Measurement of time-of-flight spectrometer efficiency for light ions at medium energies

Technical Report · Sat Dec 31 04:00:00 EST 1994

OSTI ID:76269

Arps, J H; Weller, R A

Medium energy time-of-flight spectrometry is an effective technique for helium backscattering as well as the elastic recoil detection of hydrogen and other light elements. However, the efficiency of a time-of-flight spectrometer, unlike that of a surface barrier detector, depends strongly on the energy and mass of the detected particle. A thorough understanding of this spectrometer quantum efficiency is necessary for quantitative measurements. The authors report initial measurements of the quantum efficiency of two similar time-of-flight spectrometers in forward and backscattering geometries for hydrogen, helium, and carbon projectiles over the energy range 50-275 keV. The results are compared with predictions of a model which incorporates multiple scattering and secondary electron emission at the carbon start foil along with an energy-independent microchannel plate response. When these processes are taken into account, the efficiency of a spectrometer as a function of projectile species and energy can be described to within experimental error by a single overall calibration constant.

• Research Organization: Vanderbilt Univ., Nashville, TN (United States). Dept. of Physics and Astronomy
• OSTI ID: 76269
• Report Number(s): AD-A--288409/6/XAB; CNN: Contract DAAL03-92-G-0037
• Country of Publication: United States
• Language: English

Related Subjects

44 INSTRUMENTATION
INCLUDING NUCLEAR AND PARTICLE DETECTORS
CALIBRATION
CARBON IONS
HELIUM IONS
HYDROGEN IONS
ION DETECTION
KEV RANGE 10-100
KEV RANGE 100-1000
LIGHT IONS
QUANTUM EFFICIENCY
TIME-OF-FLIGHT MASS SPECTROMETERS