Radio recombination lines from high emission measure nebulae

Details Radio recombination lines from high emission measure nebulae Radio recombination lines from high emission measure nebulae

May 1982

adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=1982apj...256..543l&link_type=abstract

Astrophysical Journal, Part 1, vol. 256, May 15, 1982, p. 543-549.

Astronomy and Astrophysics

Astronomy

1

Abundance, H Lines, Helium, Hydrogen Recombinations, Nebulae, Radio Sources (Astronomy), Absorptivity, Emission Spectra, H Ii Regions, High Frequencies, Optical Thickness, Planetary Nebulae, Spectral Line Width

Scientific paper

High frequency radio recombination lines from high emission measure nebulae, like the compact components of H II regions and perhaps some planetary nebulae, may have optical depths that approach -1. Under these circumstances, the hydrogen line peak will be enhanced, and its line width will narrow. Recombination lines from other species, like helium, have smaller optical depth and are not amplified as strongly. Thus, at high frequencies, the apparent helium abundance from a bright, compact nebula can appear anomalously low. This phenomenon might contribute to the low apparent helium abundances in Sgr B2, W3(OH), and DR 21.

Affiliated with

Also associated with

No associations

Rating

Radio recombination lines from high emission measure nebulae 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 Radio recombination lines from high emission measure nebulae, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Radio recombination lines from high emission measure nebulae will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-1100466