Theory Group


Cosmic Reionization

Early Universe

First Stars & Galaxies

Fundamental Physics

Structure Formation

Extragalactic Astrophysics

Clusters of Galaxies

Theoretical & Computational Astrophysics

Galactic Evolution

ISM and Star Formation

Milky Way Evolution

Planetary Sciences


Planet Formation

Stellar Astrophysics


Gamma-ray Bursts

Neutron Stars & Magnetars


White Dwarfs

Theory Group : Stellar Astrophysics : Gamma-ray Bursts

Pawan Kumar, Milos Milosavljevic

ADS | astro-ph

Pawan Kumar  



Research Interests

Gamma-ray bursts; helioseismology; binary stars; tidal interaction; accretion disks; cosmology.

Group Areas

Theory, Asteroseismology, Gamma-ray Bursts

ADS | astro-ph

Milos Milosavljevic  

Associate Professor


Research Interests

Massive black holes; the Galactic center; galaxy formation; galaxy clusters; plasma astrophysics.

Group Areas

Theory, Gamma-ray Bursts, Clusters of Galaxies, Theoretical & Computational Astrophysics, Black Holes & AGN

The formation of a thick accretion disk around the black hole at the center of a collapsing star. A parcel of gas which has a circular orbit about the axis of rotation of the star at a radius r before core collapse (red dashed line), goes into free-fall after core collapse (solid red line), colliding with its counterpart from the opposite side of the equatorial plane (blue dashed and solid lines) at a distance req and forming a disk in the equatorial (x-y) plane (light gray). After the parcels of gas collide, they fall further toward the black hole (black) until their angular momentum allows them to become centrifugally supported in an accretion disk (dark gray). The set of axes is shown for orientation; in our calculations, the origin of this coordinate system is at the center of the star.


Mass Fall-back and Accretion in the Central Engine of Gamma-Ray Bursts astro-ph