Background neutral veto: Background reduction in eta(c) --> gamma-gamma

Technical Report · Mon Jun 01 04:00:00 EDT 1992

DOI:https://doi.org/10.2172/875508· OSTI ID:875508

Marchetto, F

Several upgrades of the E760 detector have been discussed at various stages. One of these considered the possibility of covering with a photon detector the backward region (i.e. lab. poar angle {theta}{sub lab} > 70{sup o}). In this memo the author limited the study to the effect of an extensive coverage in the backward region on the {gamma}{gamma} background at the {eta}{sub c}. This is a rather important channel. In effect at this time and as far as the author knows, they don't have a clear signal and the Signal/Background ratio is poor. (Signal/Background {approx_equal} 1. {divided_by} 1.5 are the values so far obtained from different analyses). Nevertheless the {gamma}{gamma} final state remains the ''strong channel'' for the {eta}{sub c} detection. The author considered as background sources the {pi}{sup 0}{pi}{sup 0} and {pi}{sup 0}{gamma} final states and the author required |cos{theta}*| < 0.25. Events p{bar p} {yields} {pi}{sup 0}{pi}{sup 0} and {pi}{sup 0}{gamma} were Monte Carlo generated at E{sub CM} = 2.985 GeV with the angular distribution as measured by E760 [1].

• Research Organization: Fermi National Accelerator Laboratory (FNAL), Batavia, IL
• Sponsoring Organization: USDOE
• DOE Contract Number: AC02-76CH03000
• OSTI ID: 875508
• Report Number(s): FERMILAB-TM-2333-E
• Country of Publication: United States
• Language: English

Related Subjects

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS
ANGULAR DISTRIBUTION
DETECTION
Experiment-HEP
PHOTONS