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80 - X. Shao , K. Disseau , Y. B. Yang 2015
Based on the Sloan Digital Sky Survey DR 7, we investigate the environment, morphology and stellar population of bulgeless low surface brightness (LSB) galaxies in a volume-limited sample with redshift ranging from 0.024 to 0.04 and $M_r$ $leq$ $-18. 8$. The local density parameter $Sigma_5$ is used to trace their environments. We find that, for bulgeless galaxies, the surface brightness does not depend on the environment. The stellar populations are compared for bulgeless LSB galaxies in different environments and for bulgeless LSB galaxies with different morphologies. The stellar populations of LSB galaxies in low density regions are similar to those of LSB galaxies in high density regions. Irregular LSB galaxies have more young stars and are more metal-poor than regular LSB galaxies. These results suggest that the evolution of LSB galaxies may be driven by their dynamics including mergers rather than by their large scale environment.
We compare the host galaxies of 902 supernovae, including SNe Ia, SNe II and SNe Ibc, which are selected by cross-matching the Asiago Supernova Catalog with the SDSS Data Release 7. We further selected 213 galaxies by requiring the light fraction of spectral observations $>$15%, which could represent well the global properties of the galaxies. Among them, 135 galaxies appear on the Baldwin-Phillips-Terlevich diagram, which allows us to compare the hosts in terms of star-forming, AGNs (including composites, LINERs and Seyfert 2s) and Absorp (their related emission-lines are weak or non-existence) galaxies. The diagrams related to parameters D$_n$(4000), H$delta_A$, stellar masses, SFRs and specific SFRs for the SNe hosts show that almost all SNe II and most of SNe Ibc occur in SF galaxies, which have a wide range of stellar mass and low D$_n$(4000). The SNe Ia hosts as SF galaxies follow similar trends. A significant fraction of SNe Ia occurs in AGNs and Absorp galaxies, which are massive and have high D$_n$(4000). The stellar population analysis from spectral synthesis fitting shows that the hosts of SNe II have a younger stellar population than hosts of SNe Ia. These results are compared with those of the 689 comparison galaxies where the SDSS fiber captures less than 15% of the total light. These comparison galaxies appear biased towards higher 12+log(O/H) ($sim$0.1dex) at a given stellar mass. Therefore, we believe the aperture effect should be kept in mind when the properties of the hosts for different types of SNe are discussed.
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