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Stripped-envelope supernovae (SE SNe) were considered as the explosions of single massive stars with strong stellar winds, while later observations favor binary origins. One direct evidence to support the binary origins is to find the surviving companions of SE SNe since previous numerical studies suggested that the binary companion should survive the supernova impact and could be detectable. Recently, Gagliano et al. (2022) reported that the nearby Type Ic SN 2020oi in M100 (~17.1 Mpc) resulted from a binary system based on the HST photometric and spectroscopic observation. Based on the suggested binary properties of SN 2020oi, we conduct two-dimensional hydrodynamics simulations of supernova-companion interactions and the subsequent post-impact evolution of the companion. Our results suggest that a surviving companion becomes brighter in two orders of magnitude and temporarily redder after the SN impact. The companion might be detectable with the JWST NIRCam short wavelength channel in a few years. Furthermore, the predicted magnitudes of surviving companions show a significant magnitude gradient around the peak. This could be another indicator to identify the surviving companion from a SE SN., Comment: 14 pages, 9 figures, accepted by ApJ

Recent theoretical and numerical studies of Type Ia supernova explosion within the single-degenerate scenario suggest that the non-degenerate companions could survive during the supernova impact and could be detectable in nearby supernova remnants. However, observational efforts show less promising evidence on the existence of surviving companions from the standard single-degenerate channels. The spin-up/spin-down models are possible mechanisms to explain the non-detection of surviving companions. In these models, the spin-up phase could increase the critical mass for explosion, leading to a super-Chandrasekhar mass explosion, and the spin-down phase could lead to extra mass loss and angular momentum redistribution. Since the spin-down timescale for the delayed explosion of a rotating white dwarf is unclear, in this paper, we explore a vast parameter space of main-sequence-like surviving companions via two-dimensional hydrodynamic simulations of supernova impact and the subsequent stellar evolution of surviving companions. Tight universal relations to describe the mass stripping effect, supernova kick, and depth of supernova heating are provided. Our results suggest that the not-yet detected surviving companions from observations of nearby Type Ia supernova remnants might favor low mass companions, short binary separation, or stronger supernova explosion energies than the standard singe-degenerate channels., Comment: 11 pages, 9 figures. Accepted by ApJ

We investigate the evolution of polycyclic aromatic hydrocarbon (PAH) abundance in a galaxy, which is a crucial step to understand the evolution of bright emission features in the mid-infrared range. We calculate the evolution of dust grain size distribution in a manner consistent with the physical conditions of the interstellar medium by post-processing our previous hydrodynamical simulation of an isolated disc galaxy. We also differentiate between aromatic and non-aromatic grains for carbonaceous dust species and explicitly considered the aromatization process. As a consequence, our model explains the metallicity dependence of PAH abundances in nearby galaxies well. The PAH abundance increase is driven particularly by the interplay between shattering and accretion (dust growth). The fast aromatization guarantees that the small carbonaceous grains trace PAHs very well. Since shattering and accretion are sensitive to the dust abundance, we predict that the PAH-to-dust abundance ratio increases as the metallicity increases. This is consistent with the observation data of nearby galaxies., Comment: Accepted by Monthly Notices of the Royal Astronomical Society (2019/9/5) 7 pages 4 figures