A quadratic potential time-of-flight mass spectrometer for use with slow positron ionization sources and other large-volume ion sources

Journal Article · Sun Sep 01 00:00:00 EDT 1991 · Review of Scientific Instruments; (United States)

DOI:https://doi.org/10.1063/1.1142327· OSTI ID:5472431

Hulett, Jr, L D; Donohue, D L; Lewis, T A ^[1]

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1. Oak Ridge National Laboratory, Oak Ridge, Tennessee (USA)

A time-of-flight spectrometer has been specially designed for measuring the masses of ions produced by low-energy positrons interacting with organic molecules in a Penning trap. To make the flight times insensitive to the starting positions of the ions in the trap, acceleration was done using a potential that varied as the square of the distance of the ion from the detector. The containment of the positrons in the Penning trap for extended time periods effected very long collision paths between the positrons and the molecules. The entire length of the Penning trap source could be sampled. These features produced high sensitivity, enabling the measurement of ionization processes with small cross sections. The spectrometer is useful for mass spectrometry of ions produced by processes other than positron interaction. Both large and small volume sources can be accommodated.

• DOE Contract Number: AC05-84OR21400
• OSTI ID: 5472431
• Journal Information: Review of Scientific Instruments; (United States), Vol. 62:9; ISSN 0034-6748
• Country of Publication: United States
• Language: English

Related Subjects

46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND TECHNOLOGY
MASS SPECTROMETERS
PENNING ION SOURCES
POSITRON SOURCES
SENSITIVITY
TIME-OF-FLIGHT METHOD
TRAPS
ION SOURCES
MEASURING INSTRUMENTS
PARTICLE SOURCES
RADIATION SOURCES
SPECTROMETERS
440101* - Radiation Instrumentation- General Detectors or Monitors & Radiometric Instruments