Supershells and propagating star formation

Journal Article · Mon Jun 01 04:00:00 EDT 1987 · Astrophys. J.; (United States)

DOI:https://doi.org/10.1086/165267· OSTI ID:6148212

Mccray, R; Kafatos, M

Stellar winds and repeated supernovae from an OB association will create a cavity of coronal gas in the interstellar medium, with radius greater than 100 pc, surrounded by a dense, expanding shell of cool interstellar gas. If the association has a typical initial mass function, its supernovae explosions will inject energy into the supershell at a nearly constant rate for about 50 Myr. The supershell loses its interior pressure and enters the snowplow phase when radiative cooling becomes important or when the shell bursts through the gas disk of a galaxy, typically after a few times 10 Myr and with a radius of 100-300 pc. At approximately the same time, the supershell becomes gravitationally unstable, forming giant molecular clouds which are sites for new star formation. There is widespread evidence for supershells in the Galaxy and other spiral and irregular galaxies from 21-cm emission-line surveys, optical emission-line surveys, and studies of supernova remnants. The gravitational instability of the supershells provides a physical mechanism for induced star formation and may account for bursts of star formation, especially in irregular galaxies. 85 references.

• Research Organization: Joint Institute for Lab. Astrophysics, Boulder, CO; George Mason Univ., Fairfax, VA
• OSTI ID: 6148212
• Journal Information: Astrophys. J.; (United States), Journal Name: Astrophys. J.; (United States) Vol. 317; ISSN ASJOA
• Country of Publication: United States
• Language: English

Related Subjects

640102* -- Astrophysics & Cosmology-- Stars & Quasi-Stellar
Radio & X-Ray Sources
71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
COOLING
COSMIC GASES
ERUPTIVE VARIABLE STARS
FLUIDS
GALAXIES
GASES
INTERSTELLAR SPACE
MASS
MASS TRANSFER
MILKY WAY
RADIATIVE COOLING
SPACE
STAR CLUSTERS
STAR EVOLUTION
STARS
STELLAR ACTIVITY
STELLAR WINDS
SUPERNOVAE
VARIABLE STARS