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Дата изменения: Thu Jun 29 00:15:35 2006
Дата индексирования: Sat Dec 22 11:44:19 2007
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XMM-Newton Science Analysis System


evigweight (evigweight-1.6) [xmmsas_20060628_1801-7.0.0]

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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):

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

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