Pre-nebular light curves of type I supernovae

W. David Arnett; Christopher L. Fryer; Thomas Matheson

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arXiv · 1611.08746

Pre-nebular light curves of type I supernovae

W. David Arnett·Christopher L. Fryer·Thomas Matheson

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Abstract

We compare analytic predictions of supernova light curves with recent high quality data from SN2011fe (Ia), from KSN2011b (Ia), and the Palomar Transient Factory (PTF) and the La Silla-QUEST variability survey (LSQ) (Ia). Because of the steady, fast cadence of observations, KSN2011b provides unique new information on SNe Ia: the smoothness of the light curve, which is consistent with significant large-scale mixing during the explosion, possibly due to 3D effects (e.g., Rayleigh-Taylor instabilities), and provides support for a slowly-varying leakage (mean opacity). For a more complex light curve (SN2008D, SNIb), we separate the luminosity due to multiple causes and indicate the possibility of a radioactive plume. The early rise in luminosity is shown to be affected by the opacity (leakage rate) for thermal and non-thermal radiation. A general derivation of Arnett's rule again shows that it depends upon {\em all} processes heating the plasma, not just radioactive ones, so that SNe Ia will differ from SNe Ibc if the latter have multiple heating processes.

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W. David Arnett, Christopher L. Fryer, Thomas Matheson. 2017-08-13. Pre-nebular light curves of type I supernovae. https://arxiv.org/abs/1611.08746

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