TY - JOUR
T1 - Collection of Photoelectrons and operating parameters of CSI photocathode gem detectors
AU - Azmoun, B.
AU - Caccavano, A.
AU - Citron, Z.
AU - Durham, M.
AU - Hemmick, T.
AU - Kamin, J.
AU - Rumore, M.
AU - Woody, C.
N1 - Funding Information:
Manuscript received January 01, 2009; revised April 02, 2009. Current version published June 17, 2009. This work was supported by the U.S. Department of Energy, Division of Nuclear Physics, under Prime Contract DE-AC02-98CH10886. B. Azmoun, A. Caccavano, and C. Woody are with Brookhaven National Laboratory, Upton, NY 11973-5000 USA (e-mail: [email protected]). Z. Citron, M. Durham, T. Hemmick, and J. Kamin are with Stony Brook University, Stony Brook, NY 11794 USA. M. Rumore is with Woster Polytechnic Institute, Woster, MA 01609-2280 USA. Color versions of one or more of the figures in this paper are available online at http://ieeexplore.ieee.org. Digital Object Identifier 10.1109/TNS.2009.2020983 Fig. 1. The absolute quantum efficiency of several typical CsI photocathodes measured in vacuum and in pure CF in parallel plate collection mode. (Measurements performed at Weizmann Institute of Science [10] and Brookhaven National Lab.)
PY - 2009/6/1
Y1 - 2009/6/1
N2 - A study has been made of the parameters affecting the extraction and collection of photoelectrons from the surface of a CsI photocathode in a triple GEM detector. The purpose of this study was to optimize the photoelectron collection efficiency and GEM operating conditions for the PHENIX Hadron Blind Detector (HBD) at RHIC. The parameters investigated include the electric field at the surface of the photocathode, the voltage across the GEM, the electric field below the GEM, the medium into which the photoelectrons are extracted (gas or vacuum), and the wavelength dependence of the extraction efficiency. A small, calibrated light source, or scintillation cube was used to illuminate a GEM CsI photocathode with a known photon flux produced by the scintillation light from 5.48 MeV alpha particles in CF4. The photoelectron collection efficiency was calculated by comparing the number of photoelectrons produced to the number collected at the GEM readout pad. Results are presented on the study of the arameters affecting the photoelectron collection efficiency and the construction and calibration of the scintillation cube.
AB - A study has been made of the parameters affecting the extraction and collection of photoelectrons from the surface of a CsI photocathode in a triple GEM detector. The purpose of this study was to optimize the photoelectron collection efficiency and GEM operating conditions for the PHENIX Hadron Blind Detector (HBD) at RHIC. The parameters investigated include the electric field at the surface of the photocathode, the voltage across the GEM, the electric field below the GEM, the medium into which the photoelectrons are extracted (gas or vacuum), and the wavelength dependence of the extraction efficiency. A small, calibrated light source, or scintillation cube was used to illuminate a GEM CsI photocathode with a known photon flux produced by the scintillation light from 5.48 MeV alpha particles in CF4. The photoelectron collection efficiency was calculated by comparing the number of photoelectrons produced to the number collected at the GEM readout pad. Results are presented on the study of the arameters affecting the photoelectron collection efficiency and the construction and calibration of the scintillation cube.
KW - Cintillation detectors
KW - GEM detectors
KW - Micropattern gas chambers
KW - Photocathodes,photodetectors
KW - Ultraviolet detectors
UR - http://www.scopus.com/inward/record.url?scp=67649158955&partnerID=8YFLogxK
U2 - 10.1109/TNS.2009.2020983
DO - 10.1109/TNS.2009.2020983
M3 - Article
AN - SCOPUS:67649158955
SN - 0018-9499
VL - 56
SP - 1544
EP - 1549
JO - IEEE Transactions on Nuclear Science
JF - IEEE Transactions on Nuclear Science
IS - 3
M1 - 5075967
ER -