[ Identification | Description | Input parameters | Output parameters | Links ]
Source_div
ComponentThe routine is a rectangular neutron source, which has a gaussian or uniform divergent output in the forward direction. The neutron energy is uniformly distributed between E0-dE and E0+dE or a wavelength is uniformly distributed between Lambda0-dLambda and Lambda0+dLambda. If energy and wavelength are given, energy is used. In the case of uniform distribution (gauss=0), angles are uniformly distributed between -hdiv and +hdiv as well as -vdiv and +vdiv. For Gaussian distribution (gauss=1), 'hdiv' and 'vdiv' define the FWHM of a Gauss'schen distribution, Example: Source_div(width=0.1, height=0.1, hdiv=2, vdiv=2, E0=14, dE=2, gauss=0) %VALIDATION Feb 2005: tested by Kim Lefmann (o.k.) Apr 2005: energy distribution used in external tests of Fermi choppers (o.k.) Jun 2005: wavelength distribution used in external tests of velocity selectors (o.k.) Validated by: K. Lieutenant %BUGS distribution is uniform in (hor. and vert.) angle (relative to moderator normal), therefore not suited for large angles
Name | Unit | Description | Default |
---|---|---|---|
width | m | Width of source | |
height | m | Height of source | |
hdiv | deg | FWHM (Gaussian) or maximal (uniform) horizontal divergence | |
vdiv | deg | FWHM (Gaussian) or maximal (uniform) vertical divergence | |
E0 | meV | Mean energy of neutrons. | 0.0 |
dE | meV | Energy spread of neutrons. | 0.0 |
Lambda0 | Ang | Mean wavelength of neutrons (only relevant for E0=0) | 0.0 |
dLambda | Ang | Wavelength spread of neutrons. | 0.0 |
gauss | - | Criterion: 0: uniform, 1: Gaussian distribution (default) | 1 |
Name | Unit | Description | Default |
---|---|---|---|
sigmah | rad | parameter 'sigma' of the Gaussian distribution for horizontal divergence | |
sigmav | rad | parameter 'sigma' of the Gaussian distribution for vertical divergence | |
p_init | - | normalisation factor 1/'neutron_count' |
Source_div.comp
.
[ Identification | Description | Input parameters | Output parameters | Links ]
Generated automatically by McDoc, Peter Willendrup <peter.willendrup@risoe.dk> / Wed Dec 10 13:38:46 2008