Author: Thieberger, P.
Paper Title Page
MOPF04 RHIC Injection Transport Beam Emittance Measurements 45
 
  • J.Y. Huang
    Duke University, Durham, North Carolina, USA
  • D.M. Gassner, M.G. Minty, S. Tepikian, P. Thieberger, N. Tsoupas, C.M. Zimmer
    BNL, Upton, Long Island, New York, USA
 
  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.  
Export • reference for this paper to ※ LaTeX, ※ Text, ※ IS/RefMan, ※ EndNote (xml)  
 
MOPD02 The Electron Backscattering Detector (eBSD), a New Tool for the Precise Mutual Alignment of the Electron and Ion Beams in Electron Lenses 129
 
  • P. Thieberger, Z. Altinbas, C. Carlson, C. Chasman, M.R. Costanzo, C. Degen, K.A. Drees, W. Fischer, D.M. Gassner, X. Gu, K. Hamdi, J. Hock, Y. Luo, A. Marusic, T.A. Miller, M.G. Minty, C. Montag, A.I. Pikin, S.M. White
    BNL, Upton, Long Island, 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 Relativistic Heavy Ion Collider (RHIC) electron lenses, being commissioned to attain higher polarized proton-proton luminosities by partially compensating the beam-beam effect, require good alignment of the electron and proton beams. These beams propagating in opposite directions in a 5T solenoid have a typical rms width of 300 microns and need to overlap each other over an interaction length of about 2 m with deviations of less than ~50 microns. A new beam diagnostic tool to achieve and maintain this alignment is based on detecting electrons that are backscattered in close encounters with protons. Maximizing the intensity of these electrons ensures optimum beam overlap. The successful commissioning of these devices using 100 GeV/amu gold beams is described. Future developments are discussed that will further improve the sensitivity to small angular deviations.
 
Export • reference for this paper to ※ LaTeX, ※ Text, ※ IS/RefMan, ※ EndNote (xml)  
 
TUPF02 Proposed Pulse Stretching of BPM Signals for the Position Determination of Very Short and Closely Spaced Bunches 294
 
  • P. Thieberger, S.J. Brooks, K. Hamdi, R.L. Hulsart, G.J. Mahler, R.J. Michnoff, M.G. Minty, D. Trbojevic
    BNL, Upton, Long Island, New York, USA
 
  Funding: Work supported by Brookhaven Science Associates, LLC under contract No. DE-AC02-98CH10886 with the U.S. Department of Energy
A proposal for a future ultra relativistic polarized electron-proton collider (eRHIC) is based in part on the transport of multiple electron beams of different energies through two FFAG beam transports around the 3834 m long RHIC tunnel circumference in order to recirculate them through an Energy Recovery Linac for their stepwise acceleration and deceleration. For each of these transports, the beams will travel in a common vacuum chamber, horizontally separated from each other by a few mm. Determining the position of the individual bunches is challenging due to their very short length (~12 ps rms) and their temporal proximity (less than 4 ns in some cases). Providing pulses adequate for accurate sampling is further complicated by the less-than-ideal response of long coaxial cables. Here we propose two approaches to produce enhanced, i.e. stretched pulse shapes of limited duration; one based on specially shaped BPM electrodes and the other one on analog integration of more conventional stripline BPM signals. In both cases, signals can be generated which contain relatively flat portions which should be easier to sample with good precision without requiring picoseconds timing accuracy.
 
Export • reference for this paper to ※ LaTeX, ※ Text, ※ IS/RefMan, ※ EndNote (xml)  
 
WEPF26 The Brookhaven LINAC Isotope Production Facility (BLIP) Raster Scanning Upgrade 608
 
  • R.J. Michnoff, Z. Altinbas, P. Cerniglia, R. Connolly, C. Cullen, C. Degen, D.M. Gassner, R.L. Hulsart, R.F. Lambiase, L.F. Mausner, D. Raparia, P. Thieberger, M. Wilinski
    BNL, Upton, Long Island, New York, USA
 
  Brookhaven National Laboratory’s BLIP facility produces radioisotopes for the nuclear medicine community and industry, and performs research to develop new radioisotopes desired by nuclear medicine investigators. A raster scanning system is being installed to provide a better distribution of the H beam on the targets, allow higher beam intensities to be used, and ultimately increase production yield of the isotopes. The upgrade consists of horizontal and vertical dipole magnets sinusoidally driven at 5 kHz with 90 deg phase separation to produce a circular raster pattern, and a suite of new instrumentation devices to measure beam characteristics and allow adequate machine protection. The instrumentation systems include multi-wire profile monitors, a laser profile monitor, beam current transformers, and a beam position monitor. An overview of the upgrade and project status will be presented.
Work supported by Brookhaven Science Associates, LLC under Contract No. DE-AC02-98CH10886 with the U.S. Department of Energy
 
poster icon Poster WEPF26 [2.002 MB]  
Export • reference for this paper to ※ LaTeX, ※ Text, ※ IS/RefMan, ※ EndNote (xml)