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This content will become publicly available on February 28, 2026

Title: Supernova Siblings and Spectroscopic Host Galaxy Properties
Over the past century, supernova (SN) searches have detected multiple supernovae (SNe) in hundreds of individual galaxies. So-called SN siblings discovered in the same galaxy present an opportunity to constrain the dependence of the properties of SNe on those of their host galaxies. To investigate whether there is a connection between sibling SNe in galaxies that have hosted multiple SNe and the properties of galaxies, we have acquired integrated optical spectroscopy of 59 galaxies with multiple core-collapse SNe. Perhaps surprisingly, a strong majority of host galaxy spectra fall within the composite region of the Baldwin–Phillips–Terlevich (BPT) diagram. We find a statistically significant difference (Kolmogorov–Smirnov test p-value = 0.044) between the distributions of the [Nii]λ6583/Hα of galaxies that have hosted a majority of SNe Ibc and those that have hosted a majority of Type II supernovae (SNe II), where the majority of Type Ibc supernovae (SNe Ibc) galaxies have, on average, higher ratios. The difference between the distributions of [Nii]λ6583/Hα may arise from either increased contribution from active galactic nuclei or low-ionization nuclear emission-line regions in SNe Ibc host galaxies, greater metallicity for SNe Ibc host galaxies, or both. When comparing the inferred oxygen abundance and the ionization parameter for the galaxies in the star-forming region on the BPT diagram, we find statistically significant differences between the distributions for SNe Ibc hosts and SNe II hosts (p= 0.008 and p= 0.001, respectively), as well as SNe Ib hosts and SNe II hosts (p = 0.030 and p= 0.006, respectively). We also compare the Hα equivalent width distributions, also integrated across the galaxies, and find no significant difference.  more » « less
Award ID(s):
2308051 1922512 2152746
PAR ID:
10584970
Author(s) / Creator(s):
; ; ; ;
Publisher / Repository:
Astrophysical Journal
Date Published:
Journal Name:
The Astrophysical Journal
Volume:
981
Issue:
1
ISSN:
0004-637X
Page Range / eLocation ID:
97
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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