J/AJ/127/1567 Asymmetric thick disk. II. Kinematics (Parker+, 2004)
The asymmetric thick disk: a star-count and kinematic analysis.
II. The kinematics.
Parker J.E., Humphreys R.M., Beers T.C.
<Astron. J., 127, 1567-1578 (2004)>
=2004AJ....127.1567P 2004AJ....127.1567P
ADC_Keywords: Stars, halo ; Radial velocities ; Abundances, [Fe/H]
Keywords: Galaxy: halo - Galaxy: kinematics and dynamics -
Galaxy: stellar content - Galaxy: structure
Abstract:
We report a kinematic signature associated with the observed asymmetry
in the distribution of thick-disk/inner halo stars interior to the
solar circle described in Paper I (Parker et al.,
2003AJ....126.1346P 2003AJ....126.1346P). In that paper, we found a statistically
significant excess (20%-25%) of stars in quadrant I
(l∼20°-55°) both above and below the plane (b~±25° to
b~±45°) compared with the complementary region in quadrant IV.
We have measured Doppler velocities for 741 stars, selected according
to the same magnitude and color criteria, in the direction of the
asymmetry and in the corresponding fields in quadrant IV. We have also
determined spectral types and metallicities measured from the same
spectra.
Description:
We used Hydra, a multiobject spectrometer on the 4m Blanco Telescope
at Cerro Tololo Inter-American Observatory (CTIO) on 1999 Apr 15-18
and 2000 May 27-30 and on the WIYN2 3.5m telescope at Kitt Peak
National Observatory (KPNO) on 2000 Jun 2-5.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table4.dat 73 742 Velocities, spectral types and metallicities
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Byte-by-byte Description of file: table4.dat
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Bytes Format Units Label Explanations
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1- 5 A5 --- Field Field identification (G1)
7- 13 I7 --- APS APS star number (G1) (1)
15- 18 A4 --- ORun Observation run number (2)
20- 24 F5.2 mag Omag POSS I O-band magnitude
26- 29 F4.1 mag O-E POSS I (O-E) color index
31- 35 F5.1 deg GLON Galactic longitude
37- 40 F4.1 deg GLAT Galactic latitude
42- 47 F6.1 km/s HRV Heliocentric radial velocity
49- 52 F4.1 km/s e_HRV The 1 σ error in HRV
54- 55 I2 --- NLine Number of lines
57- 61 F5.2 [-] [Fe/H] ? Metallicity
62 A1 --- f_[Fe/H] [-N:X] Flag on [Fe/H] (3)
64- 67 F4.2 [-] e_[Fe/H] ? The 1σ error in [Fe/H]
69- 73 A5 --- SpType MK spectral type
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Note (1): Positions for the stars can be obtained from the Minnesota Automated
Plate Scanner (MAPS) Catalog of the POSS I using either the SQL-based
query for individual stars (http://aps.umn.edu/catalog/sql.html) or
the sky-box query (http://aps.umn.edu/catalog) for a region on the sky.
Note (2): Observation run numbers as follows:
1 = CTIO 1999
2 = CTIO 2000
3 = WIYN 2000
Note (3): Note on [Fe/H] as follows:
X = Star with spectra considered too noisy to obtain a reasonable
abundance estimate. Not used in the measurement of the mean.
: = Star with inferred (B-V)0 color outside the "optimum range."
N = Star with a noisy spectrum, but with an abundance estimate.
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Global notes:
Note (G1): Nomenclature notes:
Objects are identified as MAPS Field-APS (MAPS AFFF-NNNNNNN)
in Simbad .
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History:
From electronic version of the journal
References:
Parker et al., Paper I 2003AJ....126.1346P 2003AJ....126.1346P
(End) Greg Schwarz [AAS], Patricia Vannier [CDS] 07-May-2004