Geneva Paper Abstracts

Cramer N., Maeder A. (1979, A&A 78, 305)


Based on colour differences measuring the Balmer jump, but with different sensitivity to the accumulated effets of hydrogen and H- and K-lines, a method of luminosity and Teff calibration for B-type stars is established in the Geneva system. The references for calibration rest on star cluster distances properly adjusted to the Hyades modulus and on Code's et al. (1976) effective temperatures based on measurements of angular stellar diameters and absolute UV, visible and IR fluxes. The calibration is essentially independent of interstellar reddening and it allows a clear recognition of stellar perculiarities. The effects of unresolved binaries and rotation are also considered and a comparison with uvby beta results is made.

Kobi D., North P. (1990, A&AS 85, 999)


A new, semi-empirical calibration of the d, m2 and B2-V1 parameters of Geneva photometry is given, which allows to estimate Te, log g and [Fe/H] of A4 V-III to G5 V stars. The calibration is based on Kurucz's grid of atmosphere models, corrected by means of fundamental stars. Recent evolutionary tracks for stars witgh a metal content Z = 0.02 are used to calibrate the d vs B2-V1 diagram in term of mass for solar-composition stars.

North P., Nicolet B. (1990, AA 228, 78)


A new, semi-empirical calibration of the two reddening free parameters X and Y of Geneva photometry in terms of effective temperature and gravity is proposed. The calibration is based on Kurucz's grid of atmosphere models and on a set of fundamental stars; it is valid for main sequence stars with Te > 10'000K. Theoretical evolutionary tracks were then used to calibrate the Y vs X diagram in terms of stellar mass, for M > 2.5-3.0 M.
Last update: 7 Novembre 1995