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	       SRCALC-IDPOWER  (OASYS-XOPPY version)
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	The IDPower code calculates the power and power densities
	emitted by an insertion device (ID) and the power absorbed
	by a series of optical elements in a beamline.

	IDPower was originally part of the SRCalc suite of routines
	written by Ruben Reininger for calculations used in synchrotron
	radiation beamline design.

	SRCalc run within IGOR using its graphic and programing capabilities.

	The first part of the IDPower program allow to enter the machine
	and ID parameters as well as the description of the beamline components.

	The calculation of the power emitted by the insertion device is based
	on the FORTRAN program, URGENT, written by R.P. Walker and B. Diviacco
	(Rev. Sci. Instrum. 63, 392 (1992).) URGENT can perform several calculations
	related to the radiation emitted by an ID. In particular, the power density
	on a rectangular grid at a given distance from the ID due to either one
	harmonic or due to all the harmonics up to a given value.

	The FORTRAN part of IDPower (its second component) is an expanded version
	of URGENT that calculates the power absorbed by up to 6 optical elements (OE)
	exposed to the ID radiation either from one harmonic or from the first harmonic
	up to a harmonic that shows saturation on the power emitted by the device.
	The expanded FORTRAN code sets up new rectangular grids (representing the
	optical elements) in which the power reflected (or transmitted) by each one
	of the OEs is stored. The code then calculates the power density emitted at
	each photon energy and each grid point. It multiplies this value by the
	reflectivity (or transmission) of each optical element and sums up the values
	for each optical component in its corresponding grid. In the case of planar
	undulators, the mirror reflectivity is either s or p depending on the mirror
	orientation. For helical/elliptical undulators the mirror reflectivity is
	taken as the average between the s and p.

	In the third component of IDPower,  the full beamline is ray traced using
	the same divergence grid as the one used in the Urgent code.

	The fourth component reads the results of the FORTRAN code, maps the values
	of the power densities at the rectangular grids to the illumination
	determined by the ray tracing at the corresponding OE, and generates image
	plots for each OE.  In addition, the parameters of the calculations as well
	as the total power absorbed and maximum absorbed power density at each OE
	are added to the notebook named "Summary".

	IDPower can also calculate the power density at the exit plane of one of
	the optical elements. This is done by an extension that runs a loop using
	random values for the electron beam size and the position along the depth
	of the insertion device.




