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[ Identification  Description  Input parameters  Output parameters  Links ] The
Based on a perfect crystal component by: Miguel A. Gonzalez, A. Dianoux June 2013 (ILL)
Changelog:
Version 1.1
 BUGFIX: correct neutron energy shift in Doppler mode
 added option 'debyescherrer' to select analyzer geometry
 added option 'facette' to approximate analyzer sphere by small, flat crystals
Version 1.0
 inital release

Name  Unit  Description  Default 

ttmin  NAN  
ttmax  deg  analyzer coverage angle in horizontal xzplane between 180 and 180  NAN 
tt0  only if centerfocus==1  [deg] angular center position in the horizontal plane  NAN 
ttwidth  deg  horizontal coverage as center and full width  NAN 
width  m  absolute width  NAN 
phimin  NAN  
phimax  180 and 180 if debyescherrer==1  [deg] vertical analyzer coverage between 90 and 90  NAN 
phi0  only if centerfocus==1  [deg] angular vertical position  NAN 
phiwidth  deg  vertical coverage as center and full width  NAN 
height  only if debyescherrer==0  [m] absolute height  NAN 
debyescherrer  180...180  (0/1) bend analyzer following a DebyeScherrer ring along scattering angle tt (twotheta) (phi =  0 
facette  m  width of square crystal facettes arranged on the spherical surface (set 0 to disable). Default: 0 Warning: Facettation will fail at the poles along +y axis.  0 
facette_xi  deg  random misalignemt of each facette. Default: 0  0 
centerfocus  0/1  Component origin is the center of the analyzer sphere if 1, if set to 0 the origin is on the analyzer surface. Default: 0  0 
radius  m  Radius of curvature, set to 0 for a flat surface. Default: 0  0 
tau  sometimes also called Q...  [A^1] Scattering vector of the reflex  NAN 
lambda  A  Alternatively to tau: backscattered wavelength  NAN 
R0  1.0  
dtauovertau  1  Plateau width of the Ewald/Darwin curve (see  NAN 
dtauovertau_ext  randomized for each trajectory, full width  [] Relative variation of tau  0 
ewald  Ewald  [0/1] Use Ewald curve if 1, Darwin curve if 0. Default: 1  1 
sigma  The width will be transformed and the Gaussian is actually calculated in kspace.  [meV] Width of the Gaussian reflectivity curve in meV (corresponding to the energy resolution).  NAN 
ismirror  0/1  Simply reflect all neutrons if 1. Good for debugging/visualization. Default: 0  0 
speed  m/s  Maximum Doppler speed. The actual monochromator velocity is randomized between speed and +speed. Default: 0  0 
amplitude  m  Amplitude of the Doppler movement. Default: 0  0 
smartphase  0/1  Optimize Doppler phase for better MC efficiency if set to 1. *WARNING:* Experimental option! Always compare to a simulation without smartphase. Better do not use smartwidth with Ewald/Darwin curves due to their endless tails. Default: 0  0 
smartwidth  meV  Half width of the possible energy reflection window for smartphase. Default: 5*sigma OR 10*2*dtauovertau*E0  NAN 
exclusive  0/1  If set to 1, absorb all neutrons that missed the monochromator/analyzer surface. Default: 0  0 
transmit  0...1  MonteCarlo probability of transmitting an event through the monochromator/analyzer surface. (Events with R=1.0 for DarwinE/Ewald curves are always reflected!). Default: 0  0 
verbose  0 
PerfectCrystal.comp
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[ Identification  Description  Input parameters  Output parameters  Links ]
Generated automatically by McDoc, Peter Willendrup <peter.willendrup@risoe.dk> / Tue May 26 13:03:59 2020