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We consider the situation where the luminosity from a transient event is reprocessed by an optically thick wind. Potential applications are the tidal disruption of stars by black holes, engine-powered supernovae, and unique fast transients found by current and future wide-field surveys. We derive relations between the injected and observed luminosity for steady and time dependent winds, and discuss how the temperature is set for scattering-dominated radiative transport. We apply this framework to specific examples of tidal disruption events and the formation of a black hole by a massive star, as well as discuss other applications such as deriving observables from detailed hydrodynamic simulations. We conclude by exploring what is inferred about the mass loss rate and underlying engine powering AT2018cow if it is explained as a wind-reprocessed transient, demonstrating that its optical emission is consistent with reprocessing of the observed soft X-rays.
Four years into the mission, the understanding of the performance of the Fermi Large Area Telescope (LAT) and data analysis have increased enormously since launch. Thanks to a careful analysis of flight data, we were able to trace back some of the mo
We present an ongoing, systematic search for extragalactic infrared transients, dubbed SPIRITS --- SPitzer InfraRed Intensive Transients Survey. In the first year, using Spitzer/IRAC, we searched 190 nearby galaxies with cadence baselines of one mont
I present a brief up-to-date review of the current understanding of Supergiant Fast X-ray Transients, with an emphasis on the observational point of view. After more than a decade since their discovery, a remarkable progress has been made in getting
A fraction of high-mass X-ray binaries are supergiant fast X-ray transients. These systems have on average low X-ray luminosities, but display short flares during which their X-ray luminosity rises by a few orders of magnitude. The leading model for
We present the longest-term timing study so far of three Rotating Radio Transients (RRATs) - J1819-1458, J1840-1419 and J1913+1330 - performed using the Lovell, Parkes and Green Bank telescopes over the past decade. We study long-term and short- term