Early observations of the nearby type Ia supernova SN 2015F
R. Cartier, M. Sullivan, R. Firth, G. Pignata, P. Mazzali, K. Maguire,, M. J. Childress, I. Arcavi, C. Ashall, B. Bassett, S. M. Crawford, C., Frohmaier, L. Galbany, A. Gal-Yam, G. Hosseinzadeh, D. A. Howell, C. Inserra,, J. Johansson, E. K. Kasai, C. McCully, S. Prajs

TL;DR
This paper presents early photometric and spectroscopic observations of SN 2015F, revealing unique spectral features, evidence of mixing in the ejecta, and potential detection of photospheric Al II, contributing new insights into SN Ia diversity.
Contribution
It provides the first evidence of photospheric Al II in SN Ia spectra and offers detailed early-time data constraining the explosion physics and composition.
Findings
Detection of photospheric C II absorption until -4 days.
Strong high-velocity Ca II at -10 days.
Presence of Al II feature possibly indicating non-low-metallicity progenitor.
Abstract
We present photometry and time-series spectroscopy of the nearby type Ia supernova (SN Ia) SN 2015F over days to days relative to maximum light, obtained as part of the Public ESO Spectroscopic Survey of Transient Objects (PESSTO). SN 2015F is a slightly sub-luminous SN Ia with a decline rate of mag, placing it in the region between normal and SN 1991bg-like events. Our densely-sampled photometric data place tight constraints on the epoch of first light and form of the early-time light curve. The spectra exhibit photospheric C II absorption until days, and high-velocity Ca II is particularly strong at days at expansion velocities of 23000\kms. At early times, our spectral modelling with syn++ shows strong evidence for iron-peak elements (Fe II, Cr II, Ti II, and V II) expanding at velocities km…
Peer Reviews
No public reviews on file for this paper yet. If you reviewed it on a platform where reviews are public (OpenReview, ICLR, NeurIPS, ICML), you can paste yours below so the community can read it here.
Videos
No videos yet. Explain this paper in a talk, walkthrough, or lecture? Add one.
