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arXiv · 1603.07331

Post-maximum near infrared spectra of SN 2014J: A search for interaction signatures

D. J. Sand·E. Y. Hsiao·D. P. K. Banerjee·G. H. Marion·T. R. Diamond·V. Joshi·J. T. Parrent·M. M. Phillips·M. D. Stritzinger·V. Venkataraman
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Abstract

We present near infrared (NIR) spectroscopic and photometric observations of the nearby Type Ia SN 2014J. The seventeen NIR spectra span epochs from +15.3 to +92.5 days after $B$-band maximum light, while the $JHK_s$ photometry include epochs from $-$10 to +71 days. This data is used to constrain the progenitor system of SN 2014J utilizing the Pa$\beta$ line, following recent suggestions that this phase period and the NIR in particular are excellent for constraining the amount of swept up hydrogen-rich material associated with a non-degenerate companion star. We find no evidence for Pa$\beta$ emission lines in our post-maximum spectra, with a rough hydrogen mass limit of $\lesssim$0.1 $M_{\odot}$, which is consistent with previous limits in SN 2014J from late-time optical spectra of the H$\alpha$ line. Nonetheless, the growing dataset of high-quality NIR spectra holds the promise of very useful hydrogen constraints.

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D. J. Sand, E. Y. Hsiao, D. P. K. Banerjee, G. H. Marion, T. R. Diamond, V. Joshi, J. T. Parrent, M. M. Phillips, M. D. Stritzinger, V. Venkataraman. 2016-03-23. Post-maximum near infrared spectra of SN 2014J: A search for interaction signatures. https://doi.org/10.3847/2041-8205/822/1/l16

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