper: WEPR04
DOI: reference for this paper: 10.18429/JACoW-IPAC2024-WEPR04
About: Received: 15 May 2024 — Revised: 21 May 2024 — Accepted: 22 May 2024 — Issue date: 01 Jul 2024
WEPR05
Benchmarking equilibrium emittance simulation tools for the Future Circular Collider
2461
The determination of equilibrium emittance stands as a critical factor in optimizing the luminosity of the Future Circular Collider (FCC). In order to have accurate simulations and understanding of the emittance, multiple effects have to be taken into consideration including errors in the machine, solenoid effects, synchrotron radiation and beam-beam effects. The novel X-Suite software aims to encompass many of these effects. In this paper we present benchmark studies and first results for determining equilibrium emittances using X-Suite and other simulation codes.
Paper: WEPR05
DOI: reference for this paper: 10.18429/JACoW-IPAC2024-WEPR05
About: Received: 15 May 2024 — Revised: 22 May 2024 — Accepted: 23 May 2024 — Issue date: 01 Jul 2024
WEPR06
Lattice correction and polarization estimation for the Future Circular Collider e+e-
2465
Precise determination of the center-of-mass energy in the Future Circular Collider e+e- (FCC-ee) at Z and W energies can be achieved by employing resonant spin depolarization techniques, for which a sufficient level of transverse beam polarization is demanded under the presence of machine imperfections. In this study, the FCC-ee lattice has been modeled and simulated with a variety of realistic lattice imperfections, including misalignments, angular deviations, BPM errors, long-range errors, etc., along with refined orbit correction and tune matching procedures. The equilibrium polarization is calculated within the context of realistic machine models, aiming to understand the underlying reason for polarization loss and potentially improve polarization by lattice manipulation.
Paper: WEPR06
DOI: reference for this paper: 10.18429/JACoW-IPAC2024-WEPR06
About: Received: 15 May 2024 — Revised: 28 May 2024 — Accepted: 28 May 2024 — Issue date: 01 Jul 2024
WEPR10
First FCC-ee lattice designs with Nested Magnets
2477
The Future Circular Electron-Positron Collider (FCC-ee) represents a cutting-edge particle physics facility designed to further investigate the Z, W± and Higgs boson in addition to the top quark. The implementation of Nested Magnets (NMs) in the FCC-ee arc cells would maintain high luminosity and reduce its energy consumption. The use of these special magnets induces changes in the damping partition numbers. To mitigate this the dipole fields in focusing and defocusing quadrupoles have to be different. This solution gives rise to incompatibility problems for the machine layout between the different energy configurations as the optics is also changed. This problem is tackled by defining different bending and geometric angles for the NMs. The beam dynamics and performance aspects of the new lattice are studied in this paper.
Paper: WEPR10
DOI: reference for this paper: 10.18429/JACoW-IPAC2024-WEPR10
About: Received: 15 May 2024 — Revised: 20 May 2024 — Accepted: 21 May 2024 — Issue date: 01 Jul 2024
WEPR11
Parameter space for the magnetic design of Nested Magnets in the FCC-ee arc cell
2481
The Future Circular Collider (FCC-ee) is designed to explore the Z and W± bosons, along with the Higgs boson and top quark, achieving exceptionally high luminosity. In order to minimize the energy lost per turn due to Synchrotron Radiation (SR) we explore the use of Nested Magnets (NMs) into the arcs cell. For this, it is necessary to explore the possible combinations of the different magnet types in the cell, namely: dipoles, quadrupoles and sextupoles. Specifications in terms of strength and alignment tolerances are reviewed in this paper.
Paper: WEPR11
DOI: reference for this paper: 10.18429/JACoW-IPAC2024-WEPR11
About: Received: 15 May 2024 — Revised: 23 May 2024 — Accepted: 23 May 2024 — Issue date: 01 Jul 2024
WEPR12
First comparison studies in dynamic aperture for nested magnets and baseline lattice in the FCC-ee
2485
A significant project such as the FCC-ee (with 91.17 km circumference) entails numerous challenges to ensure the stability and performance of the machine. In the pursuit of contributing to the improvement of energy consumption during its operation, the exploration of Nested Magnets (NMs) as a means to reduce synchrotron radiation has been undertaken. This paper presents first studies on the Dynamic Aperture (DA) and the Momentum Acceptance (MA) of this novel design to guide the next developments.
Paper: WEPR12
DOI: reference for this paper: 10.18429/JACoW-IPAC2024-WEPR12
About: Received: 15 May 2024 — Revised: 20 May 2024 — Accepted: 21 May 2024 — Issue date: 01 Jul 2024
WEPR13
Hybrid on-axis and off-axis top-up injection at the future circular lepton collider
2489
In order to maximize the integrated luminosity of the future circular lepton collider (FCC-ee), a top-up injection scheme is required. Amongst the four operation modes of FCC-ee, the Z operation mode has the highest stored beam energy in the collider ring with about 20 MJ per beam. Consequently, it is for this mode that the injection scheme is primarily optimized and is the focus of this contribution. Due to the synchrotron radiation cone of the injected beamlet at the interaction point (IP), the conventional off-axis injection scheme is not favored. As for the on-axis injection, it necessitates an energy offset for the injected beam and sufficient dynamic aperture in the collider ring. However, the energy acceptance of collider ring is only around ±1% for the latest baseline lattice of the Z mode, making this scheme challenging. Therefore, an hybrid on- and off-axis injection scheme is proposed to satisfy the requirements of dynamic aperture and energy acceptance. This contribution introduces the concept and discusses the optimization process used to balance energy and position offset of the injection scheme.
Paper: WEPR13
DOI: reference for this paper: 10.18429/JACoW-IPAC2024-WEPR13
About: Received: 15 May 2024 — Revised: 23 May 2024 — Accepted: 23 May 2024 — Issue date: 01 Jul 2024
WEPR21
Update in the optics design of monochromatization interaction region for direct Higgs s-channel production at FCC-ee
2520
The FCC-ee could allow the measurement of the electron Yukawa coupling via direct Higgs s-channel production at ~125 GeV centre-of-mass (CM) energy, provided that the CM energy spread of this channel, can be reduced to about 5–10 MeV to be comparable to the width of the standard model Higgs boson. The natural collision-energy spread at 125 GeV, due only to synchrotron radiation (SR), is about 50 MeV. Its reduction to the desired level can be accomplished by means of “monochromatization”, e.g., through introducing non-zero dispersion of opposite sign at the Interaction Point (IP), for the two colliding beams. This nonzero dispersion at the IP (horizontal or vertical) could be generated by different methods, requiring or not modifications of the Final Focus System (FFS) Local Chromaticity Correction (LCC) system. In this paper we report and compare the different recent Interaction Region (IR) optics design of this new possible collision mode.
Paper: WEPR21
DOI: reference for this paper: 10.18429/JACoW-IPAC2024-WEPR21
About: Received: 15 May 2024 — Revised: 22 May 2024 — Accepted: 22 May 2024 — Issue date: 01 Jul 2024
WEPR22
Review of MAD-X for FCC-ee studies
2524
The design of the electron-positron Future Circular Collider (FCC-ee) challenges the requirements on optics codes (like MAD-X) in terms of accuracy, consistency, and performance. Traditionally, MAD-X uses a transport formalism by expanding the transfer map about the origin up to second order to compute optics functions and synchrotron radiation integrals in the TWISS and EMIT modules. Conversely, particle tracking uses symplectic maps to propagate particles. These approaches solve the same problem using different approximations, resulting in a mismatch between the models used for tracking and for optics. While in a machine like LHC these differences are not relevant, for FCC-ee, given the size and the sensitivity to phase advance, the different approaches lead to important differences in the models. For instance, a tapering strategy that matches the tunes for optics needs to apply approximations that would mismatch the tune in tracking and vice versa. In this paper, we show the effectiveness of advanced methods that bring the maps used for optics and tracking closer and that will be used to reduce the gap between optics and tracking models to an acceptable level for FCC-ee studies.
Paper: WEPR22
DOI: reference for this paper: 10.18429/JACoW-IPAC2024-WEPR22
About: Received: 14 May 2024 — Revised: 18 May 2024 — Accepted: 18 May 2024 — Issue date: 01 Jul 2024
WEPR24
Initial design of a proton complex for the Muon Collider
2528
The proton complex is the first piece in the Muon Collider, it comprises a high power acceleration section, a compressor and a target delivery system. For the International Muon Collider Collaboration we are investigating the possibility of having a full energy 5-GeV linac followed by an accumulator and a compressor ring and finally a target delivery system. In this paper we present the initial studies for the complex and derived initial beam parameters at each interface.
Paper: WEPR24
DOI: reference for this paper: 10.18429/JACoW-IPAC2024-WEPR24
About: Received: 15 May 2024 — Revised: 19 May 2024 — Accepted: 19 May 2024 — Issue date: 01 Jul 2024
WEPR29
Update of the PLACET2 code for the low-energy acceleration stages of the muon collider
2548
This work describes improvements made to the tracking code PLACET2 to make it possible to simulate the acceleration from 250 MeV to 63 GeV in a future muon collider. This software was selected because of its unique ability to optimally simulate recirculating linacs, which are part of the proposed layout for this initial muon acceleration stage. PLACET2 has been updated to simulate non-relativistic particles and to consider particle beams of different species, charges and masses. The main changes were introduced in the longitudinal dynamics, synchrotron radiation and wakefield descriptions. In addition, the decay of particles has been added as a new feature. The changes were benchmarked in different tests against RF-Track, a code able to simulate low energy muon beams and their decay. Finally, the lattice of the 16.6 GeV arc in the initial acceleration stage of the muon collider was simulated with both PLACET2 and RF-Track, providing another test. All the results showed excellent agreement between both codes, verifying the implementation in PLACET2.
Paper: WEPR29
DOI: reference for this paper: 10.18429/JACoW-IPAC2024-WEPR29
About: Received: 07 May 2024 — Revised: 21 May 2024 — Accepted: 21 May 2024 — Issue date: 01 Jul 2024
WEPR37
The European Spallation Source neutrino super beam
2571
The discovery of neutrino Charge-Parity Violation (CPV) became an important candidate to explain the matter dominance in the Universe. The goal of the ESSnuSB project is to discover and measure neutrino CPV with unprecedented sensitivity*. The construction of the European Spallation Source, ESS, the world’s most intense proton source, represents an outstanding opportunity for such project to take place. ESSnuSB has been granted from EU in the framework of H2020 (2018-2022) and Horizon Europe (2023-2026) to make Design Studies. The aim of the first Design Study was to demonstrate that the ESS linac can be used to generate an intense neutrino beam by doubling its average beam power and that a megaton water Cherenkov detector can be constructed in a mine 360 km from ESS providing detection of neutrinos at the 2nd neutrino oscillation maximum. A CDR** has been published in which it is shown the high physics performance to discover CPV and precisely measure the violating parameter δCP. For this, the modification for neutrino generation to compress the proton pulse length from 2.86 ms, to 1.3 μs has been studied. The second, ongoing, Design Study, ESSnuSB+, is devoted to neutrino cross-section measurements relevant to the CPV discovery. Two facilities are proposed, a low energy nuSTORM (muons decaying to neutrinos in a race-track storage ring) and low energy ENUBET (pions decaying to a muon and a neutrino, allowing the neutrino beam to be monitored by detection of the decay muon).
Paper: WEPR37
DOI: reference for this paper: 10.18429/JACoW-IPAC2024-WEPR37
About: Received: 14 May 2024 — Revised: 23 May 2024 — Accepted: 23 May 2024 — Issue date: 01 Jul 2024
WEPR52
Bmad-Julia: a Julia environment for accelerator simulations including machine learning
2612
Bmad-Julia is a new, open-source software project for modern accelerator simulations with an emphasis on Machine Learning. As compared to existing accelerator codes, reverse differentiability, e.g. for the optimization of neural networks, will be embedded. Multiple standalone Julia packages are being developed that provide fundamental tools and methods commonly needed in accelerator simulations, it is envisaged that Bmad-Julia will be able to serve as the basis for developing new programs to meet the ever changing simulation requirements of high energy machines. By avoiding the necessity of "reinventing the wheel", programs that make use of Bmad-Julia packages can be developed in less time and with fewer bugs than programs developed from scratch. Included will be a package for accelerator lattice instantiation and bookkeeping, a package for handling physical and atomic constants, and a package for truncated Power Series Algebra (TPSA) with routines for manipulations and analysis including map inversion, partial map inversion, normal form decomposition, Poisson bracket, etc. Ultimately, all features of today’s versatile Bmad toolkit will be transferred, including polarized beams, radiation effects, beam scattering, symplectic tracking, and long-term dynamics. Discussed is the present state of the project as well as plans for the future.
Paper: WEPR52
DOI: reference for this paper: 10.18429/JACoW-IPAC2024-WEPR52
About: Received: 15 May 2024 — Revised: 16 May 2024 — Accepted: 17 May 2024 — Issue date: 01 Jul 2024
WEPR56
Xsuite: an integrated beam physics simulation framework
2623
Xsuite is a modular simulation package bringing to a single flexible and modern framework capabilities of different tools developed at CERN in the past decades notably MAD-X Sixtrack Sixtracklib COMBI and PyHEADTAIL. The suite consists of a set of Python modules (Xobjects, Xpart, Xtrack, Xcoll, Xfields, Xdeps) that can be flexibly combined together and with other accelerator-specific and general-purpose python tools to study complex simulation scenarios. Different computing platforms are supported including conventional CPUs as well as GPUs from different vendors. The code allows for symplectic modeling of the particle dynamics combined with the effect of synchrotron radiation impedances feedbacks space charge electron cloud beam-beam beamstrahlung and electron lenses. For collimation studies beam-matter interaction is simulated using the K2 scattering model or interfacing Xsuite with the BDSIM/Geant4 library and with the FLUKA code. Methods are made available to compute and optimize the accelerator lattice functions, chromatic properties and equilibrium beam sizes. By now the tool has reached a mature stage of development and is used for simulations studies by a large and diverse user community.
Paper: WEPR56
DOI: reference for this paper: 10.18429/JACoW-IPAC2024-WEPR56
About: Received: 15 May 2024 — Revised: 23 May 2024 — Accepted: 23 May 2024 — Issue date: 01 Jul 2024
WEPR59
Developing nested auto-differentiation tracking code for beam dynamics optimization
2635
An innovative particle tracking code is in development using the Julia programming language, utilizing the power of auto-differentiation (AD). With the aid of specifically designed truncated power series algebra (TPSA) methods and built-in Julia AD packages, this code enables automatic calculation of derivatives with respect to selected parameters of interest. This tracking code provides a flexible and powerful solution for accelerator physicists applicable across various research topics, especially for beam dynamics optimization works.
Paper: WEPR59
DOI: reference for this paper: 10.18429/JACoW-IPAC2024-WEPR59
About: Received: 13 May 2024 — Revised: 17 May 2024 — Accepted: 17 May 2024 — Issue date: 01 Jul 2024
THBD1
Commissioning optics: larger dynamic aperture and Touschek lifetime for the (temporary) cost of larger horizontal emittance in 4th generation light sources
2948
Reduction of dynamic aperture encountered in 4th generation light sources presents a challenge for injection efficiency and commissioning. It’s possible that only after BBA and optics corrections are applied, will the dynamic aperture be sufficient for reasonable injection efficiency. Furthermore, it’s only after a circulating beam is established that BBA, BPM calibration, and other optics corrections can be applied. Limited dynamic aperture not only makes standard top-up operation more challenging; during commissioning this challenge is even greater. To address this problem, we have developed a lattice design that allows for both low emittance optics (for standard user beam operation) and what we have called “commissioning optics” which is a set of lattice parameters that allows for larger dynamic aperture and Touschek Lifetime at the (temporary) cost of larger horizontal emittance.
Paper: THBD1
DOI: reference for this paper: 10.18429/JACoW-IPAC2024-THBD1
About: Received: 15 May 2024 — Revised: 19 May 2024 — Accepted: 19 May 2024 — Issue date: 01 Jul 2024
THPC01
Status of the ALBA-II lattice studies
2964
Due to the constrains imposed by the tight geometry of the ALBA storage ring, the initial 6BA lattice envisioned for the ALBA-II upgrade was reconsidered in favor of a more relaxed 5BA configuration. The first engineering studies of magnets and vacuum chambers made evident many short comings of the 6BA optics. The here proposed 5BA optics allows for an easier integration at cost of a small increase of the natural emittance. The employed linear and non-linear optics optimization process is here described along with the first studies about dynamic aperture and lifetime.
Paper: THPC01
DOI: reference for this paper: 10.18429/JACoW-IPAC2024-THPC01
About: Received: 14 May 2024 — Revised: 21 May 2024 — Accepted: 23 May 2024 — Issue date: 01 Jul 2024
THPC04
Sextupole offset effects on the storage ring linear optics
2968
Even though the strengths are weaker, different from quadrupole offsets, sextupole offsets are causing more complicated disturbances on the storage ring optics. They are making orbit distortion and quadrupole kicks as well as couplings. The offsets in chromatic sextupoles can affect the correction of chromaticity too. The closed orbit corrections in modern storage rings are fast and reliable, but their main focus is correcting the orbit to the quadrupole centers and the orbit distortion from a sextupole offset can make orbit offsets at other sextupoles which can be iterated. In this paper, we study the impact of the sextupole offsets on the linear optics in NSLS-II storage ring.
Paper: THPC04
DOI: reference for this paper: 10.18429/JACoW-IPAC2024-THPC04
About: Received: 15 May 2024 — Revised: 19 May 2024 — Accepted: 19 May 2024 — Issue date: 01 Jul 2024
THPC13
Optics design of a compact helium synchrotron for advanced cancer therapy
2991
The design of a helium synchrotron for cancer therapy is being studied and optimized in the context of the Next Ion Medical Machine Study (NIMMS) at CERN. In particular, the effects of combined-function magnets and their geometry on the optics functions and hence on the beam size are evaluated. Moreover, the introduction of defocusing quadrupoles in the lattice is investigated as a means of better controlling the optics in both planes, while sextupoles for chromaticity control and resonant extraction are introduced. The updated lattice design is simulated to identify potential limitations in terms of nonlinear dynamics due to the low periodicity of the lattice and propose a regime for operations from the transverse beam dynamics’ perspective.
Paper: THPC13
DOI: reference for this paper: 10.18429/JACoW-IPAC2024-THPC13
About: Received: 13 May 2024 — Revised: 21 May 2024 — Accepted: 21 May 2024 — Issue date: 01 Jul 2024
THPC17
Mini-beta optics commissioning at the European Synchrotron Radiation Facility Extremely Brilliant Source
3007
The European Synchrotron Radiation Facility (ESRF) presently operates with the Hybrid Multi-Bend Achromat (HMBA) lattice that features 𝛽-functions of 6.9 m and 2.7 m in the horizontal and vertical planes at the center of the straight sections. New optics were designed to increase the brilliance of beam lines with a single undulator placed at the center of the straight section. The reduction of the in-vacuum undulator gap and of the beta-functions both contribute to this increase. This paper reports on the optics beam commissioning results and experimental observation with the reduced in-vacuum undulator gap.
Paper: THPC17
DOI: reference for this paper: 10.18429/JACoW-IPAC2024-THPC17
About: Received: 14 May 2024 — Revised: 21 May 2024 — Accepted: 23 May 2024 — Issue date: 01 Jul 2024
THPC20
Experimental measurements for extracting nonlinear invariants
3015
Nonlinear integrable optics are a promising alternative approach to lattice design. The integrable optics test accelerator (IOTA) at Fermilab has been constructed for dedicated studies of magnetostatic elliptical elements as described by Danilov and Nagaitsev. The most compelling verification of correct implementation of the NIO lattice is direct observation of the analytically expected invariants. This report outlines the experimental and analytical methods for extracting the nonlinear invariants of motion from data gathered in the last IOTA run.
Paper: THPC20
DOI: reference for this paper: 10.18429/JACoW-IPAC2024-THPC20
About: Received: 15 May 2024 — Revised: 21 May 2024 — Accepted: 21 May 2024 — Issue date: 01 Jul 2024
THPC21
Measured dynamic aperture and detuning of nonlinear integrable optics
3019
One of the most promising advantages of nonlinear integrable optics is strong amplitude dependent tune shift without degrading the dynamic aperture. The integrable optics test accelerator (IOTA) at Fermilab is constructed around nonlinear lattice elements of the elliptical type as described by Danilov and Nagaitsev. Detuning and dynamic aperture scans in IOTA were performed using a fast dipole kicker and a low emittance electron beam. The evolution of the dynamic aperture and detuning for different configurations of the integrable optics lattice are presented.
Paper: THPC21
DOI: reference for this paper: 10.18429/JACoW-IPAC2024-THPC21
About: Received: 15 May 2024 — Revised: 21 May 2024 — Accepted: 21 May 2024 — Issue date: 01 Jul 2024
THPC23
Machine-assisted discovery of integrable symplectic mappings
3027
Integrable systems possess a hidden symmetry associated with the existence of conserved quantities known as integrals of motion. These systems play an important role in understanding general dynamics in accelerators and have potential for future designs. This work will cover two automated methods for finding integrable symplectic maps of the plane. The first algorithm is based on the observation that the evolution of an integrable system in phase space is confined to a lower-dimensional submanifold of a specific type. The second algorithm relies on an analysis of dynamical variables. Both methods rediscover some of the famous McMillan-Suris integrable mappings and ultra-discrete Painlev\'e equations. Over 100 new integrable families are presented and analyzed, some of which are isolated in the space of parameters, while others are families with one parameter (or the ratio of parameters) being either continuous or discrete. In addition, the newly discovered maps are related to a general 2D symplectic map through the use of discrete perturbation theory. A method is proposed for constructing smooth near-integrable dynamical systems based on mappings with polygon invariants.
Paper: THPC23
DOI: reference for this paper: 10.18429/JACoW-IPAC2024-THPC23
About: Received: 15 May 2024 — Revised: 19 May 2024 — Accepted: 22 May 2024 — Issue date: 01 Jul 2024
THPC32
Correction of nonlinear lattice with closed orbit modulation
3056
We propose to correct nonlinear lattice optics with the closed-orbit modulation technique. Closed orbit modulation with large amplitude samples the nonlinear optics. Fitting such data measured on the machine to the lattice model with appropriate lattice parameters would reveal the nonlinear errors and provide a means for correction. The method is tested in simulation and is shown to work in principle. Experimental data were also taken. However, more work is needed to understand the other effects on the mode amplitude dependence on modulation amplitude on a real machine.
Paper: THPC32
DOI: reference for this paper: 10.18429/JACoW-IPAC2024-THPC32
About: Received: 15 May 2024 — Revised: 19 May 2024 — Accepted: 19 May 2024 — Issue date: 01 Jul 2024
THPC34
Linear optics correction of an asymmetric storage ring lattice
3064
The SSRF storage ring has been upgraded to an asymmetric lattice containing two super-bend cells, two double-mini-βy optics (DMB) cells and a superconducting wiggler (SCW) in 2019. Due to the destruction in structural symmetry, the restoration of linear optics becomes an essential issue in commissioning and routine beam dynamics maintenance. During the initial commissioning, the linear optics were well corrected with the LOCO method even though the SCW had not yet been installed. Recently, it has been found that the setups of some quadrupole power supplies tend to exceed the limits and deviate significantly from the intrinsic theoretical values, and the beta-functions and the tunes cannot be commendably recovered, leading to degradation of the storage ring performance. In this paper, the linear optics correction of the SSRF storage ring is introduced, the difficulties of the linear optics correction in asymmetric lattice are investigated, and the improved correction method and related application results are introduced.
Paper: THPC34
DOI: reference for this paper: 10.18429/JACoW-IPAC2024-THPC34
About: Received: 14 May 2024 — Revised: 19 May 2024 — Accepted: 21 May 2024 — Issue date: 01 Jul 2024
THPC35
Impact of insertion devices on SSRF‑U lattice
3068
The Shanghai Synchrotron Radiation Facility upgrade (SSRF-U) lattice is a 4th generation, 3 GeV, upgrade plan for SSRF. It aims to reach the diffraction limit while keeping the existing beam lines and spaces. The majority of insertion devices (IDs) in operation of current SSRF will be considered as the ID scheme in SSRF-U. The kick-map method has been used to build ID models, including the EPUs and SCW. Optical distortion caused by IDs was compensated using both local and global corrections. Then, frequency map analysis (FMA) method was used to identify potentially dangerous resonance lines. After considering high-order magnetic field errors, the dynamic aperture, energy acceptance, and Touschek lifetime were examined.
Paper: THPC35
DOI: reference for this paper: 10.18429/JACoW-IPAC2024-THPC35
About: Received: 13 May 2024 — Revised: 19 May 2024 — Accepted: 21 May 2024 — Issue date: 01 Jul 2024
THPC71
Minimizing space charge tune spread and increasing beam quality parameters with circular modes
3190
Space charge has been a limiting effect for low energy accelerators inducing emittance growth and tune spread. Tune shift and tune spread parameters are important for avoiding resonances, which limits intensity of the beam. Circular modes are round beams with intrinsic flatness that are generated through strong coupling, where intrinsic flatness can be transformed to real plane flatness through decoupling. It is understood that flat beams increase the quality parameters of a beam due to one of the plane emittances being smaller than the other plane since luminosity and beam brightness depend inversely on the beam emittances. We show that circular mode beams manifest smaller space charge tune spread compared to uncorrelated round beams, which allows better systematic control of operating point of the beam. Minimized tune spread allows flexible operating points on the tune map. We also dedicate current and intrinsic flatness ratio limits on circular modes, which increase quality parameters without detrimental effects on the emittance increase.
Paper: THPC71
DOI: reference for this paper: 10.18429/JACoW-IPAC2024-THPC71
About: Received: 15 May 2024 — Revised: 21 May 2024 — Accepted: 21 May 2024 — Issue date: 01 Jul 2024
THPC81
Study of the beam-beam interaction in an electron-positron collider with large Piwinski angle and crabbed waist
3229
To achieve very high luminosity, the next generation circular colliders adopt the crab waist collision scheme with a large Piwinski angle. In this scheme, beams collide with high current, low emittances, and small beta functions at the interaction point (IP). However, several effects arising from these extreme parameters, especially the coherent X-Z instability, will significantly impact the collider's performance, necessitating dynamic processing of longitudinal motion in a three-dimensional self-consistent treatment. The transverse vibration becomes coupled with the longitudinal motion, as well as the increase in horizontal beam size alters the interaction between beams and corresponding beam-induced effects. These instabilities limit the stable high luminosity area for the selected working point of the original design. Therefore, it is necessary to optimize the safe area of the working point by readjusting the parameters of the IP.In this paper, based on the Super Tau-Charm Facility (STCF) project in China, the instability caused by beam interactions is studied through numerical simulation. The relationship between the parameters at the IP and the stable selection area of the working point is systematically explored. The regularities found from simulations can assist future high luminosity electron-positron colliders in selecting the corresponding parameters. Additionally, some methods, such as adding adjustable devices to achieve stable high luminosity, are also proposed.
Paper: THPC81
DOI: reference for this paper: 10.18429/JACoW-IPAC2024-THPC81
About: Received: 12 May 2024 — Revised: 17 May 2024 — Accepted: 17 May 2024 — Issue date: 01 Jul 2024
THPC82
Design of the low-emittance complex bend lattice
3233
The demands of a higher brightness photon beam push the electron beam emittance of storage rings towards a diffraction-limited level. The concept of multi-bend achromat (MBA) structure and its variations, containing multiple dipoles in a cell, has been widely employed in the fourth-generation storage ring light sources. Recently, a novel concept of lattice structure, called complex bend lattice, extends the option for low emittance ring lattice design. This paper presents the developed low-emittance complex bend lattices. The benefits of using complex bends include low natural emittance, long straights for IDs, more free space for accelerator equipment, and reduced power consumption for magnets.
Paper: THPC82
DOI: reference for this paper: 10.18429/JACoW-IPAC2024-THPC82
About: Received: 15 May 2024 — Revised: 19 May 2024 — Accepted: 24 May 2024 — Issue date: 01 Jul 2024
THPC83
Test of parallel beam-based alignment at NSLS-II
3237
Misalignment of magnets in the storage rings causes trajectory deviation when the beam traverses through magnets, resulting in the degraded performance of linear optics and nonlinear dynamics. The beam-based alignment (BBA) technique is commonly used to steer the beam passing through the centers of magnets. Recently, a new method has been developed to determine the centers of multiple magnets simultaneously [1]. In this paper, the test of this fast BBA method at NSLS-II is presented.
Paper: THPC83
DOI: reference for this paper: 10.18429/JACoW-IPAC2024-THPC83
About: Received: 15 May 2024 — Revised: 19 May 2024 — Accepted: 22 May 2024 — Issue date: 01 Jul 2024
THPG06
Tune feedback system in the Taiwan photon source
3258
The paper outlines the successful implementation of a global tune feedback system at the Taiwan Photon Source (TPS) to compensate the tune variation resulting from adjustments in the gap and phase of the insertion devices. The global tune feedback system deployed in the TPS employs two families of quadrupole magnets to sustain betatron tunes at the desired working point. The adjustment currents (feedback quantities) are crucial for this process, which are calculated from a tune response matrix derived from the lattice model, with tune shift quantities provided by the bunch-by-bunch feedback system, and the algorithm of singular value decomposition (SVD).
Paper: THPG06
DOI: reference for this paper: 10.18429/JACoW-IPAC2024-THPG06
About: Received: 15 May 2024 — Revised: 20 May 2024 — Accepted: 20 May 2024 — Issue date: 01 Jul 2024
THPR51
A large momentum acceptance gantry for light-weight proton therapy facility: its beam lattice, magnets design and clinical advantages
3632
As one of the state-of-the-art radiotherapy approaches, proton therapy possesses conformal dose profiles yet expensive cost. Designing a facility with a small footprint and a high treatment efficiency is the main goal for researchers to fulfill the potential of proton therapy and make it more affordable both for vendors and patients. In this contribution, the design of a light-weight proton therapy gantry based on the alternating-gradient canted-cosine-theta (AG-CCT) super-conducting (SC) magnet is presented. The AG-CCT magnets adopt large bores and combined function design. With fine field harmonic control and fringe field shape optimization of the magnets, the multi-particle tracking results prove that the gantry achieves a momentum acceptance of ±8%. So that the full energy range from 70 to 230 MeV can be covered with merely 3 field switch points. Combined with a fast degrader component, whose switch time is below 50 ms, the energy modulation speed can be greatly fastened. To fully utilize the advantages of the large momentum acceptance gantry, the energy spread of the proton beam is expanded and a reduced treatment plan is proposed. Compared with the standard treatment plan, the energy layers number of a prostate case is reduced by 61.3% with comparable plan quality. In summary, the proposed gantry has significant superiority both in manufacture and clinical aspects.
Paper: THPR51
DOI: reference for this paper: 10.18429/JACoW-IPAC2024-THPR51
About: Received: 14 May 2024 — Revised: 17 May 2024 — Accepted: 17 May 2024 — Issue date: 01 Jul 2024
THPS69
Mechanical design, structural requirements and optimization of the FCC e+e- interaction region components
3904
This paper describes the mechanical design of the Future Circular Collider e+e- interaction region. The Future Circular Collider, as a forefront particle accelerator project, demands meticulous attention to the mechanical integrity and performance of its components, to the integration of the different systems and to the respect of the spatial constraint. The vacuum chamber design, the support tube and the bellows design are reported, highlighting the solutions adopted. The structural optimization method of the support structure is also presented, as well as the results obtained.
Paper: THPS69
DOI: reference for this paper: 10.18429/JACoW-IPAC2024-THPS69
About: Received: 14 May 2024 — Revised: 19 May 2024 — Accepted: 20 May 2024 — Issue date: 01 Jul 2024