J/ApJ/697/1741 Warped disks of YSOs in Galactic center (Bartko+, 2009)
Evidence for warped disks of young stars in the Galactic Center.
Bartko H., Martins F., Fritz T.K., Genzel R., Levin Y., Perets H.B.,
Paumard T., Nayakshin S., Gerhard O., Alexander T., Dodds-Eden K.,
Eisenhauer F., Gillessen S., Mascetti L., Ott T., Perrin G., Pfuhl O.,
Reid M.J., Rouan D., Sternberg A., Trippe S.
<Astrophys. J., 697, 1741-1763 (2009)>
=2009ApJ...697.1741B 2009ApJ...697.1741B
ADC_Keywords: Stars, early-type ; Radial velocities ; Photometry, infrared ;
Proper motions ; Stars, Wolf-Rayet ; Stars, O
Keywords: Galaxy: center - stars: early-type - stars: formation -
stars: luminosity function, mass function - stellar dynamics
Abstract:
The central parsec around the supermassive black hole in the Galactic
center (GC) hosts more than 100 young and massive stars. Outside the
central cusp (R∼1") the majority of these O and Wolf-Rayet (W-R) stars
reside in a main clockwise system, plus a second, less prominent disk
or streamer system at large angles with respect to the main system.
Here we present the results from new observations of the GC with the
AO-assisted near-infrared imager NACO and the integral field
spectrograph SINFONI on the ESO/VLT. These include the detection of 27
new reliably measured W-R/O stars in the central 12" and improved
measurements of 63 previously detected stars, with proper motion
uncertainties reduced by a factor of 4 compared to our earlier work.
Based on the sample of 90 well measured W-R/O stars, we develop a
detailed statistical analysis of their orbital properties and
orientations. We show that half of the W-R/O stars are compatible with
being members of a clockwise rotating system.
Description:
The data set previously analyzed by Paumard et al. (2006, Cat.
J/ApJ/643/1011) contained 63 reliably (labeled "quality 2") measured
W-R/O stars in the innermost 12" and several candidates. In 2006-2008
we carried out new observations with the integral field spectrograph
SINFONI at the ESO/VLT. We covered two regions west and north of
Sgr A* with the AO scale (25mas/pixel) resulting in a final K-band
full width at half-maximum (FWHM) of typically about 100mas.
In addition, for all these early-type stars we derived proper motions
from the NAOS/CONICA imaging data set of the GC covering six epochs
from May 2002 to March 2007.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 63 90 K magnitudes, positions, proper motions and
radial velocities of the 90 W-R/O stars used in
our analysis
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See also:
J/A+A/499/483 : NIR observations of sources in galactic center (Buchholz+,
2009)
J/ApJ/681/1254 : Radial velocities of stars in the Galactic Center (Zhu+ 2008)
J/ApJ/643/1011 : Early-type stars in the center of the Galaxy (Paumard+ 2006)
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1- 2 I2 --- Seq Running sequence number
4- 8 F5.2 mag Kmag The K band magnitude (1)
10- 14 F5.2 arcsec X Projected X angular distance from SgrA* (2)
16- 20 F5.2 arcsec Y Projected Y angular distance from SgrA* (2)
22- 26 F5.2 arcsec d Projected angular distance from SgrA*
28- 34 F7.2 km/s vRA Proper motion velocity along Right Ascension (3)
36- 40 F5.2 km/s e_vRA The 1σ error in vRA
42- 48 F7.2 km/s vDE Proper motion velocity along Declination (3)
50- 54 F5.2 km/s e_vDE The 1σ error in vDE
56- 59 I4 km/s RV Heliocentric radial velocity
61- 63 I3 km/s e_RV The 1σ error in RV
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Note (1): The uncertainty on the observed magnitude is 0.1mag.
Note (2): Typical position uncertainties are as low as 0.0002".
Note (3): Assuming R0=8kpc.
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History:
From electronic version of the journal
(End) Greg Schwarz [AAS], Emmanuelle Perret [CDS] 31-May-2011