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Strömgren and Hβ photometry of O and B type stars in star-forming regions - III. Carina Spiral Feature

Strömgren and Hβ photometry of O and B type stars, generally brighter than 9.5 mag is reported for the field of the Carina Spiral Feature. The observations are based on the PPM catalogue identifications and are designed to improve the completeness of the existing data for the bright early-type stars in the field. We present new uvby photometry for 283 stars and Hβ photometry for...

Four-colour photometry of eclipsing binaries - XXXIX. Light curves of the pre–main sequence triple system TY Coronae Australis

Complete uvby light curves of the detached Herbig Be eclipsing binary TY Coronae Australis are presented. A total of 1789 photometric measurements in each of the four colours were obtained in 1989 and in 1992-1994. A detailed analysis of the y light curve obtained in 1992-1993 is published separately (Casey et al. 1997). The reflection nebula around the system contributes about...

Four-colour photometry of eclipsing binaries - XXXVIII. Light curves of the triple system V906 Scorpii

Complete uvby light curves of the detached triple-lined late B-type eclipsing binary V906 Scorpii, secured from 1987 to 1991, are presented. A detailed photometric analysis based on these observations and on new spectroscopic material yields accurate masses and radii (errors ≲2%) for the components, confirms that the system is a member of NGC 6475 (Messier 7), and is published...

Four-colour photometry of eclipsing binaries - XXXVI. Light curves of the O7V+O9V system V 3903 Sagittarii

Complete uvby light curves of the young detached double-lined massive O-type eclipsing binary V 3903 Sagittarii, obtained from 1989 to 1994, are presented. The observations were obtained at two different sites and a discussion of the characteristics of both data sets is included.

Absolute dimensions of solar-type eclipsing binaries - EF Aquarii: a G0 test for stellar evolution models

Context. Recent studies have shown that stellar chromospheric activity, and its effect on convective energy transport in the envelope, is most likely the cause of significant radius and temperature discrepancies between theoretical evolution models and observations. Accurate mass, radius, and abundance determinations from solar-type binaries exhibiting various levels of activity...

A new standard: age and distance for the open cluster NGC 6791 from the eclipsing binary member V20

Context. We wish to determine accurate ages for open clusters and use this, in conjunction with colour–magnitude diagrams, to constrain models of stellar structure and evolution.Aims. The detached eclipsing binary V20 in the old, metal-rich ( = +0.40) open cluster NGC 6791 is studied in order to determine highly accurate masses and radii of its components. This allows the cluster...

Absolute dimensions of eclipsing binaries - XXVII. V1130 Tauri: a metal-weak F-type system, perhaps with preference for Y = 0.23–0.24

Context. Double-lined, detached eclipsing binaries are our main source for accurate stellar masses and radii. This paper is the first in a series with focus on the upper half of the main-sequence band and tests of 1–2  evolutionary models. Aims. We aim to determine absolute dimensions and abundances for the detached eclipsing binary V1130 Tau, and to perform a detailed comparison...

Absolute dimensions of eclipsing binaries. XXVI. - Setting a new standard: Masses, radii, and abundances for the F-type systems AD Bootis, VZ Hydrae, and WZ Ophiuchi

Massachusetts and the Infrared Processing and Analysis Center/ California Institute of Technology, funded by the National Aeronautics and Space Administration and the National Science Foundation. J. V. Clausen

Eclipsing binaries in the Magellanic Clouds - uvby CCD light curves and photometric analyses for HV 982 (LMC), HV 12578 (LMC), HV 1433 (SMC), and HV 11284 (SMC)

We present new accurate CCD uvby light curves for the LMC eclipsing binaries HV 982 and HV 12578, and for the SMC systems HV 1433 and HV 11284 obtained at the Danish 1.5 m telescope at ESO, La Silla. The light curves were derived from DoPHOT photometry, and typical accuracies are between 0.007 and 0.012 mag per point. Standard uvby indices have also been established for each...

Absolute dimensions of solar-type eclipsing binaries. - I. light curves for HS Aqr, KX Aqr, AL Ari, V963 Cen, MR Del, NY Hya, DU Leo, UW LMi, and V358 Pup

We present complete uvby light curves of 9 recently discovered eclipsing binaries having late F, G, and K type components within or near the main-sequence band. They are the first results from a long term program carried out since 1994 at the Strömgren Automatic Telescope at ESO, La Silla. The aim is to provide the accurate absolute dimensions for solar-type stars needed for...

Strömgren and Hβ photometry of O and B type stars in star-forming regions - III. Carina Spiral Feature

Strömgren and Hβ photometry of O and B type stars, generally brighter than 9.5 mag is reported for the field of the Carina Spiral Feature. The observations are based on the PPM catalogue identifications and are designed to improve the completeness of the existing data for the bright early-type stars in the field. We present new uvby photometry for 283 stars and Hβ photometry for...

The eclipsing double-lined binaries V883 Cen and η Mus*

We derive the orbital period and monitor in detail the eclipses of two deep-southern double-lined eclipsing binaries of considerable interest. We present new uvby photometry over more than 100 nights for V883 Cen, scan for the first time the eclipses of η Mus and analyse the data for these two systems together with earlier published photometry. We also add information from high...

Secondary standard stars for CCD photometry

Accurate standard uvby indices are presented for 73 southern B, A, F and G stars in the V magnitude range 8.2 to 10.9. They cover all three transformation regions of the uvby system (Olsen 1983) well. Standard β indices are included for the 55 B, A, and F stars in the sample. Our results provide a useful set of secondary standards for CCD photometry with southern hemisphere 1-2 m...

The CORALIE survey for southern extra-solar planets - IX. A 1.3-day period brown dwarf disguised as a planet

In this article we present the case of HD 41004 AB, a system composed of a K0V star and a 3.7-mag fainter M-dwarf companion. We have obtained 86 CORALIE spectra of this system with the goal of obtaining precise radial-velocity measurements. Since HD 41004 A and B are separated by only 0.5´´, in every spectrum taken for the radial-velocity measurement, we are observing the blended...

Four-colour photometry of eclipsing binaries - XXXVIII. Light curves of the triple system V906 Scorpii

Complete uvby light curves of the detached triple-lined late B-type eclipsing binary V906 Scorpii, secured from 1987 to 1991, are presented. A detailed photometric analysis based on these observations and on new spectroscopic material yields accurate masses and radii (errors ≲2%) for the components, confirms that the system is a member of NGC 6475 (Messier 7), and is published...

Eclipsing binaries in the Magellanic Clouds – II. Absolute dimensions and distance modulus for HV 5936 in the Large Magellanic Cloud⋆

Absolute dimensions and the distance modulus have been established for the early-type eclipsing binary HV 5936 in the LMC. Analyses of new radial velocities, reported here, and CCD light curves published by Jensen, Clausen & Giménez yield masses of $7.2 \pm 0.9\enspace \text {and} \enspace 3.3 \pm 0.5 \enspace \text M_{\odot}$ for the primary and secondary components respectively...

The HARPS search for southern extra-solar planets - VII. A very hot Jupiter orbiting HD 212301

We report the discovery of a planetary companion orbiting the F8V star HD 212301. This is the first “very hot Jupiter” discovered by a radial velocity survey. The detection was made possible by the HARPS spectrograph installed at the ESO 3.6 m telescope in Cerro La Silla, Chile. The data were carefully analyzed to exclude activity induced effects on the measured radial velocities...

Eclipsing binaries in the Magellanic Clouds – I. Absolute dimensions and distance modulus for HV 2226 in the Small Magellanic Cloud⋆

Absolute dimensions and the distance modulus have been established for the early-type eclipsing binary HV 2226 in the SMC. Analyses of the new radial velocities reported here, and CCD light curves published by Jensen et al., yield component masses of $9.3\pm 0.7$ and $5.6\pm 0.5 \enspace M_\odot$, respectively. The radii are $5.6\pm 0.2$ and $5.3\pm 0.2 \enspace R_\odot$ with the...

Four colour photometry of late-type binary systems - I. First light curves of ZZ Ursae Majoris

This paper presents first complete uvby light curves of the late-type detached eclipsing binary ZZ UMa (, ). This binary system has been observed during eight campaigns at the Calar Alto Observatory (Almeria, Spain)and at the Sierra Nevada Observatory (Granada, Spain). 294 points distributed over the binary period and covering both eclipses are given. The comparison stars used to...