VVV WIN 1733$-$3349: a low extinction window to probe the far side of the Milky Way bulge

Abstract

Windows of low extinction in the Milky Way (MW) have been used along the past decades for the study of the Galactic structure and the stellar population across the inner bulge and disk. Here we report the analysis of another low extinction near-IR window discovered by the VISTA Variables in the Vía Láctea Survey. VVV WIN 1733$-$3349 is about half a degree in size and is conveniently located right in the MW plane, at Galactic coordinates $(l,b)=(-5.2,-0.3)$. The mean extinction of VVV WIN 1733$-$3349 is $A_{Ks}=0.61\pm 0.08$ mag, which is much smaller than the extinction in the surrounding area. The excess in the star counts is consistent with the reduced extinction, and complemented by studying the distribution of red clump (RC) stars. Thanks to the strategic low-latitude location of VVV WIN 1733$-$3349, we are able to interpret their RC density fluctuations with the expected overdensities due to the presence of the spiral arms beyond the bulge. In addition, we find a clear excess in the number of microlensing events within the window, which corroborates our interpretation that VVV WIN 1733$-$3349 is revealing the far side of the MW bulge.

arXiv comment5 pages, 4 figures. Accepted for publication in MNRAS Letters

References in corpus (38)

• Maps of Dust IR Emission for Use in Estimation of Reddening and CMBR Foregrounds
• Gaia Data Release 2. Summary of the contents and survey properties
• The Wide-field Infrared Survey Explorer (WISE): Mission Description and Initial On-orbit Performance
• Estimating distances from parallaxes IV: Distances to 1.33 billion stars in Gaia Data Release 2
• GLIMPSE: I. A SIRTF Legacy Project to Map the Inner Galaxy
• VISTA Variables in the Via Lactea (VVV): The public ESO near-IR variability survey of the Milky Way
• The Pan-STARRS1 Surveys
• 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
• Outer structure of the Galactic warp and flare: explaining the Canis Major over-density
• Chemodynamical history of the Galactic Bulge
• Stellar Proper Motions in the Galactic Bulge from deep HST ACS/WFC Photometry
• Low-extinction windows in the inner Galactic Bulge
• The DECam Plane Survey: Optical photometry of two billion objects in the southern Galactic plane
• The First Detection of Blue Straggler Stars in the Milky Way Bulge
• Reddening and metallicity maps of the Milky Way Bulge from VVV and 2MASS. I.The method and minor axis maps
• The frequency of snowline-region planets from four-years of OGLE-MOA-Wise second-generation microlensing
• Extinction Map of Baade's Window
• Extinction ratios in the inner Galaxy as revealed by the VVV survey
• Red Giant Branch Bump Brightness and Number Counts in 72 Galactic Globular Clusters Observed with the Hubble Space Telescope
• Empirical photometric calibration of the Gaia Red Clump: colours, effective temperature and absolute magnitude
• Milky Way demographics with the VVV survey. IV. PSF photometry from almost one billion stars in the Galactic bulge and adjacent southern disk
• The Metallicity and Reddening of Stars in the Inner Galactic Bulge
• Star formation history of the Galactic bulge from deep HST imaging of low reddening windows
• OGLE-III Detection of the Anomalous Galactic Bulge Red Giant Branch Bump: Evidence of Enhanced Helium Enrichment
• Milky Way Demographics with the VVV Survey II. Color Transformations and Near-Infrared Photometry for 136 Million Stars in the Southern Galactic Disk
• Hiding its age: the case for a younger bulge
• The structure behind the Galactic bar traced by red clump stars in the VVV survey
• Extinction Maps towards the Milky Way Bulge: 2D and 3D Tests with APOGEE
• A new near-IR window of low extinction in the Galactic plane
• VVV Survey Microlensing Events in the Galactic Center Region
• VVV Survey Microlensing: the Galactic Longitude Dependence
• A Planetary Microlensing Event with an Unusually Red Source Star: MOA-2011-BLG-291
• UKIRT-2017-BLG-001Lb: A giant planet detected through the dust
• Milky Way demographics with the VVV Survey III. Evidence for a Great Dark Lane in the 157 Million Star Bulge Color-Magnitude Diagram
• A Color-Excess Extinction map of the Southern Galactic disk from the VVV and GLIMPSE Surveys
• Mapping the stellar age of the Milky Way bulge with the VVV. II. Deep JKs catalogs release based on PSF photometry
• A low-absorption disk zone at low Galactic latitude in Centaurus

Cited by in corpus (10)

• Mapping the stellar age of the Milky Way bulge with the VVV. III. High resolution reddening map
• VVVX-Gaia Discovery of a Low Luminosity Globular Cluster in the Milky Way Disk
• Confirmation and physical characterization of the new bulge globular cluster Patchick 99 from the VVV and Gaia surveys
• Using classical Cepheids to study the far side of the Milky Way disk. II. The spiral structure in the first and fourth Galactic quadrants
• The VVV Near-IR Galaxy Catalogue beyond the Galactic disk
• The VVV survey: Long-period variable stars I. Photometric catalog of ten VVV/OGLE tiles
• Mapping the stellar age of the Milky Way bulge with the VVV. II. Deep JKs catalogs release based on PSF photometry
• Evidence of distant spiral arms in the Galactic disk quadrant IV from VVV red clump giants
• Confirmation Of Two New Galactic Bulge Globular Clusters: FSR 19 and FSR 25
• Distance and extinction to the Milky Way spiral arms along the Galactic centre line of sight