[ Identification | Description | Input parameters | Links ]

The Spot_sample Component

Spot sample.

Identification

• Site:
• Author: Garrett Granroth
• Origin: Oak Ridge National Laboratory
• Date: 14.11.14

Description

A sample that is a series of delta functions in omega and Q.  The Q is
determined by a two theta value and an equal number of spots around the
beam center.  This component is a variation of the V sample written
by Kim Lefmann and Kristian Nielsen.  The following text comes from their
original component.
A Double-cylinder shaped incoherent scatterer (a V-sample)
No multiple scattering. Absorbtion included.
The shape of the sample may be a box with dimensions xwidth, yheight, zthick.
The area to scatter to is a disk of radius 'focus_r' situated at the target.
This target area may also be rectangular if specified focus_xw and focus_yh
or focus_aw and focus_ah, respectively in meters and degrees.
The target itself is either situated according to given coordinates (x,y,z), or
setting the relative target_index of the component to focus at (next is +1).
This target position will be set to its AT position. When targeting to centered
components, such as spheres or cylinders, define an Arm component where to
focus at.

Example: spot_sample(radius_o=0.01, h=0.05, pack = 1,
xwidth=0, yheight=0, zthick=0, Eideal=100.0,w=50.0,two_theta=25.0,n_spots=4)

Input parameters

Parameters in boldface are required; the others are optional.

Name	Unit	Description	Default
radius_o	m	Outer radius of sample in (x,z) plane	0.01
h	m	Height of sample y direction	0.05
pack	1	Packing factor	1
xwidth	m	horiz. dimension of sample, as a width	0
yheight	m	vert.. dimension of sample, as a height	0
zthick	m	thickness of sample	0
Eideal	meV	The presumed incident energy	100.0
w	meV	The energy transfer of the delta function	50.0
two_theta	degrees	the scattering angle of the spot	25.0
n_spots	1	The number of spots to generate symmetrically around the beam	4

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

Links

• Source code for Spot_sample.comp.

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[ Identification | Description | Input parameters | Links ]

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Last Modified: Monday, 30-Jun-2025 11:05:10 CEST