A multi-wavelength study of the Sharpless 151 region

Details A multi-wavelength study of the Sharpless 151 region A multi-wavelength study of the Sharpless 151 region

Sep 1998

adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=1998a%26a...337..539b&link_type=abstract

Astronomy and Astrophysics, v.337, p.539-557 (1998)

Astronomy and Astrophysics

Astrophysics

13

Ism: Clouds, Ism: Molecules, Radio Lines: Ism, Ism: Individual Objects: Sh 2-151

Scientific paper

Results are presented of an extensive, multi-wavelength study of the area around the evolved HII region Sh 2-151. We discuss the excitation of the HII region, and analyze its interaction with molecular clouds in the vicinity, the clouds themselves, and their embedded objects. We present KOSMA 3-m (12) CO(2-1) and (3-2) observations of a 26(') x46(') region around Sh 2-151. These observations reveal five clouds, with a total mass of 2.9x10(4) Msun. A small (2(') x4(') ) region to the SW of Sh 2-151 was mapped in several CO and CS transitions with the IRAM 30-m telescope. The latter region contains 1.8x 10(3) Msun of molecular mass, and hosts an IRAS- and H_2O maser source (WB89-234). Tracers of higher (column-) densities, such as C(18) O and CS, show the existence of two clumps (N(H_2) \approxprox 1-2 x 10(22) cm(-2) ) connected by a ridge of warm (Tkin ~ 36 K) narrow-line (Delta v((12) CO)<1 km s(-1) ) gas. The southern clump contains the IRAS/maser source, exhibits a molecular outflow (M$~prox5 M_{\odot}, \taudyn ~prox 2\times 10^5 yr), and is therefore probably a region of active star formation. In the northern clump the line profiles have an intermediate width (1-3 km s^{-1}; partly due to the presence of two emission components) and are non-gaussian (shoulders, wings) at several positions. IRAS (HIRES) observations show there is also FIR emission associated with the northern clump. NIR (J, H, K, H_2) observations show the presence of several red star-like objects and diffuse emission in both clumps; some of the diffuse emission is stronger and more extended in K and H_2, and may be due to dust emission around embedded objects. HIRES data reveal that IRAS23004+5642 (WB89-234) nearly coincides with the H_2O maser and the outflow, and not with the strong, narrow-line CO-emitting gas detected towards the point source catalog position. The linewidth of this relatively low-density warm gas, the heating source of which is as yet unknown, indicates the absence of dynamical interaction with both Sh 2-151 and the embedded IR sources. >From the HIRES 60\mum and 100\mum data we derive dust temperatures of 30-40 K, the highest values occurring near the maser, and a dust mass of \sim30 M_{\odot}; assuming a gas-to-dust ratio of 100, this implies we detect \sim10% of the dust. Evidence from the available (literature) data leads to the conclusion that the exciting star(s) of Sh 2-151 has (have) not yet been identified. We suspect that one or more early type (

Affiliated with

Also associated with

No associations

Rating

A multi-wavelength study of the Sharpless 151 region 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 A multi-wavelength study of the Sharpless 151 region, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and A multi-wavelength study of the Sharpless 151 region will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-810164