Positron lifetime spectrometer using a DC positron beam

Title: Positron lifetime spectrometer using a DC positron beam

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Abstract

An entrance grid is positioned in the incident beam path of a DC beam positron lifetime spectrometer. The electrical potential difference between the sample and the entrance grid provides simultaneous acceleration of both the primary positrons and the secondary electrons. The result is a reduction in the time spread induced by the energy distribution of the secondary electrons. In addition, the sample, sample holder, entrance grid, and entrance face of the multichannel plate electron detector assembly are made parallel to each other, and are arranged at a tilt angle to the axis of the positron beam to effectively separate the path of the secondary electrons from the path of the incident positrons.

Inventors:: Xu, Jun; Moxom, Jeremy

Issue Date:: 2003-10-21

Research Org.:: Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

Sponsoring Org.:: USDOE

OSTI Identifier:: 1174542

Patent Number(s):: 6,635,871

Application Number:: 09/894,776

Assignee:: UT-Battelle, LLC (Oak Ridge, TN) ORNL

DOE Contract Number:: AC05-00OR22725

Resource Type:: Patent

Country of Publication:: United States

Language:: English

Subject:: 46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND TECHNOLOGY

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                    Xu, Jun, and Moxom, Jeremy. Positron lifetime spectrometer using a DC positron beam.  United States: N. p., 2003. 
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                    Xu, Jun, & Moxom, Jeremy. Positron lifetime spectrometer using a DC positron beam.  United States.

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                    Xu, Jun, and Moxom, Jeremy. Tue .  
        "Positron lifetime spectrometer using a DC positron beam".  United States.  https://www.osti.gov/servlets/purl/1174542.

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@article{osti_1174542,

  title        = {Positron lifetime spectrometer using a DC positron beam},

  author       = {Xu, Jun and Moxom, Jeremy},

  abstractNote = {An entrance grid is positioned in the incident beam path of a DC beam positron lifetime spectrometer. The electrical potential difference between the sample and the entrance grid provides simultaneous acceleration of both the primary positrons and the secondary electrons. The result is a reduction in the time spread induced by the energy distribution of the secondary electrons. In addition, the sample, sample holder, entrance grid, and entrance face of the multichannel plate electron detector assembly are made parallel to each other, and are arranged at a tilt angle to the axis of the positron beam to effectively separate the path of the secondary electrons from the path of the incident positrons.},

  doi          = {},

  journal      = {},
number       = ,

  volume       = ,

  place        = {United States},

  year         = {2003},

  month        = {10}

}

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