Gamma ray bursts versus OB associations: do they trigger star formation?
Yu.N. Efremov 1,
S. Ehlerová 2 and
J. Palou 2
Received 11 March 1999 / Accepted 13 July 1999
We discuss differences in shapes, expansion velocities and fragmentation times of structures created by an energy deposition from a single Gamma-Ray Burst (GRB) and an OB association to the ISM. After the initial inflation, supershells produced by GRBs are almost static or slowly expanding, contrary to more rapidly expanding supershells created by OB associations. We discuss the position of the energy source relative to the symmetry plane of the galaxy: observed arc-like structures can be the most dense part of structures formed by an expansion from a source above or below the galactic plane. Arcs may also form if the expansion takes place inside a giant HI cloud. We try to reproduce the size, the age, and the average distance between OB associations in the Sextant region at the edge of LMC 4.
Key words: gamma rays: bursts galaxies: star clusters galaxies: individual: LMC ISM: supernova remnants ISM: bubbles stars: formation
Send offprint requests to: J. Palou (firstname.lastname@example.org)
© European Southern Observatory (ESO) 1999
Online publication: October 4, 1999