Probing Dark Energy via Neutrino and Supernova Observatories

Abstract

A novel method for extracting cosmological evolution parameters is proposed, using a probe other than light: future observations of the diffuse anti-neutrino flux emitted from core-collapse supernovae (SNe), combined with the SN rate extracted from future SN surveys. The relic SN neutrino differential flux can be extracted by using future neutrino detectors such as Gadoliniumenriched, megaton, water detectors or 100-kiloton detectors of liquid Argon or liquid scintillator.The core-collapse SN rate can be reconstructed from direct observation of SN explosions using future precision observatories. Our method, by itself, cannot compete with the accuracy of the optical-based measurements but may serve as an important consistency check as well as a source of complementary information. The proposal does not require construction of a dedicated experiment, but rather relies on future experiments proposed for other purposes.

Probing late neutrino mass properties with supernova neutrinos

“…We expect that the future generation water Cerenkov detectors enriched with gadolinium such as UNO, HyperKamiokande, or MEMPHYS would be able to detect a substantial number of SRN antineutrino events in a year [15]. Note that the threshold for this is on the order of 10 MeV and depends on the location of the detector, especially due to reactor backgrounds [13,14]. The effects of smearing due to the energy resolution of the water cerenkov-type detector needs to also be taken into account in a detailed analysis.…”

“…This lower bound on the coupling is represented by the diagonal blue (solid) line. If the resonance energy is below 12 MeV then there is a large background from nuclear reactor antineutrinos [13,14]. To have a significant signal we take M G to be above 2m ν E then the signal would be above the reactor background.…”

“…This depletion is present up to the location of the dip, which in this case is 16 MeV. The main source of background, assuming the addition of Gd to the water Cerenkov detector, are nuclear reactor electron antineutrinos, but this background is small above neutrino energies of about 12 MeV [13,14]. This background is dependent on the location of the experiment and could be nearly absent.…”

“…In addition, detection of this signal would also be direct evidence of the presence of the cosmic background neutrinos. Hundreds of events per year from the flux of the SRN antineutrinos could be seen at next-generation large megaton water Cerenkov detectors [13,14] such as UNO, Hyper-Kamiokande or MEMPHYS if they are enriched with Gadolinium [15], or from the flux of the SRN neutrinos in a large 100 kton liquid argon neutrino detector [16].…”

“…This background is dependent on the location of the experiment and could be nearly absent. Clearly the detector which is not near nuclear reactors would have a better chance of seeing the signal for lower values of the resonance energy [13,14].…”