Related papers: A high mass progenitor for the Type Ic Supernova 2…

Type Ia supernovae are exploding stars that are used to measure the accelerated expansion of the Universe and are responsible for most of the iron ever produced. Although there is general agreement that the exploding star is a white dwarf…

Supernova (SN) 2004et is the eighth historical SN in the nearby spiral galaxy NGC 6946. Here we report on early photometric and spectroscopic monitoring of this object. SN 2004et is a Type II event, exhibiting a plateau in its light curves,…

We present follow-up imaging and spectroscopy and pre-explosion imaging of supernova (SN) 2025pht located in NGC 1637 at 12 Mpc. Our spectroscopy shows that SN 2025pht is a Type II SN with broad lines of hydrogen and with minimal…

We present a photometric catalog of 45 massive star clusters in the nuclear starburst of M 83 (NGC 5236), observed with the Hubble Space Telescope WFPC2, in both broad-band (F300W, F547M, and F814W) and narrow-band (F656N and F487N)…

Recent supernova and transient surveys have revealed an increasing number of non-terminal stellar eruptions. Though the progenitor class of these eruptions includes the most luminous stars, little is known of the pre-supernova mechanics of…

We age-date the stellar populations associated with 12 historic nearby core-collapse supernovae (CCSNe) and 2 supernova impostors, and from these ages, we infer their initial masses and associated uncertainties. To do this, we have obtained…

An overview of a spectroscopic survey for massive stars in the direction of the Galactic giant molecular complex G23.3-0.3 is presented (Messineo et al. 2010, and 2014 A&A submitted). This region is interesting because it is rich in HII…

Aims: We study the distribution of Wolf-Rayet (WR) stars and their subtypes with respect to their host galaxy light distribution. We thus want to investigate whether WR stars are potential progenitors of stripped-envelope core-collapse…

We investigate the stellar populations in the star forming ring of the luminous infrared galaxy NGC 7469. We use Hubble Space Telescope multi-wavelength (UV through NIR) imaging complemented with new K-band ground-based long-slit…

We aim to understand the progenitor channels of CCSNe via a statistical study of the ages of their environments. We compiled a large and minimally biased sample of 129 CCSNe discovered by untargeted wide-field transient surveys and with…

We present HST/WFPC2, GALEX and Chandra observations of the position of the type Ia supernova SN2007sr in the Antennae galaxies, taken before the explosion. No source is found in any of the observations, allowing us to put interesting…

We present a new analysis of the properties of the young massive star clusters, which demonstrates that these objects are plausible progenitors of old globular clusters (GCs). The method is based on the tight relationship for old GCs…

XMMU J1229+0151 is a rich galaxy cluster with redshift z=0.975, that was serendipitously detected in X-rays within the scope of the XMM-Newton Distant Cluster Project. HST/ACS observations in the i775 and z850 passbands, as well as…

We examine star clusters in the irregular, starburst galaxy NGC 1569 from HST images. In addition to the two known super star clusters, we identify 45 other clusters that are compact but resolved. Integrated UVI colors of the clusters span…

We have observed the center of the Local Group dwarf irregular galaxy IC 1613 with WFPC2 aboard the Hubble Space Telescope in the F439W, F555W, and F814W filters. We find a dominant old stellar population (aged ~7 Gyr), identifiable by the…

Thirteen explosion sites of type II-P and II-L supernovae in nearby galaxies have been observed using integral field spectroscopy, enabling both spatial and spectral study of the explosion sites. We used the properties of the parent stellar…

We present a sample of Type Icn supernovae (SNe Icn), a newly-discovered class of transients characterized by their interaction with H- and He-poor circumstellar material (CSM). This sample is the largest collection of SNe Icn to date and…

Recent discoveries have put the picture of stellar clusters being simple stellar populations into question. In particular, the color-magnitude diagrams of intermediate age (1-2 Gyr) massive clusters in the Large Magellanic Cloud (LMC) show…

We explore properties of Type Ib and IIb SN progenitors that are produced by stable mass transfer in binary systems, using a new grid of stellar evolution models from an initial primary mass in the range of 10 - 18 $\mathrm{M_\odot}$ at…

We have identified a luminous star at the position of supernova (SN) 2011dh/PTF11eon, in pre-SN archival, multi-band images of the nearby, nearly face-on galaxy Messier 51 (M51) obtained by the Hubble Space Telescope with the Advanced…