The conductivity of dense molecular gas

Astronomy and Astrophysics – Astrophysics

Scientific paper

Rate now

  [ 0.00 ] – not rated yet Voters 0   Comments 0

Details

MNRAS accepted; 9 pp incl 8 figs, LaTeX, uses epsf.sty mn.sty

Scientific paper

10.1046/j.1365-8711.1999.02211.x

We evaluate the conductivity tensor for molecular gas at densities ranging from 10^4 to 10^15 cm^-3 for a variety of grain models. The Hall contribution to the conductivity has generally been neglected in treatments of the dynamics of molecular gas. We find that it is not important if only 0.1 micron grains are considered, but for a Mathis-Rumpl-Nordsieck grain-size distribution (with or without PAHs) it becomes important for densities between 10^7 and 10^11 cm^-3. If PAHs are included, this range is reduced to 10^9 -- 10^10 cm^-3. The consequences for the magnetic field evolution and dynamics of dense molecular gas are profound. To illustrate this, we consider the propagation of Alfven waves under these conditions. A linear analysis yields a dispersion relation valid for frequencies below the neutral collision frequencies of the charged species. The dispersion relation shows that there is a pair of circularly polarised modes with distinct propagation speeds and damping rates. We note that the gravitational collapse of dense cloud cores may be substantially modified by the Hall term.

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 conductivity of dense molecular gas 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 conductivity of dense molecular gas, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and The conductivity of dense molecular gas will most certainly appreciate the feedback.

Rate now

     

Profile ID: LFWR-SCP-O-17387

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