Title :
Studies of the effects of oxygen and CO2 contamination of the neon gas radiator on the performance of the NA62 RICH detector
Author :
Gersabeck, Evelina
Author_Institution :
INFN, Sezione di Perugia, Perugia, Italy
Abstract :
The NA62 RICH detector is used for the separation of pions and muons in the momentum range 15-35 GeV/c and is expected to provide a muon suppression factor better than 10-2. A prototype of the final detector equipped with about 400 PMs (RICH-400 prototype) was built and tested in a dedicated run in 2009. The π-μ separation was tested, as well as the effect of the pollution of the neon radiator with different amounts of oxygen and CO2. The μ misidentification probability is about 0.7% and the time resolution better than 100 ps in the whole momentum range. We did not observe any absorption of the light due to the pollution of the radiator, however an effect on the ring radius is clearly observed due to the change of the change of the refractive index of the medium. The conclusion of the studies is that the amount of CO2 in the final detector should be well known or the quality of the pion identification could be seriously compromised.
Keywords :
Cherenkov counters; contamination; kaon decay; neon; semileptonic decays; CO2 contamination; NA62 RICH detector; RICH-400 prototype; kaon decay into pion+neutrino+antineutrino; muon suppression factor; neon gas radiator; pi-mu separation; pion identification; refractive index;
Conference_Titel :
Nuclear Science Symposium and Medical Imaging Conference (NSS/MIC), 2011 IEEE
Conference_Location :
Valencia
Print_ISBN :
978-1-4673-0118-3
DOI :
10.1109/NSSMIC.2011.6154579