A deep VLA search for OH (1612 MHz) maser sources in the galactic plane.
Abstract
The results of a VLA OH (1612 MHz) search for OH/IR stars in 7 fields along the galactic plane are presented. Forty-four sources were detected of which 35 were not previously known. It is shown that "blind" radio interferometric observations (such as with the VLA) are capable of filling up the gap in the IRAS based OH surveys near the galactic plane. This is important for the dynamical modelling of the disc and bulge of our Galaxy. It is also demonstrated that the high resolution of a synthesis telescope is needed to avoid confusion in the galactic plane. Most detected sources are likely to be young (<~1Gyr) and massive (M_ms_>2-3Msun_) evolved stars and have high expansion velocities (v_exp_>14.5km/s) and small deviations (<10km/s) from galactic rotation. Like Baud et al. (1981) we find a peak in the number of sources around l=25deg, a region associated with active star formation and a low number of stars at l=5deg and 10deg.
- Publication:
-
Astronomy and Astrophysics
- Pub Date:
- July 1994
- Bibcode:
- 1994A&A...287..479B
- Keywords:
-
- Asymptotic Giant Branch Stars;
- Interstellar Masers;
- Milky Way Galaxy;
- Radio Astronomy;
- Radio Observation;
- Radio Sources (Astronomy);
- Very Large Array (Vla);
- Astronomical Interferometry;
- Infrared Astronomy Satellite;
- Radio Spectra;
- Sky Surveys (Astronomy);
- Star Distribution;
- Velocity Distribution;
- Astronomy;
- STARS: AGB;
- POST-AGB;
- TECHNIQUES: INTERFEROMETRIC;
- MASERS;
- SURVEYS;
- RADIO LINES: STARS