Bound-State Beta Decay of $\mathbf{\mathrm{^{205}{Tl}^{81+}}}$ Ions and the LOREX Project
Abstract
Stable Tl ions have the lowest known energy threshold for capturing electron neutrinos () of \,keV. The Lorandite Experiment (LOREX), proposed in the 1980s, aims at obtaining the longtime averaged solar neutrino flux by utilizing natural deposits of Tl-bearing lorandite ores. To determine the capture cross section, it is required to know the strength of the weak transition connecting the ground state of Tl and the 2.3 keV first excited state in Pb. The only way to experimentally address this transition is to measure the bound-state beta decay () of fully ionized ions. After three decades of meticulous preparation, the half-life of the decay of has been measured to be days using the Experimental Storage Ring (ESR) at GSI, Darmstadt. The longer measured half-life compared to theoretical estimates reduces the expected signal-to-noise ratio in the LOREX, thus challenging its feasibility.
Keywords
Cite
@article{arxiv.2501.06029,
title = {Bound-State Beta Decay of $\mathbf{\mathrm{^{205}{Tl}^{81+}}}$ Ions and the LOREX Project},
author = {R. S. Sidhu and G. Leckenby and R. J. Chen and R. Mancino and Yu. A. Litvinov and G. Martínez-Pinedo and G. Amthauer and M. Bai and K. Blaum and B. Boev and F. Bosch and C. Brandau and V. Cvetković and T. Dickel and I. Dillmann and D. Dmytriiev and T. Faestermann and O. Forstner and B. Franczak and H. Geissel and R. Gernhäuser and J. Glorius and C. Griffin and A. Gumberidze and E. Haettner and P. -M. Hillenbrand and P. Kienle and W. Korten and Ch. Kozhuharov and N. Kuzminchuk and K. Langanke and S. Litvinov and E. Menz and T. Morgenroth and T. Neff and C. Nociforo and F. Nolden and M. K. Pavícević and N. Petridis and U. Popp and S. Purushothaman and R. Reifarth and M. S. Sanjari and C. Scheidenberger and U. Spillmann and M. Steck and Th. Stöhlker and Y. K. Tanaka and M. Trassinelli and S. Trotsenko and L. Varga and M. Wang and H. Weick and P. J. Woods and T. Yamaguchi and Y. H. Zhang and J. Zhao and K. Zuber},
journal= {arXiv preprint arXiv:2501.06029},
year = {2025}
}