Physics of Gamma-Ray Bursts Prompt Emission

Abstract EN

In recent years, our understanding of gamma-ray bursts (GRB) promptemission has been revolutionized, due to a combination of newinstruments, new analysis methods, and novel ideas.

In this review, Idescribe the most recent observational results and currenttheoretical interpretation.

Observationally, a major development isthe rise of time resolved spectral analysis.

These led to (I)identification of a distinguished high energy component, with GeVphotons often seen at a delay and (II) firm evidence for theexistence of a photospheric (thermal) component in a large number ofbursts.

These results triggered many theoretical efforts aimed atunderstanding the physical conditions in the inner jet regions.

I highlight some areas of active theoreticalresearch.

These include (I) understanding the role played by magneticfields in shaping the dynamics of GRB outflow and spectra; (II)understanding the microphysics of kinetic and magnetic energytransfer, namely, accelerating particle to high energies in both shockwaves and magnetic reconnection layers; (III) understanding howsubphotospheric energy dissipation broadens the “Planck” spectrum;and (IV) geometrical light aberration effects.

I highlight some ofthese efforts and point towards gaps that still exist in ourknowledge as well as promising directions for the future.