Distances to nearby molecular clouds and star forming regions.III. Localizing extinction jumps with a Hipparcos calibration of 2mass photometry

Astronomy and Astrophysics – Astrophysics – Galaxy Astrophysics

Scientific paper

Rate now

  [ 0.00 ] – not rated yet Voters 0   Comments 0

Details

Scientific paper

We want to estimate the distance to molecular clouds in the solar vicinity in a statistically precise way. Clouds are recognized as extinction discontinuities. The extinction is estimated from the $(H-K) \ vs. \ (J-H)$ diagram and distances from a $(J-K)_0 \ vs. \ M_J$ relation based on Hipparcos. The stellar sample of relevance for the cloud distance is confined by the FWHM of the $A_V / D_{\star}(pc)$ or of its derivative. The cloud distance is estimated from fitting a function to the $(A_V, 1/ \pi_{JHK})$ pairs in this sample with a function like $arctanh^p (D_\star /D_{cloud})$ where the power $p$ and $D_{cloud}$ both are estimated. The fit follows the $(A_V, 1/\pi_{JHK})_{cloud}$ data rather well. Formal standard deviations less than a few times 10 pc seem obtainable implying that cloud distances are estimated on the $\lesssim$10$\%$ level. Such a precision allows estimates of the depths of cloud complexes in some cases. As examples of our results we present distances for $\sim$25 molecular clouds in Table ~\ref{t2}. $Keywords$: interstellar medium: molecular cloud distances

No associations

LandOfFree

Say what you really think

Search LandOfFree.com for scientists and scientific papers. Rate them and share your experience with other people.

Rating

Distances to nearby molecular clouds and star forming regions.III. Localizing extinction jumps with a Hipparcos calibration of 2mass photometry 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 Distances to nearby molecular clouds and star forming regions.III. Localizing extinction jumps with a Hipparcos calibration of 2mass photometry, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Distances to nearby molecular clouds and star forming regions.III. Localizing extinction jumps with a Hipparcos calibration of 2mass photometry will most certainly appreciate the feedback.

Rate now

     

Profile ID: LFWR-SCP-O-260543

  Search
All data on this website is collected from public sources. Our data reflects the most accurate information available at the time of publication.