Speaker
Serge Duarte Pinto
(CERN)
Description
The Antiproton Decelerator (AD) at CERN delivers 5.3 MeV antiproton beams to four experiments. Beam profiles have long been measured by multi-wire proportional chambers. These detectors have a limited spatial resolution, and the combined effects of multiple scattering and space charge in the sensitive volume result in severely distorted profiles.
The beam profile detectors of the AD are now being upgraded. We present our development of gaseous detectors based on direct detection of ionization charge, or amplified by a Gas Electron Multiplier (GEM). The distortions seen in profiles measured by the old wire chambers are partly attributed to the readout electronics. We describe modifications to the existing electronics, to make it cope with the fast spill structure of the AD.
Six new detectors have already been installed on the beam lines of two experiments. We present profiles obtained with these detectors and compare them with those of wire chambers. We expect to complete the replacement of all wire chambers in 2012.
Author
Serge Duarte Pinto
(CERN)