The photoevaporation of interstellar clouds. II - Equilibrium cometary clouds

Astronomy and Astrophysics – Astrophysics

Scientific paper

Rate now

  [ 0.00 ] – not rated yet Voters 0   Comments 0

Details

198

Comets, H Ii Regions, Interstellar Magnetic Fields, Interstellar Matter, Nebulae, Star Formation, Astronomical Models, Continuous Radiation, Early Stars, Gravitational Effects, Stellar Evolution

Scientific paper

An approximate analytic theory for the evolution of an interstellar cloud which is exposed to the ionizing radiation of a newly formed star is developed. This paper will follow the evolution of a photoevaporating cloud beyond its initial radiation-driven implosion. Under the realistic assumption of axisymmetry, the imploded cloud is shown to assume a steady, cometary shaped configuration in which the embracing ionization front balances the pressure of the neutral gas. The steady cloud configuration is determined solely by the cloud mass, the incident Lyman continuum flux, and the adiabatic index of the gas. Because of the rocket effect of the evaporating gas, the cloud is accelerated away from the ionizing star. Over a wide range of parameters, the cloud shape, its mass-loss rate, lifetime, and acceleration are computed. The characteristic rocket velocity is typically 10 km/s, but can be as low as 5 km/s, which is significantly lower than previous estimates. Magnetic fields are taken into account in an approximate way and are shown to be a significant factor for the cloud pressure support and gravitational stability. The theory is applied to the photoevaporating globules in the Rosette and Gum Nebulae.

No associations

LandOfFree

Say what you really think

Search LandOfFree.com for scientists and scientific papers. Rate them and share your experience with other people.

Rating

The photoevaporation of interstellar clouds. II - Equilibrium cometary clouds does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with The photoevaporation of interstellar clouds. II - Equilibrium cometary clouds, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and The photoevaporation of interstellar clouds. II - Equilibrium cometary clouds will most certainly appreciate the feedback.

Rate now

     

Profile ID: LFWR-SCP-O-779620

  Search
All data on this website is collected from public sources. Our data reflects the most accurate information available at the time of publication.