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Title: The Transmission Factor Method: in-situ Characterization of Getter Coated Pipes

Abstract

Particle accelerators and synchrotron light source need low residual pressure during operating conditions. In specific applications like narrow-gap insertion devices, NEG coating has proved to be very effective. ASTM F798-82 standard is the common characterization method for the sorption performance of getters. In the case of getter coated pipes, the measurement is conducted 'offline' on a sample (coupon), suitably positioned inside the chamber to be coated and removed after the process. Although this approach is suitable to guarantee the control of the process, in-situ characterization should be useful to evaluate residual pressure during the operating conditions. A different measurement technique (Transmission Factor Method) is here described. It is based on the measurement of pressures ratio at the inlet and the outlet of a coated pipe, under a flow of test gas. A calibration curve is calculated using a modellistic approach and permits to evaluate sticking probability of the coated surface from the pressure ratio. Preliminary experimental results about the characterization of this getter will be shown. Keywords: Getter sorption measurement.

Authors:
; ; ;  [1]
  1. Saes Getters S.p.A., Viale Italia 77, 20020 Lainate (Italy)
Publication Date:
OSTI Identifier:
21052547
Resource Type:
Journal Article
Resource Relation:
Journal Name: AIP Conference Proceedings; Journal Volume: 879; Journal Issue: 1; Conference: 9. international conference on synchrotron radiation instrumentation, Daegu (Korea, Republic of), 28 May - 2 Jun 2006; Other Information: DOI: 10.1063/1.2436092; (c) 2007 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND TECHNOLOGY; CALIBRATION; COATINGS; CONTROL; GETTERS; LIGHT SOURCES; MEASURING METHODS; PERFORMANCE; PIPES; PRESSURE MEASUREMENT; SORPTION; SYNCHROTRON RADIATION; SYNCHROTRONS

Citation Formats

Bonucci, Antonio, Conte, Andrea, Manini, Paolo, and Raimondi, Stefano. The Transmission Factor Method: in-situ Characterization of Getter Coated Pipes. United States: N. p., 2007. Web. doi:10.1063/1.2436092.
Bonucci, Antonio, Conte, Andrea, Manini, Paolo, & Raimondi, Stefano. The Transmission Factor Method: in-situ Characterization of Getter Coated Pipes. United States. doi:10.1063/1.2436092.
Bonucci, Antonio, Conte, Andrea, Manini, Paolo, and Raimondi, Stefano. Fri . "The Transmission Factor Method: in-situ Characterization of Getter Coated Pipes". United States. doi:10.1063/1.2436092.
@article{osti_21052547,
title = {The Transmission Factor Method: in-situ Characterization of Getter Coated Pipes},
author = {Bonucci, Antonio and Conte, Andrea and Manini, Paolo and Raimondi, Stefano},
abstractNote = {Particle accelerators and synchrotron light source need low residual pressure during operating conditions. In specific applications like narrow-gap insertion devices, NEG coating has proved to be very effective. ASTM F798-82 standard is the common characterization method for the sorption performance of getters. In the case of getter coated pipes, the measurement is conducted 'offline' on a sample (coupon), suitably positioned inside the chamber to be coated and removed after the process. Although this approach is suitable to guarantee the control of the process, in-situ characterization should be useful to evaluate residual pressure during the operating conditions. A different measurement technique (Transmission Factor Method) is here described. It is based on the measurement of pressures ratio at the inlet and the outlet of a coated pipe, under a flow of test gas. A calibration curve is calculated using a modellistic approach and permits to evaluate sticking probability of the coated surface from the pressure ratio. Preliminary experimental results about the characterization of this getter will be shown. Keywords: Getter sorption measurement.},
doi = {10.1063/1.2436092},
journal = {AIP Conference Proceedings},
number = 1,
volume = 879,
place = {United States},
year = {Fri Jan 19 00:00:00 EST 2007},
month = {Fri Jan 19 00:00:00 EST 2007}
}
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