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# The late-time light curve of the Type Ia supernova SN 2011fe

Dimitriadis, G., Sullivan, M., Kerzendorf, W., Ruiter, A. J., Seitenzahl, I. R., Taubenberger, S., Doran, G. B., Gal-Yam, A., Laher, R. R., Maguire, K., Nugent, P., Ofek, E. O. and Surace, J. (2017) The late-time light curve of the Type Ia supernova SN 2011fe. Monthly Notices of the Royal Astronomical Society, 468 (4), 3798-3812.

Record type: Article

## Abstract

We present late-time optical $R$-band imaging data from the Palomar Transient Factory (PTF) for the nearby type Ia supernova SN 2011fe. The stacked PTF light curve provides densely sampled coverage down to $R\simeq22$ mag over 200 to 620 days past explosion. Combining with literature data, we estimate the pseudo-bolometric light curve for this event from 200 to 1600 days after explosion, and constrain the likely near-infrared contribution. This light curve shows a smooth decline consistent with radioactive decay, except over ~450 to ~600 days where the light curve appears to decrease faster than expected based on the radioactive isotopes presumed to be present, before flattening at around 600 days. We model the 200-1600d pseudo-bolometric light curve with the luminosity generated by the radioactive decay chains of $^{56}$Ni, $^{57}$Ni and $^{55}$Co, and find it is not consistent with models that have full positron trapping and no infrared catastrophe (IRC); some additional energy escape other than optical/near-IR photons is required. However, the light curve is consistent with models that allow for positron escape (reaching 75% by day 500) and/or an IRC (with 85% of the flux emerging in non-optical wavelengths by day 600). The presence of the $^{57}$Ni decay chain is robustly detected, but the $^{55}$Co decay chain is not formally required, with an upper mass limit estimated at 0.014 M$_{\odot}$. The measurement of the $^{57}$Ni/$^{56}$Ni mass ratio is subject to significant systematic uncertainties, but all of our fits require a high ratio >0.031 (>1.3 in solar abundances).

Full text not available from this repository.

Accepted/In Press date: 16 March 2016
e-pub ahead of print date: 22 March 2017
Published date: 22 March 2017
Organisations: Astronomy Group, Physics & Astronomy

## Identifiers

Local EPrints ID: 408292
URI: https://eprints.soton.ac.uk/id/eprint/408292
ISSN: 0035-8711
PURE UUID: 75c6174a-1d3d-4c97-93c0-c0c05ef61691
ORCID for M. Sullivan: orcid.org/0000-0001-9053-4820

## Catalogue record

Date deposited: 19 May 2017 04:02

## Contributors

Author: M. Sullivan
Author: W. Kerzendorf
Author: A. J. Ruiter
Author: I. R. Seitenzahl
Author: S. Taubenberger
Author: G. B. Doran
Author: A. Gal-Yam
Author: R. R. Laher
Author: K. Maguire
Author: P. Nugent
Author: E. O. Ofek
Author: J. Surace