Astronomy and Astrophysics – Astrophysics
Scientific paper
Nov 1985
adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=1985apj...298..838f&link_type=abstract
Astrophysical Journal, Part 1 (ISSN 0004-637X), vol. 298, Nov. 15, 1985, p. 838-843.
Astronomy and Astrophysics
Astrophysics
138
Hydrogen, Interstellar Matter, Molecular Clouds, Sodium, Least Squares Method, Signal To Noise Ratios
Scientific paper
From a compilation of interstellar atomic sodium and neutral hydrogen absorption measurements, together with new high signal-to-noise ratio Na I observations and detailed analysis through a profile fitting method, the column-density correlation N(Na I) versus N(H) has been derived. Extending now over more than three orders of magnitude, especially toward low-column density clouds, a slope of unity is found instead of the previous quadratic dependence. Still valid for mean space densities, this new result leads to a deduction that, in the diffuse interstellar medium, the product of the recombination coefficient of Na II and the electron space density, alpha n(e), is nearly constant. The n(e) evaluations are consistent with the three-phase model of the interstellar medium, while at high densities, the shielding of UV photons by dust becomes the dominant factor.
Ferlet Roger
Gry Cecile
Vidal-Madjar Alfred
No associations
LandOfFree
NA I as a tracer of H I in the diffuse interstellar medium 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 NA I as a tracer of H I in the diffuse interstellar medium, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and NA I as a tracer of H I in the diffuse interstellar medium will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-977986