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We investigate the potential of the upcoming LOBSTER space observatory (due circa 2009) to detect soft X-ray flashes from shock breakout in supernovae, primarily from Type II events. LOBSTER should discover many SN breakout flashes, although the number is sensitive to the uncertain distribution of extragalactic gas columns. X-ray data will constrain the radii of their progenitor stars far more tightly than can be accomplished with optical observations of the SN light curve. We anticipate the appearance of blue supergiant explosions (SN 1987A analogs), which will uncover a population of these underluminous events. We consider also how the mass, explosion energy, and absorbing column can be constrained from X-ray observables alone and with the assistance of optically-determined distances. These conclusions are drawn using known scaling relations to extrapolate, from previous numerical calculations, the LOBSTER response to explosions with a broad range of parameters. We comment on a small population of flashes with 0.2 < z < 0.8 that should exist as transient background events in XMM, Chandra, and ROSAT integrations.
The mode of explosive burning in Type Ia SNe remains an outstanding problem. It is generally thought to begin as a subsonic deflagration, but this may transition into a supersonic detonation (the DDT). We argue that this transition leads to a breakou
Massive stars undergo a violent death when the supply of nuclear fuel in their cores is exhausted, resulting in a catastrophic core-collapse supernova. Such events are usually only detected at least a few days after the star has exploded. Observation
Neutrinos and gravitational waves are the only direct probes of the inner dynamics of a stellar core collapse. They are also the first signals to arrive from a supernova and, if detected, establish the moment when the shock wave is formed that unbind
Shock breakout is the brightest radiative phenomenon in a Type II supernova (SN). Although it was predicted to be bright, the direct observation is difficult due to the short duration and X-ray/ultraviolet-peaked spectra. First entire observations of
High cadence ultraviolet, optical and near-infrared photometric and low-resolution spectroscopic observations of the peculiar Type II supernova (SN) 2018hna are presented. The early phase multiband light curves exhibit the adiabatic cooling envelope