
==============================  power   =====================================

 Power calculates the transmission in terms of flux or spectral power energy
 as a function of photon energy for a set of up to five attenuators and mirrors.

 It uses the XRAYLIB library to calculate reflectivities and transmissions.


 Input parameters for POWER
 ==========================


	Source: Select one of the following possibilities:
	   1) Normalized to 1 (standard E grid): The source is normalized
		to 1 and the energy array consist in 500 points in the
		[1,100] keV interval.
	   2) Normalized to 1 (E grid from keyboard): The source is normalized
		to 1 and the energy starting point, ending point and
		number of points are entered from the keyboard (next entries).
		The number og points must be greater than one.
		For calculating a single energy point, set the starting
		and the ending value to the same value.
	   3) From external file: The energy [in eV] and source arrays
		are thetwo first columns of the given file.
		In the case that the file does not exist, it asks for
		a new one. Therefore, by entering any string (e.g. '?'),
		a browser to select the file will be launched.

	If selected source is case 2, then entry the start, end and
		number of E points.
	If selected source is 3, entry the file name.

	Number of elements: The number of optical elements for
		calculations (from 1 to 5).
		For each optical elements a line of entry boxes appear
		with the following meaning:

		xx oe formula: The optical element formula. This may be
		  an element or compound formula (i.e. Si, H2O, etc.), a
		  mixture formula (i.e.  H2O(0.99)Cl2(0.01)), or a
		  material name as defined in the DABAX file Compounds.dat
		  The list of the material defined in the installed
		  Compounds.dat file is listed below.
		  It is possible to type a question mark (?). In this case
		  the program will present a list with all the available
		  compounds in the Compounds.dat file, and the user must
		  select one. This avoids typos in typing the compound names.
		Filter/Mirror (select the appropiate entry).
		In the Flter case entry the filter thickness [mm]
		In the Mirror case entry the grazing angle [mrad] and
		  the surface roughness rms [Angstroms]
		Density: The density value in g/cm^3.
		    - Takes 1.0 as defaults in the other cases.




