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Interpolation method Point-Spread Function Fitting Extended Sources Home Index

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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.


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