NAPAC2019 - List of Authors (Fedotov, A.V.)

Paper	Title	Page
MOOHC2	The US Electron Ion Collider Accelerator Designs	1
	A. Seryi, S.V. Benson, S.A. Bogacz, P.D. Brindza, M.W. Bruker, A. Camsonne, E. Daly, P. Degtiarenko, Y.S. Derbenev, M. Diefenthaler, J. Dolbeck, R. Ent, R. Fair, D. Fazenbaker, Y. Furletova, B.R. Gamage, D. Gaskell, R.L. Geng, P. Ghoshal, J.M. Grames, J. Guo, F.E. Hannon, L. Harwood, S. Henderson, H. Huang, A. Hutton, K. Jordan, D.H. Kashy, A.J. Kimber, G.A. Krafft, R. Lassiter, R. Li, F. Lin, M.A. Mamun, F. Marhauser, R. McKeown, T.J. Michalski, V.S. Morozov, P. Nadel-Turonski, E.A. Nissen, G.-T. Park, H. Park, M. Poelker, T. Powers, R. Rajput-Ghoshal, R.A. Rimmer, Y. Roblin, D. Romanov, P. Rossi, T. Satogata, M.F. Spata, R. Suleiman, A.V. Sy, C. Tennant, H. Wang, S. Wang, C. Weiss, M. Wiseman, W. Wittmer, R. Yoshida, H. Zhang, S. Zhang, Y. Zhang, Z.W. Zhao JLab, Newport News, Virginia, USA D.T. Abell, D.L. Bruhwiler, I.V. Pogorelov RadiaSoft LLC, Boulder, Colorado, USA E.C. Aschenauer, G. Bassi, J. Beebe-Wang, J.S. Berg, M. Blaskiewicz, A. Blednykh, J.M. Brennan, S.J. Brooks, K.A. Brown, K.A. Drees, A.V. Fedotov, W. Fischer, D.M. Gassner, W. Guo, Y. Hao, A. Hershcovitch, H. Huang, W.A. Jackson, J. Kewisch, A. Kiselev, V. Litvinenko, C. Liu, H. Lovelace III, Y. Luo, F. Méot, M.G. Minty, C. Montag, R.B. Palmer, B. Parker, S. Peggs, V. Ptitsyn, V.H. Ranjbar, G. Robert-Demolaize, T. Roser, S. Seletskiy, V.V. Smaluk, K.S. Smith, S. Tepikian, P. Thieberger, D. Trbojevic, N. Tsoupas, E. Wang, W.-T. Weng, F.J. Willeke, H. Witte, Q. Wu, W. Xu, A. Zaltsman, W. Zhang BNL, Upton, New York, USA D.P. Barber DESY, Hamburg, Germany I.V. Bazarov Cornell University, Ithaca, New York, USA G.I. Bell, J.R. Cary Tech-X, Boulder, Colorado, USA Y. Cai, Y.M. Nosochkov, A. Novokhatski, G. Stupakov, M.K. Sullivan, C.-Y. Tsai SLAC, Menlo Park, California, USA Z.A. Conway, M.P. Kelly, B. Mustapha, U. Wienands, A. Zholents ANL, Lemont, Illinois, USA S.U. De Silva, J.R. Delayen, H. Huang, C. Hyde, S. Sosa, B. Terzić ODU, Norfolk, Virginia, USA K.E. Deitrick, G.H. Hoffstaetter Cornell University (CLASSE), Cornell Laboratory for Accelerator-Based Sciences and Education, Ithaca, New York, USA D. Douglas Douglas Consulting, York, Virginia, USA V.G. Dudnikov, R.P. Johnson Muons, Inc, Illinois, USA B. Erdelyi, P. Piot Northern Illinois University, DeKalb, Illinois, USA J.D. Fox Stanford University, Stanford, California, USA J. Gerity, T.L. Mann, P.M. McIntyre, N. Pogue, A. Sattarov Texas A&M University, College Station, USA E. Gianfelice-Wendt, S. Nagaitsev Fermilab, Batavia, Illinois, USA Y. Hao, P.N. Ostroumov, A.S. Plastun, R.C. York FRIB, East Lansing, Michigan, USA T. Mastoridis CalPoly, San Luis Obispo, California, USA J.D. Maxwell, R. Milner, M. Musgrave MIT, Cambridge, Massachusetts, USA J. Qiang, G.L. Sabbi LBNL, Berkeley, California, USA D. Teytelman Dimtel, Redwood City, California, USA R.C. York NSCL, East Lansing, Michigan, USA
	With the completion of the National Academies of Sciences Assessment of a US Electron-Ion Collider, the prospects for construction of such a facility have taken a step forward. This paper provides an overview of the two site-specific EIC designs: JLEIC (Jefferson Lab) and eRHIC (BNL) as well as brief overview of ongoing EIC R&D.
	Slides MOOHC2 [14.774 MB]
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-NAPAC2019-MOOHC2
About •	paper received ※ 29 August 2019 paper accepted ※ 04 September 2019 issue date ※ 08 October 2019
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MOYBA4	eRHIC Design Update	18
TUPLO11	use link to see paper's listing under its alternate paper code
	C. Montag, G. Bassi, J. Beebe-Wang, J.S. Berg, M. Blaskiewicz, A. Blednykh, J.M. Brennan, S.J. Brooks, K.A. Brown, K.A. Drees, A.V. Fedotov, W. Fischer, D.M. Gassner, Y. Hao, A. Hershcovitch, C. Hetzel, D. Holmes, H. Huang, W.A. Jackson, J. Kewisch, Y. Li, C. Liu, H. Lovelace III, Y. Luo, F. Méot, M.G. Minty, R.B. Palmer, B. Parker, S. Peggs, V. Ptitsyn, V.H. Ranjbar, G. Robert-Demolaize, S. Seletskiy, V.V. Smaluk, K.S. Smith, S. Tepikian, P. Thieberger, D. Trbojevic, N. Tsoupas, S. Verdú-Andrés, W.-T. Weng, F.J. Willeke, H. Witte, Q. Wu, W. Xu, A. Zaltsman, W. Zhang BNL, Upton, New York, USA Y. Cai, Y.M. Nosochkov SLAC, Menlo Park, California, USA E. Gianfelice-Wendt Fermilab, Batavia, Illinois, USA
	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
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MOYBA6	Accelerator Performance During the Beam Energy Scan II at RHIC in 2019	26
	C. Liu, I. Blacker, M. Blaskiewicz, K.A. Brown, D. Bruno, K.A. Drees, A.V. Fedotov, W. Fischer, C.J. Gardner, C.E. Giorgio, X. Gu, T. Hayes, H. Huang, R.L. Hulsart, D. Kayran, N.A. Kling, Y. Luo, D. Maffei, G.J. Marr, B. Martin, A. Marusic, K. Mernick, R.J. Michnoff, M.G. Minty, C. Montag, J. Morris, C. Naylor, S. Nemesure, I. Pinayev, S. Polizzo, V.H. Ranjbar, D. Raparia, G. Robert-Demolaize, T. Roser, J. Sandberg, V. Schoefer, F. Severino, T.C. Shrey, K.S. Smith, S. Tepikian, P. Thieberger, A. Zaltsman, K. Zeno, I.Y. Zhang, W. Zhang BNL, Upton, New York, USA
	Funding: Work supported by Brookhaven Science Associates, LLC under Contract No. DE-AC02-98CH10886 with the U.S. Department of Energy. RHIC provided Au-Au collisions at beam energies of 9.8, 7.3, 4.59 and 3.85 GeV/nucleon during the first year of the Beam Energy Scan II in 2019. The physics goals at the first two higher beam energies were achieved. At the two lower beam energies, bunched electron beam cooling has been demonstrated successfully. The accelerator performance was improved compared to when RHIC was operated at these energies in earlier years. This article will introduce the challenges to operate RHIC at low energies and the corresponding countermeasures, and review the improvement of accelerator performance during the operation in 2019.
	Slides MOYBA6 [6.579 MB]
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-NAPAC2019-MOYBA6
About •	paper received ※ 21 August 2019 paper accepted ※ 06 September 2019 issue date ※ 08 October 2019
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MOPLM18	Design of the 2-Stage Laser Transport for the Low Energy RHIC Electron Cooling (LEReC) DC Photogun	144
	P. Inacker, S. Bellavia, A.J. Curcio, A.V. Fedotov, W. Fischer, D.M. Gassner, J.P. Jamilkowski, P.K. Kankiya, D. Kayran, D. Lehn, R. Meier, T.A. Miller, M.G. Minty, S.K. Nayak, L.K. Nguyen, L. Smart, C.J. Spataro, A. Sukhanov, J.E. Tuozzolo, Z. Zhao BNL, Upton, New York, USA
	Funding: Work supported by Brookhaven Science Associates, LLC under Contract No. DE-AC02-98CH10886 with the U.S. Department of Energy. The electron beam for the recently constructed Low Energy RHIC electron Cooler (LEReC) at Brookhaven National Laboratory is generated by a high-power fiber laser illuminating a photocathode. The pointing stability of the low-energy electron beam, which is crucial to maintain within acceptable limits given the long beam transport, is highly dependent on the center-of-mass (CoM) stability of the laser spot on the photocathode. For reasons of accessibility during operations, the laser itself is located outside the accelerator tunnel, leading to the need to propagate the laser beam 34 m via three laser tables to the photocathode. The challenges to achieving the required CoM stability of 10 microns on the photocathode thus requires mitigation of vibrations along the transport and of weather- and season-related environmental effects, while preserving accessibility and diagnostic capabilities with proactive design. After successful commissioning of the full transport in 2018/19, we report on our solutions to these design challenges. LEReC Photocathode DC Gun Beam Test Results - D. Kayran Conference: C18-04-29, p.TUPMF025 Commissioning of Electron Accelerator LEReC for Bunch Beam Cooling - D.Kayran, NAPAC19
	Poster MOPLM18 [1.970 MB]
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-NAPAC2019-MOPLM18
About •	paper received ※ 27 August 2019 paper accepted ※ 31 August 2019 issue date ※ 08 October 2019
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TUZBA1	Commissioning of the Electron Accelerator LEReC for Bunched Beam Cooling	330
	D. Kayran, Z. Altinbas, D. Bruno, M.R. Costanzo, K.A. Drees, A.V. Fedotov, W. Fischer, M. Gaowei, D.M. Gassner, X. Gu, R.L. Hulsart, P. Inacker, J.P. Jamilkowski, Y.C. Jing, J. Kewisch, C.J. Liaw, C. Liu, J. Ma, K. Mernick, T.A. Miller, M.G. Minty, L.K. Nguyen, M.C. Paniccia, I. Pinayev, V. Ptitsyn, V. Schoefer, S. Seletskiy, F. Severino, T.C. Shrey, L. Smart, K.S. Smith, A. Sukhanov, P. Thieberger, J.E. Tuozzolo, E. Wang, G. Wang, W. Xu, A. Zaltsman, H. Zhao, Z. Zhao BNL, Upton, New York, USA
	Funding: Work supported by Brookhaven Science Associates, LLC under Contract No. DE-AC02-98CH10886 with the U.S. Department of Energy. The brand-new state of the art electron accelerator, LEReC, was built and commissioned at BNL. LEReC accelerator includes a photocathode DC gun, a laser system, a photocathode delivery system, magnets, beam diagnostics, a SRF booster cavity, and a set of Normal Conducting RF cavities to provide sufficient flexibility to tune the beam in the longitudinal phase space. Electron beam quality suitable for cooling in the Relativistic Heavy Ion Collider (RHIC) was achieved [1], which lead to the first demonstration of bunched beam electron cooling of hadron beams [2]. This presentation will discuss commissioning results, achieved beam parameters and performance of the LEReC systems. [1] D.Kayran et al., First results from Commissioning of LEReC, in Proc of IPAC2019 [2] A.Fedotov et al., First electron cooling of hadron beams using a bunched electron beam, presented at NAPAC2019
	Slides TUZBA1 [18.343 MB]
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-NAPAC2019-TUZBA1
About •	paper received ※ 27 August 2019 paper accepted ※ 31 August 2019 issue date ※ 08 October 2019
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TUZBB3	Precise Beam Velocity Matching for the Experimental Demonstration of Ion Cooling With a Bunched Electron Beam	356
	S. Seletskiy, M. Blaskiewicz, K.A. Drees, A.V. Fedotov, W. Fischer, D.M. Gassner, R.L. Hulsart, D. Kayran, J. Kewisch, K. Mernick, R.J. Michnoff, T.A. Miller, G. Robert-Demolaize, V. Schoefer, H. Song, P. Thieberger, P. Wanderer BNL, Upton, New York, USA
	The first ever electron cooling based on the RF acceleration of electron bunches was experimentally demonstrated on April 5, 2019 at the Low Energy RHIC Electron Cooler (LEReC) at BNL. The critical step in obtaining successful cooling of the Au ion bunches in the RHIC cooling sections was the accurate matching of average longitudinal velocities of electron and ion beams corresponding to a relative error of less than 5·10^-4 in the e-beam momentum. Since the electron beam kinetic energy is just 1.6 MeV, measuring the absolute e-beam energy with sufficient accuracy and eventually achieving the electron-ion velocity matching was a nontrivial task. In this paper we describe our experience with measuring and setting the e-beam energy at LEReC.
	Slides TUZBB3 [1.340 MB]
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-NAPAC2019-TUZBB3
About •	paper received ※ 26 August 2019 paper accepted ※ 31 August 2019 issue date ※ 08 October 2019
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TUPLO05	Fixed Target Operation at RHIC in 2019	542
	C. Liu, I. Blacker, M. Blaskiewicz, K.A. Brown, D. Bruno, K.A. Drees, A.V. Fedotov, W. Fischer, C.J. Gardner, C.E. Giorgio, X. Gu, T. Hayes, H. Huang, R.L. Hulsart, D. Kayran, N.A. Kling, Y. Luo, D. Maffei, G.J. Marr, B. Martin, A. Marusic, K. Mernick, R.J. Michnoff, M.G. Minty, C. Montag, J. Morris, C. Naylor, S. Nemesure, I. Pinayev, S. Polizzo, V.H. Ranjbar, D. Raparia, G. Robert-Demolaize, T. Roser, J. Sandberg, V. Schoefer, F. Severino, T.C. Shrey, K.S. Smith, S. Tepikian, P. Thieberger, A. Zaltsman, K. Zeno, I.Y. Zhang, W. Zhang BNL, Upton, New York, USA
	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
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THYBA6	Active Pointing Stabilization Techniques Applied to the Low Energy RHIC Electron Cooling Laser Transport at BNL	938
MOPLM22	use link to see paper's listing under its alternate paper code
SUPLH07	use link to see paper's listing under its alternate paper code
	L.K. Nguyen, A.J. Curcio, W.J. Eisele, A.V. Fedotov, A. Fernando, W. Fischer, P. Inacker, J.P. Jamilkowski, D. Kayran, K. Kulmatycski, D. Lehn, T.A. Miller, M.G. Minty, A. Sukhanov BNL, Upton, New York, USA
	Funding: Work supported by Brookhaven Science Associates, LLC under Contract No. DE-AC02-98CH10886 with the U.S. Department of Energy. The electron beam for the Low Energy RHIC electron Cooler (LEReC) at Brookhaven National Laboratory (BNL) is generated by a high-power fiber laser illuminating a photocathode. The pointing stability of the electron beam, which is crucial given its long transport, is highly dependent on the center-of-mass (CoM) stability of the laser spot on the photocathode. For reasons of accessibility during operations, the laser is located outside the accelerator tunnel, and the laser beam is propagated over a total distance of 34 m via three laser tables to the photocathode. The challenges to achieving the required CoM stability of 10 microns RMS on the photocathode include mitigation of the effects of vibrations along the transport and of weather- and season-related environmental effects, while preserving accessibility and diagnostic capabilities. Due to the insufficiency of infrastructure alone in overcoming these challenges, two active laser transport stabilization systems aimed at addressing specific types of position instability were installed during the 2018 Shutdown. After successful commissioning of the full transport in 2018/19, we report on our solutions to these design challenges.
	Slides THYBA6 [3.426 MB]
	Poster THYBA6 [1.299 MB]
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-NAPAC2019-THYBA6
About •	paper received ※ 27 August 2019 paper accepted ※ 31 August 2019 issue date ※ 08 October 2019
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THZBA5	First Electron Cooling of Hadron Beams Using a Bunched Electron Beam	957
	A.V. Fedotov, Z. Altinbas, M. Blaskiewicz, J.M. Brennan, D. Bruno, J.C. Brutus, M.R. Costanzo, K.A. Drees, W. Fischer, J.M. Fite, M. Gaowei, D.M. Gassner, X. Gu, J. Halinski, K. Hamdi, L.R. Hammons, T. Hayes, R.L. Hulsart, P. Inacker, J.P. Jamilkowski, Y.C. Jing, P.K. Kankiya, D. Kayran, J. Kewisch, D. Lehn, C.J. Liaw, C. Liu, J. Ma, G.J. Mahler, M. Mapes, A. Marusic, K. Mernick, C. Mi, R.J. Michnoff, T.A. Miller, M.G. Minty, S.K. Nayak, L.K. Nguyen, M.C. Paniccia, I. Pinayev, S. Polizzo, V. Ptitsyn, T. Rao, G. Robert-Demolaize, T. Roser, J. Sandberg, V. Schoefer, S. Seletskiy, F. Severino, T.C. Shrey, L. Smart, K.S. Smith, H. Song, A. Sukhanov, R. Than, P. Thieberger, S.M. Trabocchi, J.E. Tuozzolo, P. Wanderer, E. Wang, G. Wang, D. Weiss, B.P. Xiao, T. Xin, W. Xu, A. Zaltsman, H. Zhao, Z. Zhao BNL, Upton, New York, USA
	Funding: Work supported by the U.S. Department of Energy. The Low Energy RHIC electron Cooler (LEReC) was recently constructed and commissioned at BNL. The LEReC is the first electron cooler based on the RF acceleration of electron bunches (previous electron coolers all used DC beams). Bunched electron beams are necessary for cooling hadron beams at high energies. The challenges of such an approach include generation of electron beams suitable for cooling, delivery of electron beams of the required quality to the cooling sections without degradation of beam emittances and energy spread, achieving required small angles between electrons and ions in the cooling sections, precise energy matching between the two beams, high-current operation of the electron accelerator, as well as several physics effects related to bunched beam cooling. Following successful commissioning of the electron accelerator in 2018, the focus of the LEReC project in 2019 was on establishing electron-ion interactions and demonstration of cooling process using electron energy of 1.6MeV (ion energy of 3.85GeV/n), which is the lowest energy of interest. Here we report on the first demonstration of Au ion cooling in RHIC using this new approach.
	Slides THZBA5 [16.417 MB]
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-NAPAC2019-THZBA5
About •	paper received ※ 16 August 2019 paper accepted ※ 31 August 2019 issue date ※ 08 October 2019
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Paper

Title

Page

The US Electron Ion Collider Accelerator Designs

1

A. Seryi, S.V. Benson, S.A. Bogacz, P.D. Brindza, M.W. Bruker, A. Camsonne, E. Daly, P. Degtiarenko, Y.S. Derbenev, M. Diefenthaler, J. Dolbeck, R. Ent, R. Fair, D. Fazenbaker, Y. Furletova, B.R. Gamage, D. Gaskell, R.L. Geng, P. Ghoshal, J.M. Grames, J. Guo, F.E. Hannon, L. Harwood, S. Henderson, H. Huang, A. Hutton, K. Jordan, D.H. Kashy, A.J. Kimber, G.A. Krafft, R. Lassiter, R. Li, F. Lin, M.A. Mamun, F. Marhauser, R. McKeown, T.J. Michalski, V.S. Morozov, P. Nadel-Turonski, E.A. Nissen, G.-T. Park, H. Park, M. Poelker, T. Powers, R. Rajput-Ghoshal, R.A. Rimmer, Y. Roblin, D. Romanov, P. Rossi, T. Satogata, M.F. Spata, R. Suleiman, A.V. Sy, C. Tennant, H. Wang, S. Wang, C. Weiss, M. Wiseman, W. Wittmer, R. Yoshida, H. Zhang, S. Zhang, Y. Zhang, Z.W. Zhao
JLab, Newport News, Virginia, USA
D.T. Abell, D.L. Bruhwiler, I.V. Pogorelov
RadiaSoft LLC, Boulder, Colorado, USA
E.C. Aschenauer, G. Bassi, J. Beebe-Wang, J.S. Berg, M. Blaskiewicz, A. Blednykh, J.M. Brennan, S.J. Brooks, K.A. Brown, K.A. Drees, A.V. Fedotov, W. Fischer, D.M. Gassner, W. Guo, Y. Hao, A. Hershcovitch, H. Huang, W.A. Jackson, J. Kewisch, A. Kiselev, V. Litvinenko, C. Liu, H. Lovelace III, Y. Luo, F. Méot, M.G. Minty, C. Montag, R.B. Palmer, B. Parker, S. Peggs, V. Ptitsyn, V.H. Ranjbar, G. Robert-Demolaize, T. Roser, S. Seletskiy, V.V. Smaluk, K.S. Smith, S. Tepikian, P. Thieberger, D. Trbojevic, N. Tsoupas, E. Wang, W.-T. Weng, F.J. Willeke, H. Witte, Q. Wu, W. Xu, A. Zaltsman, W. Zhang
BNL, Upton, New York, USA
D.P. Barber
DESY, Hamburg, Germany
I.V. Bazarov
Cornell University, Ithaca, New York, USA
G.I. Bell, J.R. Cary
Tech-X, Boulder, Colorado, USA
Y. Cai, Y.M. Nosochkov, A. Novokhatski, G. Stupakov, M.K. Sullivan, C.-Y. Tsai
SLAC, Menlo Park, California, USA
Z.A. Conway, M.P. Kelly, B. Mustapha, U. Wienands, A. Zholents
ANL, Lemont, Illinois, USA
S.U. De Silva, J.R. Delayen, H. Huang, C. Hyde, S. Sosa, B. Terzić
ODU, Norfolk, Virginia, USA
K.E. Deitrick, G.H. Hoffstaetter
Cornell University (CLASSE), Cornell Laboratory for Accelerator-Based Sciences and Education, Ithaca, New York, USA
D. Douglas
Douglas Consulting, York, Virginia, USA
V.G. Dudnikov, R.P. Johnson
Muons, Inc, Illinois, USA
B. Erdelyi, P. Piot
Northern Illinois University, DeKalb, Illinois, USA
J.D. Fox
Stanford University, Stanford, California, USA
J. Gerity, T.L. Mann, P.M. McIntyre, N. Pogue, A. Sattarov
Texas A&M University, College Station, USA
E. Gianfelice-Wendt, S. Nagaitsev
Fermilab, Batavia, Illinois, USA
Y. Hao, P.N. Ostroumov, A.S. Plastun, R.C. York
FRIB, East Lansing, Michigan, USA
T. Mastoridis
CalPoly, San Luis Obispo, California, USA
J.D. Maxwell, R. Milner, M. Musgrave
MIT, Cambridge, Massachusetts, USA
J. Qiang, G.L. Sabbi
LBNL, Berkeley, California, USA
D. Teytelman
Dimtel, Redwood City, California, USA
R.C. York
NSCL, East Lansing, Michigan, USA

With the completion of the National Academies of Sciences Assessment of a US Electron-Ion Collider, the prospects for construction of such a facility have taken a step forward. This paper provides an overview of the two site-specific EIC designs: JLEIC (Jefferson Lab) and eRHIC (BNL) as well as brief overview of ongoing EIC R&D.

Slides MOOHC2 [14.774 MB]

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-NAPAC2019-MOOHC2

About •

paper received ※ 29 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)

MOYBA4

eRHIC Design Update

18

TUPLO11

use link to see paper's listing under its alternate paper code

C. Montag, G. Bassi, J. Beebe-Wang, J.S. Berg, M. Blaskiewicz, A. Blednykh, J.M. Brennan, S.J. Brooks, K.A. Brown, K.A. Drees, A.V. Fedotov, W. Fischer, D.M. Gassner, Y. Hao, A. Hershcovitch, C. Hetzel, D. Holmes, H. Huang, W.A. Jackson, J. Kewisch, Y. Li, C. Liu, H. Lovelace III, Y. Luo, F. Méot, M.G. Minty, R.B. Palmer, B. Parker, S. Peggs, V. Ptitsyn, V.H. Ranjbar, G. Robert-Demolaize, S. Seletskiy, V.V. Smaluk, K.S. Smith, S. Tepikian, P. Thieberger, D. Trbojevic, N. Tsoupas, S. Verdú-Andrés, W.-T. Weng, F.J. Willeke, H. Witte, Q. Wu, W. Xu, A. Zaltsman, W. Zhang
BNL, Upton, New York, USA
Y. Cai, Y.M. Nosochkov
SLAC, Menlo Park, California, USA
E. Gianfelice-Wendt
Fermilab, Batavia, Illinois, USA

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]

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reference for this paper ※ https://doi.org/10.18429/JACoW-NAPAC2019-MOYBA4

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paper received ※ 24 August 2019 paper accepted ※ 31 August 2019 issue date ※ 08 October 2019

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MOYBA6

Accelerator Performance During the Beam Energy Scan II at RHIC in 2019

26

C. Liu, I. Blacker, M. Blaskiewicz, K.A. Brown, D. Bruno, K.A. Drees, A.V. Fedotov, W. Fischer, C.J. Gardner, C.E. Giorgio, X. Gu, T. Hayes, H. Huang, R.L. Hulsart, D. Kayran, N.A. Kling, Y. Luo, D. Maffei, G.J. Marr, B. Martin, A. Marusic, K. Mernick, R.J. Michnoff, M.G. Minty, C. Montag, J. Morris, C. Naylor, S. Nemesure, I. Pinayev, S. Polizzo, V.H. Ranjbar, D. Raparia, G. Robert-Demolaize, T. Roser, J. Sandberg, V. Schoefer, F. Severino, T.C. Shrey, K.S. Smith, S. Tepikian, P. Thieberger, A. Zaltsman, K. Zeno, I.Y. Zhang, W. Zhang
BNL, Upton, New York, USA

Funding: Work supported by Brookhaven Science Associates, LLC under Contract No. DE-AC02-98CH10886 with the U.S. Department of Energy.
RHIC provided Au-Au collisions at beam energies of 9.8, 7.3, 4.59 and 3.85 GeV/nucleon during the first year of the Beam Energy Scan II in 2019. The physics goals at the first two higher beam energies were achieved. At the two lower beam energies, bunched electron beam cooling has been demonstrated successfully. The accelerator performance was improved compared to when RHIC was operated at these energies in earlier years. This article will introduce the challenges to operate RHIC at low energies and the corresponding countermeasures, and review the improvement of accelerator performance during the operation in 2019.

Slides MOYBA6 [6.579 MB]

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reference for this paper ※ https://doi.org/10.18429/JACoW-NAPAC2019-MOYBA6

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paper received ※ 21 August 2019 paper accepted ※ 06 September 2019 issue date ※ 08 October 2019

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MOPLM18

Design of the 2-Stage Laser Transport for the Low Energy RHIC Electron Cooling (LEReC) DC Photogun

144

P. Inacker, S. Bellavia, A.J. Curcio, A.V. Fedotov, W. Fischer, D.M. Gassner, J.P. Jamilkowski, P.K. Kankiya, D. Kayran, D. Lehn, R. Meier, T.A. Miller, M.G. Minty, S.K. Nayak, L.K. Nguyen, L. Smart, C.J. Spataro, A. Sukhanov, J.E. Tuozzolo, Z. Zhao
BNL, Upton, New York, USA

Funding: Work supported by Brookhaven Science Associates, LLC under Contract No. DE-AC02-98CH10886 with the U.S. Department of Energy.
The electron beam for the recently constructed Low Energy RHIC electron Cooler (LEReC) at Brookhaven National Laboratory is generated by a high-power fiber laser illuminating a photocathode. The pointing stability of the low-energy electron beam, which is crucial to maintain within acceptable limits given the long beam transport, is highly dependent on the center-of-mass (CoM) stability of the laser spot on the photocathode. For reasons of accessibility during operations, the laser itself is located outside the accelerator tunnel, leading to the need to propagate the laser beam 34 m via three laser tables to the photocathode. The challenges to achieving the required CoM stability of 10 microns on the photocathode thus requires mitigation of vibrations along the transport and of weather- and season-related environmental effects, while preserving accessibility and diagnostic capabilities with proactive design. After successful commissioning of the full transport in 2018/19, we report on our solutions to these design challenges.
LEReC Photocathode DC Gun Beam Test Results - D. Kayran Conference: C18-04-29, p.TUPMF025
Commissioning of Electron Accelerator LEReC for Bunch Beam Cooling - D.Kayran, NAPAC19

Poster MOPLM18 [1.970 MB]

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reference for this paper ※ https://doi.org/10.18429/JACoW-NAPAC2019-MOPLM18

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paper received ※ 27 August 2019 paper accepted ※ 31 August 2019 issue date ※ 08 October 2019

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TUZBA1

Commissioning of the Electron Accelerator LEReC for Bunched Beam Cooling

330

D. Kayran, Z. Altinbas, D. Bruno, M.R. Costanzo, K.A. Drees, A.V. Fedotov, W. Fischer, M. Gaowei, D.M. Gassner, X. Gu, R.L. Hulsart, P. Inacker, J.P. Jamilkowski, Y.C. Jing, J. Kewisch, C.J. Liaw, C. Liu, J. Ma, K. Mernick, T.A. Miller, M.G. Minty, L.K. Nguyen, M.C. Paniccia, I. Pinayev, V. Ptitsyn, V. Schoefer, S. Seletskiy, F. Severino, T.C. Shrey, L. Smart, K.S. Smith, A. Sukhanov, P. Thieberger, J.E. Tuozzolo, E. Wang, G. Wang, W. Xu, A. Zaltsman, H. Zhao, Z. Zhao
BNL, Upton, New York, USA

Funding: Work supported by Brookhaven Science Associates, LLC under Contract No. DE-AC02-98CH10886 with the U.S. Department of Energy.
The brand-new state of the art electron accelerator, LEReC, was built and commissioned at BNL. LEReC accelerator includes a photocathode DC gun, a laser system, a photocathode delivery system, magnets, beam diagnostics, a SRF booster cavity, and a set of Normal Conducting RF cavities to provide sufficient flexibility to tune the beam in the longitudinal phase space. Electron beam quality suitable for cooling in the Relativistic Heavy Ion Collider (RHIC) was achieved [1], which lead to the first demonstration of bunched beam electron cooling of hadron beams [2]. This presentation will discuss commissioning results, achieved beam parameters and performance of the LEReC systems.
[1] D.Kayran et al., First results from Commissioning of LEReC, in Proc of IPAC2019
[2] A.Fedotov et al., First electron cooling of hadron beams using a bunched electron beam, presented at NAPAC2019

Slides TUZBA1 [18.343 MB]

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reference for this paper ※ https://doi.org/10.18429/JACoW-NAPAC2019-TUZBA1

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paper received ※ 27 August 2019 paper accepted ※ 31 August 2019 issue date ※ 08 October 2019

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TUZBB3

Precise Beam Velocity Matching for the Experimental Demonstration of Ion Cooling With a Bunched Electron Beam

356

S. Seletskiy, M. Blaskiewicz, K.A. Drees, A.V. Fedotov, W. Fischer, D.M. Gassner, R.L. Hulsart, D. Kayran, J. Kewisch, K. Mernick, R.J. Michnoff, T.A. Miller, G. Robert-Demolaize, V. Schoefer, H. Song, P. Thieberger, P. Wanderer
BNL, Upton, New York, USA

The first ever electron cooling based on the RF acceleration of electron bunches was experimentally demonstrated on April 5, 2019 at the Low Energy RHIC Electron Cooler (LEReC) at BNL. The critical step in obtaining successful cooling of the Au ion bunches in the RHIC cooling sections was the accurate matching of average longitudinal velocities of electron and ion beams corresponding to a relative error of less than 5·10^-4 in the e-beam momentum. Since the electron beam kinetic energy is just 1.6 MeV, measuring the absolute e-beam energy with sufficient accuracy and eventually achieving the electron-ion velocity matching was a nontrivial task. In this paper we describe our experience with measuring and setting the e-beam energy at LEReC.

Slides TUZBB3 [1.340 MB]

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reference for this paper ※ https://doi.org/10.18429/JACoW-NAPAC2019-TUZBB3

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paper received ※ 26 August 2019 paper accepted ※ 31 August 2019 issue date ※ 08 October 2019

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TUPLO05

Fixed Target Operation at RHIC in 2019

542

C. Liu, I. Blacker, M. Blaskiewicz, K.A. Brown, D. Bruno, K.A. Drees, A.V. Fedotov, W. Fischer, C.J. Gardner, C.E. Giorgio, X. Gu, T. Hayes, H. Huang, R.L. Hulsart, D. Kayran, N.A. Kling, Y. Luo, D. Maffei, G.J. Marr, B. Martin, A. Marusic, K. Mernick, R.J. Michnoff, M.G. Minty, C. Montag, J. Morris, C. Naylor, S. Nemesure, I. Pinayev, S. Polizzo, V.H. Ranjbar, D. Raparia, G. Robert-Demolaize, T. Roser, J. Sandberg, V. Schoefer, F. Severino, T.C. Shrey, K.S. Smith, S. Tepikian, P. Thieberger, A. Zaltsman, K. Zeno, I.Y. Zhang, W. Zhang
BNL, Upton, New York, USA

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.

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reference for this paper ※ https://doi.org/10.18429/JACoW-NAPAC2019-TUPLO05

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paper received ※ 21 August 2019 paper accepted ※ 15 September 2019 issue date ※ 08 October 2019

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THYBA6

Active Pointing Stabilization Techniques Applied to the Low Energy RHIC Electron Cooling Laser Transport at BNL

938

MOPLM22

use link to see paper's listing under its alternate paper code

SUPLH07

use link to see paper's listing under its alternate paper code

L.K. Nguyen, A.J. Curcio, W.J. Eisele, A.V. Fedotov, A. Fernando, W. Fischer, P. Inacker, J.P. Jamilkowski, D. Kayran, K. Kulmatycski, D. Lehn, T.A. Miller, M.G. Minty, A. Sukhanov
BNL, Upton, New York, USA

Funding: Work supported by Brookhaven Science Associates, LLC under Contract No. DE-AC02-98CH10886 with the U.S. Department of Energy.
The electron beam for the Low Energy RHIC electron Cooler (LEReC) at Brookhaven National Laboratory (BNL) is generated by a high-power fiber laser illuminating a photocathode. The pointing stability of the electron beam, which is crucial given its long transport, is highly dependent on the center-of-mass (CoM) stability of the laser spot on the photocathode. For reasons of accessibility during operations, the laser is located outside the accelerator tunnel, and the laser beam is propagated over a total distance of 34 m via three laser tables to the photocathode. The challenges to achieving the required CoM stability of 10 microns RMS on the photocathode include mitigation of the effects of vibrations along the transport and of weather- and season-related environmental effects, while preserving accessibility and diagnostic capabilities. Due to the insufficiency of infrastructure alone in overcoming these challenges, two active laser transport stabilization systems aimed at addressing specific types of position instability were installed during the 2018 Shutdown. After successful commissioning of the full transport in 2018/19, we report on our solutions to these design challenges.

Slides THYBA6 [3.426 MB]

Poster THYBA6 [1.299 MB]

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reference for this paper ※ https://doi.org/10.18429/JACoW-NAPAC2019-THYBA6

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paper received ※ 27 August 2019 paper accepted ※ 31 August 2019 issue date ※ 08 October 2019

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THZBA5

First Electron Cooling of Hadron Beams Using a Bunched Electron Beam

957

A.V. Fedotov, Z. Altinbas, M. Blaskiewicz, J.M. Brennan, D. Bruno, J.C. Brutus, M.R. Costanzo, K.A. Drees, W. Fischer, J.M. Fite, M. Gaowei, D.M. Gassner, X. Gu, J. Halinski, K. Hamdi, L.R. Hammons, T. Hayes, R.L. Hulsart, P. Inacker, J.P. Jamilkowski, Y.C. Jing, P.K. Kankiya, D. Kayran, J. Kewisch, D. Lehn, C.J. Liaw, C. Liu, J. Ma, G.J. Mahler, M. Mapes, A. Marusic, K. Mernick, C. Mi, R.J. Michnoff, T.A. Miller, M.G. Minty, S.K. Nayak, L.K. Nguyen, M.C. Paniccia, I. Pinayev, S. Polizzo, V. Ptitsyn, T. Rao, G. Robert-Demolaize, T. Roser, J. Sandberg, V. Schoefer, S. Seletskiy, F. Severino, T.C. Shrey, L. Smart, K.S. Smith, H. Song, A. Sukhanov, R. Than, P. Thieberger, S.M. Trabocchi, J.E. Tuozzolo, P. Wanderer, E. Wang, G. Wang, D. Weiss, B.P. Xiao, T. Xin, W. Xu, A. Zaltsman, H. Zhao, Z. Zhao
BNL, Upton, New York, USA

Funding: Work supported by the U.S. Department of Energy.
The Low Energy RHIC electron Cooler (LEReC) was recently constructed and commissioned at BNL. The LEReC is the first electron cooler based on the RF acceleration of electron bunches (previous electron coolers all used DC beams). Bunched electron beams are necessary for cooling hadron beams at high energies. The challenges of such an approach include generation of electron beams suitable for cooling, delivery of electron beams of the required quality to the cooling sections without degradation of beam emittances and energy spread, achieving required small angles between electrons and ions in the cooling sections, precise energy matching between the two beams, high-current operation of the electron accelerator, as well as several physics effects related to bunched beam cooling. Following successful commissioning of the electron accelerator in 2018, the focus of the LEReC project in 2019 was on establishing electron-ion interactions and demonstration of cooling process using electron energy of 1.6MeV (ion energy of 3.85GeV/n), which is the lowest energy of interest. Here we report on the first demonstration of Au ion cooling in RHIC using this new approach.

Slides THZBA5 [16.417 MB]

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paper received ※ 16 August 2019 paper accepted ※ 31 August 2019 issue date ※ 08 October 2019

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