Open AccessUBV ( RI ) C photometry of Hipparcos red stars
Author(s) -
Koen C.,
Kilkenny D.,
Van Wyk F.,
Cooper D.,
Marang F.
Publication year - 2002
Publication title -
monthly notices of the royal astronomical society
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.058
H-Index - 383
eISSN - 1365-2966
pISSN - 0035-8711
DOI - 10.1046/j.1365-8711.2002.05403.x
Subject(s) - physics , photometry (optics) , stars , astrophysics , absolute magnitude , astronomy , apparent magnitude , homogeneous , thermodynamics
We present homogeneous and standardized UBV ( RI ) C photometry for nearly 550 M stars selected from the Hipparcos satellite data base using the following selection criteria: lack of obvious variability (no Hipparcos variability flag); δ <+10°; ( V ‐ I )>1.7; and V magnitude fainter than about 7.6. Comparisons are made between the current photometry, other ground‐based data sets and Hipparcos photometry. We use linear discriminant analysis to determine a luminosity segregation criterion for late‐type stars, and principal component analysis to study the statistical structure of the colour indices and to calibrate absolute magnitude in terms of ( V ‐ I ) for the dwarf stars. Various methods are used to determine the mean absolute magnitude of the giant stars. We find 10 dwarf stars, apparently previously unrecognized (prior to Hipparcos ) as being within 25 pc, including five within 20 pc.