English
 
Help Privacy Policy Disclaimer
  Advanced SearchBrowse

Item

ITEM ACTIONSEXPORT

Released

Journal Article

SN 2019ewu: A peculiar supernova with early strong carbon and weak oxygen features from a new sample of young SN Ic spectra

MPS-Authors
/persons/resource/persons203862

Vogl,  Christian
Stellar Astrophysics, MPI for Astrophysics, Max Planck Society;

External Resource
No external resources are shared
Fulltext (restricted access)
There are currently no full texts shared for your IP range.
Fulltext (public)
There are no public fulltexts stored in PuRe
Supplementary Material (public)
There is no public supplementary material available
Citation

Williamson, M., Vogl, C., Modjaz, M., Kerzendorf, W., Singhal, J., Boland, T., et al. (2023). SN 2019ewu: A peculiar supernova with early strong carbon and weak oxygen features from a new sample of young SN Ic spectra. The Astrophysical Journal Letters, 944(2): L49. doi:10.3847/2041-8213/acb549.


Cite as: https://hdl.handle.net/21.11116/0000-000D-468D-6
Abstract
With the advent of high-cadence, all-sky automated surveys, supernovae (SNe) are now discovered closer than ever to their dates of explosion. However, young premaximum light follow-up spectra of Type Ic SNe (SNe Ic), probably arising from the most-stripped massive stars, remain rare despite their importance. In this Letter, we present a set of 49 optical spectra observed with the Las Cumbres Observatory through the Global Supernova Project for 6 SNe Ic, including a total of 17 premaximum spectra, of which 8 are observed more than a week before V-band maximum light. This data set increases the total number of publicly available premaximum-light SN Ic spectra by 25%, and we provide publicly available SNID templates that will significantly aid in the fast identification of young SNe Ic in the future. We present a detailed analysis of these spectra, including Fe ii 5169 velocity measurements, O i 7774 line strengths, and continuum shapes. We compare our results to published samples of stripped SNe in the literature and find one SN in our sample that stands out. SN 2019ewu has a unique combination of features for an SN Ic: an extremely blue continuum, high absorption velocities, a P Cygni–shaped feature almost 2 weeks before maximum light that TARDIS radiative transfer modeling attributes to C ii rather than Hα, and weak or nonexistent O i 7774 absorption feature until maximum light.