The `SNS_source_analytic` Component

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

Identification

Site:
Author: F. X. Gallmeier
Origin: SNS Oak Ridge National Laboratory
Date: October 18, 2010

Description

Produces a time-of-flight spectrum from SNS moderator files
moderator files can be obtained from the author
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 parameters focus_xw focus_yh and dist
provide the solid angle with which the beam line is served.
The best practice is to set focus_xw and focus_yh to the width and height of the
closest beam component, and dist as the distance from the moderator
location to this component.
(2) Be sure that Emin and Emax are within the limits of 1e-5 to 100 eV
(3) the proton pulse length T determines short- and long-pulse mode

Beamport definitions:
BL11: a1Gw2-11-f5_fit_fit.dat
BL14: a1Gw2-14-f5_fit_fit.dat
BL17: a1Gw2-17-f5_fit_fit.dat
BL02: a1Gw2-2-f5_fit_fit.dat
BL05: a1Gw2-5-f5_fit_fit.dat
BL08: a1Gw2-8-f5_fit_fit.dat

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 (default 0.1 m)	0.10
yheight	m	height of moderator (default 0.12 m)	0.12
dist	m	Distance from source to the focusing rectangle (no default)
focus_xw	m	Width of focusing rectangle (no default)
focus_yh	m	Height of focusing rectangle (no default)
Emin	meV	minimum energy of neutrons (default 0.01 meV)	0.01
Emax	meV	maximum energy of neutrons (default 1e5 meV)	1.0e5
tinmin	us	minimum time of neutrons (default 0 us)	0.0
tinmax	us	maximum time of neutrons (default 2000 us)	2000.0
sample_E		sample energy from: (default 0)	0
sample_t		sample t from: (default 0)	0
proton_T	us	proton pulse length (0 us)	0.0
p_power	MW	proton power (default 2 MW)	2.0
n_pulses		number of pulses (default 1)	1.0

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

The SNS_source_analytic Component

Identification

Description

Input parameters

Links

The `SNS_source_analytic` Component