Second gadolinium loading to Super-Kamiokande

Collapse authors list.
Abe, K, Bronner, C, Hayato, Y, Hiraide, K, Hosokawa, K, Ieki, K, Ikeda, M, Kameda, J, Kanemura, Y, Kaneshima, R et al (show 240 more authors) , Kashiwagi, Y, Kataoka, Y, Miki, S, Mine, S, Miura, M, Moriyama, S, Nakano, Y, Nakahata, M, Nakayama, S, Noguchi, Y, Sato, K, Sekiya, H, Shiba, H, Shimizu, K, Shiozawa, M, Sonoda, Y, Suzuki, Y, Takeda, A, Takemoto, Y, Tanaka, H, Yano, T, Han, S, Kajita, T, Okumura, K, Tashiro, T, Tomiya, T, Wang, X, Yoshida, S, Fernandez, P, Labarga, L, Ospina, N, Zaldivar, B, Pointon, BW, Kearns, E, Raaf, JL, Wan, L, Wester, T, Bian, J, Griskevich, NJ, Smy, MB, Sobel, HW, Takhistov, V, Yankelevich, A, Hill, J, Jang, MC, Lee, SH, Moon, DH, Park, RG, Bodur, B, Scholberg, K, Walter, CW, Beauchêne, A, Drapier, O, Giampaolo, A, Mueller, Th A, Santos, AD, Paganini, P, Quilain, B, Rogly, R, Nakamura, T, Jang, JS, Machado, LN, Learned, JG, Choi, K, Iovine, N, Cao, S, Anthony, LHV, Martin, D, Prouse, NW, Scott, M, Uchida, Y, Berardi, V, Calabria, NF, Catanesi, MG, Radicioni, E, Langella, A, De Rosa, G, Collazuol, G, Iacob, F, Mattiazzi, M, Ludovici, L, Gonin, M, Périssé, L, Pronost, G, Fujisawa, C, Maekawa, Y, Nishimura, Y, Okazaki, R, Akutsu, R, Friend, M, Hasegawa, T, Ishida, T, Kobayashi, T, Jakkapu, M, Matsubara, T, Nakadaira, T, Nakamura, K, Oyama, Y, Sakashita, K, Sekiguchi, T, Tsukamoto, T, Bhuiyan, N, Burton, GT, Di Lodovico, F, Gao, J, Goldsack, A, Katori, T, Migenda, J, Ramsden, RM, Xie, Z, Zsoldos, S, Suzuki, AT, Takagi, Y, Takeuchi, Y, Zhong, H, Feng, J, Feng, L, Hu, JR, Hu, Z, Kawaue, M, Kikawa, T, Mori, M, Nakaya, T, Wendell, RA, Yasutome, K, Jenkins, SJ ORCID: 0000-0002-0982-8141, McCauley, N ORCID: 0000-0002-5982-5125, Mehta, P, Tarant, A, Wilking, MJ, Fukuda, Y, Itow, Y, Menjo, H, Ninomiya, K, Yoshioka, Y, Lagoda, J, Mandal, M, Mijakowski, P, Prabhu, YS, Zalipska, J, Jia, M, Jiang, J, Shi, W, Yanagisawa, C, Harada, M, Hino, Y, Ishino, H, Koshio, Y, Nakanishi, F, Sakai, S, Tada, T, Tano, T, Ishizuka, T, Barr, G, Barrow, D, Cook, L, Samani, S, Wark, D, Holin, A, Nova, F, Jung, S, Yang, BS, Yang, JY, Yoo, J, Fannon, JEP, Kneale, L, Malek, M, McElwee, JM, Thiesse, MD, Thompson, LF, Wilson, ST, Okazawa, H, Lakshmi, SM, Kim, SB, Kwon, E, Seo, JW, Yu, I, Ichikawa, AK, Nakamura, K, Tairafune, S, Nishijima, K, Eguchi, A, Nakagiri, K, Nakajima, Y, Shima, S, Taniuchi, N, Watanabe, E, Yokoyama, M, de Perio, P, Fujita, S, Jesús-Valls, C, Martens, K, Tsui, KM, Vagins, MR, Xia, J, Izumiyama, S, Kuze, M, Matsumoto, R, Terada, K, Ishitsuka, M, Ito, H, Ommura, Y, Shigeta, N, Shinoki, M, Yamauchi, K, Yoshida, T, Gaur, R, Gousy-Leblanc, V, Hartz, M, Konaka, A, Li, X, Chen, S, Xu, BD, Zhang, B, Posiadala-Zezula, M, Boyd, SB, Edwards, R, Hadley, D, Nicholson, M, O’Flaherty, M, Richards, B, Ali, A, Jamieson, B, Amanai, S, Marti, Ll, Minamino, A, Suzuki, S, Scovell, PR, Meehan, E, Bandac, I, Peña-Garay, C, Pérez, J, Gileva, O, Lee, EK, Leonard, DS, Sakakieda, Y, Sakaguchi, A, Sueki, K, Takaku, Y and Yamasaki, S (2024) Second gadolinium loading to Super-Kamiokande Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, 1065. p. 169480. ISSN 0168-9002, 1872-9576

Access the full-text of this item by clicking on the Open Access link.

Abstract

The first loading of gadolinium (Gd) into Super-Kamiokande in 2020 was successful, and the neutron capture efficiency on Gd reached 50%. To further increase the Gd neutron capture efficiency to 75%, 26.1 tons of Gd<inf>2</inf>(SO<inf>4</inf>)<inf>3</inf>⋅8H<inf>2</inf>O was additionally loaded into Super-Kamiokande (SK) from May 31 to July 4, 2022. As the amount of loaded Gd<inf>2</inf>(SO<inf>4</inf>)<inf>3</inf>⋅8H<inf>2</inf>O was doubled compared to the first loading, the capacity of the powder dissolving system was doubled. We also developed new batches of gadolinium sulfate with even further reduced radioactive impurities. In addition, a more efficient screening method was devised and implemented to evaluate these new batches of Gd<inf>2</inf>(SO<inf>4</inf>)<inf>3</inf>⋅8H<inf>2</inf>O. Following the second loading, the Gd concentration in SK was measured to be 333.5±2.5 ppm via an Atomic Absorption Spectrometer (AAS). From the mean neutron capture time constant of neutrons from an Am/Be calibration source, the Gd concentration was independently measured to be 332.7 ± 6.8(sys.) ± 1.1(stat.) ppm, consistent with the AAS result. Furthermore, during the loading the Gd concentration was monitored continually using the capture time constant of each spallation neutron produced by cosmic-ray muons, and the final neutron capture efficiency was shown to become 1.5 times higher than that of the first loaded phase, as expected.

Item Type:	Article
Uncontrolled Keywords:	Water Cherenkov detector, Neutrino, Gadolinium, Neutron
Divisions:	Faculty of Science & Engineering Faculty of Science & Engineering > School of Physical Sciences
Depositing User:	Symplectic Admin
Date Deposited:	12 Dec 2024 10:39
Last Modified:	28 Feb 2026 00:46
DOI:	10.1016/j.nima.2024.169480
Open Access URL:	https://www.sciencedirect.com/science/article/pii/...
Related Websites:	Author Publisher
URI:	https://livrepository.liverpool.ac.uk/id/eprint/3189121
Disclaimer:	The University of Liverpool is not responsible for content contained on other websites from links within repository metadata. Please contact us if you notice anything that appears incorrect or inappropriate.