Conditions for statistical determination of the neutrino mass spectrum in radiative emission of neutrino pairs in atoms

Abstract

The photon spectrum in macrocoherent atomic de-excitation via radiative emission of neutrino pairs (RENP) has been proposed as a sensitive probe of the neutrino mass spectrum, capable of competing with conventional neutrino experiments. In this paper we revisit this interesting proposal in order to quantify the requirements for statistical determination of some of the properties of the neutrino spectrum, in particular the neutrino mass scale and the mass ordering. Our results are shown as the product of the experimental lifetime, the target volume, and the number density of atoms which have to be set in a coherence state with a given electric field in the target, needed for determination of these properties with a given CL.

Improved statistical determination of absolute neutrino masses via radiative emission of neutrino pairs from atoms

“…It has been found that even under ideal conditions, such as a perfect coherence among target atoms and an excellent detection efficiency, determining neutrino masses with a good precision requires a detection time on the order of a few days to months, which seems to be beyond the reach of current technologies. For instance, it has been shown that a few months are needed for a 3σ determination of m 0 ∼ 0.01 eV with an accuracy better than 10% [9]. In this paper, we improve the previous work by a detailed analysis of the photon spectrum, and demonstrate that one can reduce the detection time by one order of magnitude by looking into the second kink in the fine structure.…”

“…[7,8,9], where the details of derivation can be found. Defining the RENP rate as the number of emitted photons of a frequency ω per unit time, we obtain [7,8,9] …”

“…[9], V is the target volume, n is the number density of atoms in the target, and γ vg is the spontaneous dipole transition rate between states |v and |g . Lastly, I(ω) and η ω (t) are the photon energy spectrum function and the medium dynamical factor, respectively.…”

“…As an example, in this work we focus on the atomic candidate Yb, whose relevant energy levels and atomic parameters have been identified in Refs. [7,8,9] and are now summarized as follows:…”

“…Recently, a statistical analysis of the photon spectrum from the RENP process has been carried out in Ref. [9], where the experimental requirements for a statistical determination of neutrino mass scale are quantitatively investigated. It has been found that even under ideal conditions, such as a perfect coherence among target atoms and an excellent detection efficiency, determining neutrino masses with a good precision requires a detection time on the order of a few days to months, which seems to be beyond the reach of current technologies.…”