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McStas: Conics_PP

[ Identification | Description | Input parameters | Links ]

The Conics_PP Component


  • Site:
  • Author: Peter Wilendrup and Erik Knudsen
    (derived from Giacomo Resta skeleton-component)
  • Origin: DTU
  • Date:


Implements a set of nshells Wolter I Paraboloid/Parabolid pairs using conics.h from ConicTracer.

The component has two distinct modes of specifying the geometry:
a) Via the radii vector, parametrized from largest to smallest radius with a length of 'nshells'

b) By specifying radii rmax and rmin, between which a quadratic law distributes 'nshells' surfaces.

The mirrors are assumed to be touching at the mid-optic plane, i.e. there is no gap between primary
and secondary mirror.
By definition the ratio between primary and secondary mirror glancing angles is 1/3.
At present a single m-value is used for all mirrors.

Input parameters

Parameters in boldface are required; the others are optional.
rminmMidoptic plane radius of innermost mirror pair.0.0031416
rmaxmMidoptic plane radius of outermost mirror pair.0.05236
focal_length_umFocal length of upstream mirror.10.070
focal_length_dmFocal length of downstream mirror.10.070
lp1mUpstream paraboloid mirror length.0.84
lp2mDownstream paraboloid mirror length.0.84
nshells1Number of nested shells to expect4
m1Critical angle of mirrors as multiples of Ni.1
mirr_thickmThickness of mirror shell surfaces - NOT YET IMPLEMENTED0
disk Flag. If nonzero, insert a disk to block the central area within the innermost mirror.1
radiimOptional vector of radii (length should match nshells)NULL
R01Reflectivity at Low angles for reflectivity curve approximation0.99
QcAA-1Critical scattering vector0.021
WAA-1Width of supermirror cut-off0.003
alphaAASlope of reflectivity for reflectivity curve approximation6.07
transmit1Fraction of statistics to assign to transmitted beam - NOT YET IMPLEMENTED0


[ Identification | Description | Input parameters | Links ]

Generated on 2023-09-19 20:01:36

Last Modified: Wednesday, 03-Jan-2024 19:59:10 CET
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