Three dimensional interstellar extinction map towards the Galactic Bulge
  Studies of the properties of the inner Galactic Bulge depend strongly on the
assumptions about the interstellar extinction. Most of the extinction maps
available in the literature lack the information about the distance.
  We combine the observations with the Besancon model of the Galaxy to
investigate the variations of extinction along different lines of sight towards
the inner Galactic bulge as a function of distance. In addition we study the
variations in the extinction law in the Bulge. We construct color-magnitude
diagrams with the following sets of colors: H-Ks and J-Ks from the VVV
catalogue as well as Ks-[3.6], Ks-[4.5], Ks-[5.8] and Ks-[8.0] from GLIMPSE-II
catalogue matched with 2MASS. Using the newly derived temperature-color
relation for M giants that match better the observed color-magnitude diagrams
we then use the distance-color relations to derive the extinction as a function
of distance. The observed colors are shifted to match the intrinsic colors in
the Besan\c{c}on model, as a function of distance, iteratively thereby creating
an extinction map with three dimensions: two spatial and one distance dimension
along each line of sight towards the bulge. Colour excess maps are presented at
a resolution of 15' x 15' for 6 different combinations of colors, in distance
bins of 1 kpc. The high resolution and depth of the photometry allows to derive
extinction maps to 10 kpc distance and up to 35 magnitudes of extinction in Av
(3.5 mag in Aks). Integrated maps show the same dust features and consistent
values with the other 2D maps. Starting from the color excess between the
observations and the model we investigate the extinction law in near-infrared
and its variation along different lines of sight.
