Astronomy and Astrophysics – Astrophysics
Scientific paper
Jan 2011
adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2011a%26a...525a.116g&link_type=abstract
Astronomy and Astrophysics, Volume 525, id.A116
Astronomy and Astrophysics
Astrophysics
5
Ism: Clouds, Ism: Molecules
Scientific paper
Using the IRAM 30 m telescope we observed molecular absorption lines from CCH and c-C3H2 produced by diffuse and translucent clouds along the lines of sight towards massive star forming regions. The same sources are surveyed with Herschel/HIFI as part of the PRISMAS guaranteed time program, for molecular absorption lines due to hydrides and carbon clusters. The background sources are massive star-forming regions (G34.3 + 0.1, G10.62-0.39, W51, W49N) and SgrA*. The line profiles of the CCH, and c-C3H2, are strikingly similar for all lines of sight, showing that the ratio of the opacities of the probed transitions, (JK_a, K_c = 21,2-10,1) for c-C3H2, and (J = 1-0, F = 5/2-3/2) for CCH, is nearly constant along all lines of sight, at τ_CCH ~ 1.8 × τ_c-C_3H_2. As a consequence, the ratio of the column densities of CCH and c-C3H2 is nearly constant and similar to the value derived earlier for diffuse clouds detected along lines of sight towards extragalactic continuum sources, N(CCH) = (28 ± 1.4) N(c-C3H2) (Lucas & Liszt 2000, A&A, 358, 1069). PDR models are able to reproduce the observed CCH, column densities for the range of physical conditions appropriate for the absorbing matter (n = 100-3000 cm-3; AV = 1-5 mag) but can neither fit the observed c-C3H2,column densities nor the tight correlation between CCH, and c-C3H2.
Based on observations obtained with the IRAM 30 m telescope.
de Luca Massimo
Falgarone Edith
Gerin Maryvonne
Godard Benjamin
Hily-Blant Pierre
No associations
LandOfFree
The tight correlation of CCH, and c-C3H2 in diffuse and translucent 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 tight correlation of CCH, and c-C3H2 in diffuse and translucent clouds, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and The tight correlation of CCH, and c-C3H2 in diffuse and translucent clouds will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-1392945