Abstract We present the analysis and results of the first datasetcollected with the MARS neutron detectordeployed at the Oak Ridge NationalLaboratory Spallation Neutron Source (SNS) for the purpose ofmonitoring and characterizing the beam-related neutron (BRN) backgroundfor the COHERENT collaboration. MARS was positionednext to the COH-CsI coherent elastic neutrino-nucleus scattering detectorin the SNS basement corridor. This is the basement location ofclosest proximity to the SNS target and thus, of highest neutrino flux,but it is also well shielded from the BRN flux by infill concreteand gravel. These data show the detector registered roughly one BRN per day.Using MARS' measured detection efficiency, the incomingBRN flux is estimated to be 1.20 ± 0.56 neutrons/m^2/MWhfor neutron energies above ∼3.5 MeV and up to a few tens of MeV.We compare our results with previous BRN measurements in the SNS basement corridorreported by other neutron detectors.
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Characterization of D-T generator neutron flux spectrum for cyclic neutron activation analysis experiments
Improving nuclear data for short-lived fission product yields will further our fundamental understanding of fission, which is needed across various scientific fields and applications. One method of attaining the needed product yield data is through cyclic neutron activation, which allows a target to be irradiated in a neutron environment and then transported for counting of the radionuclides produced, typically via g spectroscopy. Recently, such a system was constructed and commissioned at Pacific Northwest National Laboratory. In this system, targets are shuttled between the head of a D-T neutron generator and a counting station with a transit time of about 2 sec. As part of the characterization of this system, the neutron flux was studied using two activation targets. The neutron flux from the deuterium-tritium fusion generator was determined to be 9:95±0:33×108 n/cm2·s with a peak energy of 14.9 MeV and a spread of approximately 4 decades between the epithermal and 14 MeV peak group flux.
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- Award ID(s):
- 1938815
- PAR ID:
- 10556658
- Publisher / Repository:
- AIP Conference Proceedings
- Date Published:
- Page Range / eLocation ID:
- 070003
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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