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

Published

February 22, 2022

Author(s)

Hans Pieter Mumm, Denis E. Bergeron, Mark Tyra, Jerome LaRosa, Svetlana Nour, PROSPECT collaboration, STEREO collaboration

Abstract

The PROSPECT and STEREO collaborations present a combined measurement of the pure 235U antineutrino spectrum, with site specific corrections and effects dependent on the separate detectors removed. 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 antineutrino energy spectrum is provided to the community, and an excess of events is found in the 5-6 MeV region. When a gaussian bump is fitted to the excess, the data-model χ2 value is reduced by 12.0 while removing 3 degrees of freedom, corresponding to a 2.4σ significance.

Citation

Physical Review Letters

Volume

128

Issue

8

Pub Type

Journals

Download Paper

https://doi.org/10.1103/PhysRevLett.128.081802

Local Download

Keywords

reactor antineutrino spectrum, 235U neutrino spectrum, fission daughter neutrinos

Citation

Mumm, H. , Bergeron, D. , Tyra, M. , LaRosa, J. , Nour, S. , COLLABORATION, P. and collaboration, S. (2022), Joint Measurement of the 235U Antineutrino Spectrum with PROSPECT and STEREO, Physical Review Letters, [online], https://doi.org/10.1103/PhysRevLett.128.081802, https://tsapps.nist.gov/publication/get_pdf.cfm?pub_id=932829 (Accessed October 23, 2025)