The PROSPECT Physics Program

TL;DR

PROSPECT is a two-phase experiment using segmented liquid scintillator detectors to precisely measure reactor antineutrino spectra and search for sterile neutrinos, aiming to clarify spectral anomalies and test sterile neutrino hypotheses.

Contribution

It introduces a novel segmented detector setup for high-precision antineutrino measurements and sterile neutrino searches at short baselines.

Findings

Probes sterile neutrino parameter space below 10 eV^2 at 5σ in 6 years

Detects spectral deviations and tests sterile neutrino hypotheses

Achieves 4σ sensitivity to ν_e disappearance in 1 year

Abstract

The Precision Reactor Oscillation and Spectrum Experiment, PROSPECT, is designed to make a precise measurement of the antineutrino spectrum from a highly-enriched uranium reactor and probe eV-scale sterile neutrinos by searching for neutrino oscillations over meter-long distances. PROSPECT is conceived as a 2-phase experiment utilizing segmented $^6$Li-doped liquid scintillator detectors for both efficient detection of reactor antineutrinos through the inverse beta decay reaction and excellent background discrimination. PROSPECT Phase I consists of a movable 3-ton antineutrino detector at distances of 7 - 12 m from the reactor core. It will probe the best-fit point of the $\nu_e$ disappearance experiments at 4$\sigma$ in 1 year and the favored region of the sterile neutrino parameter space at $>$3$\sigma$ in 3 years. With a second antineutrino detector at 15 - 19 m from the reactor, Phase II of PROSPECT can probe the entire allowed parameter space below 10 eV$^{2}$ at 5$\sigma$ in 3 additional years. The measurement of the reactor antineutrino spectrum and the search for short-baseline oscillations with PROSPECT will test the origin of the spectral deviations observed in recent $\theta_{13}$ experiments, search for sterile neutrinos, and conclusively address the hypothesis of sterile neutrinos as an explanation of the reactor anomaly.