XMM-Newton Science Analysis System


omdetect (omdetect-5.34) [xmmsas_20141104_1833-14.0.0]

Meta Index / Home Page / Photometry / Point-Spread Function Fitting

Weighting of the equations

The weighting factor for each pixel used in the least-squares fit is given by $1/\sigma$, where $\sigma$ is the pixel variance ( $\sqrt{pixel value}$).