J/A+A/423/517 Velocities of Galactic disk late-type stars (Rocha-Pinto+, 2004)
Chemical enrichment and star formation in the Milky Way disk.
III. Chemodynamical constraints.
Rocha-Pinto H.J., Flynn C., Hanninen J., Scalo J., Maciel W.J., Hensler G.
<Astron. Astrophys. 423, 517 (2004)>
=2004A&A...423..517R 2004A&A...423..517R
ADC_Keywords: Stars, late-type ; Space velocities ; Radial velocities
Keywords: stars: late-type - stars: statistics - Galaxy: evolution -
Galaxy: solar neighbourhood
Abstract:
In this paper, we investigate some chemokinematical properties of the
Milky Way disk, by using a sample composed by 424 late-type dwarfs. We
show that the velocity dispersion of a stellar group increases
steadily the age of the stellar group, according to a disk heating law
proportional to t0.26, where t is the age of the stellar group.
The temporal evolution of the vertex deviation is considered in
detail. It is shown that the vertex deviation does not follow a smooth
variation with time. Previous studies in the literature seem to not
have found it due to the use of statistical ages for stellar groups,
rather than individual ages. The possibility to use the orbital
parameters of a star to derive information about its birthplace is
investigated, and we show that the mean galactocentric radius is
likely to be the most reliable stellar birthplace indicator. However,
this information cannot be used presently to derive radial
evolutionary constraints, due to an intrinsic bias present in all
samples constructed from nearby stars.
Description:
Chemokinematical parameters for 424 solar neighbourhood late-type
dwarfs. For each star, we give the HD number (or BD number), the
chromospheric index log R'HK, the chromospheric age and photometric
metallicity, the peculiar velocities U, V and W w.r.t. the LSR and
their their respective errors e_U, e_V and e_W, the orbital parameters Rm
(average galactocentric radius), Rp (perigalactic radius), Zmax
(maximum height above the plane) and e (eccentricity).
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 80 424 Chemokinematical parameters for 424 stars
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See also:
J/AJ/118/895 : Milky way and stellar distributions (Tiede+ 1999)
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1- 10 A10 --- Name HD or BD designation
12- 16 F5.2 --- logR'HK Chromospheric activity index (G1)
18- 22 F5.2 [Sun] [Fe/H] Stellar photometric metallicity
24- 29 F6.1 km/s RV Radial velocity
31- 35 F5.2 Gyr Age Stellar chromospheric age
37- 40 I4 km/s Uvel U velocity component w.r.t the LSR
42- 45 I4 km/s Vvel V velocity component w.r.t the LSR
47- 50 I4 km/s Wvel W velocity component w.r.t the LSR
52- 53 I2 km/s e_Uvel Error in U velocity
55- 56 I2 km/s e_Vvel Error in V velocity
58- 59 I2 km/s e_Wvel Error in W velocity
61- 65 F5.2 kpc Rm ? Average orbital galactocentric radius
67- 70 F4.2 kpc Rp ? Perigalacticon galactocentric radius
72- 75 F4.2 kpc Zmax ? Maximum heigh above the Galactic plane
77- 80 F4.2 --- ecc ? Orbital eccentricity
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Global Notes:
Note (G1): the chromospehric index is defined as the flux ratio of CaII
in emission to the bolometric flux of the photosphere
Acknowledgements: Walter Maciel
References:
Rocha-Pinto et al., Paper I 2000A&A...358..850R 2000A&A...358..850R
Rocha-Pinto et al., Paper II 2000A&A...358..869R 2000A&A...358..869R
(End) Patricia Vannier [CDS] 28-Jun-2004