Observation of a very narrow H-alpha feature close to SN 1987A.
Abstract
A high-resolution observation of an H-alpha feature in the vicinity of SN 1987A, which appears as a secondary component at v = 291 km/s in the narrow circumstellar H-alpha emission line, is reported. Its position is 2.1 + or - 0.3 arcsec NW of the supernova, and it is unresolved in this direction, with an upper limit on its radius of about 1 light-year. Its geometry perpendicular to this axis is unknown and could well be extended; e.g., arclike. Its luminosity in H-alpha is 1.6 x 10 to the 34th erg/s, and the spectral FWHM is less than 10 km/s. Several possibilities for its origin are discussed, and it is concluded that the H-alpha feature is connected with the arclike structure apparent on optical images and could be due to a dusty shell within the fossil red-supergiant wind from Sk -69 deg 202.
- Publication:
-
Astronomy and Astrophysics
- Pub Date:
- October 1990
- Bibcode:
- 1990A&A...237...12H
- Keywords:
-
- Emission Spectra;
- H Alpha Line;
- Stellar Envelopes;
- Stellar Radiation;
- Supernova 1987a;
- Stellar Structure;
- Stellar Winds;
- Supergiant Stars;
- Astrophysics