The expansion of the outer circumstellar shell of P Cygni
Abstract
The expansion of a faint, outer irregular shell to the circumstellar nebulosity of the luminous blue variable PCygni has been measured with the Manchester Echelle Spectrometer combined with the high-altitude San Pedro Martir 2.1-m UNAM telescope. This is the first ever measurement of the expansion velocity of such a historic remnant of a luminous blue variable star eruption. The faintness of the outer shell and the high brightness and close proximity of the star make it a particularly difficult observation. The high optical luminosity of the spectrometer and the clarity of the sky have combined to permit a successful measurement. A radial expansion velocity of 185+/-10 km s^-1 is implied, which suggests an age of 2100+/-200 yr for this 1.6 arcmin diameter outer shell, if we assume a distance of 1.8 kpc to PCygni.
- Publication:
-
Monthly Notices of the Royal Astronomical Society
- Pub Date:
- December 1996
- DOI:
- 10.1093/mnras/283.3.L69
- Bibcode:
- 1996MNRAS.283L..69M
- Keywords:
-
- LINE: PROFILES;
- CIRCUMSTELLAR MATTER;
- STARS: INDIVIDUAL: PCYGNI;
- STARS: MASS-LOSS;
- ISM: BUBBLES