S E M I N A R I

Departament d'Astronomia i Astrofísica
Universitat de València

    Photospheric Thermal Radiation From GRB Collapsar Jets

Akira Mizuta

Theory Center, Institute of Particle and Nuclear Studies, KEK (High Energy Accelerator Research Organization), Japan


Seminari del departament d'Astronomia i Astrofísica

Dilluns 25 juliol 2011

12:00


Resum

The gamma-ray bursts (GRBs) are one of the most luminous events in the universe. The radiation mechanism of GRB prompt emission is still underdebate. If a central engine makes a fireball, we can expect strong thermal emission from the photosphere. We have performed numerical hydrodynamic simulations of GRB jet propagation from collapsars and have derived photospheric thermal radiation by the post process. The light curves and spectra are derived for the observers at different viewing angles. We observe a few seconds time variability in the light curves caused by the internal mass density and Lorentz factor discontinuities in the jets.When we plot E_p-E_{iso} or E_p-L_{iso}_p, we can see similar dependence with empirical GRB cosmological relations such as Amati relation and Yonetoku relation.