Extraction of the ${}^{235}\mathrm{U}$ and ${}^{239}\mathrm{Pu}$ Antineutrino Spectra at Daya Bay

Journal Article · Fri Sep 13 00:00:00 EDT 2019 · Physical Review Letters

DOI:https://doi.org/10.1103/PhysRevLett.123.111801· OSTI ID:1562139

Adey, D.; An, F. P.; Balantekin, A. B.; Band, H. R.; Bishai, M.; Blyth, S.; Cao, D.; Cao, G. F.; Cao, J.; Chang, J. F.; Chang, Y.; Chen, H. S.; Chen, S. M.; Chen, Y.; Chen, Y. X.; Cheng, J.; Cheng, Z. K.; Cherwinka, J. J.; Chu, M. C.; Chukanov, A. ; Cummings, J. P.; Dash, N.; Deng, F. S.; Ding, Y. Y.; Diwan, M. V.; Dohnal, T.; Dove, J.; Dvořák, M.; Dwyer, D. A.; Gonchar, M.; Gong, G. H.; Gong, H.; Gu, W. Q.; Guo, J. Y.; Guo, L.; Guo, X. H.; Guo, Y. H.; Guo, Z.; Hackenburg, R. W.; Hans, S.; He, M.; Heeger, K. M.; Heng, Y. K.; Higuera, A.; Hor, Y. K.; Hsiung, Y. B.; Hu, B. Z.; Hu, J. R.; Hu, T.; Hu, Z. J.; Huang, H. X.; Huang, X. T.; Huang, Y. B.; Huber, P.; Jaffe, D. E.; Jen, K. L.; Ji, X. L.; Ji, X. P.; Johnson, R. A.; Jones, D.; Kang, L.; Kettell, S. H.; Koerner, L. W.; Kohn, S.; Kramer, M.; Langford, T. J.; Lee, J.; Lee, J. H. C.; Lei, R. T.; Leitner, R.; Leung, J. K. C.; Li, C.; Li, F.; Li, H. L.; Li, Q. J.; Li, S.; Li, S. C.; Li, S. J.; Li, W. D.; Li, X. N.; Li, X. Q.; Li, Y. F.; Li, Z. B.; Liang, H.; Lin, C. J.; Lin, G. L.; Lin, S.; Ling, J. J.; Link, J. M.; Littenberg, L.; Littlejohn, B. R.; Liu, J. C.; Liu, J. L.; Liu, Y.; Liu, Y. H.; Lu, C.; Lu, H. Q.; Lu, J. S.; Luk, K. B.; Ma, X. B.; Ma, X. Y.; Ma, Y. Q.; Marshall, C.; Martinez Caicedo, D. A.; McDonald, K. T.; McKeown, R. D.; Mitchell, I.; Mora Lepin, L.; Napolitano, J.; Naumov, D.; Naumova, E.; Ochoa-Ricoux, J. P.; Olshevskiy, A.; Pan, H. -R.; Park, J.; Patton, S.; Pec, V.; Peng, J. C.; Pinsky, L.; Pun, C. S. J.; Qi, F. Z.; Qi, M.; Qian, X.; Raper, N.; Ren, J.; Rosero, R.; Roskovec, B.; Ruan, X. C.; Steiner, H.; Sun, J. L.; Treskov, K.; Tse, W. -H.; Tull, C. E.; Viren, B.; Vorobel, V.; Wang, C. H.; Wang, J.; Wang, M.; Wang, N. Y.; Wang, R. G.; Wang, W.; Wang, W.; Wang, X.; Wang, Y.; Wang, Y. F.; Wang, Z.; Wang, Z.; Wang, Z. M.; Wei, H. Y.; Wei, L. H.; Wen, L. J.; Whisnant, K.; White, C. G.; Wong, H. L. H.; Wong, S. C. F.; Worcester, E.; Wu, Q.; Wu, W. J.; Xia, D. M.; Xing, Z. Z.; Xu, J. L.; Xue, T.; Yang, C. G.; Yang, L.; Yang, M. S.; Yang, Y. Z.; Ye, M.; Yeh, M.; Young, B. L.; Yu, H. Z.; Yu, Z. Y.; Yue, B. B.; Zeng, S.; Zeng, Y.; Zhan, L. ; Zhang, C.; Zhang, C. C.; Zhang, F. Y.; Zhang, H. H.; Zhang, J. W.; Zhang, Q. M.; Zhang, R.; Zhang, X. F.; Zhang, X. T.; Zhang, Y. M.; Zhang, Y. M.; Zhang, Y. X.; Zhang, Y. Y.; Zhang, Z. J.; Zhang, Z. P.; Zhang, Z. Y.; Zhao, J.; Zhou, L.; Zhuang, H. L.; Zou, J. H.

This Letter reports the first extraction of individual antineutrino spectra from ^{235}U and ^{239}Pu fission and an improved measurement of the prompt energy spectrum of reactor antineutrinos at Daya Bay. The analysis uses 3.5×10^{6} inverse beta-decay candidates in four near antineutrino detectors in 1958 days. The individual antineutrino spectra of the two dominant isotopes, ^{235}U and ^{239}Pu, are extracted using the evolution of the prompt spectrum as a function of the isotope fission fractions. In the energy window of 4-6 MeV, a 7% (9%) excess of events is observed for the ^{235}U (^{239}Pu) spectrum compared with the normalized Huber-Mueller model prediction. The significance of discrepancy is 4.0σ for ^{235}U spectral shape compared with the Huber-Mueller model prediction. The shape of the measured inverse beta-decay prompt energy spectrum disagrees with the prediction of the Huber-Mueller model at 5.3σ. In the energy range of 4-6 MeV, a maximal local discrepancy of 6.3σ is observed.

• Research Organization: Brookhaven National Laboratory (BNL), Upton, NY (United States); Illinois Institute of Technology, Chicago, IL (United States); Lawrence Berkeley National Laboratory (LBNL), Berkeley, CA (United States)
• Sponsoring Organization: USDOE Office of Science (SC), High Energy Physics (HEP)
• Contributing Organization: Daya Bay Collaboration
• Grant/Contract Number: SC0012704; SC0008347; AC02-05CH11231
• OSTI ID: 1562139
• Alternate ID(s): OSTI ID: 1570660; OSTI ID: 1595051; OSTI ID: 1737576
• Report Number(s): BNL-212199-2019-JAAM; PRLTAO; 111801
• Journal Information: Physical Review Letters, Journal Name: Physical Review Letters Vol. 123 Journal Issue: 11; ISSN 0031-9007
• Publisher: American Physical Society (APS)
• Country of Publication: United States
• Language: English

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