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McStas: Source_Maxwell_3 Component

[ Identification | Description | Input parameters | Output parameters | Links ]

The Source_Maxwell_3 Component

Source with up to three Maxwellian distributions


  • Author: Kim Lefmann
  • Origin: Risoe
  • Date: March 2001
  • Version:(Unknown)


A parametrised continuous source for modelling a (cubic) source
with (up to) 3 Maxwellian distributions.
The source produces a continuous spectrum.
The sampling of the neutrons is uniform in wavelength.

Units of flux: neutrons/cm^2/second/ster
(McStas units are in general neutrons/second)

Example:  PSI cold source T1=150.42 K / 2.51 AA     I1 = 3.67 E11
                          T2=38.74 K / 4.95 AA      I2 = 3.64 E11
                          T3=14.84 K / 9.5 AA       I3 = 0.95 E11

Input parameters

Parameters in boldface are required; the others are optional.
Name Unit Description Default
size for backward compatibility [m] Edge of cube shaped source 0
yheight m Height of rectangular source 0
xwidth m Width of rectangular source 0
Lmin AA Lower edge of lambda distribution  
Lmax AA Upper edge of lambda distribution  
dist 0,0,dist [m] Distance from source to focusing rectangle; at  
focus_xw m Width of focusing rectangle  
focus_yh m Height of focusing rectangle  
T1 K 1st temperature of thermal distribution  
T2 K 2nd temperature of thermal distribution 300
T3 K 3nd temperature of - - - 300
I1 in flux units, see above [1/(cm**2*st)] flux, 1  
I2 in flux units, see above [1/(cm**2*st)] flux, 2 0
I3 1/(cm**2*st) flux, 3 - - - 0
target_index 1 relative index of component to focus at, e.g. next is +1 this is used to compute 'dist' automatically. +1
lambda0 AA Mean wavelength of neutrons. 0
dlambda AA Wavelength spread of neutrons. 0

Output parameters

Name Unit Description Default


[ Identification | Description | Input parameters | Output parameters | Links ]

Generated automatically by McDoc, Peter Willendrup <> / Tue May 26 13:03:59 2020

Last Modified: Tuesday, 26-May-2020 15:03:59 CEST
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