Identifying the neutrino mass spectrum from a supernova neutrino burst

Abstract

We study the role that the future detection of the neutrino burst from a galactic supernova can play in the reconstruction of the neutrino mass spectrum. We consider all possible 3ν mass and flavor spectra which describe the solar and atmospheric neutrino data. For each of these spectra we find the observable effects of the supernova neutrino conversions both in the matter of the star and the earth. We show that studies of the electron neutrino and anineutrino spectra as well as observations of the neutral current effects from supernova will allow us (i) to identify the solar neutrino solution, (ii) to determine the type of mass hierarchy (normal or inverted) and (iii) to probe the mixing |U e3 | 2 to values as low as 10 −4 − 10 −3 .

A comprehensive study of neutrino spin-flavour conversion in supernovae and the neutrino mass hierarchy

“…For the pure MSW effect, it is well-known that the supernova neutrino signal with the case of inverted hierarchy would be very different from that with normal hierarchy [2,3]. From the analogy of the conversion mechanisms between the MSW and RSF effects, it is easily inferred that the RSF conversions will be also very sensitive to the mass hierarchy.…”

“…What we can learn from the next galactic supernova has been considered in many articles (for a review, see [1]). For example, we can constrain the properties of neutrino oscillations, such as the mixing angle between the first and third mass eigenstates (θ 13 ), and the mass hierarchy [normal (m 1 ≪ m 3 ) or inverted (m 1 ≫ m 3 )] [2,3].…”

Determining neutrino and supernova parameters with a galactic supernova

“…Clearly, supernova neutrinos provide an excellent chance to determine two of the neutrino unknowns: the mass hierarchy and θ 13 . This fact has been pointed out and explored by several authors [14,15,16].…”

“…When calculating the oscillation probabilities we have neglected the Earth matter effects [14]. These effects can be precisely calculated and thus will not affect our conclusions much, if the direction of the supernova is known.…”

“…Bounds on neutrino masses, from the delayed time-of-flight as a function of the neutrino energy, obtainable with future large water Cherenkov as well as with a liquid scintillation experiment has also been discussed [21]. Other methods to extract information from a SN are: analyzing the earth matter effects [14,22,23,24,25,26] which may occur if the supernova neutrinos traverse the Earth (mantle/core) before reaching the detector; studying the variation of particularly constructed variables [15,27,28], such as ratios of average energies, and recently the possibility of observing shock wave effects has attracted attention [15,29,30,31,32].…”