Definition of energy-calibrated spectra for national reachback

Technical Report · Wed Jan 01 00:00:00 EST 2014

DOI:https://doi.org/10.2172/1204077· OSTI ID:1204077

Kunz, Christopher L. ^[1]; Hertz, Kristin L. ^[1]

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1. Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

Accurate energy calibration is critical for the timeliness and accuracy of analysis results of spectra submitted to National Reachback, particularly for the detection of threat items. Many spectra submitted for analysis include either a calibration spectrum using ¹³⁷Cs or no calibration spectrum at all. The single line provided by ¹³⁷Cs is insufficient to adequately calibrate nonlinear spectra. A calibration source that provides several lines that are well-spaced, from the low energy cutoff to the full energy range of the detector, is needed for a satisfactory energy calibration. This paper defines the requirements of an energy calibration for the purposes of National Reachback, outlines a method to validate whether a given spectrum meets that definition, discusses general source considerations, and provides a specific operating procedure for calibrating the GR-135.

• Research Organization: Sandia National Lab. (SNL-CA), Livermore, CA (United States)
• Sponsoring Organization: USDOE National Nuclear Security Administration (NNSA)
• DOE Contract Number: AC04-94AL85000
• OSTI ID: 1204077
• Report Number(s): SAND2014-0686; 498791
• Country of Publication: United States
• Language: English