NAPAC2016 - List of Keywords (quadrupole)

Paper	Title	Other Keywords	Page
MOB3CO04	High Luminosity 100 TeV Proton-Antiproton Collider	ion, proton, collider, antiproton	45
	S.J. Oliveros, J.G. Acosta, L.M. Cremaldi, T.L. Hart, D.J. Summers UMiss, University, Mississippi, USA
	The energy scale for new physics is known to be in the multi-TeV range, signaling the potential need for a collider beyond the LHC. A 10³⁴ cm−2 s−1 luminosity 100 TeV proton-antiproton collider is explored. Prior engineering studies for 233 and 270 km circumference tunnels were done for Illinois dolomite and Texas chalk signaling manageable tunneling costs. At a ppbar the cross section for high mass states is of order 10x higher with antiproton collisions, where antiquarks are directly present rather than relying on gluon splitting. The higher cross sections reduce the synchrotron radiation in superconducting magnets, because lower beam currents can produce the same rare event rates. In our design the increased momentum acceptance (11 ± 2.6 GeV/c) in a Fermilab-like antiproton source is used with septa to collect 12x more antiprotons in 12 channels. For stochastic cooling, 12 cooling systems would be used, each with one debuncher/momentum equalizer ring and two accumulator rings. One electron cooling ring would follow. Finally antiprotons would be recycled during runs without leaving the collider ring, by joining them to new bunches with synchrotron damping.
	Slides MOB3CO04 [1.304 MB]
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-NAPAC2016-MOB3CO04
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MOB4CO03	Design of Muon Collider Lattices	ion, collider, sextupole, factory	69
	Y.I. Alexahin Fermilab, Batavia, Illinois, USA
	Funding: Work supported by Fermi Research Alliance, LLC under Contract DE-AC02-07CH11359 with the U.S. DOE A Muon Collider promises unique opportunities both as an energy frontier machine and as a factory for detailed study of the Higgs boson and other particles. However, in order to achieve a competitive level of luminosity a number of demanding requirements to the collider optics should be satisfied arising from short muon lifetime and relatively large values of the transverse emittance and momentum spread in muon beams that can realistically be obtained with ionization cooling. Basic solutions which make possible to achieve these goals with Nb3Sn magnet parameters are presented.
	Slides MOB4CO03 [0.794 MB]
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-NAPAC2016-MOB4CO03
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MOPOB40	Quench Training Analysis of Nb3Sn Accelerator Magnets	ion, dipole, operation, magnet-design	155
	S. Stoynev, K.H. Riemer, A.V. Zlobin Fermilab, Batavia, Illinois, USA
	Funding: This work is supported by Fermi Research Alliance, LLC, under contract No. DE-AC02-07CH11359 with the U.S. Department of Energy. Nb3Sn accelerator magnet technology has made significant progress during the past decades. Thanks to that 11-12 T Nb3Sn dipoles and quadrupoles are planned to be used in accelerators such as LHC in near future for the luminosity upgrade and in longer term for the LHC energy upgrade or a future Very High Energy pp Collider. However, all the state of the art Nb3Sn accelerator magnets show quite long training. This specific feature significantly raises the required design margin or limit the nominal operation field of Nb3Sn accelerator magnets and, thus, increases their cost. To resolve this problem Fermilab has launched a study aiming to analyze the relatively large amount of Nb3Sn magnet training data accumulated at Fermilab magnet test facility. The ultimate goal is to correlate magnet design and manufacturing features and magnet material properties with training performance parameters which will eventually allow us to optimize both the magnet design, fabrication and the training processes. This paper describes the general strategy of the analysis and presents the first results based on partial data processing. Conclusions and further steps are also outlined and discussed.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-NAPAC2016-MOPOB40
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MOPOB41	Field Quality Measurements in the FNAL Twin-Aperture 11 T Dipole for LHC Upgrades	ion, dipole, magnet-design, ion-effects	158
	T. Strauss, G. Apollinari, E.Z. Barzi, G. Chlachidze, J. DiMarco, A. Nobrega, I. Novitski, S. Stoynev, D. Turrioni, G. Velev, A.V. Zlobin Fermilab, Batavia, Illinois, USA B. Auchmann, S. Izquierdo Bermudez, M. Karppinen, L. Rossi, F. Savary, D. Smekens CERN, Geneva, Switzerland
	Funding: *Work is supported by Fermi Research Alliance, LLC, under contract No. DE-AC02-07CH11359 with the U.S. Department of Energy and European Commission under FP7 project HiLumi LHC, GA no.284404 FNAL and CERN magnet groups are developing a twin-aperture Nb3Sn 11 T dipole suitable for installation in the LHC to provide room for additional collimators in the dispersion suppressor (DS) areas. Two of these magnets with a collimator in between will replace one regular MB dipole. A single-aperture 2-m long dipole demonstrator and two 1-m long dipole models have been assembled and tested at FNAL in 2012-2014. The 1 m long collared coils were then assembled into the twin-aperture configuration and tested in 2015. The first magnet test was focused on the quench performance of twin-aperture magnet configuration including magnet training, ramp rate sensitivity and temperature dependence of magnet quench current. In the second test performed in July 2016 field quality in one of the two magnet apertures has been measured and compared with the data for the single-aperture models. These results are reported and discussed in this paper.
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MOPOB54	Superferric Arc Dipoles for the Ion Ring and Booster of JLEIC	ion, dipole, multipole, collider	184
	P.M. McIntyre, J. Breitschopf, T. Elliott, R. Garrison, J. Gerity, J.N. Kellams, A. Sattarov Texas A&M University, College Station, USA D. Chavez DCI-UG, León, Mexico
	Funding: This work was supported by a grant from the NP Division of the US Dept. of Energy. The JLEIC project requires 3 T superferric dipoles and quadrupoles for the half-cell arcs of its Ion Ring and Booster. A superferric design using NbTi cable-in-conduit conductor is being developed. A mockup winding has been completed, with the objectives to develop and evaluate the coil structure and the winding tooling and methods, and to measure errors in the position of each cable turn in the dipole body. The results of the mockup winding study are presented. The CIC design is now ready for construction and testing of a first model dipole.
	Poster MOPOB54 [1.147 MB]
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MOPOB55	Room Temperature Magnets in FRIB Driver Linac	ion, linac, alignment, dipole	188
	Y. Yamazaki, N.K. Bultman, E.E. Burkhardt, F. Feyzi, K. Holland, A. Hussain, M. Ikegami, F. Marti, S.J. Miller, T. Russo, J. Wei, Q. Zhao FRIB, East Lansing, USA W.J. Yang, Q.G. Yao IMP/CAS, Lanzhou, People's Republic of China
	Funding: Work supported by the U.S. Department of Energy Office of Science under Cooperative Agreement DE-SC0000661 and the National Science Foundation under Cooperative Agreement PHY-1102511. The FRIB Driver Linac* is to accelerate all the stable ions beyond 200 MeV/nucleon with a beam power of 400 kW. The linac is unique, being compactly folded twice. In this report, the room temperature magnets, amounting 147 in total, after Front End with a 0.5-MeV RFQ, are detailed, emphasizing the rotating coil field measurements and fiducialization. *E. Pozdeyev et al., "Status of FRIB" in this conference. T. Xu, "Superconducting Cryomodule Development and Production for the FRIB Linac" in this conference.
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MOPOB59	Magnet Design for the Splitter/Combiner Regions of CBETA, the Cornell-Brookhaven Energy-Recovery-Linac Test Accelerator	ion, dipole, linac, magnet-design	201
	J.A. Crittenden, D.C. Burke, Y.L.P. Fuentes, C.E. Mayes, K.W. Smolenski Cornell University (CLASSE), Cornell Laboratory for Accelerator-Based Sciences and Education, Ithaca, New York, USA
	Funding: Supported by NSF award DMR-0807731, DOE grant DE-AC02-76SF00515, and New York State. The Cornell-Brookhaven Energy-Recovery-Linac Test Accelerator (CBETA) will provide a 150-MeV electron beam using four acceleration and four deceleration passes through the Cornell Main Linac Cryomodule housing six 1.3-GHz superconducting RF cavities. The return path of this 76-m-circumference accelerator will be provided by 10⁶ fixed-field alternating-gradient (FFAG) cells which carry the four beams of 42, 78, 114 and 150-MeV. Here we describe magnet designs for the splitter and combiner regions which serve to match the on-axis linac beam to the off-axis beams in the FFAG cells, providing the path-length adjustment necessary to energy recovery for each of the four beams. The path lengths of the four beamlines in each of the splitter and combiner regions are designed to be adapted to 1-, 2-, 3-, and 4-pass staged operations. Design specifications and modeling for the 24 dipole and 32 quadrupole electromagnets in each region are presented. The CBETA project will serve as the first demonstration of multi-pass energy recovery using superconducting RF cavities with FFAG cell optics for the return loop.
	Poster MOPOB59 [8.982 MB]
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-NAPAC2016-MOPOB59
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TUPOA36	Computed Tomography of Transverse Phase Space	ion, simulation, instrumentation, optics	358
	A.C. Watts, C. Johnstone, J.A. Johnstone Fermilab, Batavia, Illinois, USA
	Funding: Work supported by Fermi Reserach Alliance, LLC under Contract no. DE-AC02-07CH11359 with the United States Department of Energy. Two computed tomography techniques are explored to reconstruct beam transverse phase space using both simulated beam and multi-wire profile data in the Fermilab Muon Test Area ("MTA") beamline. Both Filtered Back-Projection ("FBP") and Simultaneous Algebraic Reconstruction Technique ("SART") algorithms are considered and compared. Errors and artifacts are compared as a function of each algorithm's free parameters, and it is shown through simulation and MTA beamline profiles that SART is advantageous for reconstructions with limited profile data. awatts@fnal.gov, cjj@fnal.gov, jjohnstone@fnal.gov
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-NAPAC2016-TUPOA36
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TUPOA46	Development of a Python-Based Emittance Calculator at Fermilab Science & Technology (FAST) Facility	emittance, ion, experiment, solenoid	376
	A.T. Green Northern Illinois Univerity, DeKalb, Illinois, USA Y.-M. Shin Fermilab, Batavia, Illinois, USA Y.-M. Shin Northern Illinois University, DeKalb, Illinois, USA
	Beam emittance is an important characteristic which helps to describe a charged particle beam. In linear accelerators (linac), it is critical to characterize the beam phase space parameters and, in particular, to precisely measure transverse beam emittance. The quadrupole scan (quad-scan) is a well established technique used to characterize transverse beam parameters in four-dimensional phase space. Quad-scans are very time consuming and off-line analysis is needed to extrapolate the beam phase space parameters. We have developed a computational algorithm with Python scripts to automatically estimate beam parameters, in particular beam emittance, using the quadrupole scan technique in the electron linac of Fermilab Accelerator Science and Technology (FAST) facility. These Python scripts have decreased the time it takes to perform a single quad scan from a few hours to a few minutes. From the experimental data, the emittance calculator quickly delivers various results including: transverse emittance, Courant-Snyder parameters, and Beam Size (squared) vs Quadrupole field strength plots, among others.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-NAPAC2016-TUPOA46
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TUPOA48	A High-Level Python Interface to the Fermilab ACNET Control System	ion, controls, emittance, interface	383
	P. Piot Fermilab, Batavia, Illinois, USA A. Halavanau Northern Illinois University, DeKalb, Illinois, USA
	This paper discusses the implementation of a PYTHON-based high-level interface to the Fermilab ACNET control system. We will especially present examples of applications which include the interfacing of an ELEGANT beam-dynamics model to assist lattice matching and an automated emittance measurement via the quadrupole-scan method.
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TUB4CO04	Progress on the Magnetic Performance of Planar Superconducting Undulators	ion, undulator, photon, octupole	477
	M. Kasa, C.L. Doose, J.D. Fuerst, E. Gluskin, Y. Ivanyushenkov ANL, Argonne, Illinois, USA
	Funding: Work supported by the U.S. Department of Energy, Office of Science, under Contract No. DE-AC02-06CH11357. One of the primary goals of the superconducting undulator (SCU) program at the Advanced Photon Source (APS) is to achieve a high quality undulator magnetic field without the need for magnetic shimming to tune the device. Over the course of two years, two SCUs were designed, manufactured, assembled, and tested at the APS. Both SCUs were one meter in length with a period of 1.8 cm. After magnetic measurements of the first undulator were completed, several design changes were made in order to improve the quality of the undulator magnetic field. The design modifications were implemented during construction and assembly of the second SCU. The details of the design modifications along with a comparison of the magnetic measurement results will be described.
	Slides TUB4CO04 [6.426 MB]
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-NAPAC2016-TUB4CO04
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TUPOB11	Quantification of Octupole Magnets at the University of Maryland Electron Ring	ion, octupole, multipole, lattice	503
	H. Baumgartner, B. Beaudoin, S. Bernal, I. Haber, T.W. Koeth, D.B. Matthew, K.J. Ruisard, M.R. Teperman UMD, College Park, Maryland, USA
	Funding: Funding for this project is provided by DOE-HEP and the NSF Accelerator Science Program The intensity frontier is limited by the ability to propagate substantial amounts of beam current without resulting in particle scrapping and/or losses from resonant growth and halo formation. Modern accelerators are based on the theories developed in the 1950's that assume particle motion is bounded and subject to linear forces. Recent theoretical developments have demonstrated that a strongly nonlinear lattice can be used to stably transport an intense beam has resulted in a fundamental rethinking of the conventional wisdom. A lattice composed of strong nonlinear magnets is predicted by theory to damp resonances while maintaining dynamic aperture. Results of rotating coil measurements, magnetic field scans and simulations will be presented, quantifying the multi-pole moments and fringe fields in the 1st generation Printed Circuit Board (PCB) octupoles for UMER's nonlinear lattice experiments.
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TUPOB12	Experimental Plans for Single-Channel Strong Octupole Fields at the University of Maryland Electron Ring	ion, lattice, octupole, focusing	507
	K.J. Ruisard, H. Baumgartner, B. Beaudoin, I. Haber, T.W. Koeth, M.R. Teperman UMD, College Park, Maryland, USA
	Funding: Funding for this project and travel is provided by DOE-HEP, NSF GRFP and NSF Accelerator Science Program Nonlinear quasi-integrable optics is a promising development on the horizon of high-intensity ring design. Large amplitude-dependent tune spreads, driven by strong nonlinear magnet inserts, lead to decoupling from incoherent tune resonances. This reduces intensity-driven beam loss while quasi-integrability ensures a well-contained beam. In this paper we discuss on-going work to install and interrogate a long-octupole channel at the University of Maryland Electron Ring (UMER). This is a discrete insert that occupies 20 degrees of the ring, consisting of independently powered printed circuit octupole magnets. Transverse confinement is obtained with quadrupoles external to this insert. Operating UMER as a non-FODO lattice, in order to meet the beam-envelope requirements of the quasi-integrable lattice, is a challenge. We discuss efforts to match the beam and optimize steering solutions. We also discuss our experiences operating a distributed strong octupole lattice.
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TUPOB26	Dynamics of Intense Beam in Quadrupole-Duodecapole Lattice Near Sixth Order Resonance	ion, resonance, focusing, lattice	552
	Y.K. Batygin, T.T. Fronk LANL, Los Alamos, New Mexico, USA
	Funding: Work supported by US DOE under contract DE-AC52-06NA25396 The presence of duodecapole components in quadrupole focusing field results in excitation of sixth-order single-particle resonance if the phase advance of the particles transverse oscillation is close to 60 deg. This phenomenon results in intensification of beam losses. We present analytical and numerical treatment of particle dynamics in the vicinity of sixth-order resonance. The topology of resonance in phase space is analyzed. Beam emittance growth due to crossing of resonance islands is determined. Halo formation of intense beams in presence of resonance conditions is examined.
	Poster TUPOB26 [3.523 MB]
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TUPOB37	Diffusion Measurement From Transverse Echoes	ion, dipole, simulation, octupole	572
	Y.S. Li Carleton College, Northfield, Minnesota, USA
	Beam diffusion is an important measure of stability in high intensity beams. Traditional methods of diffusion characterization (e.g. beam scraping) can be very time-consuming. In this study, we investigate the transverse beam echo as a novel technique for measuring beam diffusion. Numerical analysis of maximum echo amplitude was compared with theoretical predictions with and without diffusion. We succeeded in performing a self-consistent measurement of the linear diffusion coefficient via a parameter scan over delay time. We also demonstrated the effectiveness of pulsed quadrupoles as a means to boost echo amplitude. Finally, multi-echo sequences were also briefly investigated. Results from this study will support planned experiments at the IOTA proton ring under construction at Fermilab.
	Poster TUPOB37 [2.109 MB]
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-NAPAC2016-TUPOB37
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TUPOB44	Final 6d Muon Ionization Cooling Using Strong Focusing Quadrupoles	ion, emittance, betatron, collider	592
	T.L. Hart, J.G. Acosta, L.M. Cremaldi, S.J. Oliveros, D.J. Summers UMiss, University, Mississippi, USA D.V. Neuffer Fermilab, Batavia, Illinois, USA
	Low emittance muon beam lines and muon colliders are potentially a rich source of BSM physics for future experimenters. A normalized transverse muon emittance of 280 microns has been achieved in simulation with short solenoids and a betatron function of 3 cm. Here we use ICOOL, G4Beamline, and MAD-X to explore using a flat 400 MeV/c muon beam and strong focusing quadrupoles to achieve a normalized transverse emittance of 100 microns and finish 6D cooling. The low beta regions, as low as 5 mm, produced by the quadrupoles are occupied by dense, low Z absorbers, such as lithium hydride or beryllium, that cool the beam. Equilibrium transverse emittance is linearly proportional to the beta function. Reverse emittance exchange with septa and/or wedges is then used to decrease transverse emittance from 100 to 25 microns at the expense of longitudinal emittance for a high energy lepton collider. Cooling challenges include chromaticity correction, momentum passband overlap, quadrupole acceptance, and staying in phase with RF.
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TUPOB52	Linear Optics Characterization and Correction Method Using Turn-By-Turn BPM Data Based on Resonance Driving Terms with Simultaneous BPM Calibration Capability	ion, lattice, coupling, experiment	605
	Y. Hidaka, B. Podobedov BNL, Upton, Long Island, New York, USA J. Bengtsson J B Optima, LLC, Rocky Point, USA
	Funding: The study is supported by U.S. DOE under Contract No. DE-AC02-98CH10886. A fast new linear lattice characterization / correction method based on turn-by-turn (TbT) beam position monitor (BPM) data in storage rings has been recently developed and experimentally demonstrated at NSLS-II. This method performs least-square fitting iteratively on the 4 frequency components extracted from TbT data and dispersion functions. The fitting parameters include the errors for normal/skew quadrupole strength and 4 types of BPM errors (gain, roll, and deformation). The computation of the Jacobian matrix for this system is very fast as it utilizes analytical expressions derived from the resonance driving terms (RDT), from which the method name DTBLOC (Driving-Terms-Based Linear Optics Characterization/Correction) originates. At NSLS-II, a lattice corrected with DTBLOC was estimated to have beta-beating of <1%, dispersion errors of ~1 mm, and emittance coupling ratio on the order of 10^-4.
	Poster TUPOB52 [2.206 MB]
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TUPOB60	Permanent Magnets for High Energy Nuclear Physics Accelerators	ion, electron, permanent-magnet, dipole	622
	N. Tsoupas, S.J. Brooks, A.K. Jain, F. Méot, V. Ptitsyn, D. Trbojevic BNL, Upton, Long Island, New York, USA
	Funding: Work supported by the US Department of Energy The proposed eRHIC accelerator1 will collide 20 GeV polarized electrons with 250 GeV polarized protons or 100 GeV/n polarized 3He ions or other unpolarized heavy ions. The electron accelerator of the eRHIC will be based on a 1.665 GeV Energy Recovery Linac (ERL) placed in the RHIC tunnel and two Fixed Field Alternating Gradient (FFAG) recirculating rings placed alongside the RHIC accelerator. The electron bunches reach the 20 GeV energy after passing 12 times through the ERL by recirculation in the FFAG rings. The FFAG rings consist of FODO cells comprised of one focusing and one defocusing quadrupoles made of permanent magnet material. Similarly other sections of the electron accelerator will utilize permanent magnets. In this presentation we will discuss details on the design of these magnets and their advantages over the current-excited magnets. 1. <http://arxiv.org/ftp/arxiv/papers/1409/1409.1633.pdf>
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WEPOA55	Modulator Simulations for Coherent Electron Cooling	ion, electron, simulation, plasma	816
	J. Ma, X. Wang SBU, Stony Brook, New York, USA V. Litvinenko, V. Samulyak, G. Wang, K. Yu BNL, Upton, Long Island, New York, USA V. Litvinenko Stony Brook University, Stony Brook, USA V. Samulyak SUNY SB, Stony Brook, New York, USA
	Highly resolved numerical simulations of the modulator, the first section of the proposed coherent electron cooling (CEC) device, have been performed using the code SPACE. The beam parameters for simulations are relevant to the Relativistic Heavy Ion Collider (RHIC) at Brookhaven National Laboratory (BNL). Numerical convergence has been studied using various numbers of macro-particles and mesh refinements of computational domain. A good agreement of theory and simulations has been obtained for the case of stationary and moving ions in uniform electron clouds with realistic distribution of thermal velocities. The main result of the paper is the prediction of modulation processes for ions with reference and off-reference coordinates in realistic Gaussian electron bunches with quadrupole field.
	Poster WEPOA55 [1.510 MB]
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WEB3IO02	First Test Results of the 150 mm Aperture IR Quadrupole Models for the High Luminosity LHC	ion, luminosity, dipole, alignment	853
	G. Ambrosio, G. Chlachidze Fermilab, Batavia, Illinois, USA P. Ferracin CERN, Geneva, Switzerland G.L. Sabbi LBNL, Berkeley, California, USA P. Wanderer BNL, Upton, Long Island, New York, USA
	Funding: Work supported by the US Department of Energy through the US LHC Accelerator Research Program (LARP) and by the High Luminosity LHC project at CERN. The High Luminosity upgrade of the LHC at CERN will use large aperture (150 mm) quadrupole magnets to focus the beams at the interaction points. The high field in the coils requires Nb3Sn superconductor technology, which has been brought to maturity by the LHC Accelerator Research Program (LARP) over the last 10 years. The key design targets for the new IR quadrupoles were established in 2012, and fabrication of model magnets started in 2014. This paper discusses the results from the first single short coil test and from the first short quadrupole model test. Remaining challenges and plans to address them are also presented and discussed.
	Slides WEB3IO02 [15.312 MB]
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WEPOB01	Lower Emittance Lattice for the Advanced Photon Source Upgrade Using Reverse Bending Magnets	ion, lattice, emittance, damping	877
	M. Borland, T.G. Berenc, R.R. Lindberg, V. Sajaev, Y.P. Sun ANL, Argonne, Illinois, USA
	Funding: Work supported by the U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences, under Contract No. DE-AC02-06CH11357. he Advanced Photon Source (APS) is pursuing an upgrade to the storage ring to a hybrid seven-bend-achromat design. The nominal design provides a natural emittance of 67 pm. By adding reverse dipole fields to several quadrupoles, we can reduce the natural emittance to 41 pm while simultaneously providing more optimal beta functions in the insertion devices. The improved emittance results from a combination of increased energy loss per turn and a change in the damping partition. At the same time, the nonlinear dynamics performance is very similar, thanks in part to increased dispersion in the sextupoles. This paper describes the properties, optimization, and performance of the new lattice. L. Farvacque et al., IPAC13, 79 (2013). ** J.P. Delahaye \em et al., PAC89, 1611 (1990); A. Streun, NIM A 737, 148 (2014).
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WEPOB03	Magnetic Measurements of Storage Ring Magnets for the APS Upgrade Project	ion, alignment, MMI, sextupole	884
	R.J. Dejus, H. Cease, J.T. Collins, G. Decker, A.T. Donnelly, C.L. Doose, W.G. Jansma, M.S. Jaski, J. Liu ANL, Argonne, Illinois, USA J. DiMarco Fermilab, Batavia, Illinois, USA A.K. Jain BNL, Upton, Long Island, New York, USA
	Funding: * Work supported by U.S. Department of Energy, Office of Science, under contract number DE-AC02-06CH11357, and contract number DE-SC0012704 for work associated with Brookhaven National Laboratory. Extensive prototyping of storage ring magnets is ongoing at the Advanced Photon Source (APS) in support of the APS Multi-Bend Achromat upgrade (APS-U) project. As part of the R&D activities 4 quadrupole magnets with slightly different geometries and pole tip materials, and one sextupole magnet with vanadium permendur pole tips were designed, built and tested. Magnets were measured individually using a rotating coil and a Hall probe for detailed mapping of the magnetic field. Magnets were then assembled and aligned relative to each other on a steel support plate and concrete plinth using precision machined surfaces to gain experience with the alignment method chosen for the APS-U storage ring magnets. The required alignment of magnets on a common support structure is 30 micron rms. Measurements of magnetic field quality, strength and magnet alignment after subjecting the magnets and assemblies to different tests will be presented.
	Poster WEPOB03 [1.242 MB]
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WEPOB09	Field Quality from Tolerance Stack Up in R&D Quadrupoles for the Advanced Photon Source Upgrade	ion, lattice, alignment, multipole	904
	J. Liu, M. Borland, R.J. Dejus, A.T. Donnelly, C.L. Doose, J.S. Downey, M.S. Jaski ANL, Argonne, Illinois, USA A.K. Jain BNL, Upton, Long Island, New York, USA
	Funding: *Work supported by U.S. Department of Energy, Office of Science, under contract No. DE-AC02-06CH11357 and contract number DE-SC0012704 for work associated with Brookhaven National Laboratory. The Advanced Photon Source (APS) at Argonne National Laboratory (ANL) is considering upgrading the current double-bend, 7-GeV, 3rd generation storage ring to a 6-GeV, 4th generation storage ring with a Multibend Achromat (MBA) lattice. In this study, a novel method is proposed to determine fabrication and assembly tolerances through a combination of magnetic and mechanical tolerance analyses. Mechanical tolerance stackup analyses using Teamcenter Variation Analysis are carried out to determine the part and assembly level fabrication tolerances. Finite element analyses using OPERA are conducted to estimate the effect of fabrication and assembly errors on the magnetic field of a quadrupole magnet and to determine the allowable tolerances to achieve the desired magnetic performance. Finally, results of measurements in R&D quadrupole prototypes are compared with the analysis results.
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WEPOB14	APS-U Lattice Design for Off-Axis Accumulation	ion, lattice, emittance, injection	920
	Y.P. Sun, M. Borland, R.R. Lindberg, V. Sajaev ANL, Argonne, Illinois, USA
	A 67-pm hybrid-seven-bend achromat (H7BA) lattice is being proposed for a future Advanced Photon Source (APS) multi-bend-achromat (MBA) upgrade project. This lattice design pushes for smaller emittance and requires use of a swap-out (on-axis) injection scheme due to limited dynamic acceptance. Alternate lattice design work has also been performed for the APS upgrade to achieve better beam dynamics performance than the nominal APS MBA lattice, in order to allow off-axis accumulation. Two such alternate H7BA lattice designs, which target a still-low emittance of 90 pm, are discussed in detail in this paper. Although the single-particle-dynamics performance is good, simulations of collective effects indicate that surprising difficulty would be expected accumulating high single-bunch charge in this lattice. The brightness of the 90-pm lattice is also a factor of two lower than the 67-pm H7BA lattice.
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WEPOB65	Experiments of Lossless Crossing - Resonance With Tune Modulation by Synchrotron Oscillations	ion, resonance, lattice, experiment	1036
	G.M. Wang, B. Holub, Y. Li, J. Rose, T.V. Shaftan, V.V. Smaluk BNL, Upton, Long Island, New York, USA
	It had become a standard practice to constrain particle's tune footprint while designing the storage ring lattice so that the tunes fit between harmful resonances that limit ring dynamic aperture (DA). However, in recent ultra-bright light source design, the nonlinearities of storage ring lattices are much enhanced as compared with the 3rd generation light source one. It is becoming more and more difficult to keep the off-momentum tune footprint confined and even more, the solution cannot be found to confine off-energy tune footprint in certain cases. The questions have been asked whether crossing of a resonance stopband from off-momentum particle will necessarily lead to particle loss. In NSLS-II, we modified the lattice working point to mimic machine tune footprint crossing half integer with beam synchrotron oscillation excitation and demonstrated that beam can cross a resonance without loss with control of stopband width and high order chromaticity.
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THA2IO02	High Gradient PM Technology for Ultra-High Brightness Rings	ion, storage-ring, HOM, radiation	1077
	G. Le Bec, J. Chavanne ESRF, Grenoble, France
	Permanent magnets have long been major components in accelerator-based light sources, particularly as a part of insertion devices. However, their use as main lattice magnets (dipoles, quadrupoles) has been so far somewhat limited. The present trend towards small magnet apertures, exemplified by various multibend achromat designs currently under commissioning or design/construction opens up the discussion once more on the large-scale use of permanent magnets as a means to achieve extremely high gradients in future diffraction-limited storage rings. This paper will review the current R&D programs on the use of permanent magnets in the lattice of high brightness storage rings.
	Slides THA2IO02 [5.770 MB]
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THPOA05	Intrabeam Scattering in High Brightness Electron Linacs	ion, electron, emittance, linac	1104
	S. Di Mitri Elettra-Sincrotrone Trieste S.C.p.A., Basovizza, Italy
	The role played by Intra-Beam Scattering (IBS) in high brightness electron linacs, like those driving free electron lasers, is studied analytically and with particle tracking. We found that IBS typically plays no significant role in the microbunching instability that develops in such accelerators. A partial damping of the instability through IBS is envisaged, however, with dedicated magnetic insertions. The feasibility of linear and circular lattice designs to cumulate relevant IBS-induced energy spread, and the interplay with microbunching instability, are discussed theoretically, and with the help of tracking codes. S. Di Mitri, PRST-AB 17, 074401 (2014)
	Poster THPOA05 [0.547 MB]
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THPOA07	Probablistic Estimation of Low Energy Electron Trapping in Quadrupoles	ion, electron, storage-ring, simulation	1112
	K.G. Sonnad KEK, Ibaraki, Japan J.A. Crittenden, K.G. Sonnad Cornell University (CLASSE), Cornell Laboratory for Accelerator-Based Sciences and Education, Ithaca, New York, USA
	Electron cloud formation in quadrupoles is important for storage rings because they have the potential of being trapped for a time period that exceeds the revolution period of the beam. This can result in a turn by turn build up of cloud, that could potentially interfere with beam motion. The mechanism of electron trapping can be understood based on dynamics associated with the motion of an isolated charged particle in a magnetic field. In such a system, energy is conserved and so is the magnetic moment of the gyrating electron which is an adiabatic invariant. This leads to determination of a so called loss cone in velocity space. Using these principles we describe a method to estimate the probability distribution of trapping across the cross-section of a quadrupole for a given field gradient and electron energy. Such an estimate can serve as a precursor to more detailed numerical studies of electron cloud build and trapping in quadrupoles.
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THPOA13	Modeling of Dipole and Quadrupole Fringe-Field Effects for the Advanced Photon Source Upgrade Lattice	ion, dipole, lattice, multipole	1119
	M. Borland, R.R. Lindberg ANL, Argonne, Illinois, USA
	Funding: Work supported by the U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences, under Contract No. DE-AC02-06CH11357. The proposed upgrade of the Advanced Photon Source (APS) to a multibend-achromat lattice requires shorter and much stronger quadrupole magnets than are present in the existing ring. This results in longitudinal gradient profiles that differ significantly from a hard-edge model. Additionally, the lattice assumes the use of five-segment longitudinal gradient dipoles. Under these circumstances, the effects of fringe fields and detailed field distributions are of interest. We evaluated the effect of soft-edge fringe fields on the linear optics and chromaticity, finding that compensation for these effects is readily accomplished. In addition, we evaluated the reliability of standard methods of simulating hard-edge nonlinear fringe effects in quadrupoles.
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THPOA61	A Possible Emittance Reduction Scheme for PLSII	ion, lattice, emittance, electron	1226
	T.-Y. Lee PAL, Pohang, Kyungbuk, Republic of Korea
	As the upgrade of PLS, PLSII is a 3 GeV light source in 12 super-periods (281.8 m circumference) with 5.8 nm design emittance and can store electron beam up to 400 mA with 3 superconducting RF cavities. PLSII lattice is a double bend achromatic (DBA) lattice with 2 straight sections for each cell (24 straight sections). After comple-tion of PLSII, multi-bend achromatic lattice has widely been adopted to accomplish low emittance. This paper discusses how a minimal change can modify the PLSII's DBA to a quadruple bend achromatic (QBA) lattice and reduce the emittance to about a half value.
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FRA1CO04	6D Phase Space Measurement of Low Energy, High Intensity Hadron Beam	ion, simulation, electron, emittance	1271
	B.L. Cathey ORNL RAD, Oak Ridge, Tennessee, USA A.V. Aleksandrov, S.M. Cousineau, A.P. Zhukov ORNL, Oak Ridge, Tennessee, USA
	Funding: SNS is managed by UT-Battelle, LLC, under contract DE-AC05-00OR22725 for the U.S. Department of Energy. The work has been partially supported by NSF grant 1535312 The goal of this project is to demonstrate a method for measuring the full 6D phase space of an low energy, high intensity hadron beam. This is done by combining 4D emittance measurement techniques along with dispersion measurement and a beam shape monitor to provide the energy and phase space components. The measurement will be performed on new Beam Testing Facility (BTF) at the Spallation Neutron Source (SNS), a 2.5 MeV functional duplicate of the SNS accelerator front end.
	Slides FRA1CO04 [8.295 MB]
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FRA2CO03	Study of the Electrical Center of a Resonant Cavity Beam Position Monitor (RF-BPM) and Its Integration With the Main Beam Quadrupole for Alignment Purposes	ion, cavity, alignment, scattering	1297
	S. Zorzetti, M. Wendt CERN, Geneva, Switzerland L. Fanucci Università di Pisa, Pisa, Italy
	To achieve the luminosity goals in a next generation linear collider, acceleration and preservation of ultra-low emittance particle beams is mission critical and requires a precise alignment between the main accelerator components. PACMAN is an innovative doctoral training program, hosted by CERN, with the goal of developing high accuracy metrology and alignment methods and tools to integrate those components in a standalone, automatic test bench. The method will be validated on CLIC components, a proposed Compact Linear Collider currently studied at CERN. The alignment between the electrical center of the Beam Position Monitor (BPM) and the magnetic center of the associated Main Beam Quadrupole (MBQ) is of particular importance to minimize the emittance blow-up, and therefore in the focus of the PACMAN project. The two components have been independently characterized on separated test benches by stretched and vibrating wire techniques. Preliminary conclusions are presented in this paper, with emphasis on the characterization of the electrical center of the BPM. The PACMAN project is funded by the European Union' s Seventh Framework Programme for research, technological development and demonstration under grant agreement no. 606839
	Slides FRA2CO03 [7.920 MB]
	Poster FRA2CO03 [1.570 MB]
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Paper

Title

Other Keywords

Page

MOB3CO04

High Luminosity 100 TeV Proton-Antiproton Collider

ion, proton, collider, antiproton

45

S.J. Oliveros, J.G. Acosta, L.M. Cremaldi, T.L. Hart, D.J. Summers
UMiss, University, Mississippi, USA

The energy scale for new physics is known to be in the multi-TeV range, signaling the potential need for a collider beyond the LHC. A 10³⁴ cm**−2 s**−1 luminosity 100 TeV proton-antiproton collider is explored. Prior engineering studies for 233 and 270 km circumference tunnels were done for Illinois dolomite and Texas chalk signaling manageable tunneling costs. At a ppbar the cross section for high mass states is of order 10x higher with antiproton collisions, where antiquarks are directly present rather than relying on gluon splitting. The higher cross sections reduce the synchrotron radiation in superconducting magnets, because lower beam currents can produce the same rare event rates. In our design the increased momentum acceptance (11 ± 2.6 GeV/c) in a Fermilab-like antiproton source is used with septa to collect 12x more antiprotons in 12 channels. For stochastic cooling, 12 cooling systems would be used, each with one debuncher/momentum equalizer ring and two accumulator rings. One electron cooling ring would follow. Finally antiprotons would be recycled during runs without leaving the collider ring, by joining them to new bunches with synchrotron damping.

Slides MOB3CO04 [1.304 MB]

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MOB4CO03

Design of Muon Collider Lattices

ion, collider, sextupole, factory

69

Y.I. Alexahin
Fermilab, Batavia, Illinois, USA

Funding: Work supported by Fermi Research Alliance, LLC under Contract DE-AC02-07CH11359 with the U.S. DOE
A Muon Collider promises unique opportunities both as an energy frontier machine and as a factory for detailed study of the Higgs boson and other particles. However, in order to achieve a competitive level of luminosity a number of demanding requirements to the collider optics should be satisfied arising from short muon lifetime and relatively large values of the transverse emittance and momentum spread in muon beams that can realistically be obtained with ionization cooling. Basic solutions which make possible to achieve these goals with Nb3Sn magnet parameters are presented.

Slides MOB4CO03 [0.794 MB]

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MOPOB40

Quench Training Analysis of Nb3Sn Accelerator Magnets

ion, dipole, operation, magnet-design

155

S. Stoynev, K.H. Riemer, A.V. Zlobin
Fermilab, Batavia, Illinois, USA

Funding: This work is supported by Fermi Research Alliance, LLC, under contract No. DE-AC02-07CH11359 with the U.S. Department of Energy.
Nb3Sn accelerator magnet technology has made significant progress during the past decades. Thanks to that 11-12 T Nb3Sn dipoles and quadrupoles are planned to be used in accelerators such as LHC in near future for the luminosity upgrade and in longer term for the LHC energy upgrade or a future Very High Energy pp Collider. However, all the state of the art Nb3Sn accelerator magnets show quite long training. This specific feature significantly raises the required design margin or limit the nominal operation field of Nb3Sn accelerator magnets and, thus, increases their cost. To resolve this problem Fermilab has launched a study aiming to analyze the relatively large amount of Nb3Sn magnet training data accumulated at Fermilab magnet test facility. The ultimate goal is to correlate magnet design and manufacturing features and magnet material properties with training performance parameters which will eventually allow us to optimize both the magnet design, fabrication and the training processes. This paper describes the general strategy of the analysis and presents the first results based on partial data processing. Conclusions and further steps are also outlined and discussed.

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MOPOB41

Field Quality Measurements in the FNAL Twin-Aperture 11 T Dipole for LHC Upgrades

ion, dipole, magnet-design, ion-effects

158

T. Strauss, G. Apollinari, E.Z. Barzi, G. Chlachidze, J. DiMarco, A. Nobrega, I. Novitski, S. Stoynev, D. Turrioni, G. Velev, A.V. Zlobin
Fermilab, Batavia, Illinois, USA
B. Auchmann, S. Izquierdo Bermudez, M. Karppinen, L. Rossi, F. Savary, D. Smekens
CERN, Geneva, Switzerland

Funding: *Work is supported by Fermi Research Alliance, LLC, under contract No. DE-AC02-07CH11359 with the U.S. Department of Energy and European Commission under FP7 project HiLumi LHC, GA no.284404
FNAL and CERN magnet groups are developing a twin-aperture Nb3Sn 11 T dipole suitable for installation in the LHC to provide room for additional collimators in the dispersion suppressor (DS) areas. Two of these magnets with a collimator in between will replace one regular MB dipole. A single-aperture 2-m long dipole demonstrator and two 1-m long dipole models have been assembled and tested at FNAL in 2012-2014. The 1 m long collared coils were then assembled into the twin-aperture configuration and tested in 2015. The first magnet test was focused on the quench performance of twin-aperture magnet configuration including magnet training, ramp rate sensitivity and temperature dependence of magnet quench current. In the second test performed in July 2016 field quality in one of the two magnet apertures has been measured and compared with the data for the single-aperture models. These results are reported and discussed in this paper.

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MOPOB54

Superferric Arc Dipoles for the Ion Ring and Booster of JLEIC

ion, dipole, multipole, collider

184

P.M. McIntyre, J. Breitschopf, T. Elliott, R. Garrison, J. Gerity, J.N. Kellams, A. Sattarov
Texas A&M University, College Station, USA
D. Chavez
DCI-UG, León, Mexico

Funding: This work was supported by a grant from the NP Division of the US Dept. of Energy.
The JLEIC project requires 3 T superferric dipoles and quadrupoles for the half-cell arcs of its Ion Ring and Booster. A superferric design using NbTi cable-in-conduit conductor is being developed. A mockup winding has been completed, with the objectives to develop and evaluate the coil structure and the winding tooling and methods, and to measure errors in the position of each cable turn in the dipole body. The results of the mockup winding study are presented. The CIC design is now ready for construction and testing of a first model dipole.

Poster MOPOB54 [1.147 MB]

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MOPOB55

Room Temperature Magnets in FRIB Driver Linac

ion, linac, alignment, dipole

188

Y. Yamazaki, N.K. Bultman, E.E. Burkhardt, F. Feyzi, K. Holland, A. Hussain, M. Ikegami, F. Marti, S.J. Miller, T. Russo, J. Wei, Q. Zhao
FRIB, East Lansing, USA
W.J. Yang, Q.G. Yao
IMP/CAS, Lanzhou, People's Republic of China

Funding: Work supported by the U.S. Department of Energy Office of Science under Cooperative Agreement DE-SC0000661 and the National Science Foundation under Cooperative Agreement PHY-1102511.
The FRIB Driver Linac* is to accelerate all the stable ions beyond 200 MeV/nucleon with a beam power of 400 kW. The linac is unique, being compactly folded twice. In this report, the room temperature magnets, amounting 147 in total, after Front End with a 0.5-MeV RFQ, are detailed, emphasizing the rotating coil field measurements and fiducialization.
*E. Pozdeyev et al., "Status of FRIB" in this conference.
T. Xu, "Superconducting Cryomodule Development and Production for the FRIB Linac" in this conference.

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MOPOB59

Magnet Design for the Splitter/Combiner Regions of CBETA, the Cornell-Brookhaven Energy-Recovery-Linac Test Accelerator

ion, dipole, linac, magnet-design

201

J.A. Crittenden, D.C. Burke, Y.L.P. Fuentes, C.E. Mayes, K.W. Smolenski
Cornell University (CLASSE), Cornell Laboratory for Accelerator-Based Sciences and Education, Ithaca, New York, USA

Funding: Supported by NSF award DMR-0807731, DOE grant DE-AC02-76SF00515, and New York State.
The Cornell-Brookhaven Energy-Recovery-Linac Test Accelerator (CBETA) will provide a 150-MeV electron beam using four acceleration and four deceleration passes through the Cornell Main Linac Cryomodule housing six 1.3-GHz superconducting RF cavities. The return path of this 76-m-circumference accelerator will be provided by 10⁶ fixed-field alternating-gradient (FFAG) cells which carry the four beams of 42, 78, 114 and 150-MeV. Here we describe magnet designs for the splitter and combiner regions which serve to match the on-axis linac beam to the off-axis beams in the FFAG cells, providing the path-length adjustment necessary to energy recovery for each of the four beams. The path lengths of the four beamlines in each of the splitter and combiner regions are designed to be adapted to 1-, 2-, 3-, and 4-pass staged operations. Design specifications and modeling for the 24 dipole and 32 quadrupole electromagnets in each region are presented. The CBETA project will serve as the first demonstration of multi-pass energy recovery using superconducting RF cavities with FFAG cell optics for the return loop.

Poster MOPOB59 [8.982 MB]

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TUPOA36

Computed Tomography of Transverse Phase Space

ion, simulation, instrumentation, optics

358

A.C. Watts, C. Johnstone, J.A. Johnstone
Fermilab, Batavia, Illinois, USA

Funding: Work supported by Fermi Reserach Alliance, LLC under Contract no. DE-AC02-07CH11359 with the United States Department of Energy.
Two computed tomography techniques are explored to reconstruct beam transverse phase space using both simulated beam and multi-wire profile data in the Fermilab Muon Test Area ("MTA") beamline. Both Filtered Back-Projection ("FBP") and Simultaneous Algebraic Reconstruction Technique ("SART") algorithms are considered and compared. Errors and artifacts are compared as a function of each algorithm's free parameters, and it is shown through simulation and MTA beamline profiles that SART is advantageous for reconstructions with limited profile data.
awatts@fnal.gov, cjj@fnal.gov, jjohnstone@fnal.gov

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TUPOA46

Development of a Python-Based Emittance Calculator at Fermilab Science & Technology (FAST) Facility

emittance, ion, experiment, solenoid

376

A.T. Green
Northern Illinois Univerity, DeKalb, Illinois, USA
Y.-M. Shin
Fermilab, Batavia, Illinois, USA
Y.-M. Shin
Northern Illinois University, DeKalb, Illinois, USA

Beam emittance is an important characteristic which helps to describe a charged particle beam. In linear accelerators (linac), it is critical to characterize the beam phase space parameters and, in particular, to precisely measure transverse beam emittance. The quadrupole scan (quad-scan) is a well established technique used to characterize transverse beam parameters in four-dimensional phase space. Quad-scans are very time consuming and off-line analysis is needed to extrapolate the beam phase space parameters. We have developed a computational algorithm with Python scripts to automatically estimate beam parameters, in particular beam emittance, using the quadrupole scan technique in the electron linac of Fermilab Accelerator Science and Technology (FAST) facility. These Python scripts have decreased the time it takes to perform a single quad scan from a few hours to a few minutes. From the experimental data, the emittance calculator quickly delivers various results including: transverse emittance, Courant-Snyder parameters, and Beam Size (squared) vs Quadrupole field strength plots, among others.

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TUPOA48

A High-Level Python Interface to the Fermilab ACNET Control System

ion, controls, emittance, interface

383

P. Piot
Fermilab, Batavia, Illinois, USA
A. Halavanau
Northern Illinois University, DeKalb, Illinois, USA

This paper discusses the implementation of a PYTHON-based high-level interface to the Fermilab ACNET control system. We will especially present examples of applications which include the interfacing of an ELEGANT beam-dynamics model to assist lattice matching and an automated emittance measurement via the quadrupole-scan method.

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TUB4CO04

Progress on the Magnetic Performance of Planar Superconducting Undulators

ion, undulator, photon, octupole

477

M. Kasa, C.L. Doose, J.D. Fuerst, E. Gluskin, Y. Ivanyushenkov
ANL, Argonne, Illinois, USA

Funding: Work supported by the U.S. Department of Energy, Office of Science, under Contract No. DE-AC02-06CH11357.
One of the primary goals of the superconducting undulator (SCU) program at the Advanced Photon Source (APS) is to achieve a high quality undulator magnetic field without the need for magnetic shimming to tune the device. Over the course of two years, two SCUs were designed, manufactured, assembled, and tested at the APS. Both SCUs were one meter in length with a period of 1.8 cm. After magnetic measurements of the first undulator were completed, several design changes were made in order to improve the quality of the undulator magnetic field. The design modifications were implemented during construction and assembly of the second SCU. The details of the design modifications along with a comparison of the magnetic measurement results will be described.

Slides TUB4CO04 [6.426 MB]

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TUPOB11

Quantification of Octupole Magnets at the University of Maryland Electron Ring

ion, octupole, multipole, lattice

503

H. Baumgartner, B. Beaudoin, S. Bernal, I. Haber, T.W. Koeth, D.B. Matthew, K.J. Ruisard, M.R. Teperman
UMD, College Park, Maryland, USA

Funding: Funding for this project is provided by DOE-HEP and the NSF Accelerator Science Program
The intensity frontier is limited by the ability to propagate substantial amounts of beam current without resulting in particle scrapping and/or losses from resonant growth and halo formation. Modern accelerators are based on the theories developed in the 1950's that assume particle motion is bounded and subject to linear forces. Recent theoretical developments have demonstrated that a strongly nonlinear lattice can be used to stably transport an intense beam has resulted in a fundamental rethinking of the conventional wisdom. A lattice composed of strong nonlinear magnets is predicted by theory to damp resonances while maintaining dynamic aperture. Results of rotating coil measurements, magnetic field scans and simulations will be presented, quantifying the multi-pole moments and fringe fields in the 1st generation Printed Circuit Board (PCB) octupoles for UMER's nonlinear lattice experiments.

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TUPOB12

Experimental Plans for Single-Channel Strong Octupole Fields at the University of Maryland Electron Ring

ion, lattice, octupole, focusing

507

K.J. Ruisard, H. Baumgartner, B. Beaudoin, I. Haber, T.W. Koeth, M.R. Teperman
UMD, College Park, Maryland, USA

Funding: Funding for this project and travel is provided by DOE-HEP, NSF GRFP and NSF Accelerator Science Program
Nonlinear quasi-integrable optics is a promising development on the horizon of high-intensity ring design. Large amplitude-dependent tune spreads, driven by strong nonlinear magnet inserts, lead to decoupling from incoherent tune resonances. This reduces intensity-driven beam loss while quasi-integrability ensures a well-contained beam. In this paper we discuss on-going work to install and interrogate a long-octupole channel at the University of Maryland Electron Ring (UMER). This is a discrete insert that occupies 20 degrees of the ring, consisting of independently powered printed circuit octupole magnets. Transverse confinement is obtained with quadrupoles external to this insert. Operating UMER as a non-FODO lattice, in order to meet the beam-envelope requirements of the quasi-integrable lattice, is a challenge. We discuss efforts to match the beam and optimize steering solutions. We also discuss our experiences operating a distributed strong octupole lattice.

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TUPOB26

Dynamics of Intense Beam in Quadrupole-Duodecapole Lattice Near Sixth Order Resonance

ion, resonance, focusing, lattice

552

Y.K. Batygin, T.T. Fronk
LANL, Los Alamos, New Mexico, USA

Funding: Work supported by US DOE under contract DE-AC52-06NA25396
The presence of duodecapole components in quadrupole focusing field results in excitation of sixth-order single-particle resonance if the phase advance of the particles transverse oscillation is close to 60 deg. This phenomenon results in intensification of beam losses. We present analytical and numerical treatment of particle dynamics in the vicinity of sixth-order resonance. The topology of resonance in phase space is analyzed. Beam emittance growth due to crossing of resonance islands is determined. Halo formation of intense beams in presence of resonance conditions is examined.

Poster TUPOB26 [3.523 MB]

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TUPOB37

Diffusion Measurement From Transverse Echoes

ion, dipole, simulation, octupole

572

Y.S. Li
Carleton College, Northfield, Minnesota, USA

Beam diffusion is an important measure of stability in high intensity beams. Traditional methods of diffusion characterization (e.g. beam scraping) can be very time-consuming. In this study, we investigate the transverse beam echo as a novel technique for measuring beam diffusion. Numerical analysis of maximum echo amplitude was compared with theoretical predictions with and without diffusion. We succeeded in performing a self-consistent measurement of the linear diffusion coefficient via a parameter scan over delay time. We also demonstrated the effectiveness of pulsed quadrupoles as a means to boost echo amplitude. Finally, multi-echo sequences were also briefly investigated. Results from this study will support planned experiments at the IOTA proton ring under construction at Fermilab.

Poster TUPOB37 [2.109 MB]

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TUPOB44

Final 6d Muon Ionization Cooling Using Strong Focusing Quadrupoles

ion, emittance, betatron, collider

592

T.L. Hart, J.G. Acosta, L.M. Cremaldi, S.J. Oliveros, D.J. Summers
UMiss, University, Mississippi, USA
D.V. Neuffer
Fermilab, Batavia, Illinois, USA

Low emittance muon beam lines and muon colliders are potentially a rich source of BSM physics for future experimenters. A normalized transverse muon emittance of 280 microns has been achieved in simulation with short solenoids and a betatron function of 3 cm. Here we use ICOOL, G4Beamline, and MAD-X to explore using a flat 400 MeV/c muon beam and strong focusing quadrupoles to achieve a normalized transverse emittance of 100 microns and finish 6D cooling. The low beta regions, as low as 5 mm, produced by the quadrupoles are occupied by dense, low Z absorbers, such as lithium hydride or beryllium, that cool the beam. Equilibrium transverse emittance is linearly proportional to the beta function. Reverse emittance exchange with septa and/or wedges is then used to decrease transverse emittance from 100 to 25 microns at the expense of longitudinal emittance for a high energy lepton collider. Cooling challenges include chromaticity correction, momentum passband overlap, quadrupole acceptance, and staying in phase with RF.

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TUPOB52

Linear Optics Characterization and Correction Method Using Turn-By-Turn BPM Data Based on Resonance Driving Terms with Simultaneous BPM Calibration Capability

ion, lattice, coupling, experiment

605

Y. Hidaka, B. Podobedov
BNL, Upton, Long Island, New York, USA
J. Bengtsson
J B Optima, LLC, Rocky Point, USA

Funding: The study is supported by U.S. DOE under Contract No. DE-AC02-98CH10886.
A fast new linear lattice characterization / correction method based on turn-by-turn (TbT) beam position monitor (BPM) data in storage rings has been recently developed and experimentally demonstrated at NSLS-II. This method performs least-square fitting iteratively on the 4 frequency components extracted from TbT data and dispersion functions. The fitting parameters include the errors for normal/skew quadrupole strength and 4 types of BPM errors (gain, roll, and deformation). The computation of the Jacobian matrix for this system is very fast as it utilizes analytical expressions derived from the resonance driving terms (RDT), from which the method name DTBLOC (Driving-Terms-Based Linear Optics Characterization/Correction) originates. At NSLS-II, a lattice corrected with DTBLOC was estimated to have beta-beating of <1%, dispersion errors of ~1 mm, and emittance coupling ratio on the order of 10^-4.

Poster TUPOB52 [2.206 MB]

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TUPOB60

Permanent Magnets for High Energy Nuclear Physics Accelerators

ion, electron, permanent-magnet, dipole

622

N. Tsoupas, S.J. Brooks, A.K. Jain, F. Méot, V. Ptitsyn, D. Trbojevic
BNL, Upton, Long Island, New York, USA

Funding: Work supported by the US Department of Energy
The proposed eRHIC accelerator1 will collide 20 GeV polarized electrons with 250 GeV polarized protons or 100 GeV/n polarized 3He ions or other unpolarized heavy ions. The electron accelerator of the eRHIC will be based on a 1.665 GeV Energy Recovery Linac (ERL) placed in the RHIC tunnel and two Fixed Field Alternating Gradient (FFAG) recirculating rings placed alongside the RHIC accelerator. The electron bunches reach the 20 GeV energy after passing 12 times through the ERL by recirculation in the FFAG rings. The FFAG rings consist of FODO cells comprised of one focusing and one defocusing quadrupoles made of permanent magnet material. Similarly other sections of the electron accelerator will utilize permanent magnets. In this presentation we will discuss details on the design of these magnets and their advantages over the current-excited magnets.
1. <http://arxiv.org/ftp/arxiv/papers/1409/1409.1633.pdf>

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WEPOA55

Modulator Simulations for Coherent Electron Cooling

ion, electron, simulation, plasma

816

J. Ma, X. Wang
SBU, Stony Brook, New York, USA
V. Litvinenko, V. Samulyak, G. Wang, K. Yu
BNL, Upton, Long Island, New York, USA
V. Litvinenko
Stony Brook University, Stony Brook, USA
V. Samulyak
SUNY SB, Stony Brook, New York, USA

Highly resolved numerical simulations of the modulator, the first section of the proposed coherent electron cooling (CEC) device, have been performed using the code SPACE. The beam parameters for simulations are relevant to the Relativistic Heavy Ion Collider (RHIC) at Brookhaven National Laboratory (BNL). Numerical convergence has been studied using various numbers of macro-particles and mesh refinements of computational domain. A good agreement of theory and simulations has been obtained for the case of stationary and moving ions in uniform electron clouds with realistic distribution of thermal velocities. The main result of the paper is the prediction of modulation processes for ions with reference and off-reference coordinates in realistic Gaussian electron bunches with quadrupole field.

Poster WEPOA55 [1.510 MB]

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WEB3IO02

First Test Results of the 150 mm Aperture IR Quadrupole Models for the High Luminosity LHC

ion, luminosity, dipole, alignment

853

G. Ambrosio, G. Chlachidze
Fermilab, Batavia, Illinois, USA
P. Ferracin
CERN, Geneva, Switzerland
G.L. Sabbi
LBNL, Berkeley, California, USA
P. Wanderer
BNL, Upton, Long Island, New York, USA

Funding: Work supported by the US Department of Energy through the US LHC Accelerator Research Program (LARP) and by the High Luminosity LHC project at CERN.
The High Luminosity upgrade of the LHC at CERN will use large aperture (150 mm) quadrupole magnets to focus the beams at the interaction points. The high field in the coils requires Nb3Sn superconductor technology, which has been brought to maturity by the LHC Accelerator Research Program (LARP) over the last 10 years. The key design targets for the new IR quadrupoles were established in 2012, and fabrication of model magnets started in 2014. This paper discusses the results from the first single short coil test and from the first short quadrupole model test. Remaining challenges and plans to address them are also presented and discussed.

Slides WEB3IO02 [15.312 MB]

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WEPOB01

Lower Emittance Lattice for the Advanced Photon Source Upgrade Using Reverse Bending Magnets

ion, lattice, emittance, damping

877

M. Borland, T.G. Berenc, R.R. Lindberg, V. Sajaev, Y.P. Sun
ANL, Argonne, Illinois, USA

Funding: Work supported by the U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences, under Contract No. DE-AC02-06CH11357.
he Advanced Photon Source (APS) is pursuing an upgrade to the storage ring to a hybrid seven-bend-achromat design*. The nominal design provides a natural emittance of 67 pm. By adding reverse dipole fields to several quadrupoles**, we can reduce the natural emittance to 41 pm while simultaneously providing more optimal beta functions in the insertion devices. The improved emittance results from a combination of increased energy loss per turn and a change in the damping partition. At the same time, the nonlinear dynamics performance is very similar, thanks in part to increased dispersion in the sextupoles. This paper describes the properties, optimization, and performance of the new lattice.
* L. Farvacque et al., IPAC13, 79 (2013).
** J.P. Delahaye \em et al., PAC89, 1611 (1990); A. Streun, NIM A 737, 148 (2014).

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WEPOB03

Magnetic Measurements of Storage Ring Magnets for the APS Upgrade Project

ion, alignment, MMI, sextupole

884

R.J. Dejus, H. Cease, J.T. Collins, G. Decker, A.T. Donnelly, C.L. Doose, W.G. Jansma, M.S. Jaski, J. Liu
ANL, Argonne, Illinois, USA
J. DiMarco
Fermilab, Batavia, Illinois, USA
A.K. Jain
BNL, Upton, Long Island, New York, USA

Funding: * Work supported by U.S. Department of Energy, Office of Science, under contract number DE-AC02-06CH11357, and contract number DE-SC0012704 for work associated with Brookhaven National Laboratory.
Extensive prototyping of storage ring magnets is ongoing at the Advanced Photon Source (APS) in support of the APS Multi-Bend Achromat upgrade (APS-U) project. As part of the R&D activities 4 quadrupole magnets with slightly different geometries and pole tip materials, and one sextupole magnet with vanadium permendur pole tips were designed, built and tested. Magnets were measured individually using a rotating coil and a Hall probe for detailed mapping of the magnetic field. Magnets were then assembled and aligned relative to each other on a steel support plate and concrete plinth using precision machined surfaces to gain experience with the alignment method chosen for the APS-U storage ring magnets. The required alignment of magnets on a common support structure is 30 micron rms. Measurements of magnetic field quality, strength and magnet alignment after subjecting the magnets and assemblies to different tests will be presented.

Poster WEPOB03 [1.242 MB]

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WEPOB09

Field Quality from Tolerance Stack Up in R&D Quadrupoles for the Advanced Photon Source Upgrade

ion, lattice, alignment, multipole

904

J. Liu, M. Borland, R.J. Dejus, A.T. Donnelly, C.L. Doose, J.S. Downey, M.S. Jaski
ANL, Argonne, Illinois, USA
A.K. Jain
BNL, Upton, Long Island, New York, USA

Funding: *Work supported by U.S. Department of Energy, Office of Science, under contract No. DE-AC02-06CH11357 and contract number DE-SC0012704 for work associated with Brookhaven National Laboratory.
The Advanced Photon Source (APS) at Argonne National Laboratory (ANL) is considering upgrading the current double-bend, 7-GeV, 3rd generation storage ring to a 6-GeV, 4th generation storage ring with a Multibend Achromat (MBA) lattice. In this study, a novel method is proposed to determine fabrication and assembly tolerances through a combination of magnetic and mechanical tolerance analyses. Mechanical tolerance stackup analyses using Teamcenter Variation Analysis are carried out to determine the part and assembly level fabrication tolerances. Finite element analyses using OPERA are conducted to estimate the effect of fabrication and assembly errors on the magnetic field of a quadrupole magnet and to determine the allowable tolerances to achieve the desired magnetic performance. Finally, results of measurements in R&D quadrupole prototypes are compared with the analysis results.

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WEPOB14

APS-U Lattice Design for Off-Axis Accumulation

ion, lattice, emittance, injection

920

Y.P. Sun, M. Borland, R.R. Lindberg, V. Sajaev
ANL, Argonne, Illinois, USA

A 67-pm hybrid-seven-bend achromat (H7BA) lattice is being proposed for a future Advanced Photon Source (APS) multi-bend-achromat (MBA) upgrade project. This lattice design pushes for smaller emittance and requires use of a swap-out (on-axis) injection scheme due to limited dynamic acceptance. Alternate lattice design work has also been performed for the APS upgrade to achieve better beam dynamics performance than the nominal APS MBA lattice, in order to allow off-axis accumulation. Two such alternate H7BA lattice designs, which target a still-low emittance of 90 pm, are discussed in detail in this paper. Although the single-particle-dynamics performance is good, simulations of collective effects indicate that surprising difficulty would be expected accumulating high single-bunch charge in this lattice. The brightness of the 90-pm lattice is also a factor of two lower than the 67-pm H7BA lattice.

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WEPOB65

Experiments of Lossless Crossing - Resonance With Tune Modulation by Synchrotron Oscillations

ion, resonance, lattice, experiment

1036

G.M. Wang, B. Holub, Y. Li, J. Rose, T.V. Shaftan, V.V. Smaluk
BNL, Upton, Long Island, New York, USA

It had become a standard practice to constrain particle's tune footprint while designing the storage ring lattice so that the tunes fit between harmful resonances that limit ring dynamic aperture (DA). However, in recent ultra-bright light source design, the nonlinearities of storage ring lattices are much enhanced as compared with the 3rd generation light source one. It is becoming more and more difficult to keep the off-momentum tune footprint confined and even more, the solution cannot be found to confine off-energy tune footprint in certain cases. The questions have been asked whether crossing of a resonance stopband from off-momentum particle will necessarily lead to particle loss. In NSLS-II, we modified the lattice working point to mimic machine tune footprint crossing half integer with beam synchrotron oscillation excitation and demonstrated that beam can cross a resonance without loss with control of stopband width and high order chromaticity.

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THA2IO02

High Gradient PM Technology for Ultra-High Brightness Rings

ion, storage-ring, HOM, radiation

1077

G. Le Bec, J. Chavanne
ESRF, Grenoble, France

Permanent magnets have long been major components in accelerator-based light sources, particularly as a part of insertion devices. However, their use as main lattice magnets (dipoles, quadrupoles) has been so far somewhat limited. The present trend towards small magnet apertures, exemplified by various multibend achromat designs currently under commissioning or design/construction opens up the discussion once more on the large-scale use of permanent magnets as a means to achieve extremely high gradients in future diffraction-limited storage rings. This paper will review the current R&D programs on the use of permanent magnets in the lattice of high brightness storage rings.

Slides THA2IO02 [5.770 MB]

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THPOA05

Intrabeam Scattering in High Brightness Electron Linacs

ion, electron, emittance, linac

1104

S. Di Mitri
Elettra-Sincrotrone Trieste S.C.p.A., Basovizza, Italy

The role played by Intra-Beam Scattering (IBS) in high brightness electron linacs, like those driving free electron lasers, is studied analytically and with particle tracking. We found that IBS typically plays no significant role in the microbunching instability that develops in such accelerators*. A partial damping of the instability through IBS is envisaged, however, with dedicated magnetic insertions. The feasibility of linear and circular lattice designs to cumulate relevant IBS-induced energy spread, and the interplay with microbunching instability, are discussed theoretically, and with the help of tracking codes.
* S. Di Mitri, PRST-AB 17, 074401 (2014)

Poster THPOA05 [0.547 MB]

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THPOA07

Probablistic Estimation of Low Energy Electron Trapping in Quadrupoles

ion, electron, storage-ring, simulation

1112

K.G. Sonnad
KEK, Ibaraki, Japan
J.A. Crittenden, K.G. Sonnad
Cornell University (CLASSE), Cornell Laboratory for Accelerator-Based Sciences and Education, Ithaca, New York, USA

Electron cloud formation in quadrupoles is important for storage rings because they have the potential of being trapped for a time period that exceeds the revolution period of the beam. This can result in a turn by turn build up of cloud, that could potentially interfere with beam motion. The mechanism of electron trapping can be understood based on dynamics associated with the motion of an isolated charged particle in a magnetic field. In such a system, energy is conserved and so is the magnetic moment of the gyrating electron which is an adiabatic invariant. This leads to determination of a so called loss cone in velocity space. Using these principles we describe a method to estimate the probability distribution of trapping across the cross-section of a quadrupole for a given field gradient and electron energy. Such an estimate can serve as a precursor to more detailed numerical studies of electron cloud build and trapping in quadrupoles.

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THPOA13

Modeling of Dipole and Quadrupole Fringe-Field Effects for the Advanced Photon Source Upgrade Lattice

ion, dipole, lattice, multipole

1119

M. Borland, R.R. Lindberg
ANL, Argonne, Illinois, USA

Funding: Work supported by the U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences, under Contract No. DE-AC02-06CH11357.
The proposed upgrade of the Advanced Photon Source (APS) to a multibend-achromat lattice requires shorter and much stronger quadrupole magnets than are present in the existing ring. This results in longitudinal gradient profiles that differ significantly from a hard-edge model. Additionally, the lattice assumes the use of five-segment longitudinal gradient dipoles. Under these circumstances, the effects of fringe fields and detailed field distributions are of interest. We evaluated the effect of soft-edge fringe fields on the linear optics and chromaticity, finding that compensation for these effects is readily accomplished. In addition, we evaluated the reliability of standard methods of simulating hard-edge nonlinear fringe effects in quadrupoles.

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THPOA61

A Possible Emittance Reduction Scheme for PLSII

ion, lattice, emittance, electron

1226

T.-Y. Lee
PAL, Pohang, Kyungbuk, Republic of Korea

As the upgrade of PLS, PLSII is a 3 GeV light source in 12 super-periods (281.8 m circumference) with 5.8 nm design emittance and can store electron beam up to 400 mA with 3 superconducting RF cavities. PLSII lattice is a double bend achromatic (DBA) lattice with 2 straight sections for each cell (24 straight sections). After comple-tion of PLSII, multi-bend achromatic lattice has widely been adopted to accomplish low emittance. This paper discusses how a minimal change can modify the PLSII's DBA to a quadruple bend achromatic (QBA) lattice and reduce the emittance to about a half value.

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FRA1CO04

6D Phase Space Measurement of Low Energy, High Intensity Hadron Beam

ion, simulation, electron, emittance

1271

B.L. Cathey
ORNL RAD, Oak Ridge, Tennessee, USA
A.V. Aleksandrov, S.M. Cousineau, A.P. Zhukov
ORNL, Oak Ridge, Tennessee, USA

Funding: SNS is managed by UT-Battelle, LLC, under contract DE-AC05-00OR22725 for the U.S. Department of Energy. The work has been partially supported by NSF grant 1535312
The goal of this project is to demonstrate a method for measuring the full 6D phase space of an low energy, high intensity hadron beam. This is done by combining 4D emittance measurement techniques along with dispersion measurement and a beam shape monitor to provide the energy and phase space components. The measurement will be performed on new Beam Testing Facility (BTF) at the Spallation Neutron Source (SNS), a 2.5 MeV functional duplicate of the SNS accelerator front end.

Slides FRA1CO04 [8.295 MB]

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FRA2CO03

Study of the Electrical Center of a Resonant Cavity Beam Position Monitor (RF-BPM) and Its Integration With the Main Beam Quadrupole for Alignment Purposes

ion, cavity, alignment, scattering

1297

S. Zorzetti, M. Wendt
CERN, Geneva, Switzerland
L. Fanucci
Università di Pisa, Pisa, Italy

To achieve the luminosity goals in a next generation linear collider, acceleration and preservation of ultra-low emittance particle beams is mission critical and requires a precise alignment between the main accelerator components. PACMAN is an innovative doctoral training program, hosted by CERN, with the goal of developing high accuracy metrology and alignment methods and tools to integrate those components in a standalone, automatic test bench. The method will be validated on CLIC components, a proposed Compact Linear Collider currently studied at CERN. The alignment between the electrical center of the Beam Position Monitor (BPM) and the magnetic center of the associated Main Beam Quadrupole (MBQ) is of particular importance to minimize the emittance blow-up, and therefore in the focus of the PACMAN project. The two components have been independently characterized on separated test benches by stretched and vibrating wire techniques. Preliminary conclusions are presented in this paper, with emphasis on the characterization of the electrical center of the BPM.
The PACMAN project is funded by the European Union' s Seventh Framework Programme for research, technological development and demonstration under grant agreement no. 606839

Slides FRA2CO03 [7.920 MB]

Poster FRA2CO03 [1.570 MB]

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