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

Title: Proton Radiography at the AGS

  1. Los Alamos National Laboratory
Publication Date:
Research Org.:
Los Alamos National Lab. (LANL), Los Alamos, NM (United States)
Sponsoring Org.:
OSTI Identifier:
Report Number(s):
DOE Contract Number:
Resource Type:
Resource Relation:
Conference: Transformative uses of hadron beam ; 2014-07-21 - 2014-07-21 ; Upton, New York, United States
Country of Publication:
United States
Instrumentation Related to Nuclear Science & Technology(46); Particle Accelerators(43); Physics of Elementary Particles & Fields(72)

Citation Formats

Saunders, Alexander. Proton Radiography at the AGS. United States: N. p., 2014. Web.
Saunders, Alexander. Proton Radiography at the AGS. United States.
Saunders, Alexander. Fri . "Proton Radiography at the AGS". United States. doi:.
title = {Proton Radiography at the AGS},
author = {Saunders, Alexander},
abstractNote = {},
doi = {},
journal = {},
number = ,
volume = ,
place = {United States},
year = {Fri Jul 25 00:00:00 EDT 2014},
month = {Fri Jul 25 00:00:00 EDT 2014}

Other availability
Please see Document Availability for additional information on obtaining the full-text document. Library patrons may search WorldCat to identify libraries that hold this conference proceeding.

Save / Share:
  • The problem of nuclear stopping power and its importance to the study of nucleus-nucleus collisions at very high energies was brought to general attention one year ago at Quark Matter 83 by Busza and Goldhaber. In this context, nuclear stopping power can be thought of as the rate of energy (or rapidity) loss of a proton traversing nuclear matter. It does not directly address the important question of energy deposition. Busza and Goldhaber showed that knowledge of nuclear stopping power is needed to estimate the minimum center-of-mass energy required in nucleus-nucleus collisions to ensure the production of very high temperaturesmore » at low baryon density. At cm energies of about 1 to 10 GeV/A, the stopping power is important in the estimation of the maximum baryon densities attainable in nucleus-nucleus collisions. The data presented are more relevant to this latter point.« less
  • This report describes the three polarimeters which will be used to measure the beam polarization at the AGS polarized beam facility. The beam polarization will be measured before injection into the AGS, during acceleration, and after extraction from the AGS. The 200 MeV polarimeter uses scintillation counter telescopes to measure the asymmetry in p-carbon inclusive scattering. The internal polarimeter can measure the beam polarization at up to five selected times during acceleration. A continuously spooled nylon filament is swung into the beam at the appropriate time and the asymmetry in pp elastic scattering measured by two scintillation counter telescopes. Thismore » is a relative polarimeter which can be calibrated by the absolute external polarimeter located in the ''D'' extracted beam line. This polarimeter uses scintillation counters in two double-arm magnetic spectrometers to measure clearly the asymmetry in pp elastic scattering from a liquid hydrogen target. The specific features and operation of each polarimeter are discussed.« less
  • The proton driver for the muon collider must produce short pulses of protons in order to facilitate muon cooling and operation with polarized beams. In order to test methods of producing these bunches they have operated the AGS near transition and studied procedures which involved moving the transition energy {gamma} to the beam energy. They were able to produce stable bunches with RMS widths of {sigma} = 2.2-2.7 ns for longitudinal bunch areas of {minus}1.5 V-s, in addition to making measurements of the lowest two orders of the momentum compaction factor.
  • The AGS has been upgraded over the past three years to produce a record beam intensity of 6 {times} 10{sup 13} protons per pulse for the fixed-target physics program. The major elements of the upgrade are: the new 1.5 GeV Booster synchrotron, the main magnet power supply, a high frequency longitudinal dilution cavity, a feedback damper for transverse instabilities, a fast gamma transition jump system, and a new high-power rf system. The new rf system and its role in achieving the high intensity goal are the subjects of this report. The rf system is heavily beam loaded, with 7 Ampsmore » of rf current in the beam and a peak power of 0.75 MW delivered to the beam by ten cavities. As an example of the scale of beam loading, at one point in the acceleration cycle the cavities are operated at 1.5 kV/gap; whereas, were it not for the new power amplifiers, the beam-induced voltage on the cavities would be over 25 kV/gap. The upgraded rf system, comprising: new power amplifiers, wide band rf feedback, improved cavities, and new low-level beam control electronics, is described. Results of measurements with beam, which characterize the system`s performance, are presented. A typical high intensity acceleration cycle is described with emphasis on the key challenges of beam loading.« less