A first measurement of the interaction cross section of the tau neutrino

Abstract

The DONuT experiment collected data in 1997 and published first results in 2000 based on four observed ${\nu }_{\tau }$ charged-current (CC) interactions. The final analysis of the data collected in the experiment is presented in this paper, based on $3.6\times 10^{17}$ protons on target using the 800 GeV Tevatron beam at Fermilab. The number of observed ${\nu }_{\tau }$ CC interactions is 9, from a total of 578 observed neutrino interactions. We calculated the energy-independent part of the tau-neutrino CC cross section ($\nu +\bar{\nu }$), relative to the well-known ${\nu }_e$ and ${\nu }_{\mu }$ cross sections. The ratio $\sigma ({\nu }_{\tau })$/$\sigma ({\nu }_{e,\mu })$ was found to be $1.37\pm 0.35\pm 0.77$. The ${\nu }_{\tau }$ CC cross section was found to be $0.72\pm 0.24\pm 0.36\times 10^{-38}$ cm${}^2{\mathrm{GeV}}^{-1}$. Both results are in agreement the Standard Model.

37 pages, 15 figures