VVV Survey Microlensing: the Galactic Latitude Dependence
  We search for microlensing events in fields along the Galactic minor axis,
ranging from the Galactic center to -3.7<b< 3.9 deg., using the VVV survey
near-IR photometry. The new search is made across VVV tiles b291, b305, b319,
b347, b361 and b375, covering a total area of about 11.5 deg.^2. We find a
total of N=238 new microlensing events in this new area, N=74 of which are
classified as bulge red clump (RC) giant sources. Combining them with N=122
events that we had previously reported in the Galactic center (VVV tile b333),
allows us to study the latitude distribution of the microlensing events
reaching the Galactic plane at b=0^0 for the first time. We find a very strong
dependence of the number of microlensing events with Galactic latitude, number
that increases rapidly towards the Galactic center by one order of magnitude
from |b|=2 deg. to b=0 deg. with a much steeper gradient than with Galactic
longitude. The microlensing event population shows a flattened distribution
(axial ratio b/a \approx 1.5). The final sample shows a shorter mean timescale
distribution than the Galactic plane sample for both, the complete population
and RC stars.
