Observables in neutrino mass spectroscopy using atoms

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

“…[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] …”

“…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:…”

“…[7,8,9], and it characterizes the level of coherence among atoms in the target. In a recent series of experiments [11] searching for paired superradiance, a twin process of RENP, the SPAN group has reported an induced coherence of about 6.5% using the method of adiabatic Raman scattering.…”

“…For simplicity, in our phenomenological study we assume η ω (t) = 100%, namely, a full coherence among all atoms. The spectrum function I(ω) of emitted photons carries valuable information of neutrino properties, and its analytical expression turns out to be [7,8,9] Dirac :…”

“…In a series of papers in the past few years [6,7,8], Yoshimura and his collaborators (also known as the SPAN group) have proposed to study a special atomic transition process |e → |g + |γ + |ν i + |ν j , where |e and |g are the excited and ground energy levels of atoms, |γ denotes the emitted photon, and the associated radiative emission of a neutrino pair (RENP) is indicated by |ν i +|ν j , with |ν i (for i = 1, 2, 3) being neutrino mass eigenstates. Since the energy difference between |e and |g is known to a very good accuracy, one can determine absolute neutrino masses through a precise measurement of the energy spectrum of the emitted photon.…”