PROGENITOR DIAGNOSTICS FOR STRIPPED CORE-COLLAPSE SUPERNOVAE: MEASURED METALLICITIES AT EXPLOSION SITES

Journal Article · Sun Apr 10 04:00:00 EDT 2011 · Astrophysical Journal Letters

DOI:https://doi.org/10.1088/2041-8205/731/1/L4· OSTI ID:21562755

Modjaz, M; Bloom, J S; Filippenko, A V; Perley, D; Silverman, J M ^[1]; Kewley, L ^[2]

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1. Department of Astronomy, University of California, Berkeley, CA 94720-3411 (United States)
2. Institute for Astronomy, University of Hawaii, 2680 Woodlawn Drive, Honolulu, HI 96822 (United States)

Metallicity is expected to influence not only the lives of massive stars but also the outcome of their deaths as supernovae (SNe) and gamma-ray bursts (GRBs). However, there are surprisingly few direct measurements of the local metallicities of different flavors of core-collapse SNe (CCSNe). Here, we present the largest existing set of host-galaxy spectra with H II region emission lines at the sites of 35 stripped-envelope CCSNe. We derive local oxygen abundances in a robust manner in order to constrain the SN Ib/c progenitor population. We obtain spectra at the SN sites, include SNe from targeted and untargeted surveys, and perform the abundance determinations using three different oxygen-abundance calibrations. The sites of SNe Ic (the demise of the most heavily stripped stars, having lost both H and He layers) are systematically more metal rich than those of SNe Ib (arising from stars that retained their He layer) in all calibrations. A Kolmogorov-Smirnov test yields the very low probability of 1% that SN Ib and SN Ic environment abundances, which are different on average by {approx}0.2 dex (in the Pettini and Pagel scale), are drawn from the same parent population. Broad-lined SNe Ic (without GRBs) occur at metallicities between those of SNe Ib and SNe Ic. Lastly, we find that the host-galaxy central oxygen abundance is not a good indicator of the local SN metallicity; hence, large-scale SN surveys need to obtain local abundance measurements in order to quantify the impact of metallicity on stellar death.

• OSTI ID: 21562755
• Journal Information: Astrophysical Journal Letters, Journal Name: Astrophysical Journal Letters Journal Issue: 1 Vol. 731; ISSN 2041-8205
• Country of Publication: United States
• Language: English

Related Subjects

79 ASTRONOMY AND ASTROPHYSICS
ABUNDANCE
BINARY STARS
CALIBRATION
COSMIC GAMMA BURSTS
COSMIC RADIATION
ELEMENT ABUNDANCE
ELEMENTS
EMISSION
ERUPTIVE VARIABLE STARS
GALAXIES
IONIZING RADIATIONS
METALS
NONMETALS
OXYGEN
PRIMARY COSMIC RADIATION
RADIATIONS
STARS
SUPERNOVAE
VARIABLE STARS