Joint Measurement of the ²³⁵U Antineutrino Spectrum by PROSPECT and STEREO

Journal Article · 21 February 2022 · Physical Review Letters

DOI: https://doi.org/10.1103/physrevlett.128.081802 · OSTI ID:1863085

Almazán, H.; Andriamirado, M. ; Balantekin, A.  B. ; Band, H.  R.; Bass, C.  D.; Bergeron, D.  E. ; Bernard, L.; Blanchet, A.; Bonhomme, A. ; Bowden, N.  S. ; Bryan, C.  D.; Buck, C. ; Classen, T.; Conant, A.  J. ; Deichert, G.; del Amo Sanchez, P. ; Delgado, A.; Diwan, M.  V.; Dolinski, M.  J.; El Atmani, I. ; Erickson, A.; Foust, B.  T. ; Gaison, J.  K.; Galindo-Uribarri, A. ; Gilbert, C.  E.; Hans, S.; Hansell, A.  B.; Heeger, K.  M. ; Heffron, B.; Jaffe, D.  E. ; Jayakumar, S.; Ji, X.; Jones, D.  C.; Koblanski, J.; Kyzylova, O.; Labit, L. ; Lamblin, J. ; Lane, C.  E.; Langford, T.  J. ; LaRosa, J.; Letourneau, A. ; Lhuillier, D. ; Licciardi, M.; Lindner, M.; Littlejohn, B.  R.; Lu, X.; Maricic, J.; Materna, T. ; Mendenhall, M.  P.; Meyer, A.  M.; Milincic, R.; Mueller, P.  E. ; Mumm, H.  P. ; Napolitano, J.; Neilson, R.; Nikkel, J.  A. ; Nour, S.; Palomino, J.  L.; Pessard, H. ; Pushin, D.  A.; Qian, X. ; Réal, J. -S. ; Ricol, J. -S. ; Roca, C.; Rogly, R. ; Rosero, R.; Salagnac, T.; Savu, V.; Schoppmann, S. ; Searles, M.; Sergeyeva, V.; Soldner, T. ; Stutz, A.; Surukuchi, P.  T.; Tyra, M.  A. ; Varner, R.  L.; Venegas-Vargas, D.; Vialat, M.; Weatherly, P.  B.; White, C.; Wilhelmi, J.; Woolverton, A.; Yeh, M.; Zhang, C.; Zhang, X.

The PROSPECT and STEREO collaborations present a combined measurement of the pure ²³⁵U antineutrino spectrum, without site specific corrections or detector-dependent effects. The spectral measurements of the two highest precision experiments at research reactors are found to be compatible with χ²/ndf = 24.1/21, allowing a joint unfolding of the prompt energy measurements into antineutrino energy. This $$\bar{ν}_e$$ energy spectrum is provided to the community, and an excess of events relative to the Huber model is found in the 5-6 MeV region. When a Gaussian bump is fitted to the excess, the data-model χ² value is improved, corresponding to a 2.4σ significance.

• Research Organization: Brookhaven National Laboratory (BNL), Upton, NY (United States); Lawrence Livermore National Laboratory (LLNL), Livermore, CA (United States); Oak Ridge National Laboratory (ORNL), Oak Ridge, TN (United States)
• Sponsoring Organization: USDOE National Nuclear Security Administration (NNSA); USDOE Office of Science (SC), High Energy Physics (HEP)
• Contributing Organization: PROSPECT and STEREO Collaborations
• Grant/Contract Number: AC05-00OR22725; AC52-07NA27344; SC0008347; SC0012704; SC0016060; SC0016357; SC0017660; SC0017815
• OSTI ID: 1863085
• Report Number(s): BNL-222919-2022-JAAM; LLNL-JRNL-826396
• Journal Information: Physical Review Letters, Journal Name: Physical Review Letters Journal Issue: 8 Vol. 128; ISSN 0031-9007
• Publisher: American Physical Society (APS)Copyright Statement
• Country of Publication: United States
• Language: English