VVV WIN 1733$-$3349: a low extinction window to probe the far side of
  the Milky Way bulge
  Windows of low extinction in the Milky Way (MW) have been used along the past
decades for the study of the Galactic structure and the stellar population
across the inner bulge and disk. Here we report the analysis of another low
extinction near-IR window discovered by the VISTA Variables in the V\'ia
L\'actea Survey. VVV WIN 1733$-$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 $A_{Ks} =
0.61\pm0.08$ 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.
