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eimsimreduce (eimsim-2.4.2) [xmmsas_20211130_0941-20.0.0]

For $p=$ each of the input source-list columns X, Y and FLUX: makes a frequency histogram of relative $p$ offset.

`Frequency histogram' means that the area under this histogram is equal to the number of rows $N$ in the merged list. The $x$ axis of the plot is the quantity

$\displaystyle \delta_i = \frac{\Delta p_i - \frac{1}{N}\sum_1^N \Delta p_i}{\sigma_{p,i}}
$\displaystyle \Delta p_i = p_\mathrm{det}-p_\mathrm{sim}.
The interpretation of these $p$ quantities in column terms, taking for the sake of an example the $Y$ spatial coordinate, is $p_\mathrm{det}=$ Y, $p_\mathrm{sim}=$ SIM_Y and $\sigma_{p,i}=$ Y_ERR.

These histograms are written to tables named $p$REL.

Figure 1: Fluxes of simulated vs detected sources (100 runs, 2xmm detection).

Figure 2: The variation of matching probability with source brightness (100 runs, 2xmm detection).

XMM-Newton SOC -- 2021-11-30