[ Identification | Description | Input parameters | Links ]

The SNS_source Component

A source that produces a time and energy distribution from the SNS moderator files

Identification

• Site:
• Author: G. Granroth
• Origin: SNS Project Oak Ridge National Laboratory
• Date: July 2004

Description

Produces a time-of-flight spectrum from SNS moderator files
moderator files can be obtained from the SNS website .
IMPORTANT: The output units of this component are N/pulse
IMPORTANT: The component needs a FULL PATH to the source input file
Notes:
(1) the raw moderator files are per Sr.  The focusing parameters provide the solid
angle accepted by the guide to remove the Sr dependence from the output. Therefore
the best practice is to set focus_xw and focus_yh to the width and height of the next beam
component, respectively. The dist parameter should then be set as the distance
from the moderator to the first component.
(2) This component works purely by interpolation. Therefore be sure that Emin and
Emax are within the limits of the moderator file

Input parameters

Parameters in boldface are required; the others are optional.

Name	Unit	Description	Default
filename		Filename of source data
xwidth	m	width of moderator	0.1
yheight	m	height of moderator	0.12
dist	m	Distance from source to the focusing rectangle
focus_xw
focus_yh	m	Height of focusing rectangle
Emin	meV	minimum energy of neutron to generate
Emax	meV	maximum energy of neutron to generate

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

Links

• Source code for SNS_source.comp.

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[ Identification | Description | Input parameters | Links ]

Generated on 2025-05-08 13:31:31

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