A combined analysis of short-baseline neutrino experiments in the (3+1) and (3+2) sterile neutrino oscillation hypotheses

Preprint
Publisher Website
Google Scholar
Abstract
We investigate adding two sterile neutrinos to resolve the apparent tension existing between short-baseline neutrino oscillation results and CPT-conserving, four-neutrino oscillation models. For both (3+1) and (3+2) models, the level of statistical compatibility between the combined data set from the null short-baseline experiments Bugey, CHOOZ, CCFR84, CDHS, and KARMEN, on one hand, and the LSND data set on the other hand, is computed. A combined analysis of all six short-baseline experiments, including LSND, is also performed, to obtain the favored regions in neutrino mass and mixing parameter space for both models. Finally, three statistical tests to compare the (3+1) and the (3+2) hypotheses are discussed. All tests show that (3+2) models fit the existing short-baseline data significantly better than (3+1) models. In particular, we estimate that the null sets and LSND are compatible at the 93% and 55% combined confidence level, for (3+1) and (3+2) models, respectively.

This publication has 0 references indexed in Scilit: