Astrometric radial velocities for nearby stars

The Age of Old Galactic Populations

Highlights of Astronomy ◽

10.1017/s1539299600022152 ◽

1998 ◽

Vol 11 (1) ◽

pp. 560-561

Author(s):

M. Grenon

Keyword(s):

High Velocity ◽

Radial Velocities ◽

Thick Disk ◽

Early Evolution ◽

Galactic Bulge ◽

Colour Class ◽

The Galaxy ◽

Nearby Stars

As a preparation to the HIPPARCOS mission, a large observing programme on NLTT stars (propermotion > 0.18 ″/yr) was started in Genevaphotometry. The original programme consists of 10047 stars brighter than mR = 11.5, or mR = 12.5 if of colour class m. Among them, 7813 targets could be included in the HIPPARCOS programme, selected according to their observability and internal priorities in favour of large parallaxe stars (photometric distances < 100 pc) and high-velocity stars. The bulk of new nearby, halo, mild-metal poor and SMR stars in the HIP Catalogue originates from this proposal (N° 139). No less than 208 new nearby stars with π ≥ 40 mas were discovered south of δ +10°, the closest has π(HIP)= 182 mas. Radial velocities were obtained with CORAVEL at OHP and ESO. Most aspects of the early evolution of the Galaxy may be addressed with this sample. Here we discuss, as examples, the ages of the thick disk and of the galactic bulge.

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Esiderata for nearby - star quantities observable with small telescope

Symposium - International Astronomical Union ◽

10.1017/s0074180900151393 ◽

1986 ◽

Vol 118 ◽

pp. 247-249

Author(s):

W. Gliese

Keyword(s):

Broad Band ◽

Radial Velocities ◽

General Assembly ◽

New Delhi ◽

Proper Motions ◽

Nearby Star ◽

Small Telescope ◽

General Catalogue ◽

Nearby Stars

At the General Assembly of the IAU at New Delhi van Altena reported on the new General Catalogue of Trigonometric Stellar Parallaxes (GCTSP) which was completed recently at the Yale Observatory. Time seems to be ripe now for the compilation of a Third Catalogue of Nearby Stars which will include all objects known to be nearer than 25 parsecs. This catalogue will contain positions, proper motions, radial velocities, spectral types, broad-band photometry, and parallaxes - quantities won by observations.

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The RAVE harvest: from the relation between abundances and kinematic of the Milky Way stars to tools for the abundance analysis of the spectra

Proceedings of the International Astronomical Union ◽

10.1017/s1743921313006480 ◽

2013 ◽

Vol 9 (S298) ◽

pp. 292-297

Author(s):

Corrado Boeche ◽

Keyword(s):

Milky Way ◽

Radial Velocities ◽

Proper Motions ◽

Chemical Abundances ◽

Stellar Spectra ◽

Chemical Gradients ◽

Single Process ◽

The Galaxy ◽

Nearby Stars ◽

Kinematic Information

AbstractRAVE is a spectroscopic survey of the Milky Way which collected more than 500,000 stellar spectra of nearby stars in the Galaxy. The RAVE consortium analysed these spectra to obtain radial velocities, stellar parameters and chemical abundances. These data, together with spatial and kinematic information like positions, proper motions, and distance estimations, make the RAVE database a rich source for galactic archaeology. I present recent investigations on the chemo-kinematic relations and chemical gradients in the Milky Way disk using RAVE data and compare our results with the Besançon models. I also present the code SPACE, an evolution of the RAVE chemical pipeline, which integrates the measurements of stellar parameters and chemical abundances in one single process.

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Radial Velocity Measurements with Objective Prisms for the Hipparcos Program

International Astronomical Union Colloquium ◽

10.1017/s0252921100098766 ◽

1984 ◽

Vol 88 ◽

pp. 196-198

Author(s):

Ch. Fehrenbach

Keyword(s):

Radial Velocity ◽

European Space Agency ◽

Stellar Dynamics ◽

High Accuracy ◽

Radial Velocities ◽

High Dispersion ◽

Proper Motions ◽

Space Agency ◽

Nearby Stars ◽

Absolute Magnitudes

In 1986, the European Space Agency (ESA) will launch an astrometrie satellite, Hipparcos (see ESA SP-177) with the objective of measuring positions for 200,000 stars. Proper motions will be determined with an accuracy of 0.002 "/yr. It is also very important to have radial velocities for the program stars.We will show here that an accuracy of 4 to 5 km/s for the radial velocity is good enough for a number of studies. For stellar studies, we need highly accurate radial velocities, and correlation methods (Griffin, Mayor et al.) allow that but are restricted to cool stars. Radial velocities are also needed for studies of stellar dynamics. In the case of star clusters (open and globular) we need a high accuracy, however the study of motions of stars in our galaxy do not require such a high accuracy. Only by increasing the sample can we improve our knowledge. In Table I we give data for the velocity ellipsoid. Kinematical data are from Allen and we have added absolute magnitudes and distances for stars having mv = 7.5. From an examination of this table we see that an accuracy of 4-5 km/s is good enough to study B star motions. The last column gives the dispersion in proper motion, and some of the values are astonishing, but it is well known that the proper motions for the nearby stars show a very high dispersion.

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COMMISSION 30: RADIAL VELOCITIES

Proceedings of the International Astronomical Union ◽

10.1017/s1743921308025763 ◽

2008 ◽

Vol 4 (T27A) ◽

pp. 316-325

Author(s):

Stephane Udry ◽

Guillermo Torres ◽

Birgitta Nordström ◽

Francis C. Fekel ◽

Kenneth C. Freeman ◽

...

Keyword(s):

Recent Work ◽

Extrasolar Planets ◽

Radial Velocities ◽

Wide Range ◽

Nearby Stars

This three-year period has seen considerable activity in the Commission, with a wide range of applications of radial velocities as well as a significant push toward higher precision. The latter has been driven in large part by the exciting research on extrasolar planets. This field is now on the verge of detecting Earth-mass bodies around nearby stars, as demonstrated by recent work summarized below, and radial velocities continue to play a central role.

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On the Inhomogeneity of Chemical Composition over the Surface of 21 Per

International Astronomical Union Colloquium ◽

10.1017/s0252921100080659 ◽

1976 ◽

Vol 32 ◽

pp. 343-349

Author(s):

Yu.V. Glagolevsky ◽

K.I. Kozlova ◽

V.S. Lebedev ◽

N.S. Polosukhina

Keyword(s):

Chemical Composition ◽

Spectral Line ◽

Variable Star ◽

Radial Velocities ◽

Crimean Astrophysical Observatory ◽

Line Intensities ◽

Magnetic Variable

SummaryThe magnetic variable star 21 Per has been studied from 4 and 8 Å/mm spectra obtained with the 2.6 - meter reflector of the Crimean Astrophysical Observatory. Spectral line intensities (Wλ) and radial velocities (Vr) have been measured.

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