Further studies of two-phase avalanche detectors: Electron emission and gamma-ray detection properties

• Published in: Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment Vol. 623; no. 1; pp. 102 - 104
• Main Authors: Bondar, A., Buzulutskov, A., Grebenuk, A., Pavlyuchenko, D., Tikhonov, Y.
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 01.11.2010
• Subjects: Avalanches; Coherent scattering; Detectors; Electric fields; Electron emission; Gas electron multipliers; Ionization; Polyethylene terephthalates; Positron emission tomography; Searching; Two-phase avalanche detectors; Two-phase avalanche detectors; Electron emission; Gas electron multipliers; Positron emission tomography
• ISSN: 0168-9002; 1872-9576
• DOI: 10.1016/j.nima.2010.02.162

Characteristic properties of two-phase avalanche detectors are further studied. Such detectors are relevant in the field of coherent neutrino-nucleus scattering, dark matter search and positron emission tomography (PET). The detectors investigated comprised a liquid Ar, Ar+N2 or Xe layer followed by a multi-GEM multiplier with CsI photocathode operated in saturated vapor. It was found that doping of two-phase Ar with N2 removed the slow electron emission component, existing in two-phase Ar, and enhanced the fast component. The electron emission efficiency was close to 100% both in two-phase Ar and Ar+N2 even at lower electric fields. The detection of 511keV gamma-ray induced signals was demonstrated in two-phase Ar (scintillation signals) and two-phase Xe (ionization signals) avalanche detectors, in connection with PET applications.