Testing decay of astrophysical neutrinos with incomplete information

Abstract

Neutrinos mix and have mass differences, so decays from one to another must occur. But how fast? The best direct limits on non-radiative decays, based on solar and atmospheric neutrinos, are weak, τ 10 −3 s (m/eV) or much worse. Greatly improved sensitivity, τ ∼ 10 3 s (m/eV), will eventually be obtained using neutrinos from distant astrophysical sources, but large uncertaintiesin neutrino properties, source properties, and detection aspects -do not allow this yet. However, there is a way forward now. We show that IceCube diffuse neutrino measurements, supplemented by improvements expected in the near term, can increase sensitivity to τ ∼ 10 s (m/eV) for all neutrino mass eigenstates. We provide a roadmap for the necessary analyses and show how to manage the many uncertainties. If limits are set, this would definitively rule out the long-considered possibility that neutrino decay affects solar, atmospheric, or terrestrial neutrino experiments.

A study of invisible neutrino decay at DUNE and its effects on θ23 measurement

“…A recent study performed in ref. [42] states that the IceCube experiment can reach a sensitivity of τ /m ≥ 10 s/eV for both hierarchies for 100 TeV neutrinos coming from a source at a distance of 1 Gpc.…”

Exploring a nonminimal sterile neutrino model involving decay at IceCube

“…Neutrino decay is predicted by the SM, but the rate is too small to be detected by present experimental searches. Neutrino decay via some new physics process may be important and has previously been considered in the context of solar neutrinos [51][52][53][54][55][56], atmospheric neutrinos [57][58][59][60][61][62], accelerator neutrinos [60,[63][64][65], supernova neutrinos [66][67][68][69], cosmology [70,71], and high-energy astrophysical neutrinos [72][73][74]. Although neutrino decay is an interesting theoretical proposition, it has not been observed and is very constrained for active neutrinos [52,71,75,76].…”

W -boson and trident production in TeV–PeV neutrino observatories

“…Shower events are especially important because of the ability to faithfully reconstruct the neutrino spectrum. The shower spectrum can be estimated as [8,41,90]…”

“…By comparing the observed spectra of events that have traveled through Earth or not, the cross section can be measured at energies far above the reach of laboratory experiments [24][25][26][27][28][29]. And many models of new physics have been powerfully limited by the IceCube data [30][31][32][33][34][35][36][37][38][39][40][41][42][43].…”