Paper | Title | Page |
---|---|---|
TUPLO01 | Dual-Function Electron Ring-Ion Booster Design for JLEIC High-Energy Option | 529 |
SUPLH10 | use link to see paper's listing under its alternate paper code | |
|
||
Funding: This work was supported by the U.S. DOE, Office of Nuclear Physics, under Contract No. DE-AC02-06CH11357 for ANL and by Jefferson Science Associates, LLC under U.S. DOE Contract No. DE-AC05-06OR23177. As part of the alternative design approach for the Jeffer-son Laboratory Electron-Ion Collider (JLEIC) ion com-plex, the electron storage ring (e-ring) is consolidated to also serve as a large booster for the ions. The goal of reaching 16 GeV/u or higher for all ions using only room-temperature magnets forces the re-design of the e-ring because of magnetic field and lattice limitations. The new design is challenging due to several imposed constraints: (1) use of room-temperature magnets, (2) avoiding transi-tion crossing, and (3) maintaining the size and shape of the original e-ring design as much as possible. A design study is presented for a 16 GeV/u large ion booster after analyzing different alternatives that use: (1) combined-function magnets, (2) large quadrupoles or (3) quadrupole doublets in the lattice design. This design boosts the injection energy to the collider ring from 8 GeV (proton-equivalent) in the original baseline design to 16 GeV/u for all ions which is beneficial for the high-energy option of JLEIC of 200 GeV or higher. A scheme for adapting the new large ion booster design to also serve as electron storage ring is presented. |
||
DOI • | reference for this paper ※ https://doi.org/10.18429/JACoW-NAPAC2019-TUPLO01 | |
About • | paper received ※ 28 August 2019 paper accepted ※ 05 September 2019 issue date ※ 08 October 2019 | |
Export • | reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml) | |
TUPLO02 | Spin Dynamics in the JLEIC Ion Injector Linac | 533 |
SUPLH11 | use link to see paper's listing under its alternate paper code | |
|
||
Funding: This work was supported by the U.S. DOE, Office of Nuclear Physics, under Contract No. DE-AC02-06CH11357 for ANL and by Jefferson Science Associates, LLC under U.S. DOE Contract No. DE-AC05-06OR23177. One of the requirements for the future Electron Ion Col-lider (EIC) is to collide polarized electrons and light ions with at least 70% polarization for each beam. For light ions, polarized ion sources are used for injection to a linac, which is usually the first accelerator in the collider chain. The Jefferson Lab EIC (JLEIC) ion injector linac consists of a low-energy room-temperature section with quadrupole focusing followed by a superconducting linac with solenoid focusing inside long cryomodules. These two sections have different effects on the spin. Spin dy-namics simulation studies are carried out for the JLEIC injector linac in order to preserve and maintain a high degree of polarization for light ion beams for delivery to the booster. The different options to maintain and restore the spin in the different sections of the linac for hydrogen, deuterium and helium ions are presented and discussed. Results from both the Zgoubi and COSY-Infinity codes are presented and compared for every section of the ion linac but the radio-frequency quadrupole (RFQ). Current-ly, a method to simulate the RFQ using Zgoubi is being investigated. |
||
DOI • | reference for this paper ※ https://doi.org/10.18429/JACoW-NAPAC2019-TUPLO02 | |
About • | paper received ※ 28 August 2019 paper accepted ※ 19 November 2019 issue date ※ 08 October 2019 | |
Export • | reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml) | |
TUPLO03 | RHIC Beam Abort System Upgrade Options | 536 |
|
||
Funding: Work supported by U.S. DOE under contract No DE-AC02-98CH10886 with the U.S. Department of Energy. The RHIC ion (polarized proton) beam intensity has increased to 4x (1.1x) of the original design specifications. In 2013 proton beam currents overcame the eddy current reduction design features in the RHIC beam abort system kicker magnets causing ferrite heating and resulting in a reduction of the kicker strength. In 2014, the abort kicker ferrites were changed, the eddy current reduction design was upgraded, and an active ferrite cooling loop installed to prevent heating. For ions the beam dump vacuum window was changed from stainless steel to a titanium alloy and the adjacent beam diffuser block carbon material was changed to allow for higher ion intensities. A thicker beam pipe was installed to prevent secondaries from quenching the adjacent superconducting quadrupole. With these upgrades there is at least a factor 2 of safety margin for the demonstrated intensities to date. For a further increase in the intensity for RHIC and eRHIC we evaluate upgrade options for the beam abort system. |
||
DOI • | reference for this paper ※ https://doi.org/10.18429/JACoW-NAPAC2019-TUPLO03 | |
About • | paper received ※ 26 August 2019 paper accepted ※ 05 September 2019 issue date ※ 08 October 2019 | |
Export • | reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml) | |
TUPLO04 | The Latest Code Development Progress of JSPEC | 539 |
|
||
Funding: This material is based upon work supported by the U.S. Department of Energy, Office of Science, Office of Nuclear Physics under contract DE-AC05-06OR23177. The JLab Simulation Package on Electron Cooling (JSPEC) is an open source software developed at Jefferson Lab for electron cooling and intrabeam scattering (IBS) simulations. IBS is an important factor that leads to the growth of the beam emittance and hence the reduction of the luminosity in a high density ion collider ring. Electron cooling is an effective measure to overcome the IBS effect. Although JSPEC is initiated to fulfill the simulation needs in JLab Electron Ion Collider project, it can be used as a general design tool for other accelerators. JSPEC provides various models of the ion beam and the electron beam and it calculates the expansion rate and simulates the evolution of the ion beam under the IBS and/or electron cooling effect. In this report, we will give a brief introduction of JSPEC and then present the latest code development progress of JSPEC, including new models, algorithms, and the user interface. |
||
DOI • | reference for this paper ※ https://doi.org/10.18429/JACoW-NAPAC2019-TUPLO04 | |
About • | paper received ※ 20 September 2019 paper accepted ※ 19 November 2019 issue date ※ 08 October 2019 | |
Export • | reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml) | |
TUPLO05 | Fixed Target Operation at RHIC in 2019 | 542 |
|
||
Funding: Work supported by Brookhaven Science Associates, LLC under Contract No. DE-AC02-98CH10886 with the U.S. Department of Energy. RHIC operated in fixed target mode at beam energies 4.59, 7.3, and 31.2 GeV/nucleon in 2019 as a part of the Beam Energy Scan II program. To scrape beam halo effectively at the fixed target which is 2.05 m away from the center of the STAR detectors, lattice design with relative large beta function at STAR was implemented at the two lower energies. The kickers of the base-band tune (BBQ) measurement system were engaged to dilute the beam transversely to maintain the event rate except for 31.2 GeV/nucleon. In addition, beam orbit control, tune and chromaticity adjustments were used to level the event rate. This paper will review the operational experience of RHIC in fixed target mode at various energies. |
||
DOI • | reference for this paper ※ https://doi.org/10.18429/JACoW-NAPAC2019-TUPLO05 | |
About • | paper received ※ 21 August 2019 paper accepted ※ 15 September 2019 issue date ※ 08 October 2019 | |
Export • | reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml) | |
TUPLO06 | Weak-Strong Beam-Beam Simulation for eRHIC | 545 |
|
||
Funding: Work supported by Brookhaven Science Associates, LLC under Contract No. DE-AC02-98CH10886 with the U.S. Department of Energy. In the eRHIC, to compensate the geometric luminosity loss due to the crossing angle, crab cavities are to be installed on both sides of the interaction point. When the proton bunch length is comparable to the wavelength of its crab cavities, protons will not be perfectly tilted in the x-z plane. In the article, we employ weak-strong beam-beam interaction model to calculate the proton beam size growth rates and luminosity degradation rate with various machine and time parameters. The goal of these studies is to optimize the the beam-beam related machine and beam parameters of eRHIC. |
||
DOI • | reference for this paper ※ https://doi.org/10.18429/JACoW-NAPAC2019-TUPLO06 | |
About • | paper received ※ 29 August 2019 paper accepted ※ 03 September 2019 issue date ※ 08 October 2019 | |
Export • | reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml) | |
TUPLO07 | Calculation of Action Diffusion With Crabbed Collision in eRHIC | 549 |
|
||
Funding: Work supported by Brookhaven Science Associates, LLC under Contract No. DE-AC02-98CH10886 with the U.S. Department of Energy. In the eRHIC, to compensate the geometric luminosity loss due to the crossing angle, crab cavities are to be installed on both sides of the interaction point. When the proton bunch length is comparable to the wavelength of its crab cavities, protons will not be perfectly tilted in the x-z plane. In the article, we develop a simulation code to calculate the transverse action diffusion rate as function of the initial proton longitudinal action. The goal of this study is to identify the contributions from various protons to the overall emittance growth. Tune scan is also performed to locate optimum working points which yield less proton emittance growth. |
||
DOI • | reference for this paper ※ https://doi.org/10.18429/JACoW-NAPAC2019-TUPLO07 | |
About • | paper received ※ 29 August 2019 paper accepted ※ 03 September 2019 issue date ※ 08 October 2019 | |
Export • | reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml) | |
TUPLO09 | Electron-Ion Collider Performance Studies With Beam Synchronization via Gear-Change | 553 |
SUPLH13 | use link to see paper's listing under its alternate paper code | |
|
||
Beam synchronization of the future electron-ion collider (EIC) is studied with introducing different bunch numbers in the two colliding beams. This allows non-pairwise collisions between the bunches of the two beams and is known as "gear-change", whereby one bunch of the first beam collides with all other bunches of the second beam, one at a time. Here we report on the study of how the beam dynamics of the Jefferson Lab Electron Ion collider concept is affected by the gear change. For this study, we use the new GPU-based code (GHOST). It features symplectic one-turn maps for particle tracking and Bassetti-Erskine approach for beam-beam interactions. | ||
DOI • | reference for this paper ※ https://doi.org/10.18429/JACoW-NAPAC2019-TUPLO09 | |
About • | paper received ※ 28 August 2019 paper accepted ※ 05 September 2019 issue date ※ 08 October 2019 | |
Export • | reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml) | |
TUPLO11 |
eRHIC Design Update | |
MOYBA4 | use link to access more material from this paper's primary paper code | |
|
||
Funding: Work supported by Brookhaven Science Associates, LLC under Contract No. DE-AC02-98CH10886 with the U.S. Department of Energy. The future electron-ion collider (EIC) aims at an electron-proton luminosity of 1033 to 1034 cm-2 sec-1 and a center-of-mass energy range from 20 to 140 GeV. The eRHIC design has been continuously evolving over a couple of years and has reached a considerable level of maturity. The concept is generally conservative with very few risk items which are mitigated in various ways. |
||
![]() |
Slides MOYBA4 [5.466 MB] | |
DOI • | reference for this paper ※ https://doi.org/10.18429/JACoW-NAPAC2019-MOYBA4 | |
About • | paper received ※ 24 August 2019 paper accepted ※ 31 August 2019 issue date ※ 08 October 2019 | |
Export • | reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml) | |
TUPLO12 | Off-Momentum Optics Correction in RHIC | 556 |
|
||
Funding: Work supported by Brookhaven Science Associates, LLC under Contract No. DE-AC02-98CH10886 with the U.S. Department of Energy. Future operations of the electron-ion collider eRHIC call for beams circulating off of the magnetic center of all arc elements. In order to ensure that both stable beam conditions and the desired circumference change can be achieved, dedicated experiments were conducted during RHIC Run18, which included the first off-momentum linear optics correction. This article reviews the experimental setup as well as the dedicated algorithm for optics correction, and presents the measured radial excursion and residual off-momentum beta-beat. |
||
DOI • | reference for this paper ※ https://doi.org/10.18429/JACoW-NAPAC2019-TUPLO12 | |
About • | paper received ※ 27 August 2019 paper accepted ※ 15 September 2019 issue date ※ 08 October 2019 | |
Export • | reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml) | |
TUPLO13 |
Interaction Region Magnets for Future Electron-Ion Collider at Jefferson Lab | |
TUZBA4 | use link to access more material from this paper's primary paper code | |
|
||
The Jefferson Lab Electron Ion Collider (JLEIC) is a proposed new machine for nuclear physics research. It uses the existing CEBAF accelerator as a full energy injector to deliver 3 to 12 GeV electrons into a new electron collider ring. An all new ion accelerator and collider complex will deliver up to 200 GeV protons. The machine has luminosity goals of 1034 cm-2 ses−1. The whole detector region including forward detection covers about 80 meters of the JLEIC complex. The interaction region design has recently been optimized to accommodate 200 GeV proton energy using conventional NbTi superconducting magnet technology. This paper will describe the requirements and preliminary designs for both the ion and electron beam magnets in the most complex 32 m long interaction region (IR) around the interaction point (IP). The interaction region has over thirty-seven superconducting magnets operating at 4.5K; these include dipoles, quadrupoles, skew-quadrupoles, solenoids, horizontal and vertical correctors and higher order multipole magnets. The paper will also discuss the electromagnetic interaction between these magnets. | ||
![]() |
Slides TUZBA4 [6.444 MB] | |
![]() |
Poster TUZBA4 [1.549 MB] | |
DOI • | reference for this paper ※ https://doi.org/10.18429/JACoW-NAPAC2019-TUZBA4 | |
About • | paper received ※ 27 August 2019 paper accepted ※ 31 August 2019 issue date ※ 08 October 2019 | |
Export • | reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml) | |
TUPLO14 |
Computation of Magnetized Dynamic Friction Force Based on a Reduced Binary Interaction Model | |
TUZBA6 | use link to access more material from this paper's primary paper code | |
|
||
Funding: This work is supported by the U.S. DOE Office of Science, Office of Nuclear Physics, under Award Number DE-SC0015212. Relativistic magnetized electron cooling is an essential technique for achieving the ion beam luminosity requirements of proposed electron-ion collider facilities. Because the cooling system will have to operate in previously untested parameter regimes, accurate computation of magnetized dynamic friction is required at the design stage. In particular, one has to include all relevant physics that might increase the cooling time, such as short interaction time in the cooler, space charge forces, field errors and complicated phase space distributions of imperfectly magnetized electron beams. We will present recent work on a new semi-analytic treatment of momentum transfer from an ion to a distribution of magnetized electrons, and discuss its application to calculation of dynamic friction in the parameter regime relevant to the JLEIC and eRHIC cooling system design. |
||
![]() |
Slides TUZBA6 [2.751 MB] | |
Export • | reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml) | |
TUPLO15 | Multipole Effects on Dynamic Aperture in JLEIC Ion Collider Ring | 559 |
|
||
Funding: This material is based upon work supported by the U.S. DoE under Contracts No. DE-AC05-06OR23177, DE-AC02-76SF00515, and DEAC03-76SF00098. In a collider, stronger focusing at the interaction point (IP) for low beta-star and high luminosity produces large beams at final focusing quadrupoles (FFQs). To achieve the high luminosity requirement in the Jefferson Lab Electron-Ion Collider (JLEIC), the interaction region (IR) beta functions peak at 4.2 km in downstream FFQs. These large beta functions and FFQ multipoles reduce the dynamic aperture (DA) of the ring. A study of the multipole effects on the DA was performed to determine limits on multipoles, and to include a multipole compensation scheme to increase the DA and beam lifetime. |
||
DOI • | reference for this paper ※ https://doi.org/10.18429/JACoW-NAPAC2019-TUPLO15 | |
About • | paper received ※ 28 August 2019 paper accepted ※ 04 September 2019 issue date ※ 08 October 2019 | |
Export • | reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml) | |