subroutine CAL_getEncircledEnergy(E, theta, Radius)

- E: energy in eV for which the enclosed energy value will be computed
- theta: field angle in arcsec which defines the position of the PSF barycenter and the center of the circular extraction window.
- Radius: radius specification in mm of the window in which the enclosed energy has to be calculated. It is assumed that the extraction window is circular and perfectly centered on the PSF barycenter.

Michael Smith 2011-09-20