학술논문
First Measurement of High-Energy Reactor Antineutrinos at Daya Bay
Document Type
article
Author
An, FP; Bai, WD; Balantekin, AB; Bishai, M; Blyth, S; Cao, GF; Cao, J; Chang, JF; Chang, Y; Chen, HS; Chen, HY; Chen, SM; Chen, Y; Chen, YX; Cheng, J; Cheng, ZK; Cherwinka, JJ; Chu, MC; Cummings, JP; Dalager, O; Deng, FS; Ding, YY; Diwan, MV; Dohnal, T; Dolzhikov, D; Dove, J; Dwyer, DA; Gallo, JP; Gonchar, M; Gong, GH; Gong, H; Gu, WQ; Guo, JY; Guo, L; Guo, XH; Guo, YH; Guo, Z; Hackenburg, RW; Hans, S; He, M; Heeger, KM; Heng, YK; Hor, YK; Hsiung, YB; Hu, BZ; Hu, JR; Hu, T; Hu, ZJ; Huang, HX; Huang, JH; Huang, XT; Huang, YB; Huber, P; Jaffe, DE; Jen, KL; Ji, XL; Ji, XP; Johnson, RA; Jones, D; Kang, L; Kettell, SH; Kohn, S; Kramer, M; Langford, TJ; Lee, J; Lee, JHC; Lei, RT; Leitner, R; Leung, JKC; Li, F; Li, HL; Li, JJ; Li, QJ; Li, RH; Li, S; Li, SC; Li, WD; Li, XN; Li, XQ; Li, YF; Li, ZB; Liang, H; Lin, CJ; Lin, GL; Lin, S; Ling, JJ; Link, JM; Littenberg, L; Littlejohn, BR; Liu, JC; Liu, JL; Liu, JX; Lu, C; Lu, HQ; Luk, KB; Z., B; B., X; Y., X; Q., Y; Mandujano, RC
Source
Physical Review Letters. 129(4)
Subject
Language
Abstract
This Letter reports the first measurement of high-energy reactor antineutrinos at Daya Bay, with nearly 9000 inverse beta decay candidates in the prompt energy region of 8-12 MeV observed over 1958 days of data collection. A multivariate analysis is used to separate 2500 signal events from background statistically. The hypothesis of no reactor antineutrinos with neutrino energy above 10 MeV is rejected with a significance of 6.2 standard deviations. A 29% antineutrino flux deficit in the prompt energy region of 8-11 MeV is observed compared to a recent model prediction. We provide the unfolded antineutrino spectrum above 7 MeV as a data-based reference for other experiments. This result provides the first direct observation of the production of antineutrinos from several high-Q_{β} isotopes in commercial reactors.