Narrowing of the neutrino light curve in the OPERA experiment

TL;DR

The paper analyzes the neutrino light curve in the OPERA experiment, finding it narrower than the proton PDF and suggesting potential new physics or uncertainties in neutrino production, which impacts the significance of the original neutrino speed measurement.

Contribution

It introduces a two-parameter matched filtering method to compare neutrino and proton light curves, revealing a slight narrowing and implications for neutrino physics.

Findings

Neutrino light curve is narrower by about 0.4-0.5%

Reduced significance of OPERA neutrino detection to less than 4 sigma

Indicates possible new physics or uncertainties in neutrino creation

Abstract

In the OPERA experiment, the time of arrival of the neutrino light curve at LNGS is defined by a best-fit to the generating proton PDF at CERN. By a two parameter matched filtering procedure, we determine that the OPERA neutrino light curve is narrower by about 0.4-0.5% relative to the proton PDF. The results indicate as yet undetermined physics in the creation of neutrinos in CERN and a reduced significance of the OPERA detection to less than 4 $\sigma.$