Report on LEReC Recombination Monitor APEX Study on June 15th 2016

Technical Report · Wed Dec 21 00:00:00 EST 2016

DOI:https://doi.org/10.2172/1338609· OSTI ID:1338609

Drees, A. ^[1]; Bruno, D. ^[1]; Curcio, T. ^[1]; Montag, C. ^[1]; Robert-Demolaize, G. ^[1]; Thieberger, P. ^[1]

---

1. Brookhaven National Lab. (BNL), Upton, NY (United States)

During the prospective Low Energy RHIC electron Cooling (LEReC) operation, the electron beam will overlap and interact with the low energy ion beam to provide transverse cooling. Cooling is needed to facilitate reaching the BES-2 (Beam Energy Scan 2) program goals of an average store luminosity of 5 × 10²⁴ cm^-2 s^-1 at 3.85 GeV/n and 17.3 × 10²⁴ cm^-2 s^-1 at 9.1 GeV/n. The RHIC phase of BES-2 is currently planned for the RHIC runs in 2019 and 2020. Effective cooling will depend on the accuracy of velocity matching between the two beams. Another process, the rate of ion-electron recombination, is also maximized when the velocities are matched, but the exact matching requirement is less stringent. Therefore, as suggested by one of us, detecting and maximizing recombination signals should be helpful in finding the narrow velocity matching window conducive to cooling. When ¹⁹⁷Au⁷⁹⁺ RHIC ions pick up an electron from the LEREeC electron beam they are converted into ¹⁹⁷Au⁷⁸⁺ ions with nearly the same momentum while having about 1.3% higher magnetic rigidity than the original ¹⁹⁷Au⁷⁹⁺ particles. The detection of the recombined ions can be done by driving the ¹⁹⁷Au⁷⁸⁺ beam into the beam pipe wall, creating showers of secondary particles which then can be detected outside the cryostat by using appropriately positioned detectors. For the purpose of forcing losses of the expected off-momentum particles a dedicated lattice with large horizontal dispersion in one arc was proposed and designed.

• Research Organization: Brookhaven National Lab. (BNL), Upton, NY (United States). Relativistic Heavy Ion Collider (RHIC)
• Sponsoring Organization: USDOE Office of Science (SC), Nuclear Physics (NP)
• DOE Contract Number: SC00112704
• OSTI ID: 1338609
• Report Number(s): BNL-113384-2016-IR; R&D Project: KBCH139; KB0202011; TRN: US1701449
• Country of Publication: United States
• Language: English

Related Subjects

43 PARTICLE ACCELERATORS
ELECTRON BEAMS
ION BEAMS
GOLD 197
BROOKHAVEN RHIC
GEV RANGE 100-1000
VELOCITY
RECOMBINATION
MONITORS
ELECTRON COOLING
MAGNETIC RIGIDITY
ACCURACY
DETECTION
BEAM DYNAMICS
Relativistic Heavy Ion Collider