Single-electron pulse-height spectra in thin-gap parallel-plate chambers

Fonte, P Ferreira-Marques, R Peskov, V Policarpo, A

P. Fonte et al., Single-electron pulse-height spectra in thin-gap parallel-plate chambers, NUCL INST A, 433(1-2), 1999, pp. 513-517

8

INGLESE

Article

Spectroscopy /Instrumentation/Analytical Sciences","Instrumentation & Measurement

NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT

0168-9002 → ACNP

433

1-2

1999

513 - 517

ISI

0168-9002(19990821)433:1-2<513:SPSITP>2.0.ZU;2-G

Single-electron pulse-height spectra were measured in 0.6 and 1.2 mm parall el-plate chambers developed for the TOF system of the ALICE/LHC-HI experime nt. Mixtures of Ar with ethane, isobutane, and SF, were studied. The observ ed spectrum shows a clear peak for all gases, suggesting efficient single-e lectron detection in thin parallel-plate structures. The pulse-height spect rum can be described by the weighted sum of an exponential and a Polya dist ribution, the Polya contribution becoming more important at higher gains. A dditionally, it was found that the maximum gain, above 10(6), is limited by the appearance of streamers and depends weakly on the gas composition. The suitability of each mixture for single-electron detection is also quantita tively assessed. (C) 1999 Elsevier Science B.V. All rights reserved.