Abstract
We study the effect of exotic charged current interactions on the electron energy spectrum in tritium decay, focussing on the KATRIN experiment and a possible modified setup that has access to the full spectrum. Both sub-eV and keV neutrino masses are considered. We perform a fully relativistic calculation and take all possible new interactions into account, demonstrating the possible sizable distortions in the energy spectrum.
Highlights
Provides an excellent opportunity to look for spectral distortions, which are characteristic for new mass states and for exotic interactions
Our analysis reaches beyond existing literature in the following points: (i) In our generic relativistic calculation we find that regardless of the interaction the energy spectrum can be parameterized by six functions which depend only on the involved particle masses and coupling constants, and whose precise form is specified by the interaction; (ii) we use an effective operator approach to study all possible Lorentz-invariant charged current interactions [3, 24] including right-handed sterile neutrinos; (iii) both small neutrino masses of order 0.5 eV and large masses of order keV are considered, and the significance of accessing the full electron energy spectrum is stressed
This allows in principle to improve the bounds on the effective operators and adds additional physics motivation to modifications of high activity neutrino mass experiments to study the full spectrum
Summary
We consider the β-decay of a mother nucleus A to a daughter nucleus B, an electron e− and an electron antineutrino νe:. The final electron antineutrino state |νe is a superposition of mass eigenstates |νj. We will assume that apart from the three active neutrinos additional, necessarily sterile, neutrino species are present, i.e. where ns is the number of sterile neutrinos and U denotes the (3 + ns) × (3 + ns) lepton mixing matrix. We will work out general expressions for the electron energy spectrum, assuming only that the process in equation (2.1) is generated by an interaction that is mediated by particles much heavier than the nuclear scale. We make no assumption about the Lorentz structure of the interactions
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
