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McStas: Source_Maxwell_3

[ Identification | Description | Input parameters | Links ]

The Source_Maxwell_3 Component

Source with up to three Maxwellian distributions


  • Site:
  • Author: Kim Lefmann
  • Origin: Risoe
  • Date: March 2001


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.
sizemEdge of cube shaped source (for backward compatibility)0
yheightmHeight of rectangular source0
xwidthmWidth of rectangular source0
LminAALower edge of lambda distribution
LmaxAAUpper edge of lambda distribution
distmDistance from source to focusing rectangle; at (0,0,dist)
focus_xwmWidth of focusing rectangle
focus_yhmHeight of focusing rectangle
T1K1st temperature of thermal distribution
T2K2nd temperature of thermal distribution300
T3K3nd temperature of - - -300
I11/(cm**2*st)flux, 1 (in flux units, see above)
I21/(cm**2*st)flux, 2 (in flux units, see above)0
I31/(cm**2*st)flux, 3 - - -0
target_index1relative index of component to focus at, e.g. next is +1 this is used to compute 'dist' automatically.+1
lambda0AAMean wavelength of neutrons.0
dlambdaAAWavelength spread of neutrons.0


[ Identification | Description | Input parameters | Links ]

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

Last Modified: Tuesday, 16-Apr-2024 20:05:21 CEST
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