High-resolution observations of bipolar mass flow from the symbiotic star HM Sagittae.
Abstract
Coudé observations of high spectral and high spatial resolution of the [N II] and [O III] emission lines from HM Sge obtained at various position angles of the spectrograph entrance slit are presented. They reveal bipolar mass flow (≈200 km s-1) collimated into two narrow lobes separated by 1arcsec.5, two low-velocity features of 0arcsec.2 separation within the equatorial plane compatible with slowly expanding (≈25 km s-1) blobs or a rotating (≈10 km s-1) ring, and a shell of about 0arcsec.5 diameter expanding at an intermediate velocity (≈60 km s-1). A distance of ≈400 pc is inferred from the expansion rate of the nebula. The geometric and kinematical structure of HM Sge seems less compatible with a single-star model for symbiotic stars, but is found in excellent agreement with the model of a binary consisting of a mass-losing M-type giant and a compact companion accreting part of the mass from the giant through an accretion disk.
- Publication:
-
Astronomy and Astrophysics
- Pub Date:
- October 1984
- Bibcode:
- 1984A&A...139..296S
- Keywords:
-
- Stellar Mass Ejection;
- Stellar Spectra;
- Symbiotic Stars;
- Distance;
- Stellar Envelopes;
- Stellar Evolution;
- Stellar Luminosity;
- Stellar Mass;
- Astronomy