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

Saito, R K; Minniti D.; Benjamin R.A.; Navarro, M. G.; Alonso-Garciá J.; Gonzalez, O. A.; Kammers R.; Surot F.

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 disc. Here, we report the analysis of another low extinction near-IR window discovered by the VISTA Variables in the Via Lactea Survey (VVV). 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 +/- 0.08 mag, which ismuch 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.

Más información

Título según WOS: VVV WIN 1733-3349: a low extinction window to probe the far side of the Milky Way bulge
Título según SCOPUS: VVV WIN 1733-3349: A low extinction window to probe the far side of the Milky Way bulge
Título de la Revista: MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
Volumen: 494
Número: 1
Editorial: OXFORD UNIV PRESS
Fecha de publicación: 2020
Página de inicio: L32
Página final: L36
Idioma: English
DOI:

10.1093/MNRASL/SLAA028

Notas: ISI, SCOPUS