Bulge RR Lyrae stars in the VVV tile $\text{b201}$

Abstract

The VISTA Variables in the Vía Láctea (VVV) Survey is one of the six ESO public surveys currently ongoing at the VISTA telescope on Cerro Paranal, Chile. VVV uses near-IR ($ZYJH{K}_{\mathrm{s}}$) filters that at present provide photometry to a depth of $K_{\mathrm{s}}\sim 17.0$ mag in up to 36 epochs spanning over four years, and aim at discovering more than 10${}^6$ variable sources as well as trace the structure of the Galactic bulge and part of the southern disk. A variability search was performed to find RR Lyrae variable stars. The low stellar density of the VVV tile $\text{b201}$, which is centered at ($\ell ,b$) $\sim$ ($-9^{\circ },-9^{\circ }$), makes it suitable to search for variable stars. Previous studies have identified some RR Lyrae stars using optical bands that served to test our search procedure. The main goal is to measure the reddening, interstellar extinction, and distances of the RR Lyrae stars and to study their distribution on the Milky Way bulge. A total of 1.5 sq deg were analyzed, and we found 39 RR Lyrae stars, 27 of which belong to the ab-type and 12 to the c-type. Our analysis recovers all the previously identified RR Lyrae variables in the field and discovers 29 new RR Lyrae stars. The reddening and extinction toward all the RRab stars in this tile were derived, and distance estimations were obtained through the period--luminosity relation. Despite the limited amount of RR Lyrae stars studied, our results are consistent with a spheroidal or central distribution around $\sim 8.1$ and $\sim 8.5$ kpc. for either the Cardelli or Nishiyama extinction law.

arXiv comment10 pages, 8 figures, accepted for publication in Astronomy and Astrophysics

References in corpus (26)

• The Wide-field Infrared Survey Explorer (WISE): Mission Description and Initial On-orbit Performance
• VISTA Variables in the Via Lactea (VVV): The public ESO near-IR variability survey of the Milky Way
• VVV DR1: The First Data Release of the Milky Way Bulge and Southern Plane from the Near-Infrared ESO Public Survey VISTA Variables in the Via Lactea
• Interstellar Extinction Law toward the Galactic Center III: J, H, Ks bands in the 2MASS and the MKO systems, and 3.6, 4.5, 5.8, 8.0 micron in the Spitzer/IRAC system
• Near-Infrared Photometric Variability of Stars Toward the Orion A Molecular Cloud
• Two Red Clumps and the X-Shaped Milky Way Bulge
• The RR Lyrae Period-Luminosity Relation. I. Theoretical Calibration
• Reddening and metallicity maps of the Milky Way bulge from VVV and 2MASS II. The complete high resolution extinction map and implications for Bulge studies
• VVV Survey Near-Infrared Photometry of Known Bulge RR Lyrae stars: the Distance to the Galactic Center and Absence of a Barred Distribution of the Metal-Poor Population
• The Luminosities and Distance Scales of Type II Cepheid and RR Lyrae variables
• Reddening and metallicity maps of the Milky Way Bulge from VVV and 2MASS. I.The method and minor axis maps
• The distance to the Galactic Centre based on Population-II Cepheids and RR Lyrae stars
• The RR Lyrae Period - K Luminosity relation for Globular Clusters: an observational approach
• The Araucaria Project. The Distance to the Sculptor dwarf spheroidal galaxy from infrared photometry of RR Lyrae stars
• The Optical Gravitational Lensing Experiment: Analysis of the bulge RR Lyrae population from the OGLE-III data
• A pulsational distance to Omega Centauri based on Near-Infrared Period-Luminosity relations of RR Lyrae stars
• Milky Way demographics with the VVV survey. I. The 84-million star colour-magnitude diagram of the Galactic bulge
• The distance to the LMC cluster Reticulum from the K-band Period-Luminosity-Metallicity relation of RR Lyrae stars
• Tracing the Orphan Stream to 55 kpc with RR Lyrae Stars
• Variable stars in the VVV globular clusters. I. 2MASS-GC02 and Terzan10
• Distance to Galactic globulars using the near-infrared magnitudes of RR Lyrae stars: IV. The case of M5 (NGC5904)
• Near-Infrared Observations of RR Lyrae variables in Galactic Globular Clusters: I. The case of M92
• The Extinction Toward the Galactic Bulge from RR Lyrae Stars
• The VVV Templates Project. Towards an Automated Classification of VVV Light-Curves. I. Building a database of stellar variability in the near-infrared
• Computation of the Fourier parameters of RR Lyrae stars by template fitting
• An Oosterhoff Analysis of the Galactic Bulge Field RR Lyrae stars: Implications On Their Absolute Magnitudes

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