The DsTau Experiment: A Study for Tau-Neutrino Production

Mădălina Mihaela Miloi

doi:10.3390/particles3010013

Abstract

For clarifying the validity of the Lepton Universality hypothesis, one of the fundamental statements of the Standard Model, the interaction cross section for all three flavors of leptons have to be known with high precision. In neutrino sector, for electron and muon neutrinos, the interaction cross section is known fairly well, but for tau neutrino only poor estimations exist. In particular, the most direct measurement by the DONuT experiment was performed with rather poor accuracy due to low statistics and an uncertainty of the tau neutrino flux. The DsTau experiment proposes to study tau-neutrino production process and thus to improve significantly the accuracy of calculations of tau neutrino flux for neutrino accelerator experiments. To study reactions providing most of tau neutrinos, the experiment uses a setup based on high resolution nuclear emulsions, capable to register short lived particle decays created in proton-nucleus interactions. The present report is an overview of the DsTau experiment together with some of the preliminary results from the pilot run.

Highlights

The existence of tau-neutrino was predicted in 1975 after the discovery of tau lepton [1]
In 2000, tau-neutrino charged-current (CC) interactions were observed by the DONuT experiment [2]
There are 1000 Ds-tau events expected from 2.3 × proton interactions, from a total initial flux of 4.6 × protons in the DsTau experiment [5]

Summary

Introduction

The existence of tau-neutrino was predicted in 1975 after the discovery of tau lepton [1]. The first tau-neutrino interaction cross section measurement was performed with more than 50% systematic and 33% statistical uncertainties, due to the uncertainty in the tau-neutrino flux and the low statistics [3]. DsTau experiment proposes to study the tau-neutrino production and to improve the calculation of tau neutrino flux in the DONuT experiment to 10% level. With the help of DsTau results, in future neutrino experiments like SHiP [4], where 104 tau neutrinos interactions are expected, from about 5.7 × 1015 ντ and ντ to be produced by 2 × 1020 protons on target, both uncertainties in tau-neutrino interaction cross-section will be greatly reduced [5,6], making possible to the test of the Lepton Universality hypothesis. There are 1000 Ds-tau events expected from 2.3 × proton interactions, from a total initial flux of 4.6 × protons in the DsTau experiment [5]

Materials and Methods

Results

Conclusions and Outlook The