Outflowing streams of matter or jets are a common phenomenon in the observeduniverse. The most extreme and powerful jets are relativistic, i.e., they travel at speedscomparable to the of speed light. Gamma Ray-Bursts (GRBs) and Active Galactic Nuclei(AGNs) are two sources of these relativistic jets. In this work I will...
One of the most important unresolved issues in gamma-ray burst (GRB) physics is the origin of the prompt gamma-ray spectrum. Its general non-thermal character and the softness in the X-ray band remain unexplained. We tackle these issues by performing Monte Carlo simulations of radiation-matter interactions in a scattering dominated photon-lepton...
Gamma Ray Bursts (GRBs) are the most energetic explosions in the Universe, producing up to $\sim10^{53}$ ergs of energy in the first few seconds of their emission -- the so-called prompt phase that is dominated by high energy X-ray and $\gamma$-ray photons. The very large luminosities released in these events...
The formation of carbonaceous and silicate precursor molecules to astrophysical dust grains is investigated. Using density functional theory (DFT) in combination with global optimization techniques, the ground-state binding energies of dust precursors are determined. These results are employed in atomistic nucleation theory (ANT) to predict the critical size and nucleation...