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arXiv · 1407.3542

KamLAND-PICO project to search for cosmic dark matter

K. Fushimi·Y. Awatani·H. Ejiri·R. Hazama·H. Ikeda·K. Imagawa·K. Inoue·A. Kozlov·R. Orito·T. Shima·R. Sugawaraand K. Yasuda
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Abstract

KamLAND-PICO project aims to search for WIMPs dark matter by means of NaI(Tl) scintillator. To investigate the WIMPs candidate whose cross section is as small as $10^{-9}$ pb, a pure NaI(Tl) crystal was developed by chemical processing and taking care of surroundings. The concentration of U and Th chain was reduced to $5.4\pm0.9$ ppt and $3.3\pm2.2$ ppt, respectively. It should be remarked that the concentration of $^{210}$Pb which was difficult to reduce reached to the high purity as $58\pm26$ $\mu$Bq/kg.

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K. Fushimi, Y. Awatani, H. Ejiri, R. Hazama, H. Ikeda, K. Imagawa, K. Inoue, A. Kozlov, R. Orito, T. Shima, R. Sugawaraand K. Yasuda. 2014-07-14. KamLAND-PICO project to search for cosmic dark matter. https://arxiv.org/abs/1407.3542

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