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evigweight (evigweight-1.6) [xmmsas_20050815_1803-6.5.0]

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Event processing

evigweight computes a weight for each photon j falling at detector coordinates $(detx_j,dety_j)$ and of energy (PI) $E_j$ by the inverse of the ratio of the effective area at that position to the central effective area (at the same energy):

\begin{displaymath}
w_j \; = \; \frac{A_{0,0}(E_j)}{A_{detx_j,dety_j}(E_j)}
\end{displaymath} (2)

This weight is stored by default as column WEIGHT (the name can be changed setting weightcolname).



XMM-Newton SOC/SSC -- 2005-08-16