Related papers: Thermal and non-thermal emission from circumstella…
The explosion of a core collapse supernova drives a powerful shock front into the wind from the progenitor star. A layer of shocked circumstellar gas and ejecta develops that is subject to hydrodynamic instabilities. The hot gas can be…
We performed a series of hydrodynamical calculations of an ultra-relativistic jet propagating through a massive star and the circumstellar matter to investigate the interaction between the ejecta and the circumstellar matter. We succeed in…
We have developed a simple model to investigate the modifications of the hydrodynamics and non-equilibrium ionization X-ray emission in young supernova remnants due to nonlinear particle acceleration. In nonlinear, diffusive shock…
The fast shocks that characterize supernova remnants heat circumstellar and ejecta material to extremely high temperatures, resulting in significant X-ray emission. The X-ray spectrum from an SNR carries a wealth of information about the…
Hydrodynamical interaction of spherical ejecta freely expanding at mildly relativistic speeds into an ambient cold medium is studied in semi-analytical and numerical ways to investigate how ejecta produced in energetic stellar explosions…
The X-ray emission from the circumstellar interaction in Type II supernovae with a dense circumstellar medium is calculated. In Type IIL and Type IIn supernovae mass loss rates are generally high enough for the region behind the reverse…
The interaction of post-explosion supernova ejecta with the surrounding circumstellar medium creates emission across the electromagnetic spectrum. Since the circumstellar medium is created by the mass lost from the progenitor star, it…
I present a review of nonthermal processes in the large scale structure of the universe. After examining the properties of cosmological shock waves and their role as particle accelerators, I discuss the main observational facts, from radio…
We examine and analyze the physical processes that should be taken into account when modeling young type-Ia SNRs, with ages of several hundred years. It is shown, that energy losses in the metal-rich ejecta can be essential for remnants…
Context: Multiwavelength observations of supernova remnants can be explained within the framework of the diffusive shock acceleration theory, which allows effective conversion of the explosion energy into cosmic rays. Although the models of…
We perform a series of two-dimensional radiation-hydrodynamic simulations of the collision between supernova ejecta and circumstellar media (CSM). The hydrodynamic interaction of a fast flow and the surrounding media efficiently dissipates…
Supernova remnants are beautiful astronomical objects that are also of high scientific interest, because they provide insights into supernova explosion mechanisms, and because they are the likely sources of Galactic cosmic rays. X-ray…
We investigate broad-band emission from supernova ejecta powered by a relativistic wind from a central compact object. A recent two-dimensional hydrodynamic simulation studying the dynamical evolution of supernova ejecta with a central…
Supernova remnants are believed to be the major contributors to Galactic cosmic rays. In this paper, we explore how the non-thermal emission from young remnants can be used to probe the production of energetic particles at the shock (both…
Core-collapse supernovae are found in galaxies with ongoing star-formation. In a starburst galaxy hosting an active galactic nucleus with a relativistic jet, supernovae can take place inside the jet. The collision of the supernova ejecta…
The interaction of supernova ejecta with a surrounding circumstellar medium (CSM) generates a strong shock which can convert the ejecta kinetic energy into observable radiation. Given the diversity of potential CSM structures (arising from…
We describe the propagation of supernova shocks within the surrounding medium, which may be due to mass-loss from the progenitor star. The structure and density profile of the ejected material and surrounding medium are considered. Shock…
In a supernova explosion, the ejecta interacting with the surrounding circumstellar medium (CSM) give rise to variety of radiation. Since CSM is created from the mass lost from the progenitor star, it carries footprints of the late time…
Context. There is a population of runaway stars that move at extremely high speeds with respect to their surroundings. The fast motion and the stellar wind of these stars, plus the wind-medium interaction, can lead to particle acceleration…
The main goal of this thesis is to study the physical processes that can produce non-thermal emission at high energies in astrophysical objects capable to accelerate particles up to relativistic velocities. In particular, we have studied…