Neutrino mass spectroscopy using Er${}^{3+}$ ions placed at inversion center of host crystals

Abstract

We propose neutrino mass spectroscopy using Er${}^{3+}$:Cs${}_2$NaYF${}_6$ or :Y${}_2$O${}_3$ crystal placed in hollow of a Bragg fiber as a target system. Unknown neutrino parameters and properties such as the lightest neutrino mass, Majorana/Dirac distinction, and CP violating phases can be explored by measuring scattered photons (${\hat{I}}^3$) along the excitation (and fiber) axis by varying Raman trigger (${\hat{I}}_0^3$) directions, in Er${}^{3+}$ de-excitation process from $|e⟩$ state to $|g⟩$ state; $|e⟩,|e⟩+{\hat{I}}_0^3\to |g⟩+{\hat{I}}^3+\hat{I}{½}_i\bar{\hat{I}}{½}_j$, $\hat{I}{½}_i,i=1,2,3$ being a mass-resolved neutrino state. Rates and required level of QED background rejection are calculated using measured data of the target system.

12 pages, 8 figures