skip to main content

SciTech ConnectSciTech Connect

Title: SNS Sample Activation Calculator Flux Recommendations and Validation

The Spallation Neutron Source (SNS) at Oak Ridge National Laboratory (ORNL) uses the Sample Activation Calculator (SAC) to calculate the activation of a sample after the sample has been exposed to the neutron beam in one of the SNS beamlines. The SAC webpage takes user inputs (choice of beamline, the mass, composition and area of the sample, irradiation time, decay time, etc.) and calculates the activation for the sample. In recent years, the SAC has been incorporated into the user proposal and sample handling process, and instrument teams and users have noticed discrepancies in the predicted activation of their samples. The Neutronics Analysis Team validated SAC by performing measurements on select beamlines and confirmed the discrepancies seen by the instrument teams and users. The conclusions were that the discrepancies were a result of a combination of faulty neutron flux spectra for the instruments, improper inputs supplied by SAC (1.12), and a mishandling of cross section data in the Sample Activation Program for Easy Use (SAPEU) (1.1.2). This report focuses on the conclusion that the SAPEU (1.1.2) beamline neutron flux spectra have errors and are a significant contributor to the activation discrepancies. The results of the analysis of the SAPEU (1.1.2)more » flux spectra for all beamlines will be discussed in detail. The recommendations for the implementation of improved neutron flux spectra in SAPEU (1.1.3) are also discussed.« less
Authors:
 [1] ;  [1] ;  [1] ;  [1]
  1. Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States). Spallation Neutron Source (SNS)
Publication Date:
OSTI Identifier:
1185930
Report Number(s):
ORNL/TM--2015/63
KC0402010; ERKCSND; SNS-ISDD-NSD-TR-0003-R00; TRN: US1500323
DOE Contract Number:
AC05-00OR22725
Resource Type:
Technical Report
Research Org:
Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States). Spallation Neutron Source (SNS)
Sponsoring Org:
USDOE Office of Science (SC)
Country of Publication:
United States
Language:
English
Subject:
46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND TECHNOLOGY; 43 PARTICLE ACCELERATORS; COMPUTER CALCULATIONS; ORNL; NEUTRON FLUX; NEUTRON BEAMS; NEUTRON SPECTRA; NEUTRON SOURCES; VALIDATION; RECOMMENDATIONS; SPALLATION; CROSS SECTIONS; ERRORS; IRRADIATION; RADIOACTIVATION; TARGETS