J/AJ/141/131 Mapping the asymmetric thick disk. III. (Humphreys+, 2011)
Mapping the asymmetric thick disk.
III. The kinematics and interaction with the Galactic bar.
Humphreys R.M., Beers T.C., Cabanela J.E., Grammer S., Davidson K.,
Lee Y.S., Larsen J.A.
<Astron. J., 141, 131 (2011)>
=2011AJ....141..131H 2011AJ....141..131H
ADC_Keywords: Stars, halo; Radial velocities; Abundances, [Fe/H]
Keywords: Galaxy: kinematics and dynamics - Galaxy: structure
Abstract:
In the first two papers of this series, Larsen et al.
(1996ApJ...468L..99L 1996ApJ...468L..99L) describe our faint CCD survey in the inner
Galaxy and map the overdensity of thick disk stars in Quadrant 1 (Q1)
to 5kpc or more along the line of sight. The regions showing the
strongest excess are above the density contours of the bar in the
Galactic disk. In this third paper on the asymmetric thick disk, we
report on radial velocities and derived metallicity parameters for
over 4000 stars in Q1, above and below the plane, and in Quadrant 4
(Q4) above the plane.
Description:
One of the goals of the spectroscopy program is to obtain more
complete spatial coverage and extend the survey to greater distances
than were available to Parker et al. (2004, Cat. J/AJ/127/1567). In
addition to their original 12 fields, we added 13 fields in Q1 above
and below the plane and 6 fields in Q4 above the plane.
The spectra were obtained with the Hectospec Multi-Object Spectrograph
(MOS) on the MMT 6.5m telescope on Mt. Hopkins for the northern fields
in 2007 and 2008 and with the Hydra MOS on the Blanco 4m at CTIO in
2006 and 2008 for the fields with declinations below -20°.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
tablea1.dat 118 2306 Catalog of velocities, metallicity, and
atmospheric parameters (CCD Photometry)
tablea2.dat 118 1899 Catalog of velocities, metallicity, and
atmospheric parameters (MAPS photometry)
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See also:
J/AJ/127/1567 : Asymmetric thick disk. II. Kinematics (Parker+, 2004)
Byte-by-byte Description of file: tablea1.dat
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Bytes Format Units Label Explanations
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1- 15 A15 --- ID Object Identification String (HLLL+BB-NNNNNN)
17- 22 F6.2 deg GLON Galactic longitude
24- 29 F6.2 deg GLAT Galactic latitude
31- 35 F5.2 mag Vmag V band magnitude
37- 41 F5.2 mag B-V The (B-V) color index
43- 48 F6.1 km/s RV ?=-999 Heliocentric velocity estimate (G1)
50- 53 F4.1 km/s e_RV ?=0 Uncertainty in RV
55- 60 F6.1 km/s Vlsr ?=-999 Velocity in LSR frame (G1)
62- 67 F6.1 km/s/kpc omega ?=0 Angular Velocity ω (G1)
69- 74 F6.2 [Sun] [Fe/H] ?=-99 Metallicity (G1)
76- 79 F4.2 [Sun] e_[Fe/H] ?=0 Uncertainty in [Fe/H]
81- 86 F6.2 [Sun] [a/Fe] ?=-99 The [α/Fe] estimate (G1)
88- 91 F4.2 [Sun] e_[a/Fe] ?=0 Uncertainty in [a/Fe]
93- 96 I4 K Teff ?=-99 Effective temperature estimate (G1)
98-100 I3 K e_Teff ?=0 Uncertainty in Teff
102-107 F6.2 [cm/s2] log(g) ?=-99 Log surface gravity estimate (G1)
109-112 F4.2 [cm/s2] e_log(g) ?=0 Uncertainty in log(g)
114-118 F5.1 kpc Dist Distance estimate
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Byte-by-byte Description of file: tablea2.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 15 A15 --- ID Object Identification String (PNNN-NNNNNNN)
17- 22 F6.2 deg GLON Galactic longitude
24- 29 F6.2 deg GLAT Galactic latitude
31- 35 F5.2 mag Omag O magnitude
37- 41 F5.2 mag O-E The (O-E) color index
43- 48 F6.1 km/s RV ?=-999 Heliocentric Velocity estimate (G1)
50- 53 F4.1 km/s e_RV ?=0 Uncertainty in RV
55- 60 F6.1 km/s Vlsr ?=-999 Velocity in LSR frame (G1)
62- 67 F6.1 km/s/kpc omega ?=0 Angular Velocity ω (G1)
69- 74 F6.2 [Sun] [Fe/H] ?=-99 Metallicity (G1)
76- 79 F4.2 [Sun] e_[Fe/H] ?=0 Uncertainty in [Fe/H]
81- 86 F6.2 [Sun] [a/Fe] ?=-99 The [α/Fe] estimate (G1)
88- 91 F4.2 [Sun] e_[a/Fe] ?=0 Uncertainty in [a/Fe]
93- 96 I4 K Teff ?=-99 Effective temperature estimate (G1)
98-100 I3 K e_Teff ?=0 Uncertainty in Teff
102-107 F6.2 [cm/s2] log(g) ?=-99 Log surface gravity estimate (G1)
109-112 F4.2 [cm/s2] e_log(g) ?=0 Uncertainty in log(g)
114-118 F5.1 kpc Dist Distance estimate
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Global Notes:
Note (G1): -999 and -99 indicate unknown values.
The values used for the computations are (from section 3):
* The LSR solar motion is (u,v,w)=(9,12,7)km/s
* The distance to the galactic center is R=8kpc
* The galactocentric rotational velocity of the Sun is V=220km/s
* the angular velocity of the Sun is therefore ω=27.5km/s/kpc
History:
From electronic version of the journal
References:
Larsen et al., 1996ApJ...468L..99L 1996ApJ...468L..99L
Parker et al., Paper I 2003AJ....126.1346P 2003AJ....126.1346P
Parker et al., Paper II 2004AJ....127.1567P 2004AJ....127.1567P, Cat. J/AJ/127/1567
(End) Greg Schwarz [AAS], Patricia Vannier [CDS] 03-Aug-2012