[ Identification | Description | Input parameters | Links ]

The SANS_Guinier Component

Identification

• Site:
• Author: Henrich Frielinghaus
• Origin: FZ-Juelich/FRJ-2/IFF/KWS-2
• Date: Sept 2004

Description

Sample that scatters with a Guinier shape. This is just an example where analytically
an integral exists. The neutron paths are proportional to the intensity
(low intensity > few paths).

Guinier function (Rg)
a = Rg*Rg/3
propability_unscaled = q * exp(-a*q*q)
integral_prop_unscal = 1/(2*a) * (1 - exp(-a*q*q))
propability_scaled   = 2*a * q*exp(-a*q*q) / (1 - exp(-a*q*q))
integral_prop_scaled = (1 - exp(-a*q*q)) / (1 - exp(-a*qmax*qmax))

In this simulation method many paths occur for high propability.
For simulation of low intensities see SANS_AnySamp.

Sample components leave the units of flux for the probability
of the individual paths. That is more consitent than the
Sans_spheres routine. Furthermore one can simulate the
transmitted beam. This allows to determine the needed size of
the beam stop. Only absorption has not been included yet to
these sample-components. But thats really nothing.

Example: SANS_Guinier(transm=0.5, Rg=100, qmax=0.03, xwidth=0.01, yheight=0.01, zdepth=0.001)

Input parameters

Parameters in boldface are required; the others are optional.

Name	Unit	Description	Default
transm	1	(coherent) transmission of sample for the optical path "zdepth"	0.5
Rg	Angs	Radius of Gyration	100
qmax	AA-1	Maximum scattering vector	0.03
xwidth	m	horiz. dimension of sample, as a width	0.01
yheight	m	vert.. dimension of sample, as a height	0.01
zdepth	m	thickness of sample	0.001

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

Links

• Source code for SANS_Guinier.comp.
• Sans_spheres component

---

[ Identification | Description | Input parameters | Links ]

Generated on 2023-09-19 20:01:36

---

Last Modified: Tuesday, 17-Sep-2024 05:31:13 CEST