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Future detection of a supernova neutrino burst by large underground detectors would give important information for the explosion mechanism of collapse-driven supernovae. We studied the statistical analysis for the future detection of a nearby supernova by using a numerical supernova model and realistic Monte Carlo simulations of detection by the Super-Kamiokande detector. We mainly discuss the detectability of the signatures of the delayed explosion mechanism in the time evolution of the lumil6 e nosity and spectrum. For a supernova at 10 kpc away from the Earth, we Ðnd not only that the signature is clearly discernible but also that the deviation of the energy spectrum from the Fermi-Dirac (FD) distribution can be observed. The deviation from the FD distribution would, if observed, provide a test for the standard picture of neutrino emission from collapse-driven supernovae. For the D \ 50 kpc case, the signature of the delayed explosion is still observable, but statistical Ñuctuation is too large to detect the deviation from the FD distribution. We also propose a method for statistical reconstruction of the time evolution of luminosity and spectrum from data, by which we can get a smoother time evolution l6 e and smaller statistical errors than by a simple, time-binning analysis. This method is useful especially when the available number of events is relatively small, e.g., a supernova in the LMC or SMC. A neutronization burst of produces about Ðve scattering events when D \ 10 kpc, and this signal is diffil e Ïs cult to distinguish from events. l6 e p

Core-collapse supernovae are among the most energetic explosions in the universe marking the catastrophic end of massive stars. In spite of rigorous studies for several decades, we still don't understand the explosion mechanism completely. Since they are related to many astrophysical phenomena such as nucleosynthesis, gamma-ray bursts and acceleration of cosmic rays, understanding of their physics has been of wide interest to the astrophysical community.In this article, we review recent progress in the study of core-collapse supernovae focusing on the explosion mechanism, supernova neutrinos, and the gravitational waves. As for the explosion mechanism, we present a review paying particular attention to the roles of multidimensional aspects, such as convection, rotation, and magnetic fields, on the neutrino heating mechanism. Next, we discuss supernova neutrinos, which is a powerful tool to probe not only deep inside of the supernovae but also intrinsic properties of neutrinos. For this purpose, it is necessary to understand neutrino oscillation which has been established recently by a lot of experiments. Gravitational astronomy is now also becoming reality. We present an extensive review on the physical foundations and the emission mechanism of gravitational waves in detail, and discuss the possibility of their detections.

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By performing axisymmetric hydrodynamic simulations of core-collapse supernovae with spectral neutrino transport based on the isotropic diffusion source approximation scheme, we support the assumption that the neutrino-heating mechanism aided by the standing accretion shock instability (SASI) and convection can initiate an explosion of a 13$\ M_{\odot}$ star. Our results show that bipolar explosions are more likely to be associated with models that include rotation. We point out that models that form a north–south symmetric bipolar explosion can lead to larger explosion energies than the corresponding unipolar explosions can.