Hipparcos red stars in the HpVT2 and VIC systems

Autor(en)

Imants Platais, Dimitri Pourbaix, Alain Jorissen, Valeri V Makarov, Leonid N. Berdnikov, N N Samus, Tom Lloyd Evans, Thomas Lebzelter, Julius Sperauskas

Abstrakt

For Hipparcos M, S, and C spectral type stars, we provide calibrated instantaneous (epoch) Cousins V - I color indices using newly derived HpVT2 photometry. Three new sets of ground-based Cousins VI data have been obtained for more than 170 carbon and red M giants. These datasets in combination with the published sources of VI photometry served to obtain the calibration curves linking Hipparcos/Tycho Hp - VT2 with the Cousins V - I index. In total, 321 carbon stars and 4464 M- and S-type stars have new V - I indices. The standard error of the mean V - I is about 0.1 mag or better down to Hp ˜ 9 although it deteriorates rapidly at fainter magnitudes. These V - I indices can be used to verify the published Hipparcos V - I color indices. Thus, we have identified a handful of new cases where, instead of the real target, a random field star has been observed. A considerable fraction of the DMSA/C and DMSA/V solutions for red stars appear not to be warranted. Most likely such spurious solutions may originate from usage of a heavily biased color in the astrometric processing.

Organisation(en)

Institut für Astrophysik

Externe Organisation(en)

Johns Hopkins University, Vrije Universiteit Brussel, California Institute of Technology (Caltech), Lomonosov Moscow State University (MSU), Russian Academy of Sciences, University of St. Andrews, Vilnius University (VU)

Journal

Astronomy & Astrophysics

Band

397

Seiten

997-1010

Anzahl der Seiten

14

ISSN

0004-6361

Publikationsdatum

2003

Peer-reviewed

Ja

ÖFOS 2012

103003 Astronomie

Link zum Portal

https://ucrisportal.univie.ac.at/de/publications/44ec2b36-854d-4e2c-8540-0510ca8f09ab