We use a sample of 43,690 galaxies selected from the Sloan Digital Sky Survey Data
Release 4 to study the systematic effects of specific star formation rate (SSFR) and galaxy …

We have obtained new spectrophotometric data for 28 H ii regions in the spiral galaxy NGC
300, a member of the nearby Sculptor Group. The detection of several auroral lines …

We present very deep spectrophotometry of 14 bright extragalactic H ii regions belonging to
spiral, irregular, and blue compact galaxies. The data for 13 objects were taken with the …

The dispersion in chemical abundances provides a very strong constraint on the processes
that drive the chemical enrichment of galaxies. Due to its proximity, the spiral galaxy M33 …

When combined with infrared observations with the Spitzer telescope (3 to 160 μm), the
Herschel Space Observatory now fully samples the thermal dust emission up to 500 μm and …

We test the hypothesis that the host galaxies of long-duration gamma-ray bursts (GRBs) as
well as quasar-selected damped Lyα (DLA) systems are drawn from the population of UV …

Aims. The estimate of radial abundance gradients in high-redshift galaxies allows to
constrain their star formation history and their interplay with the surrounding intergalactic …

Recent observations have revealed that some Type Ia supernovae exhibit narrow, time-
variable Na i D absorption features. The origin of the absorbing material is controversial, but …

We present a new determination of the metallicity gradient in M33, based on Keck LRIS
measurements of oxygen abundances using the temperature-sensitive emission line [O iii] …

Despite the many successes that modern massive star evolutionary theory has enjoyed,
reproducing the apparent trend in the relative number of red supergiants (RSGs) and Wolf …