J/AJ/153/179 VVV Survey RR Lyr stars in Southern Galactic plane (Minniti+, 2017)
Characterization of the VVV Survey RR Lyrae population across the Southern
Galactic plane.
Minniti D., Dekany I., Majaess D., Palma T., Pullen J., Rejkuba M.,
Alonso-Garcia J., Catelan M., Contreras Ramos R., Gonzalez O.A., Hempel M.,
Irwin M., Lucas P.W., Saito R.K., Tissera P., Valenti E., Zoccali M.
<Astron. J., 153, 179-179 (2017)>
=2017AJ....153..179M 2017AJ....153..179M (SIMBAD/NED BibCode)
ADC_Keywords: Surveys ; Milky Way ; Stars, variable ; Photometry, infrared ;
Extinction ; Abundances, [Fe/H] ; Stars, distances
Keywords: Galaxy: structure - stars: variables: RR Lyrae - surveys
Abstract:
Deep near-IR images from the VISTA Variables in the Via Lactea (VVV)
Survey were used to search for RR Lyrae stars in the Southern Galactic
plane. A sizable sample of 404 RR Lyrae of type ab stars was
identified across a thin slice of the fourth Galactic quadrant
(295°<l<350°, -2.24°<b←1.05°). The sample's distance
distribution exhibits a maximum density that occurs at the bulge
tangent point, which implies that this primarily Oosterhoff type I
population of RRab stars does not trace the bar delineated by their
red clump counterparts. The bulge RR Lyrae population does not extend
beyond l∼340°, and the sample's spatial distribution presents
evidence of density enhancements and substructure that warrants
further investigation. Indeed, the sample may be employed to evaluate
Galactic evolution models, and is particularly lucrative since half of
the discovered RR Lyrae are within reach of Gaia astrometric
observations.
Description:
The NIR VISTA Variables in the Via Lactea (VVV) Survey observations
were acquired with the VIRCAM camera at the VISTA 4.1m telescope at
ESO Paranal Observatory. In the disk fields typically 70 epochs of
observations were acquired in the Ks-band between the years 2010 and
2015, in addition to complementary single-epoch observations in the
ZYJH bands. The 16 NIR detectors of VIRCAM produce an image of
11.6'*11.6' and a pixel scale of 0.34''/pixel. The deep multi-epoch
Ks band photometry allows us to unveil faint variable sources deep
in the disk regions of our Galaxy. A search for RRab stars was made
throughout tiles d001 to d038 of the VVV survey's disk field, which is
a thin slice through the Galactic plane spanning 295<l<350°, and
-2.24°<b←1.05°. The total area covered is nearly 57 sq. deg,
and the limiting magnitude in the specified tiles spans 17.5 to
18.5mag in the Ks-band.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 78 404 RR Lyrae sample photometric observations
table2.dat 27 404 Measured stellar parameters
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See also:
III/176 : RR Lyrae Metallicities (Layden 1994)
J/A+A/591/A145 : VVV Survey outer bulge RRab stars (Gran+, 2016)
J/MNRAS/446/2251 : Southern Catalina Survey type-ab RR Lyrae (Torrealba+, 2015)
J/AJ/149/99 : VVV globulars. I. (Alonso-Garcia+, 2015)
J/ApJ/810/L20 : VISTA KS photometry of EWS 2012-BLG-548 (Minniti+, 2015)
J/A+A/566/A120 : 3D dust extinction in Milky Way bulge (Schultheis+, 2014)
J/AJ/146/21 : LINEAR. II. Catalog of RR Lyrae stars (Sesar+, 2013)
J/A+A/550/A42 : Extinction map towards the Galactic bulge (Chen+, 2013)
J/MNRAS/427/3374 : QUEST RR Lyrae Survey III. (Mateu+, 2012)
J/ApJ/724/799 : RR Lyrae variables in M33. II. (Yang+, 2010)
J/A+A/502/505 : Ks photometry of LMC RR Lyrae (Borissova+, 2009)
J/ApJ/678/865 : LONEOS-I RR Lyrae stars (Miceli+, 2008)
J/ApJ/678/851 : RR Lyrae survey in the Galactic Halo (Keller+, 2008)
J/AJ/135/631 : Reddenings for MACHO bulge RR0 Lyrae stars (Kunder+, 2008)
J/MNRAS/384/1583 : JHK light curves of RR Lyr (Sollima+, 2008)
J/AJ/132/714 : QUEST RR Lyrae survey. II. Halo overdensities (Vivas+, 2006)
J/ApJ/542/257 : MACHO LMC first-overtone RR Lyrae (Alcock+, 2000)
J/AJ/108/1016 : Kinematics of local RR lyrae stars. I. (Layden, 1994)
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1- 3 I3 --- Star [2/584] RR Lyrae identifier (VVV-RRL-)
5- 6 I2 h RAh Hour of Right Ascension (J2000)
8- 9 I2 min RAm Minute of Right Ascension (J2000)
11- 15 F5.2 s RAs Second of Right Ascension (J2000)
17 A1 --- DE- Sign of the Declination (J2000)
18- 19 I2 deg DEd Degree of Declination (J2000)
21- 22 I2 arcmin DEm Arcminute of Declination (J2000)
24- 27 F4.1 arcsec DEs Arcsecond of Declination (J2000)
29- 35 F7.3 deg GLON [296.473/350.06] Galactic longitude
37- 42 F6.3 deg GLAT [-2.245/-1.05] Galactic latitude
44- 49 F6.3 mag Ksmag [11.74/16.64] Apparent Ks band magnitude
51- 55 F5.3 mag J-Ks [0.33/2.87]? The (J-Ks) color index
57- 62 F6.3 mag H-Ks [-0.29/0.98]? The (H-Ks) color index
64- 72 F9.7 d Per [0.35/0.96] Period
74- 78 F5.3 mag Amp [0.06/0.55] Amplitude
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Byte-by-byte Description of file: table2.dat
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Bytes Format Units Label Explanations
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1- 3 I3 --- Star [2/584] RR Lyrae identifier (VVV-RRL-)
5- 9 F5.3 mag E(J-Ks) [0/2.72] The (J-Ks) color excess
11- 15 F5.3 mag AKs [0/1.44] The Ks band extinction
17- 22 F6.3 kpc Dist [0/18.43] Distance
24- 27 F4.1 [Sun] [Fe/H] [-2.7/-0.3] Metallicity
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History:
From electronic version of the journal
(End) Prepared by [AAS]; Sylvain Guehenneux [CDS] 07-Aug-2017