Position sensitive detectors in (e,2e) coincidence measurements
The two outgoing electrons from (e,2e) scattering processes are selected by two 180/sup 0/ electrostatic analyzers whose energy dispersed output spectra are detected by microchannel plates followed by resistive anodes. These detectors permit the identification of all multiple coincident events occurring within the dispersal width of the analyzers. It was found that the time difference between the two detectors for correlated events is strongly dependent on the energy of the incident electrons, which consequently causes the time coincidence window to move systematically. This behavior has been accounted for by a model that determines the time taken by an electron to go around a hemispherical analyzer. A description is given of a data collection system that can compensate for the shift in the coincidence spectra and that records all multiple coincidence events with an increase in the overall coincidence count rate of about two orders of magnitude relative to conventional non position sensitive detectors without position sensing. The performance of the system is shown for an (e,2e) spectrum of argon.
- Research Organization:
- Physics Department, University of Western Australia, Nedlands, Perth, Western Australia 6009
- OSTI ID:
- 6738212
- Journal Information:
- Rev. Sci. Instrum.; (United States), Vol. 59:11
- Country of Publication:
- United States
- Language:
- English
Similar Records
Multichannel (e,2e) apparatus
New developments for an electron impact (e,2e)/(e,3e) spectrometer with multiangle collection and multicoincidence detection
Related Subjects
SUPERCONDUCTIVITY AND SUPERFLUIDITY
ELECTRON SPECTROMETERS
BEAM DYNAMICS
DESIGN
ELECTROSTATIC ANALYZERS
POSITION SENSITIVE DETECTORS
COINCIDENCE METHODS
DATA ACQUISITION SYSTEMS
DISPERSION RELATIONS
ELECTRON COLLISIONS
ELECTRON DETECTION
FOILS
THIN FILMS
BEAM ANALYZERS
CHARGED PARTICLE DETECTION
COLLISIONS
COUNTING TECHNIQUES
DETECTION
FILMS
MEASURING INSTRUMENTS
RADIATION DETECTION
RADIATION DETECTORS
SPECTROMETERS
656003* - Condensed Matter Physics- Interactions between Beams & Condensed Matter- (1987-)