Top: the distributions of the intrinsic variability in pixels of 3.5° × 3.5° area (shown nearby) centered on the IGR J18450-0435. In green is B₁ distribution in the range (min,2m − min) here representing the local intrinsic variance background, in red is the sources contribution, f(x) is the Gaussian distribution. Bottom: the 3.5° × 3.5° area (shown nearby) centered on the GC source 1A 1743-288. In green is B₁ distribution in the range (min,2m − min), in blue is B₂ distribution from the empty region in GC here representing the local intrinsic variance background, in red and f(x) are same as above.