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McStas: Brilliance_monitor Component

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

The Brilliance_monitor Component

Special "Brilliance" monitor.


  • Author: Peter Willendrup, derived from TOF_lambda_monitor.comp
  • Origin: DTU Physics
  • Date: May 23, 2012
  • Version:(Unknown)


If used in the right setting, will output "instantaneous" and "mean" brilliances in units of Neutrons/cm^2/ster/AA/s. Conditions for proper units:
  • Use a with a source of area 1x1cm
  • The source must illuminate/focus to an area of 1x1cm a 1m distance
  • Parametrise the Brilliance_monitor with the frequency of the source
  • To not change the source TOF distribution, place the Brilliance monitor close to the source!
with a source of area 1x1cm illuminating/focusing to an area of 1x1cm a 1m distance, this monitor will output "instantaneous" and "mean" brilliances in units of Neutrons/cm^2/ster/AA/s Here is an example of the use of the component. Note how the mentioned Unit conditions are implemented in instrument code. COMPONENT Source = ESS_moderator_long( l_low = lambdamin, l_high = lambdamax, dist = 1, xw = 0.01, yh = 0.01, freq = 14, T=50, tau=287e-6, tau1=0, tau2=20e-6, n=20, n2=5, d=0.00286, chi2=0.9, I0=6.9e11, I2=27.6e10, branch1=0, branch2=0.5, twopulses=0, size=0.01) AT (0, 0, 0) RELATIVE Origin COMPONENT BRIL = Brilliance_monitor(nlam=196,nt=401,filename="bril.sim", t_0=0,t_1=4000,lambda_0=lambdamin, lambda_1=lambdamax, Freq=14) AT (0,0,0.000001) RELATIVE Source

Input parameters

Parameters in boldface are required; the others are optional.
Name Unit Description Default
nlam 1 Number of bins in wavelength 101
nt 1 Number of bins in TOF 1001
nowritefile 1 If set, monitor will skip writing to disk 0
lambda_0 AA Minimum wavelength detected 0
lambda_1 AA Maximum wavelength detected 20
restore_neutron 1 If set, the monitor does not influence the neutron state 0
Freq Hz Source frequency. Use freq=1 for reactor source  
tofcuts 1 Flag to generate TOF-distributions as function of wavelength 0
toflambda 1 Flag to generate TOF-lambda distribution output 0
xwidth m width of monitor 0.01
yheight m height of monitor 0.01
source_dist m Distance from source. Beware when transporting through neutron optics! 1
t_0 us Minimum time 0
t_1 us Maximum time 20000
srcarea cm^2 Source area 1


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

Generated automatically by McDoc, Peter Willendrup <> / Wed Jan 12 15:13:20 2022

Last Modified: Wednesday, 12-Jan-2022 16:13:20 CET
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