XMM-Newton Science Analysis System


omphotom (omphotom-1.5.1) [xmmsas_20230412_1735-21.0.0]

Weighting of the equations

The weighting factor for each pixel used in the least-squares fit depends on the parameter weighting, which can have a value of either 1 (the default value with weights of $1/\sigma$, where $sigma$ is the pixel variance ( $\sqrt{pixel value}$), or 2 with a pixel weighting value of 1.