Performance of 0. 75 mm pitch MWPC'S operating at high rate

Conference · Sun Jan 01 04:00:00 EST 1989

OSTI ID:6468978

Conetti, S; Kuzminski, J; Marchionni, A; Stairs, D; Arenton, M; Chen, T Y; Cox, B; Delchamps, S; Etemadi, B; Fortney, L

Three Multiwire Proportional Chambers (MWPC) with high rate capability have been constructed for Fermi National Accelerator Laboratory experiment 705 (Charmonium and Direct Photon production by ..pi../sup +-/, p and /bar p/ at 300 GeV/c). Each chamber, with a sensitive area of 308 cm/sup 2/, consists of three anode planes, wound with 12.5 ..mu..m diameter gold-plated tungsten/rhenium wire, facing 25 ..mu..m graphite-coated kapton cathode planes at a distance of 3 mm. Wire spacing in two of the MWPC (PC-B1 and PC-B2) is 0.75 mm and 1.00 mm in the third one (PC-B3). After a few weeks of running on ''Magic Gas'' with a beam flux of up to /approximately/10/sup 7/ particles/cm/sup 2/sec, severe damage occurred to the graphite coating. All cathode planes were replaced by aluminized kapton, and the chambers worked successfully for the next 3 months until the end of the run, when a 10% efficiency drop was observed after a total accumulated charge of /approximately/1 C/cm of sense wire. After the end of the run the chambers were disassembled and inspected. A white deposit with a characteristic ''wire pattern'' etched away from the Al coating was observed in the region of the beam spot. 10 refs., 8 figs., 1 tab.

• Research Organization: Fermi National Accelerator Lab., Batavia, IL (USA)
• DOE Contract Number: AC02-76CH03000
• OSTI ID: 6468978
• Report Number(s): FNAL/C-89/21-E; CONF-881103-47; ON: DE89007483
• Country of Publication: United States
• Language: English

Related Subjects

440104* -- Radiation Instrumentation-- High Energy Physics Instrumentation
46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND TECHNOLOGY
ACCELERATORS
CYCLIC ACCELERATORS
DESIGN
FERMILAB ACCELERATOR
MEASURING INSTRUMENTS
MULTIWIRE PROPORTIONAL CHAMBERS
PERFORMANCE TESTING
PHYSICAL RADIATION EFFECTS
PROPORTIONAL COUNTERS
RADIATION DETECTORS
RADIATION EFFECTS
SYNCHROTRONS
TESTING