Final Search for Short-Baseline Neutrino Oscillations with the PROSPECT-I Detector at HFIR

Journal Article · Mon Apr 14 00:00:00 UTC 2025 · Physical Review Letters

DOI: https://doi.org/10.1103/PhysRevLett.134.151802 · OSTI ID:2556903

Andriamirado, M.  ^[1]; Balantekin, A. B.  ^[2]; Bass, C. D.  ^[3]; Benevides Rodrigues, O.  ^[1]; Bernard, E. P.  ^[4]; Bowden, N. S.  ^[4]; Bryan, C. D.  ^[5]; Carr, R.  ^[6]; Classen, T.  ^[4]; Conant, A. J.  ^[5]; Deichert, G. ^[5]; Dolinski, M. J.  ^[7]; Erickson, A.  ^[8]; Galindo-Uribarri, A.  ^[9]; Gokhale, S. ^[10]; Grant, C.  ^[11]; Hans, S. ^[10]; Hansell, A. B.  ^[12]; Heeger, K. M.  ^[13]; Heffron, B.  ^[9] ; Jaffe, D. E.  ^[10]; Jayakumar, S.  ^[7]; Koblanski, J. ^[14]; Kunkle, P. ^[11]; Lane, C. E.  ^[7]; Littlejohn, B. R.  ^[1]; Lozano Sanchez, A. ^[7]; Lu, X.  ^[9]; Machado, F.  ^[1]; Maricic, J.  ^[14]; Mendenhall, M. P.  ^[4]; Meyer, A. M. ^[14]; Milincic, R. ^[14]; Mueller, P. E.  ^[5]; Mumm, H. P.  ^[15]; Neilson, R.  ^[7]; Qian, X.  ^[10]; Roca, C.  ^[4]; Rosero, R. ^[10]; Surukuchi, P. T.  ^[13]; Sutanto, F.  ^[4]; Venegas-Vargas, D.  ^[9]; Weatherly, P. B.  ^[7]; Wilhelmi, J. ^[13]; Yeh, M.  ^[10]; Zhang, C.  ^[10]; Zhang, X.  ^[4]

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1. Illinois Institute of Technology
2. University of Wisconsin
3. Le Moyne College
4. Lawrence Livermore National Laboratory
5. Oak Ridge National Laboratory
6. United States Naval Academy
7. Drexel University
8. Georgia Institute of Technology
9. Oak Ridge National Laboratory; University of Tennessee
10. Brookhaven National Laboratory
11. Boston University
12. Susquehanna University
13. Yale University
14. University of Hawaii
15. National Institute of Standards and Technology

The PROSPECT experiment is designed to perform precise searches for antineutrino disappearance at short distances (7–9 m) from compact nuclear reactor cores. This Letter reports results from a new neutrino oscillation analysis performed using the complete data sample from the PROSPECT-I detector operated at the High Flux Isotope Reactor in 2018. The analysis uses a multiperiod selection of inverse beta decay neutrino interactions with reduced backgrounds and enhanced statistical power to set limits on electron neutrino disappearance caused by mixing with sterile neutrinos with 0.2–20 eV² mass splittings. Inverse beta decay positron energy spectra from six different reactor-detector distance ranges are found to be statistically consistent with one another, as would be expected in the absence of sterile neutrino oscillations. The data excludes at 95% confidence level the existence of sterile neutrinos in regions above 3 eV² previously unexplored by terrestrial experiments, including all space below 10 eV² suggested by the recently strengthened Gallium Anomaly. The best-fit point of the Neutrino-4 reactor experiment’s claimed observation of short-baseline oscillation is ruled out at more than 5 standard deviations.

• Research Organization: Brookhaven National Laboratory (BNL), Upton, NY (United States); Illinois Institute of Technology, Chicago, IL (United States); Lawrence Livermore National Laboratory (LLNL), Livermore, CA (United States); Univ. of Hawaii, Honolulu, HI (United States)
• Sponsoring Organization: Heising-Simons Foundation; USDOE National Nuclear Security Administration (NNSA); USDOE Office of Science (SC), High Energy Physics (HEP)
• Contributing Organization: PROSPECT Collaboration
• Grant/Contract Number: AC05-00OR22725; AC52-07NA27344; SC0008347; SC0010504; SC0012704; SC0016357; SC0017660; SC0017815
• OSTI ID: 2556903
• Report Number(s): BNL--228038-2025-JAAM; LLNL--JRNL-865584
• Journal Information: Physical Review Letters, Journal Name: Physical Review Letters Journal Issue: 15 Vol. 134; ISSN 0031-9007; ISSN 1079-7114
• Publisher: American Physical Society (APS)Copyright Statement
• Country of Publication: United States
• Language: English