EPJ Web of Conferences (Mar 2014)

Beam Diagnostics for Measurements of Antiproton Annihilation Cross Sections at Ultra-low Energy

  • Todoroki K.,
  • Hori M.,
  • Aghai-Khozani H.,
  • Barna D.,
  • Corradini M.,
  • Kobayashi T.,
  • Leali M.,
  • Lodi-Rizzini E.,
  • Mascagna V.,
  • Prest M.,
  • Soter A.,
  • Vallazza E.,
  • Venturelli L.,
  • Zurlo N.,
  • Hayano R.

DOI
https://doi.org/10.1051/epjconf/20146609020
Journal volume & issue
Vol. 66
p. 09020

Abstract

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The ASACUSA (Atomic Spectroscopy And Collisions Using Slow Antiprotons) collaboration of CERN is currently attempting to measure the antiproton-nucleus in-flight annihilation cross sections on thin target foils of C, Pd, and Pt at 130 keV of kinetic energy. The low-energy antiprotons were supplied by the Antiproton Decelerator (AD) and a radio-frequency quadrupole decelerator. For this measurement, a beam profile monitor based on secondary electron emission was developed. Data from this monitor was used to ensure that antiprotons were precisely tuned to the position of an 80-mm-diameter experimental target, by measuring the spatial profile of 200-ns-long beam pulses containing 105 − 106 antiprotons with an active area of 40 mm × 40 mm and a spatial resolution of 4 mm. By using this monitor, we succeeded in finely tuning antiproton beams on the target, and observed some annihilation events originating from the target.