The effect of neutrons on the background of HPGe detectors operating deep underground

Result code in IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F68407700%3A90107%2F22%3A00363779" target="_blank" >RIV/68407700:90107/22:00363779 - isvavai.cz</a>

Result on the web

<a href="https://doi.org/10.1016/j.astropartphys.2022.102756" target="_blank" >https://doi.org/10.1016/j.astropartphys.2022.102756</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1016/j.astropartphys.2022.102756" target="_blank" >10.1016/j.astropartphys.2022.102756</a>

Result language

angličtina

Original language name

The effect of neutrons on the background of HPGe detectors operating deep underground

Original language description

The background of a High Purity Germanium (HPGe) detector measured in a deep underground laboratory was investigated analytically and by Monte Carlo simulations using the GEANT4 toolkit. Contributions of different background sources to the experimental gamma-ray background were determined. Namely, contribution of radionuclides in materials of the detector and around the detector, neutrons produced by (alpha, n) reactions due to presence of radionuclides in rock and concrete and by spontaneous fission of mainly U-238, and finally, cosmic rays with neutron generation. The simulation, including radionuclides in the material, was in a good agreement with the experiment. At the same time, neutron and muon induced spectra were simulated. The radiation coming from the presence of members of the U-238, and Th-232 decay series, and K-40 in the detector parts and the laboratory walls contribute to the continuum of the experimental spectrum at the level of around 94%. According to simulations, the contribution of muon events to the experimental energy spectrum was below 1% and it was confirmed that muon induced spectra are about three orders of magnitude lower than the experimental one. The comparison of integral count rates of the experimental spectrum with the simulated spectrum induced by neutrons showed that about 6% of the measured background continuum originated from neutron reactions. Fast neutrons contributed more to the background (at around 65%) than thermal neutrons. Despite only a 6% share of neutron contributions in the total gamma-ray background, they contributed mainly to the lower continuum of the spectrum up to 250 keV, which is a region of interest for potential low mass weakly interacting massive particle (WIMP) dark matter interactions. In addition, they interact with the detector and the shield by inelastic scattering and induce unwanted gamma-rays. Neutron capture, elastic and inelastic scattering were simulated separately as well. It was found that inela

Czech name

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Czech description

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Type

J_imp - Article in a specialist periodical, which is included in the Web of Science database

CEP classification

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OECD FORD branch

10304 - Nuclear physics

Project

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Continuities

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Publication year

2022

Confidentiality

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů

Name of the periodical

Astroparticle Physics

ISSN

0927-6505

e-ISSN

1873-2852

Volume of the periodical

143

Issue of the periodical within the volume

102756

Country of publishing house

NL - THE KINGDOM OF THE NETHERLANDS

Number of pages

13

Pages from-to

1-13

UT code for WoS article

000842930500003

EID of the result in the Scopus database

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