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Title: A fast microchannel plate-scintillator detector for velocity map imaging and imaging mass spectrometry

Abstract

The time resolution achievable using standard position-sensitive ion detectors, consisting of a chevron pair of microchannel plates coupled to a phosphor screen, is primarily limited by the emission lifetime of the phosphor, around 70 ns for the most commonly used P47 phosphor. We demonstrate that poly-para-phenylene laser dyes may be employed extremely effectively as scintillators, exhibiting higher brightness and much shorter decay lifetimes than P47. We provide an extensive characterisation of the properties of such scintillators, with a particular emphasis on applications in velocity-map imaging and microscope-mode imaging mass spectrometry. The most promising of the new scintillators exhibits an electron-to-photon conversion efficiency double that of P47, with an emission lifetime an order of magnitude shorter. The new scintillator screens are vacuum stable and show no signs of signal degradation even over longer periods of operation.

Authors:
; ;  [1];  [2]
  1. Department of Chemistry, Chemistry Research Laboratory, University of Oxford, 12 Mansfield Rd, Oxford OX1 3TA (United Kingdom)
  2. Department of Chemistry, Physical and Theoretical Chemistry Laboratory, University of Oxford, South Parks Rd, Oxford OX1 3QZ (United Kingdom)
Publication Date:
OSTI Identifier:
22253492
Resource Type:
Journal Article
Resource Relation:
Journal Name: Review of Scientific Instruments; Journal Volume: 85; Journal Issue: 2; Other Information: (c) 2014 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND TECHNOLOGY; BRIGHTNESS; ELECTRONS; LIFETIME; MASS SPECTROSCOPY; MICROCHANNEL ELECTRON MULTIPLIERS; PHOSPHORS; SCINTILLATION COUNTERS; TIME RESOLUTION

Citation Formats

Winter, B., King, S. J., Vallance, C., E-mail: claire.vallance@chem.ox.ac.uk, and Brouard, M., E-mail: mark.brouard@chem.ox.ac.uk. A fast microchannel plate-scintillator detector for velocity map imaging and imaging mass spectrometry. United States: N. p., 2014. Web. doi:10.1063/1.4866647.
Winter, B., King, S. J., Vallance, C., E-mail: claire.vallance@chem.ox.ac.uk, & Brouard, M., E-mail: mark.brouard@chem.ox.ac.uk. A fast microchannel plate-scintillator detector for velocity map imaging and imaging mass spectrometry. United States. doi:10.1063/1.4866647.
Winter, B., King, S. J., Vallance, C., E-mail: claire.vallance@chem.ox.ac.uk, and Brouard, M., E-mail: mark.brouard@chem.ox.ac.uk. 2014. "A fast microchannel plate-scintillator detector for velocity map imaging and imaging mass spectrometry". United States. doi:10.1063/1.4866647.
@article{osti_22253492,
title = {A fast microchannel plate-scintillator detector for velocity map imaging and imaging mass spectrometry},
author = {Winter, B. and King, S. J. and Vallance, C., E-mail: claire.vallance@chem.ox.ac.uk and Brouard, M., E-mail: mark.brouard@chem.ox.ac.uk},
abstractNote = {The time resolution achievable using standard position-sensitive ion detectors, consisting of a chevron pair of microchannel plates coupled to a phosphor screen, is primarily limited by the emission lifetime of the phosphor, around 70 ns for the most commonly used P47 phosphor. We demonstrate that poly-para-phenylene laser dyes may be employed extremely effectively as scintillators, exhibiting higher brightness and much shorter decay lifetimes than P47. We provide an extensive characterisation of the properties of such scintillators, with a particular emphasis on applications in velocity-map imaging and microscope-mode imaging mass spectrometry. The most promising of the new scintillators exhibits an electron-to-photon conversion efficiency double that of P47, with an emission lifetime an order of magnitude shorter. The new scintillator screens are vacuum stable and show no signs of signal degradation even over longer periods of operation.},
doi = {10.1063/1.4866647},
journal = {Review of Scientific Instruments},
number = 2,
volume = 85,
place = {United States},
year = 2014,
month = 2
}
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