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On-line determination of stellar atmospheric parameters Teff, log g, [Fe/H] from ELODIE echelle spectra. II. The library of F5 to K7 stars
Soubiran, C.; Katz, D.; Cayrel, R.
A library of 211 echelle spectra taken with ELODIE at the Observatoire de Haute-Provence is presented. It provides a set of spectroscopic standards covering the full range of gravities and metallicities in the effective temperature interval [4000 K, 6300 K]. The spectra are straightened, wavelength calibrated, cleaned of cosmic ray hits, bad pixel…
The art of fitting p-mode spectra. I. Maximum likelihood estimation
Appourchaux, T.; Gizon, L.; Rabello-Soares, M. -C.
In this article we present our state of the art of fitting helioseismic p-mode spectra. We give a step by step recipe for fitting the spectra: statistics of the spectra both for spatially unresolved and resolved data, the use of Maximum Likelihood estimates, the statistics of the p-mode parameters, the use of Monte-Carlo simulation and the signifi…
On the use of the HIPPARCOS intermediate astrometric data
Evans, D. W.; van Leeuwen, F.
With the publication of the Hipparcos catalogue, astrometric data of unprecedented quality and quantity has become available, providing parallaxes, positions and proper motions free from systematic errors down to a level of at least 0.1 mas and 0.1 mas y(-1) . The Hipparcos catalogue, however, contains not only these ``ready-to-use'' positions, pa…
Mass determination of astrometric binaries with Hipparcos. III. New results for 28 systems
Mignard, F.; Martin, C.; McAlister, H. A. +1 more
This paper is the third of a series devoted to the determination of stellar masses from Hipparcos data. This is a continuation of Martin et al. (1997), who introduced the theory and assessed the performance of the method from simulated data, and of a second paper with the first results for 46 systems, ( te[Martin & Mignard 1998]{Mar98}). The o…
Long-term monitoring of active stars. VIII. UBV(RI)_(c) photometry collected in February 1992
Cutispoto, G.
As a part of an extensive program focusing on the global properties and evolution of active stars, high-precision UBV(RI)_c photometry of 31 selected stars, collected at the European Southern Observatory over the 14-29 February 1992 interval, is presented. Significant evolution of the light curves, period variations and evidence for long-term vari…
HIPPARCOS photometry of 24 variable massive stars (alpha Cygni variables)
van Leeuwen, F.; van Genderen, A. M.; Zegelaar, I.
The photometric variability of 24 alpha Cyg variables, i.e. variable super-and hypergiants, observed by the Hipparcos satellite is described. Three of the selected stars are situated in the SMC, 12 in the LMC and the remaining 9 in the Galactic plane. Four of them are hot S Dor-type variables, or LBVs (luminous blue variables) and two are possible…
New variable chemically peculiar stars identified in the HIPPARCOS archive
Paunzen, E.; Maitzen, H. M.
Since variability of chemically peculiar (CP) stars plays an important role for the astrophysical explanation of their outstanding behaviour, we have identified new variable CP stars listed in Renson's catalogue using the extensive Hipparcos Variability Annex. From the 293 objects found, 33 were excluded because they are no CP stars and/or have no…
On the HIPPARCOS photometry of chemically peculiar B, A, and F stars
Adelman, Saul J.
The Hipparcos photometry of the Chemically Peculiar main sequence B, A, and F stars is examined for variability. Some non-magnetic CP stars, Mercury-Manganese and metallic-line stars, which according to canonical wisdom should not be variable, may be variable and are identified for further study. Some potentially important magnetic CP stars are no…
Infrared standards for ISO. I. A new calibration of mid infrared photometry
Kessler, M. F.; Bouchet, P.; Metcalfe, L. +5 more
We present N, 8.7 mu m, 9.8 mu m 12.5 mu m and Q bolometry of 26 stars which were observed on the IRTF. These are primarily K giants which have been well measured at other wavelengths and are chosen to be single and non-variable. Hence the data presented provides a new homogeneous set of mid IR standards. As a test of part of the calibration strat…
Spectral decomposition by genetic forward modelling
Judge, P. G.; Brown, J. C.; Charbonneau, P. +3 more
We discuss the analysis of real and simulated line spectra using a genetic forward modelling technique. We show that this Genetic Algorithm (GA) based technique experiences none of the user bias or systematic problems that arise when faced with poorly sampled or noisy data. An important feature of this technique is the ease with which rigid a prio…