Spitzer observations of SN 2014J and properties of mid-IR emission in Type Ia supernovae

TL;DR

This study uses Spitzer mid-infrared data to analyze SN 2014J and other Type Ia supernovae, creating composite light curves and constraining circumstellar dust, revealing their homogeneity and limited dust presence.

Contribution

The paper presents the first composite mid-IR light-curve templates for SNe Ia and constrains circumstellar dust around SN 2014J and other supernovae, highlighting their homogeneity in mid-IR emission.

Findings

SNe Ia form a homogeneous class at mid-IR wavelengths.

No significant mid-IR excess detected around SN 2014J, SN 2006X, and SN 2007le.

Upper limits on circumstellar dust mass are established.

Abstract

SN 2014J in M82 is the closest Type Ia supernova (SN Ia) in decades. The proximity allows for detailed studies of supernova physics and provides insights into the circumstellar and interstellar environment. In this work we analyze Spitzer mid-IR data of SN 2014J in the 3.6 and 4.5 {\mu}m wavelength range, together with several other nearby and well-studied SNe Ia. We compile the first composite mid-IR light-curve templates from our sample of SNe~Ia, spanning the range from before peak brightness well into the nebular phase. Our observations indicate that SNe Ia form a very homogeneous class of objects at these wavelengths. Using the low-reddening supernovae for comparison, we constrain possible thermal emission from circumstellar dust around the highly reddened SN 2014J. We also study SNe 2006X and 2007le, where the presence of matter in the circumstellar environment has been suggested. No significant mid-IR excess is detected, allowing us to place upper limits on the amount of pre-existing dust in the circumstellar environment. For SN 2014J, $M_{dust} < 10^{-5}$ M$_{\odot}$ within $r_{dust} \sim 10^{17}$ cm, which is insufficient to account for the observed extinction. Similar limits are obtained for SNe 2006X and 2007le.