Absolute detection efficiency of a micro-channel plate detector to x-rays in the 1--100 KeV energy range

Conference · Thu Sep 03 00:00:00 EDT 1992

OSTI ID:6298310

Burginyon, G A; Jacoby, B A; Wobser, J K; Ernst, R D; Ancheta, D S; Tirsell, K G

There is little information in the literature on the performance of working micro-channel plate (MCP) detectors at high x-ray energies. We have measured the absolute efficiency of a microchannel-plate-intensified, subnanosecond, one dimensional unaging x-ray detector developed at LLNL in the 1 to 100 keV range and at 1.25 MeV. The detector consists of a gold photocathode deposited on the front surface of the MCP (optimized for Ni K[sub [alpha]] (x-rays)) to convert x-rays to electrons, an MCP to amplify the electrons, and a fast In:CdS phosphor that converts the electron's kinetic energy to light. The phosphor is coated on fiber-optic faceplate to transmit the light out of the vacuum system. Electrostatic focusing electrodes compress the electron current out of the MCP in one dimension while preserving spatial resolution in the other. The calibration geometry, dictated by a recent experiment, required grazing incidence x-rays (15.6[degree]) onto the MCP detector in order to maximize deliverable current. The experiment also used a second detector made up of 0.071 in. thick BC422 plastic scintillator material from the Bicron corporation. We compare the absolute efficiencies of these two detectors in units of optical W/cm[sup 2] into 4[pi] per x-ray, W/cm[sup 2] incident. At 7.47 keV and 900 volts MCP bias, the MCP detector delivers [approximately]1400 time more light than the scintillator detector.

• Research Organization: Lawrence Livermore National Lab., CA (United States)
• Sponsoring Organization: USDOE; USDOE, Washington, DC (United States)
• DOE Contract Number: W-7405-ENG-48
• OSTI ID: 6298310
• Report Number(s): UCRL-JC-108982; CONF-920792-58; ON: DE93012592
• Resource Relation: Conference: 37. annual Society of Photo-Optical Instrumentation Engineers (SPIE) international symposium on optical and optoelectronic applied science and engineering, San Diego, CA (United States), 19-24 Jul 1992
• Country of Publication: United States
• Language: English

Related Subjects

46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND TECHNOLOGY
MICROCHANNEL ELECTRON MULTIPLIERS
X-RAY DETECTION
RADIATION DETECTORS
CALIBRATION
EFFICIENCY
PHOTOCATHODES
PLASTIC SCINTILLATORS
CATHODES
DETECTION
ELECTRODES
ELECTRON MULTIPLIERS
ELECTRON TUBES
MEASURING INSTRUMENTS
PHOSPHORS
RADIATION DETECTION
440100* - Radiation Instrumentation