About McStas
Conditions of use
Authors/Contacts
Project funding
Download
Components
Other Downloads (share)
Documentation
Wiki (GitHub)
McStas manual
Publications
14.5 The SNS_source_analytic McStas Component
A source that produces a time and energy distribution from parameterized SNS moderator files
Identification
-
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="probability distribution", 1="energy range", 2="lambda range", 3="log(energy) range" |
0 |
|
sample_t |
|
sample t from: (default 0) 0="probability distribution", 1="time range" |
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 |
|
|
|||
|
|
|||
|
|
|||
Links
-
Component source code found in file SNS_source_analytic.comp.
