XMM-Newton SAS Home Page
XMM-Newton Science Analysis System


omdetect (omdetect-5.34.1) [xmmsas_20160201_1833-15.0.0]

Point-Spread Function Fitting Point-Spread Function Fitting Extended Sources (non-mosaiced images) Home Index

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 ( $\sqrt{pixel value}$).


XMM-Newton SOC/SSC -- 2016-02-01