[ Identification | Description | Input parameters | Links ]

The Moderator Component

A simple pulsed source for time-of-flight.

Identification

• Site:
• Author: KN, M.Hagen
• Origin: Risoe
• Date: August 1998

Description

Produces a simple time-of-flight spectrum, with a flat energy distribution

Example: Moderator(radius = 0.0707, dist = 9.035, focus_xw = 0.021, focus_yh = 0.021, Emin = 10, Emax = 15, Ec = 9.0, t0 = 37.15, gamma = 39.1)

Input parameters

Parameters in boldface are required; the others are optional.

Name	Unit	Description	Default
radius	m	Radius of source	0.07
Emin	meV	Lower edge of energy distribution
Emax	meV	Upper edge of energy distribution
dist	m	Distance from source to the focusing rectangle	0
focus_xw	m	Width of focusing rectangle	0.02
focus_yh	m	Height of focusing rectangle	0.02
t0	mus	decay constant for low-energy neutrons	37.15
Ec	meV	Critical energy, below which the flux decay is constant	9.0
gamma	meV	energy dependence of decay time	39.1
target_index	1	relative index of component to focus at, e.g. next is +1 this is used to compute 'dist' automatically.	+1
flux	1/(s cm 2 st meV)	flux	1

AT (	,	,		) RELATIVE		Generate
ROTATED (	,	,		) RELATIVE

Links

• Source code for Moderator.comp.

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[ Identification | Description | Input parameters | Links ]

Generated on mcstas 3.5.32

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Last Modified: Monday, 30-Jun-2025 11:05:09 CEST