摘要：The metallicity of a supernova progenitor, together with its mass, is one of the main
parameters that can rule the progenitor’s fate. We present the second study of nearby
supernova (SN) host galaxies (0.005
10 dex)
by targeted searches. We neither found evidence that the metallicity at the SN location
differs from the average metallicity at the galactocentric distance of the SNe. By
extending our SN sample with published metallicities at the SN location, we are able to
study the metallicity distributions for all SN subtypes split into SN discovered in
targeted and untargeted searches. We confirm a bias toward higher host masses and
metallicities in the targeted searches. By combining data from targeted and untargeted
searches, we found a sequence from higher to lower local metallicity: SN Ia, Ic, and II
show the highest metallicity, which is significantly higher than those of SN Ib, IIb, and
Ic-BL. Our results support the scenario according to which SN Ib result from binary
progenitors. Additionally, at least part of the SN Ic are the result of single massive
stars that were stripped of their outer layers by metallicity-driven winds. We studied
several proxies of the local metallicity that are frequently used in the literature and
found that the total host metallicity allows estimating the metallicity at the SN location
with an accuracy better than 0.08 dex and very small bias. In addition, weak AGNs that
cannot be seen in the total spectrum may weakly bias (by 0.04 dex) the metallicity
estimate that is derived from the galaxy-integrated spectrum.
关键词：galaxies: general;galaxies: abundances;supernovae: general
