Runaway expansion of giant shells driven by radiation pressure from field stars

Abstract

view Abstract Citations (47) References (24) Co-Reads Similar Papers Volume Content Graphics Metrics Export Citation NASA/ADS Runaway expansion of giant shells driven by radiation pressure from field stars Elmegreen, B. G. ; Chiang, W. -H. Abstract Radiation pressure from field stars can exert an outward force on a large shell of gas and dust in the interstellar medium. This radiative force increases with increasing shell size, so a sufficiently large shell can expand at an ever-increasing speed up to a kiloparsec or more in size. The supershells that are observed in our Galaxy and in other galaxies could have originated as smaller shells around OB associations or star complexes and then have grown to their kiloparsec sizes by radiation pressure from background starlight. The formation times for such supershells are between 50 and 100 million years, so the OB associations that initially triggered their growth may not be visible anymore. Background starlight alone can give a giant shell a kinetic energy of 10 to the 51st ergs or more. Publication: The Astrophysical Journal Pub Date: February 1982 DOI: 10.1086/159667 Bibcode: 1982ApJ...253..666E Keywords: B Stars; Interstellar Matter; Nebulae; O Stars; Radiation Pressure; Star Distribution; Stellar Envelopes; Absorptivity; Equations Of Motion; Kinetic Energy; Radiant Flux Density; Stellar Evolution; Astrophysics full text sources ADS |