Multichannel Astrometric Photometer--based Parallaxes of Evolved Stars: chi Cygni, 51 Andromedae, and OP Andromedae
Abstract
Using data from Allegheny Observatory's Thaw/MAP astrometric system, absolute parallaxes are presented for Chi Cygni, 51 Andromedae, the newly discovered RS CVn variable OP Andromedae, and selected stars in these fields. Using existing angular diameter measures and the new parallaxes, linear diameters for Chi Cygni and 51 And are given. Chi Cygni has a perturbation in declination having a period of 0.75 yr and an amplitude of +/- 5 mas. Owing to the extreme variability of Chi Cygni, no further characterization of the system is possible at this time. Other results of spectral interest include the detection of a perturbation in the motion of BD +47 deg 466. This system was found to have a parallax of 14.4 +/- 1.2 mas.
- Publication:
-
The Astrophysical Journal
- Pub Date:
- August 1991
- DOI:
- 10.1086/170394
- Bibcode:
- 1991ApJ...377..669S
- Keywords:
-
- Astrometry;
- Astronomical Photometry;
- Late Stars;
- Stellar Evolution;
- Stellar Motions;
- Stellar Parallax;
- Line Of Sight;
- Stellar Magnitude;
- Variable Stars;
- Astronomy;
- ASTROMETRY;
- STARS: DIAMETERS;
- STARS: LATE-TYPE