SN 1987A Neutrino Research Articles

Updated limits on the electron neutrino mass and large angle oscillations from SN1987A

We supplement Maximum Likelihood methods with a Monte-Carlo simulation to re-investigate the SN1987A neutrino burst detection by the IMB and Kamiokande experiments. The detector simulations include background in the the latter and “dead-time” in the former. We consider simple neutrinosphere cooling models, explored previously in the literature, to explore the case for or against neutrino vacuum mixing and massive neutrinos. In the former case, involving kinematically irrelevant masses, we find that the full range of vacuum mixing angles, 0 ≤ sin 2 2 θv ≤ 1, is permitted, and the Maximum Likelihood mixing angle is sin 2 2 θv = 0.45. In the latter case we find that the inclusion of “dead-time” reduces previous m ν e upper bounds by 10%, and supplementing the Maximum Likelihood analysis with a Monte-Carlo goodness-of-fit test results in a further 15% reduction in the m ν e upper limit. Our 95% C.L. upper limit for m ν e is 19.6 eV, while the best fit value is ∼ 0 eV.

Supernova neutrinos as probes of long-range non-gravitational interactions of dark matter

We use the SN1987A neutrino events to set relevant limits on possible non-gravitational long-range forces of dark matter.

Neutrino oscillations from beam dump experiments and neutrino events from SN 1987A

The neutrino mass and mixing from CERN beam dump experiments carried out in 1979 and 1982 are used to examine energy and timing of Kamiokande II and IMB SN 1987A neutrino events. Some specific features are well explained. The mass and mixing also increase the hope for positive results from neutrinoless double-beta-decay search experiments.

Interpretation of the kinematical properties of SN 1987A neutrino data by an admixture of nu micro, nu micro-bar and nu tau, nu tau -bar.

Statistical tests suitable for small data samples are used to compare the observed energies and angles of the SN 1987A neutrino events with distributions expected for a range of assumed temperatures and relative luminosities of different neutrino species. The highest confidence levels are obtained for simulated samples with an admixture of ${\ensuremath{\nu}}_{\ensuremath{\mu}}$, ${\overline{\ensuremath{\nu}}}_{\ensuremath{\mu}}$ and ${\ensuremath{\nu}}_{\ensuremath{\tau}}$, ${\overline{\ensuremath{\nu}}}_{\ensuremath{\tau}}$ added to the ${\overline{\ensuremath{\nu}}}_{e}$ interactions. This is a consequence of relatively high-energy thresholds [particularly for the Irvine-Michigan-Brookhaven (IMB) detector] and ${\ensuremath{\nu}}_{\ensuremath{\mu}}$, ${\overline{\ensuremath{\nu}}}_{\ensuremath{\mu}}$, ${\ensuremath{\nu}}_{\ensuremath{\tau}}$, ${\overline{\ensuremath{\nu}}}_{\ensuremath{\tau}}$ energies being greater than those of ${\overline{\ensuremath{\nu}}}_{e}$. It is also found that a ${\ensuremath{\nu}}_{\ensuremath{\mu}}$, ${\overline{\ensuremath{\nu}}}_{\ensuremath{\mu}}$, ${\ensuremath{\nu}}_{\ensuremath{\tau}}$, ${\overline{\ensuremath{\nu}}}_{\ensuremath{\tau}}$ admixture is more probable than a ${\ensuremath{\nu}}_{e}$ contribution for which the IMB detector is especially inefficient. A possibility of identifying ${\ensuremath{\nu}}_{\ensuremath{\mu}}$, ${\overline{\ensuremath{\nu}}}_{\ensuremath{\mu}}$ and ${\ensuremath{\nu}}_{\ensuremath{\tau}}$, ${\overline{\ensuremath{\nu}}}_{\ensuremath{\tau}}$ interactions from a future supernova collapse is also discussed.

Pair production of helicity-flipped neutrinos in supernovae.

The emissivity was calculated for the pair production of helicity-flipped neutrinos, in a way that can be used in supernova calculations. Also presented are simple estimates which show that such process can act as an efficient energy-loss mechanism in the shocked supernova core, and this fact is used to extract neutrino mass limits from SN 1987A neutrino observations.

Constraints on SN 1987A neutrino types from the Homestake Mine detectors

view Abstract Citations (2) References (7) Co-Reads Similar Papers Volume Content Graphics Metrics Export Citation NASA/ADS Constraints on SN 1987A Neutrino Types from the Homestake Mine Detectors Fireman, E. L. Abstract Data obtained with the Homestake Mine chlorine solar neutrino detector constrain the vmu_'s and vtau_'s as well as the v_e_'s in the supernova SN 1987A neutrino burst. The proton production in this detector by the vmu_ and vtau_, neutrino types is calculated and the ^37^Ar production by the protons is obtained. The sensitivities of the Homestake Mine chlorine detector for the v_e_, vmu_, and vtau_, neutrinos from SN 1987A are higher than those of the Kamiokande II detector only for v_e_'s of energy less than 15 Mev and for large vmu_ and vtau_ masses. Publication: The Astrophysical Journal Pub Date: January 1990 DOI: 10.1086/168309 Bibcode: 1990ApJ...349..241F Keywords: Neutrinos; Nuclear Astrophysics; Supernova 1987a; Argon Isotopes; Protons; Radiation Detectors; Space Radiation; NEUTRINOS; STARS: INDIVIDUAL ALPHANUMERIC: SN 1987A; STARS: SUPERNOVAE full text sources ADS | data products NED (2) SIMBAD (1)

Evidence for strange matter in supernovae?

With the aim of overcoming the present energetic difficulties in getting type-II supernovae explosions, we present a possible scenario based on strange-matter formation. The observational expectations of this picture are discussed and the predictions of the model for SN 1987A neutrinos and remnant pulsar are examined.

Torsion Effects on Neutrino Emission from Dense Collapsing Cores

AbstractWe consider the effects of torsion on the emission of neutrinos in a hot dense neutron medium and we explore the consequences for the case of SN1987A neutrinos.

Implications of the supernova SN1987A neutrino signals.

The neutrino events from the supernova SN1987A observed by the Kamiokande II and Irvine-Michigan-Brookhaven detectors are used to suggest constraints on neutrino physics. In particular, bounds on the value of the electron neutrino magnetic moment ${\mathrm{\ensuremath{\mu}}}_{\mathit{v}\mathit{e}}$\ensuremath{\lesssim}(${10}^{\mathrm{\ensuremath{-}}12}$-${10}^{\mathrm{\ensuremath{-}}13}$)${\mathrm{\ensuremath{\mu}}}_{\mathrm{B}}$ are suggested.

The neutrino radiation of collapsing stellar cores and the neutrino burst detected from SN 1987 A

The properties of the neutrino burst generated by massive 1.5–2M⊙ collapsing stellar iron-oxygen cores are discussed. Special attention is given to the neutrino heat conductivity theory which allows us to calculate the transport of neutrinos through the collapsing stellar core up to the formation and during the first seconds of cooling of a hot hydrostatic neutron star. The theoretical predictions seem to be in good agreement with both the KAMIOKANDE II and IMB data on the neutrino burst detected from SN 1987A. The most reliable constraint on the neutrino rest mass is shown to bemv<20–30eV, while the safest upper limit on the neutrino magnetic moment, µv < 10−11 Bohr magnetons, results rather from the cooling of white dwarfs than from the SN 1987A neutrino data.