Related papers: Supercollapsars and their X-ray Bursts

In order to constrain the initial mass function (IMF) of the first generation of stars (Population III), we investigate the fragmentation properties of metal-free gas in the context of a hierarchical model of structure formation. We…

Long-duration gamma-ray bursts (LGRBs) associated with supernovae (SNe) are possibly born out of the death of a massive star. After the star collapses, a stellar-mass black hole (BH) is formed, surrounded by a hyperaccretion disk with…

We review the current status of knowledge concerning the early phases of star formation during cosmic dawn. This includes the first generations of stars forming in the lowest mass dark matter halos in which cooling and condensation of gas…

Forming massive stars launch outflows of magnetic origin, which in fact serve as a marker for finding sites of massive star formation. However, both the theoretical and observational study of the mechanisms that intervene in the formation…

Using a collapsar progenitor model of MacFadyen & Woosley we have simulated the propagation of an axisymmetric jet through a collapsing rotating massive star with the GENESIS multi-dimensional relativistic hydrodynamic code. The jet forms…

Although fundamental for astrophysics, the processes that produce massive stars are not well understood. Large distances, high extinction, and short timescales of critical evolutionary phases make observations of these processes…

We investigate the triggering of star formation in clouds that form in Galactic scale flows as the ISM passes through spiral shocks. We use the Lagrangian nature of SPH simulations to trace how the star forming gas is gathered into…

We discuss the high energy neutrino emission from gamma-ray bursts resulting from the earliest generation (`population III') stars forming in the Universe, whose core collapses into a black hole. These gamma-ray bursts are expected to…

We present a model for the formation of massive black holes ($\sim 1000 \msun$) due to stellar-dynamical processes in the first stellar clusters formed at early cosmic times ($z\sim10-20$). The high redshift black hole seeds form as a…

Long duration gamma-ray bursts (GRBs) are thought to be produced by the core-collapse of a rapidly-rotating massive star. This event generates a highly relativistic jet and prompt gamma-ray and X-ray emission arises from internal shocks in…

The discovery of a population of superluminous supernovae (SLSNe), with peak luminosities a factor of ~100 brighter than normal SNe (typically SLSNe have M_V <-21), has shown an unexpected diversity in core-collapse supernova properties.…

The radiation observed by blazars is believed to originate from the transformation of bulk kinetic energy of relativistic jets into random energy. A simple way to achieve this is to have an intermittent central power source, producing…

Long Gamma-Ray Bursts (LGRBs) are often associated with the collapse of stripped-envelope massive stars. Powerful relativistic jets drill through the stellar envelope before the gamma emission. Previous hydrodynamical studies imposed jets…

Multispectral studies of nearby, forming stars provide insights into all classes of accreting systems. Objects which have magnetic fields, spin, and accrete produce jets and collimated outflows. Jets are seen in systems ranging from brown…

We propose the Wind of Fast Rotating Massive Stars scenario to explain the origin of the abundance anomalies observed in globular clusters. We compute and present models of fast rotating stars with initial masses between 20 and 120 Msun for…

Many giant stars are magnetically active, which causes rotational variability, chromospheric emission lines, and X-ray emission. Large outbursts in these emission features can set limits on the magnetic field strength and thus constrain the…

Recent studies suggest that the initial mass function (IMF) of the first stars was likely to be extremely top-heavy, unlike what is observed at present. We propose a scenario to generate fragmentation to lower masses once the first massive…

Several models have predicted that stars could form inside galactic outflows and that this would be a new major mode of galaxy evolution. Observations of galactic outflows have revealed that they host large amounts of dense and clumpy…

The current generation of millimeter interferometers have revealed a population of compact (r <~ 0.1 pc), massive (M ~ 100 Msun) gas cores that are the likely progenitors of massive stars. I review models for the evolution of these objects…

Supernovae connected with long-duration gamma-ray bursts (GRBs) are hyper-energetic explosion resulting from the collapse of very massive stars (about 40Mo, where Mo is the mass of the Sun) stripped of their outher hydrogen and helium…