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: http://xmm.vilspa.esa.es/calibration/documentation/CALHB/node30.html
Дата изменения: Tue Sep 20 19:45:18 2011 Дата индексирования: Sun Apr 10 21:19:51 2016 Кодировка: Поисковые слова: molecular cloud |
The encircled energy function is calculated by integrating the PSF, described as a single King function, out to the input radius by:
Where is the core radius in arcseconds and
is the slope.
The parameters of the King function have been measured for the three mirror modules and described in terms of photon energy and off-axis angle by the formulae:
From these formulae the parameters and
have been tabulated as a function of
energy and
and stored in the CCF components XRT?_XPSF. This routine uses spline
fitting to interpolate between these tabulated values.