Carbon Monoxide and Molecular Hydrogen Column Densities, and Total Mass of the Taurus Molecular Cloud

Details Carbon Monoxide and Molecular Hydrogen Column Densities, and Total Mass of the Taurus Molecular Cloud Carbon Monoxide and Molecular Hydrogen Column Densities, and Total Mass of the Taurus Molecular Cloud

Dec 2007

adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2007aas...211.1202g&link_type=abstract

American Astronomical Society, AAS Meeting #211, #12.02; Bulletin of the American Astronomical Society, Vol. 39, p.750

Astronomy and Astrophysics

Astronomy

1

Scientific paper

We describe some of the key results of a large-scale mapping survey of the Taurus molecular cloud, carried out in 12CO and 13CO J = 1-0 using the FRCAO 14m telescope. We Nyquist sampled a hundred square degree area , resulting in 3 million pixel spectral line images. The SEQUOIA 32-element focal plane array was used in an on-the-fly mapping mode giving mean rms antenna temperatures of 0.125 K for 13CO and 0.28K for 12CO. Using the data on the two isotopologues, we have derived the column density distribution. In the high extinction regions, both species are detected in each pixel and it is relatively straightforward to derive the CO column density. In regions of lower extinction, comprising approximately one third of area mapped, we detect the 12CO but not the 13CO in individual pixels. We bin the data by excitation temperature (derived from 12CO alone). Averaging the many pixels within each bin, we easily detect the 13CO. Using an LVG model for radiative transfer, we derive for each range of 12CO excitation temperature the molecular hydrogen space density and the carbon monoxide column density. We handle the portion of the map in which we do not detect either isotopologue in individual pixels in a similar manner, but treat it as a single entity. The hydrogen density is a few hundred per cubic centimeter in the low extinction portion of the cloud. Using the model of van Dishoeck and Black (1988) to convert the carbon monoxide to molecular hydrogen column density, we find that the total mass of the region mapped is 23,000 solar masses, several times larger than previously had been obtained considering only the higher extinction portion of Taurus, but in good agreement with that expected from the standard 12CO luminosity to mass conversion factor.

Affiliated with

Also associated with

No associations

Rating

Carbon Monoxide and Molecular Hydrogen Column Densities, and Total Mass of the Taurus Molecular Cloud 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 Carbon Monoxide and Molecular Hydrogen Column Densities, and Total Mass of the Taurus Molecular Cloud, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Carbon Monoxide and Molecular Hydrogen Column Densities, and Total Mass of the Taurus Molecular Cloud will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-1474671