Radiopurity of NaI(Tl) crystals for PICOLON dark matter experiment

Fuente: arXiv
Saved in:
Bibliographic Details
Main Authors: Kotera, K., Chernyak, D., Ejiri, H., Fushimi, K., Hata, K., Hazama, R., Iida, T., Ikeda, H., Imagawa, K., Inoue, K., Ito, H., Kishimoto, T., Koga, M., Kozlov, A., Nakamura, K., Orito, R., Shima, T., Takemoto, Y., Umehara, S., Urano, Y., Yasuda, K., Yoshida, S.
Format: Preprint
Published: 2023
Subjects:
Online Access:
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1866916412932489216
author Kotera, K.
Chernyak, D.
Ejiri, H.
Fushimi, K.
Hata, K.
Hazama, R.
Iida, T.
Ikeda, H.
Imagawa, K.
Inoue, K.
Ito, H.
Kishimoto, T.
Koga, M.
Kozlov, A.
Nakamura, K.
Orito, R.
Shima, T.
Takemoto, Y.
Umehara, S.
Urano, Y.
Yasuda, K.
Yoshida, S.
author_facet Kotera, K.
Chernyak, D.
Ejiri, H.
Fushimi, K.
Hata, K.
Hazama, R.
Iida, T.
Ikeda, H.
Imagawa, K.
Inoue, K.
Ito, H.
Kishimoto, T.
Koga, M.
Kozlov, A.
Nakamura, K.
Orito, R.
Shima, T.
Takemoto, Y.
Umehara, S.
Urano, Y.
Yasuda, K.
Yoshida, S.
contents The dark matter observation claim by the DAMA/LIBRA collaboration has been a long-standing puzzle within the particle physics community. Efforts of other research groups to verify the claim have been insufficient by significant radioactivity of present NaI(Tl) crystals. PICOLON (Pure Inorganic Crystal Observatory for LOw-energy Neut(ra)lino) experiment conducts independent search for Weakly Interacting Massive Particles (WIMPs) using NaI(Tl) crystals. Our NaI(Tl) crystal manufactured in 2020 (Ingot #85) reached the same purity level as DAMA/LIBRA crystals. In this report, we describe the radiopurity of the new Ingot #94 crystal produced using the same purification technique as Ingot #85. The $α$-ray events were selected by pulse-shape discrimination method. The impurities in the Ingot #94, $^{232}$Th, $^{226}$Ra and $^{210}$Po radioactivity were $4.6\pm 1.2~\mathrm{μBq/kg}$, $7.9\pm 4.4~\mathrm{μBq/kg}$, and $19\pm 6~\mathrm{μBq/kg}$, which are equivalent to those of the DAMA/LIBRA crystals. The background rate in the energy region of 2-6 keV , was 2-5 events/d/kg/keV without applying a veto trigger.
format Preprint
id arxiv_https___arxiv_org_abs_2309_13941
institution arXiv
publishDate 2023
record_format arxiv
spellingShingle Radiopurity of NaI(Tl) crystals for PICOLON dark matter experiment
Kotera, K.
Chernyak, D.
Ejiri, H.
Fushimi, K.
Hata, K.
Hazama, R.
Iida, T.
Ikeda, H.
Imagawa, K.
Inoue, K.
Ito, H.
Kishimoto, T.
Koga, M.
Kozlov, A.
Nakamura, K.
Orito, R.
Shima, T.
Takemoto, Y.
Umehara, S.
Urano, Y.
Yasuda, K.
Yoshida, S.
Instrumentation and Detectors
Instrumentation and Methods for Astrophysics
The dark matter observation claim by the DAMA/LIBRA collaboration has been a long-standing puzzle within the particle physics community. Efforts of other research groups to verify the claim have been insufficient by significant radioactivity of present NaI(Tl) crystals. PICOLON (Pure Inorganic Crystal Observatory for LOw-energy Neut(ra)lino) experiment conducts independent search for Weakly Interacting Massive Particles (WIMPs) using NaI(Tl) crystals. Our NaI(Tl) crystal manufactured in 2020 (Ingot #85) reached the same purity level as DAMA/LIBRA crystals. In this report, we describe the radiopurity of the new Ingot #94 crystal produced using the same purification technique as Ingot #85. The $α$-ray events were selected by pulse-shape discrimination method. The impurities in the Ingot #94, $^{232}$Th, $^{226}$Ra and $^{210}$Po radioactivity were $4.6\pm 1.2~\mathrm{μBq/kg}$, $7.9\pm 4.4~\mathrm{μBq/kg}$, and $19\pm 6~\mathrm{μBq/kg}$, which are equivalent to those of the DAMA/LIBRA crystals. The background rate in the energy region of 2-6 keV , was 2-5 events/d/kg/keV without applying a veto trigger.
title Radiopurity of NaI(Tl) crystals for PICOLON dark matter experiment
topic Instrumentation and Detectors
Instrumentation and Methods for Astrophysics
url https://arxiv.org/abs/2309.13941