skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: RHIC Injection Kicker Measurement and Emittance Growth Simulation

Abstract

RHIC operations with gold beams at energies below the design injection energy of 10.5 GeV/N requires the injection of long bunches to mitigate the effects of IBS and space charge [1]. Bunch lengths can be up to 60 ns in length at 3.85 GeV/N (to be compared to normal 35 ns proton bunch e s at 25 GeV). Injection of such long bunches requires revisiting the details of the injection magnet pulse to insure sufficient transfer efficiency from the AGS to RHIC. This note details beam-based measurements of the deflection provided by the injection kicker magnet as a function of bunch arrival time using two different terminating resistors: a 25 Ω resistor, which has been standard for several years, and a 40 Ω resistor, which more nearly represents a matched termination. The measured deflection curves are then used as inputs into a simple simulation to estimate the effects of the kicker rise time and shape (flatness) on the transverse emittance of the injected and circulating bunches. The simulat ions indicate that there is a 12 % intrinsic vertical emittance growth associated with the standard 25 Ω kicker configuration not only for the long low energy bunches, but also for nominalmore » 35 ns long polarized proton bunches at the nominal 25 GeV injection energy.« less

Authors:
 [1]
  1. Brookhaven National Lab. (BNL), Upton, NY (United States)
Publication Date:
Research Org.:
Brookhaven National Laboratory (BNL), Upton, NY (United States)
Sponsoring Org.:
USDOE Office of Science (SC), Nuclear Physics (NP) (SC-26)
OSTI Identifier:
1459174
Report Number(s):
C-A/AP/606; BNL-207810-2018-TECH
DOE Contract Number:  
SC0012704
Resource Type:
Technical Report
Country of Publication:
United States
Language:
English
Subject:
43 PARTICLE ACCELERATORS

Citation Formats

Schoefer, Vincent. RHIC Injection Kicker Measurement and Emittance Growth Simulation. United States: N. p., 2018. Web. doi:10.2172/1459174.
Schoefer, Vincent. RHIC Injection Kicker Measurement and Emittance Growth Simulation. United States. doi:10.2172/1459174.
Schoefer, Vincent. Fri . "RHIC Injection Kicker Measurement and Emittance Growth Simulation". United States. doi:10.2172/1459174. https://www.osti.gov/servlets/purl/1459174.
@article{osti_1459174,
title = {RHIC Injection Kicker Measurement and Emittance Growth Simulation},
author = {Schoefer, Vincent},
abstractNote = {RHIC operations with gold beams at energies below the design injection energy of 10.5 GeV/N requires the injection of long bunches to mitigate the effects of IBS and space charge [1]. Bunch lengths can be up to 60 ns in length at 3.85 GeV/N (to be compared to normal 35 ns proton bunch e s at 25 GeV). Injection of such long bunches requires revisiting the details of the injection magnet pulse to insure sufficient transfer efficiency from the AGS to RHIC. This note details beam-based measurements of the deflection provided by the injection kicker magnet as a function of bunch arrival time using two different terminating resistors: a 25 Ω resistor, which has been standard for several years, and a 40 Ω resistor, which more nearly represents a matched termination. The measured deflection curves are then used as inputs into a simple simulation to estimate the effects of the kicker rise time and shape (flatness) on the transverse emittance of the injected and circulating bunches. The simulat ions indicate that there is a 12 % intrinsic vertical emittance growth associated with the standard 25 Ω kicker configuration not only for the long low energy bunches, but also for nominal 35 ns long polarized proton bunches at the nominal 25 GeV injection energy.},
doi = {10.2172/1459174},
journal = {},
number = ,
volume = ,
place = {United States},
year = {Fri Jun 29 00:00:00 EDT 2018},
month = {Fri Jun 29 00:00:00 EDT 2018}
}

Technical Report:

Save / Share: