Related papers: The NGC 300 Transient: An Alternative Method For M…
Mergers of neutron stars (NS+NS) or neutron stars and stellar mass black holes (NS+BS) eject a small fraction of matter with a sub-relativistic velocity. Upon rapid decompression nuclear density medium condenses into neutron rich nuclei,…
We present the results of a 10.5 yr, volume limited (28 Mpc) search for supernova (SN) progenitor stars. We compile all SNe discovered within this volume (132, of which 27% are type Ia) and determine the relative rates of each sub-type from…
M85 optical transient 2006-1 (M85 OT 2006-1) is the most luminous member of the small family of V838 Mon-like objects, whose nature is still a mystery. This event took place in the Virgo cluster of galaxies and peaked at an absolute…
Recent modeling of hydrogen-rich Type II supernova (SN II) light curves suggests the presence of dense circumstellar material (CSM) surrounding the exploding progenitor stars. This has important implications for the activity and structure…
We illustrate the observability of the end stages of the earliest (Population III) stars at high redshifts $z \gtrsim 10$, using the recently observed transient, GN-z11-flash as an example. We find that the observed spectrum of this…
Astronomical transients, such as supernovae and other rare stellar explosions, have been instrumental in some of the most significant discoveries in astronomy. New astronomical sky surveys will soon record unprecedented numbers of…
We put constraints on the properties of the progenitors of peculiar calcium-rich transients using the distribution of locations within their host galaxies. We confirm that this class of transients do not follow the galaxy stellar mass…
The 2008 optical transient in NGC 300 is one of a growing class of intermediate-luminosity transients that brighten several orders of magnitude from a previously optically obscured state. The origin of their eruptions is not understood. Our…
AIMS: The main goal of this work is to study possible signs of asymmetry in the bright optical transient in NGC300, with the aim of getting independent information on the explosion mechanism, the progenitor star and its circumstellar…
We have begun a program to search for supernovae and other transients in the fields of galaxy clusters with the 2.3m Bok Telescope on Kitt Peak. We present our automated photometric methods for data reduction, efficiency characterization,…
The evolution leading to the formation of a neutron star in the very young Westerlund 1 star cluster is investigated. The turnoff mass has been estimated to be 35 Msun, indicating a cluster age ~ 3-5 Myr. The brightest X-ray source in the…
The long-duration gamma-ray burst (GRB) 030329, associated with supernova (SN) 2003dh, occurred inside a star-forming dwarf galaxy at redshift $z=0.1685$. The low redshift, and a rich set of archival Hubble Space Telescope (HST) images,…
A central challenge in observational studies of galaxy formation is how to associate progenitor galaxies with their descendants at lower redshifts. One promising approach is to link galaxies at fixed number density, rather than fixed…
The origin of young star clusters represents a major challenge for modern stellar astrophysics. While stellar rotation partially explains the colour spread observed along main-sequence turn-offs, i.e. where stars leave the main-sequence…
We compute an extensive set of early-time spectra of supernovae interacting with circumstellar material using the radiative transfer code CMFGEN. Our models are applicable to events observed from 1 to a few days after explosion. Using these…
We present a comprehensive theoretical study, within a fully realistic semi-analytical framework, of the photometric properties of early-type progenitors in the redshift range 0<z<1, as a function of the luminosity and local environment of…
The stars that end their lives as supernovae (SNe) have been directly observed in only a handful of cases, due mainly to the extreme difficulty in identifying them in images obtained prior to the SN explosions. Here we report the…
We have extracted PSF-fitted stellar photometry from near-ultraviolet, optical and near-infrared images, obtained with the Hubble Space Telescope, of the nearby (D ~ 5.5 Mpc) SBm galaxy NGC 1311. The ultraviolet and optical data reveal a…
The progenitors of Type II-P supernovae (SN) have been confirmed to be red supergiants. However, the upper mass limit of the directly probed progenitors is much lower than that predicted by current theories, and the accurate determination…
Over the last 15 years, the supernova community has endeavoured to identify progenitor stars of core-collapse supernovae in high resolution archival images of their galaxies.This review compiles results (from 1999 - 2013) in a distance…