First measurement of the yield of $^8$He isotopes produced in liquid scintillator by cosmic-ray muons at Daya Bay

Author:

Daya Bay Collaboration, F. P. An, W. D. Bai, A. B. Balantekin, M. Bishai, S. Blyth, G. F. Cao, J. Cao, J. F. Chang, Y. Chang, H. S. Chen, H. Y. Chen, S. M. Chen, Y. Chen, Y. X. Chen, Z. Y. Chen, J. Cheng, Y. C. Cheng, Z. K. Cheng, J. J. Cherwinka, M. C. Chu, J. P. Cummings, O. Dalager, F. S. Deng, X. Y. Ding, Y. Y. Ding, M. V. Diwan, T. Dohnal, D. Dolzhikov, J. Dove, K. V. Dugas, H. Y. Duyang, D. A. Dwyer, J. P. Gallo, M. Gonchar, G. H. Gong, H. Gong, W. Q. Gu, J. Y. Guo, L. Guo, X. H. Guo, Y. H. Guo, Z. Guo, R. W. Hackenburg, Y. Han, S. Hans, M. He, K. M. Heeger, Y. K. Heng, Y. K. Hor, Y. B. Hsiung, B. Z. Hu, J. R. Hu, T. Hu, Z. J. Hu, H. X. Huang, J. H. Huang, X. T. Huang, Y. B. Huang, P. Huber, D. E. Jaffe, K. L. Jen, X. L. Ji, X. P. Ji, R. A. Johnson, D. Jones, L. Kang, S. H. Kettell, S. Kohn, M. Kramer, T. J. Langford, J. Lee, J. H. C. Lee, R. T. Lei, R. Leitner, J. K. C. Leung, F. Li, H. L. Li, J. J. Li, Q. J. Li, R. H. Li, S. Li, S. Li, S. C. Li, W. D. Li, X. N. Li, X. Q. Li, Y. F. Li, Z. B. Li, H. Liang, C. J. Lin, G. L. Lin, S. Lin, J. J. Ling, J. M. Link, L. Littenberg, B. R. Littlejohn, J. C. Liu, J. L. Liu, J. X. Liu, C. Lu, H. Q. Lu, K. B. Luk, B. Z. Ma, X. B. Ma, X. Y. Ma, Y. Q. Ma, R. C. Mandujano, C. Marshall, K. T. McDonald, R. D. McKeown, Y. Meng, J. Napolitano, D. Naumov, E. Naumova, T. M. T. Nguyen, J. P. Ochoa-Ricoux, A. Olshevskiy, J. Park, S. Patton, J. C. Peng, C. S. J. Pun, F. Z. Qi, M. Qi, X. Qian, N. Raper, J. Ren, C. Morales Reveco, R. Rosero, B. Roskovec, X. C. Ruan, B. Russell, H. Steiner, J. L. Sun, T. Tmej, W. -H. Tse, C. E. Tull, Y. C. Tung, B. Viren, V. Vorobel, C. H. Wang, J. Wang, M. Wang, N. Y. Wang, R. G. Wang, W. Wang, X. Wang, Y. F. Wang, Z. Wang, Z. Wang, Z. M. Wang, H. Y. Wei, L. H. Wei, W. Wei, L. J. Wen, K. Whisnant, C. G. White, H. L. H. Wong, E. Worcester, D. R. Wu, Q. Wu, W. J. Wu, D. M. Xia, Z. Q. Xie, Z. Z. Xing, H. K. Xu, J. L. Xu, T. Xu, T. Xue, C. G. Yang, L. Yang, Y. Z. Yang, H. F. Yao, M. Ye, M. Yeh, B. L. Young, H. Z. Yu, Z. Y. Yu, B. B. Yue, V. Zavadskyi, S. Zeng, Y. Zeng, L. Zhan, C. Zhang, F. Y. Zhang, H. H. Zhang, J. L. Zhang, J. W. Zhang, Q. M. Zhang, S. Q. Zhang, X. T. Zhang, Y. M. Zhang, Y. X. Zhang, Y. Y. Zhang, Z. J. Zhang, Z. P. Zhang, Z. Y. Zhang, J. Zhao, R. Z. Zhao, L. Zhou, H. L. Zhuang, J. H. Zou

Keyword:

Nuclear Experiment, Nuclear Experiment (nucl-ex), High Energy Physics - Experiment (hep-ex)

journal:

date:

2024-02-08 00:00:00

Abstract

Daya Bay presents the first measurement of cosmogenic $^8$He isotope production in liquid scintillator, using an innovative method for identifying cascade decays of $^8$He and its child isotope, $^8$Li. We also measure the production yield of $^9$Li isotopes using well-established methodology. The results, in units of 10$^{-8}\mu^{-1}$g$^{-1}$cm$^{2}$, are 0.307$\pm$0.042, 0.341$\pm$0.040, and 0.546$\pm$0.076 for $^8$He, and 6.73$\pm$0.73, 6.75$\pm$0.70, and 13.74$\pm$0.82 for $^9$Li at average muon energies of 63.9~GeV, 64.7~GeV, and 143.0~GeV, respectively. The measured production rate of $^8$He isotopes is more than an order of magnitude lower than any other measurement of cosmogenic isotope production. It replaces the results of previous attempts to determine the ratio of $^8$He to $^9$Li production that yielded a wide range of limits from 0 to 30\%. The results provide future liquid-scintillator-based experiments with improved ability to predict cosmogenic backgrounds.

PDF: First measurement of the yield of $^8$He isotopes produced in liquid scintillator by cosmic-ray muons at Daya Bay.pdf