2018/01/04 by Christopher William Bullivant, Christopher Bullivant, Nathan Smith +20
Physics and Astronomy · #Astronomy #Astrophysics #Gamma-ray bursts and supernovae #Physics #Supernova #Type (biology) #astro-ph.HE #astro-ph.SR
paper · pdf · doi:10.1093/mnras/sty045
MNRAS accepted. 28 pages, 23 figures, 8 tables
arxiv created 2018/01/04 · openalex publication_date 2018/01/07 · openalex created_date 2018/01/12 · arxiv updated 2018/01/24 · openalex updated_date 2026/08/06
We present photometry and spectroscopy of SN2013fs and SN2013fr in the first 100 days post-explosion. Both objects showed transient, relatively narrow Hα emission lines characteristic of SNeIIn, but later resembled normal SNeII-P or SNeII-L, indicative of fleeting interaction with circumstellar material (CSM). SN2013fs was discovered within 8hr of explosion. Its light curve exhibits a plateau, with spectra revealing strong CSM interaction at early times. It is a less luminous version of the transitional SNIIn PTF11iqb, further demonstrating a continuum of CSM interaction intensity between SNeII-P and IIn. It requires dense CSM within 6.5×1014~cm of the progenitor, from a phase of advanced pre-SN mass loss shortly before explosion. Spectropolarimetry of SN2013fs shows little continuum polarization, but noticeable line polarization during the plateau phase. SN2013fr morphed from a SNIIn at early times to a SNII-L. After the first epoch its narrow lines probably arose from host-galaxy emission, but the bright, narrow Hα emission at early times may be intrinsic. As for SN2013fs, this would point to a short-lived phase of strong CSM interaction if proven to be intrinsic, suggesting a continuum between SNeIIn and II-L. It is a low-velocity SNII-L, like SN2009kr but more luminous. SN2013fr also developed an IR excess at later times, due to warm CSM dust that require a more sustained phase of strong pre-SN mass loss.