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rgssources (rgssources-6.3) [xmmsas_20211130_0941-20.0.0]


It is intended to flag in the RGS pipeline sources which are confused with the prime source, so as to allow the end user to assess whether these have a deleterious effect on the spectra of the prime source. For this purpose rgssources calculates, for each source, a value which is stored in a column called CONFUSION. This value is calculated from the following formula:

$\displaystyle C = I^{-1}_{\rm prime}\Big\{p_1 + p_2 \: I \: \exp\Big[-\frac{(\v...
...a)^2}{2b^2} - \frac{(\vert\chi - \chi_{\rm prime}\vert+c)^2}{2d^2}\Big]\Big\}.

Here $C$ is the confusion value, $I$ is the source brightness (ie value of the RATE column) and $\alpha$ and $\chi$ are respectively the dispersion and cross-dispersion angles in arcseconds. The constants $p_1$, $p_2$, $a$, $b$, $c$ and $d$ will eventually be stored in CCF MiscData, but at present are `hard-wired' into the task code, with values as follows:

$\displaystyle \begin{array}[h]{cl}
p_1 & = -0.00653 \;\rm {cts/sec}\\
p_2 & = ...
c & = 2.29 \;\rm {arcsec}\\
d & = 23.3 \;\rm {arcsec}
\end{array} $

XMM-Newton SOC -- 2021-11-30