The Interstellar Medium around Galactic WN Stars: WR 2, WR 128, and WR 151

Astronomy and Astrophysics – Astronomy

Scientific paper

Rate now

  [ 0.00 ] – not rated yet Voters 0   Comments 0

Details

21

Ism: Bubbles, Radio Emission Lines, Stars: Individual (Hd 6327, Hd 187282, Cx Cephei), Stars: Wolf-Rayet

Scientific paper

The neutral hydrogen distribution has been studied in the direction of three Galactic Wolf-Rayet (W-R) stars, using the 100 m Effelsberg radio telescope. Neutral hydrogen voids, regions of low H I emissivity, are observed over a 10-16 km s^-1 velocity range for the stars WR 2 (=HD 6327), WR 128 (=HD 187282), and WR 151 (=CX Cep). These minima are interpreted as the observable 21 cm counterpart of the interstellar bubble created by the powerful winds of W-R stars and their progenitors. The H I cavities are elongated structures having an axial ratio ranging from 1.3 (WR 151) to 2.0 (WR 128). As pointed out in previous studies, the W-R stars are always off-center with respect to either the geometric center of the H I void or the absolute minimum inside the cavity. This offset ranges from 40% to 70% of the H I hole's minor axis. The major axes of these cavities are ~30 pc for both WR 2 and WR 128, and ~50 pc for WR 151. The missing H I mass amounts to 96 M_solar (WR 128), 200 M_solar (WR 2), and 480 M_solar (WR 151). Some of the physical parameters of the ring nebula associated with WR 128, such as its expansion velocity, 80+/-22 km s^-1, radius, 6.3+/-0.2 pc, and characteristic age, (7.4+/-2.4)x10^4 yr, are derived from a simple geometric model that accounts for the discrepancy between the radial velocity of the H I hole and the ring nebula related to WR 128.

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

The Interstellar Medium around Galactic WN Stars: WR 2, WR 128, and WR 151 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 Interstellar Medium around Galactic WN Stars: WR 2, WR 128, and WR 151, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and The Interstellar Medium around Galactic WN Stars: WR 2, WR 128, and WR 151 will most certainly appreciate the feedback.

Rate now

     

Profile ID: LFWR-SCP-O-1082946

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