Precision measurement of the speed of propagation of neutrinos using the MINOS detectors

TL;DR

This paper reports a precise measurement of neutrino speed over 734 km, confirming it is consistent with the speed of light within experimental uncertainties, using the MINOS detectors at Fermilab.

Contribution

First two-detector measurement of neutrino propagation speed over a long baseline, providing high-precision confirmation of relativistic neutrino speeds.

Findings

Neutrino speed difference from light is within 1.1×10^{-6}

Results are consistent with neutrinos traveling at light speed

Measurement confirms relativistic neutrino behavior

Abstract

We report a two-detector measurement of the propagation speed of neutrinos over a baseline of 734 km. The measurement was made with the NuMI beam at Fermilab between the near and far MINOS detectors. The fractional difference between the neutrino speed and the speed of light is determined to be $(v/c-1) = (1.0 \pm 1.1) \times 10^{-6}$, consistent with relativistic neutrinos.