TY - CPAPER
AU - Huang, J.Y.
AU - Gassner, D.M.
AU - Minty, M.G.
AU - Tepikian, S.
AU - Thieberger, P.
AU - Tsoupas, N.
AU - Zimmer, C.M.
TI - RHIC Injection Transport Beam Emittance Measurements
J2 - Proc. of IBIC2014
AB - The Alternating Gradient Synchrotron (AGS)-to-Relativistic Heavy Ion Collider (RHIC) transfer line, abbreviated AtR, is an integral component for the transfer of proton and heavy ion bunches from the AGS to RHIC. In this study, using 23.8 GeV proton beams, we focused on factors that may affect the accuracy of emittance measurements that provide information on the quality of the beam injected into RHIC. The method of emittance measurement uses fluorescent screens in the AtR. The factors that may affect the measurement are: background noise, calibration, resolution, and dispersive corrections. Ideal video Offset (black level, brightness) and Gain (contrast) settings were determined for consistent initial conditions in the Flag Profile Monitor (FPM) application. Using this information, we also updated spatial calibrations for the FPM using corresponding fiducial markings and sketches. Resolution error was determined using the Modulation Transfer Function amplitude. To measure the contribution of the beam’s dispersion, we conducted a scan of beam position and size at relevant Beam Position Monitors (BPMs) and Video Profile Monitors (VPMs, or “flags”) by varying the extraction energy with a scan of the RF frequency in the AGS. The combined effects of these factors resulted in slight variations in emittance values, with further analysis suggesting potential discrepancies in the current model of the beam line’s focusing properties. In the process of testing various contributing factors, a system of checks has been established for future studies, providing an efficient, standardized, and reproducible procedure that might encourage greater reliance on the transfer line’s emittance and beam parameter measurements.
PB - JACoW
CY - Geneva, Switzerland
SP - 45
EP - 48
KW - emittance
KW - factory
KW - background
KW - proton
KW - extraction
DA - 2014/10
PY - 2014
SN - 978-3-95450-141-0
UR - http://jacow.org/IBIC2014/papers/mopf04.pdf
ER -