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Title: The host galaxies of fast-ejecta core-collapse supernovae

Abstract

Spectra of broad-lined Type Ic supernovae (SNe Ic-BL), the only kind of SN observed at the locations of long-duration gamma-ray bursts (LGRBs), exhibit wide features indicative of high ejecta velocities (∼0.1c). We study the host galaxies of a sample of 245 low-redshift (z < 0.2) core-collapse SNe, including 17 SNe Ic-BL, discovered by galaxy-untargeted searches, and 15 optically luminous and dust-obscured z < 1.2 LGRBs. We show that, in comparison with Sloan Digital Sky Survey galaxies having similar stellar masses, the hosts of low-redshift SNe Ic-BL and z < 1.2 LGRBs have high stellar mass and star formation rate densities. Core-collapse SNe having typical ejecta velocities, in contrast, show no preference for such galaxies. Moreover, we find that the hosts of SNe Ic-BL, unlike those of SNe Ib/Ic and SNe II, exhibit high gas velocity dispersions for their stellar masses. The patterns likely reflect variations among star-forming environments and suggest that LGRBs can be used as probes of conditions in high-redshift galaxies. They may be caused by efficient formation of massive binary progenitor systems in densely star-forming regions, or, less probably, a higher fraction of stars created with the initial masses required for an SN Ic-BL or LGRB. Finally, wemore » show that the preference of SNe Ic-BL and LGRBs for galaxies with high stellar mass and star formation rate densities cannot be attributed to a preference for low metal abundances but must reflect the influence of a separate environmental factor.« less

Authors:
;  [1];  [2];  [3]
  1. Department of Astronomy, University of California, Berkeley, CA 94720-3411 (United States)
  2. CCPP, New York University, 4 Washington Place, New York, NY 10003 (United States)
  3. NASA Goddard Space Flight Center, Code 662, Greenbelt, MD 20771 (United States)
Publication Date:
OSTI Identifier:
22356520
Resource Type:
Journal Article
Resource Relation:
Journal Name: Astrophysical Journal; Journal Volume: 789; Journal Issue: 1; Other Information: Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; ABUNDANCE; COMPARATIVE EVALUATIONS; COSMIC GAMMA BURSTS; DENSITY; DISPERSIONS; DUSTS; METALS; RED SHIFT; SPECTRA; SUPERNOVAE

Citation Formats

Kelly, Patrick L., Filippenko, Alexei V., Modjaz, Maryam, and Kocevski, Daniel. The host galaxies of fast-ejecta core-collapse supernovae. United States: N. p., 2014. Web. doi:10.1088/0004-637X/789/1/23.
Kelly, Patrick L., Filippenko, Alexei V., Modjaz, Maryam, & Kocevski, Daniel. The host galaxies of fast-ejecta core-collapse supernovae. United States. doi:10.1088/0004-637X/789/1/23.
Kelly, Patrick L., Filippenko, Alexei V., Modjaz, Maryam, and Kocevski, Daniel. 2014. "The host galaxies of fast-ejecta core-collapse supernovae". United States. doi:10.1088/0004-637X/789/1/23.
@article{osti_22356520,
title = {The host galaxies of fast-ejecta core-collapse supernovae},
author = {Kelly, Patrick L. and Filippenko, Alexei V. and Modjaz, Maryam and Kocevski, Daniel},
abstractNote = {Spectra of broad-lined Type Ic supernovae (SNe Ic-BL), the only kind of SN observed at the locations of long-duration gamma-ray bursts (LGRBs), exhibit wide features indicative of high ejecta velocities (∼0.1c). We study the host galaxies of a sample of 245 low-redshift (z < 0.2) core-collapse SNe, including 17 SNe Ic-BL, discovered by galaxy-untargeted searches, and 15 optically luminous and dust-obscured z < 1.2 LGRBs. We show that, in comparison with Sloan Digital Sky Survey galaxies having similar stellar masses, the hosts of low-redshift SNe Ic-BL and z < 1.2 LGRBs have high stellar mass and star formation rate densities. Core-collapse SNe having typical ejecta velocities, in contrast, show no preference for such galaxies. Moreover, we find that the hosts of SNe Ic-BL, unlike those of SNe Ib/Ic and SNe II, exhibit high gas velocity dispersions for their stellar masses. The patterns likely reflect variations among star-forming environments and suggest that LGRBs can be used as probes of conditions in high-redshift galaxies. They may be caused by efficient formation of massive binary progenitor systems in densely star-forming regions, or, less probably, a higher fraction of stars created with the initial masses required for an SN Ic-BL or LGRB. Finally, we show that the preference of SNe Ic-BL and LGRBs for galaxies with high stellar mass and star formation rate densities cannot be attributed to a preference for low metal abundances but must reflect the influence of a separate environmental factor.},
doi = {10.1088/0004-637X/789/1/23},
journal = {Astrophysical Journal},
number = 1,
volume = 789,
place = {United States},
year = 2014,
month = 7
}
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