Tomás Müller | Searcharxiv

arXiv2019

A Comprehensive Analysis of Spitzer Supernovae

The mid-infrared (mid-IR) wavelength regime offers several advantages for following the late-time evolution of supernovae (SNe). First, the peaks of the SN spectral energy distributions shift toward longer wavelengths following the photospheric phase. Second, mid-IR observations suffer less from effects of interstellar extinction. Third, and perhaps most important, the mid-IR traces dust formation and circumstellar interaction at late-times (>100 days) after the radioactive ejecta component fades. The Spitzer Space Telescope has provided substantial mid-IR observations of SNe since its launch in 2003. More than 200 SNe have been targeted, but there are even more SNe that have been observed serendipitously. Here we present the results of a comprehensive study based on archival Spitzer/IRAC images of more than 1100 SN positions; from this sample, 119 SNe of various subclasses have been detected, including 45 SNe with previously unpublished mid-IR photometry. The photometry reveal significant amounts of warm dust in some cases. We perform an in-depth analysis to constrain the origin and heating mechanism of the dust, and present the resulting statistics.

astro-ph.HE↗

arXiv2017

The Nickel Mass Distribution of Normal Type II Supernovae

Core-collapse supernova explosions expose the structure and environment of massive stars at the moment of their death. We use the global fitting technique of Pejcha & Prieto (2015a,b) to estimate a set of physical parameters of 19 normal Type II SNe, such as their distance moduli, reddenings, $^{56}$Ni masses $M_{\rm Ni}$, and explosion energies $E_{\rm exp}$ from multicolor light curves and photospheric velocity curves. We confirm and characterize known correlations between $M_{\rm Ni}$ and bolometric luminosity at 50 days after the explosion, and between $M_{\rm Ni}$ and $E_{\rm exp}$. We pay special attention to the observed distribution of $M_{\rm Ni}$ coming from a joint sample of 38 Type~II SNe, which can be described as a skewed-Gaussian-like distribution between $0.005~M_{\odot}$ and $0.280~M_{\odot}$, with a median of $0.031~M_{\odot}$, mean of $0.046~M_{\odot}$, standard deviation of $0.048~M_{\odot}$ and skewness of $3.050$. We use two-sample Kolmogorov-Smirnov test and two-sample Anderson-Darling test to compare the observed distribution of $M_{\rm Ni}$ to results from theoretical hydrodynamical codes of core-collapse explosions with the neutrino mechanism presented in the literature. Our results show that the theoretical distributions obtained from the codes tested in this work, KEPLER and Prometheus Hot Bubble, are compatible with the observations irrespective of different pre-supernova calibrations and different maximum mass of the progenitors.

astro-ph.SR↗