H3+ and other species in the diffuse cloud towards ζ Persei: A new detailed model

Details H3+ and other species in the diffuse cloud towards ζ Persei: A new detailed model H3+ and other species in the diffuse cloud towards ζ Persei: A new detailed model

Apr 2004

adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2004a%26a...417..993l&link_type=abstract

Astronomy and Astrophysics, v.417, p.993-1002 (2004)

Astronomy and Astrophysics

Astrophysics

54

Molecular Processes, Ism: Cosmic Rays, Ism: Abundances, Ism: Molecules, Ism: General

Scientific paper

McCall et al. have recently shown that a large column density for the molecular ion H3+ of ≈8 × 1013 cm-2 exists in the classical diffuse cloud towards ζ Persei. They have used this observation to infer that the cosmic ray ionization rate ζ for this source is approximately 40 times larger than previously assumed. But, although the value of ζ they infer (≈1.2 × 10-15 s-1) can explain the abundance of H3+, it is not at all clear that such a high ionization rate is consistent with the many other detailed atomic and molecular observations made along the same line of sight. In particular, the abundances of the species OH and HD were previously used to determine a much lower ionization rate. In this paper, we report a detailed chemical model of the diffuse cloud towards ζ Persei which appears to fit to a reasonable extent both the older atomic and molecular observations and the new detection of H3+. We consider two phases - a long (4 pc) diffuse region at 60 K and a tiny (≈100 AU) dense region at 20 K, both with an ionization rate ζ in between the standard value and that advocated by McCall et al. The model reproduces almost all abundances, including that of H3+, to within a factor of three or better. To reproduce the CH+ abundance and those of the excited rotational populations of H2, we consider the addition of shocks. This phase has little effect on our calculated abundance for H3+.

Affiliated with

Also associated with

No associations

Rating

H3+ and other species in the diffuse cloud towards ζ Persei: A new detailed model 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 H3+ and other species in the diffuse cloud towards ζ Persei: A new detailed model, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and H3+ and other species in the diffuse cloud towards ζ Persei: A new detailed model will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-1385542