New method for the determination of accurate gamma-ray intensities for the 14N(n,{gamma})15N high energy standard
Abstract
The 14N(n,{gamma})15N reaction is a primary source of high energy gamma-rays for use in calibration of detectors for other neutron-capture reactions. The gamma ray-intensities of 15N produced by thermal neutron capture and the gamma-ray detection efficiency function have been simultaneously determined from gamma peak areas alone using the basic principle of an intensity balance. A least square fit was made to a new type of intensity balance calculation, combined with traditional efficiency fitting of radioactive sources. This latter ensures the compatibility with low energy efficiencies, while providing an unbiased efficiency function for higher (up to 10 MeV) gamma-ray energies. The calculation is based on the assumption that the 15N decay scheme is complete. From the internal consistency of the resulting intensities, it is believed that they are more accurate than previously published values. The same is true for the derived efficiency function.
- Authors:
- Institute of Isotopes, Chemical Research Centre, HAS H-1525 Budapest (Hungary)
- Publication Date:
- OSTI Identifier:
- 20798355
- Resource Type:
- Journal Article
- Resource Relation:
- Journal Name: AIP Conference Proceedings; Journal Volume: 819; Journal Issue: 1; Conference: 12. international symposium on capture gamma-ray spectroscopy and related topics, Notre Dame, IN (United States), 4-9 Sep 2005; Other Information: DOI: 10.1063/1.2187920; (c) 2006 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA)
- Country of Publication:
- United States
- Language:
- English
- Subject:
- 73 NUCLEAR PHYSICS AND RADIATION PHYSICS; CALIBRATION; CAPTURE; ENERGY EFFICIENCY; GAMMA DETECTION; GAMMA RADIATION; LEAST SQUARE FIT; MEV RANGE; NEUTRON REACTIONS; NITROGEN 14; NITROGEN 14 TARGET; NITROGEN 15; NUCLEAR DECAY; RADIATION SOURCES; THERMAL NEUTRONS
Citation Formats
Belgya, T. New method for the determination of accurate gamma-ray intensities for the 14N(n,{gamma})15N high energy standard. United States: N. p., 2006.
Web. doi:10.1063/1.2187920.
Belgya, T. New method for the determination of accurate gamma-ray intensities for the 14N(n,{gamma})15N high energy standard. United States. doi:10.1063/1.2187920.
Belgya, T. Mon .
"New method for the determination of accurate gamma-ray intensities for the 14N(n,{gamma})15N high energy standard". United States.
doi:10.1063/1.2187920.
@article{osti_20798355,
title = {New method for the determination of accurate gamma-ray intensities for the 14N(n,{gamma})15N high energy standard},
author = {Belgya, T.},
abstractNote = {The 14N(n,{gamma})15N reaction is a primary source of high energy gamma-rays for use in calibration of detectors for other neutron-capture reactions. The gamma ray-intensities of 15N produced by thermal neutron capture and the gamma-ray detection efficiency function have been simultaneously determined from gamma peak areas alone using the basic principle of an intensity balance. A least square fit was made to a new type of intensity balance calculation, combined with traditional efficiency fitting of radioactive sources. This latter ensures the compatibility with low energy efficiencies, while providing an unbiased efficiency function for higher (up to 10 MeV) gamma-ray energies. The calculation is based on the assumption that the 15N decay scheme is complete. From the internal consistency of the resulting intensities, it is believed that they are more accurate than previously published values. The same is true for the derived efficiency function.},
doi = {10.1063/1.2187920},
journal = {AIP Conference Proceedings},
number = 1,
volume = 819,
place = {United States},
year = {Mon Mar 13 00:00:00 EST 2006},
month = {Mon Mar 13 00:00:00 EST 2006}
}
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