Changeset abf7eed in sasview
- Timestamp:
- Oct 23, 2013 11:27:23 AM (11 years ago)
- Branches:
- master, ESS_GUI, ESS_GUI_Docs, ESS_GUI_batch_fitting, ESS_GUI_bumps_abstraction, ESS_GUI_iss1116, ESS_GUI_iss879, ESS_GUI_iss959, ESS_GUI_opencl, ESS_GUI_ordering, ESS_GUI_sync_sascalc, costrafo411, magnetic_scatt, release-4.1.1, release-4.1.2, release-4.2.2, release_4.0.1, ticket-1009, ticket-1094-headless, ticket-1242-2d-resolution, ticket-1243, ticket-1249, ticket885, unittest-saveload
- Children:
- 44f7c1b
- Parents:
- 1c1b037
- Location:
- src/sans/models/media
- Files:
-
- 3 edited
-
img/image004.PNG (modified) (previous)
-
img/image180.PNG (modified) (previous)
-
model_functions.html (modified) (10 diffs)
Legend:
- Unmodified
- Added
- Removed
-
src/sans/models/media/model_functions.html
r5777106 rabf7eed 33 33 <p>The 1D scattering intensity is calculated in the following way (Guinier, 1955):</p> 34 34 <p style="text-align: center;" align="center"><span style="position: relative; top: 16pt;"><img src="img/image004.PNG" alt="" /></span></p> 35 <p>where scale is a scale factor* volume fraction, V is the volume of the scatterer, r is the radius of the sphere, bkg is the background level and sldXXX is the scattering length density (SLD) of the scatterer or the solvent.</p>36 <p>Note that if your data is in absolute scale, the 'scale' should represent the volume fraction (unitless) if you have a good fit. If not, it should represent the volume fraction * a factor (by which your data might need to be rescaled).</p>37 <p>The 2D scattering intensity is the same as P(q)above, regardless of the orientation of the q vector.</p>35 <p>where r is the radius of the sphere, bkg is the background level and sldXXX is the scattering length density (SLD) of the scatterer or the solvent.<\p> 36 <p>Note that if your data is on an absolute scale, the 'scale' should represent the volume fraction (unitless) * volume of a scatterer, V.</p> 37 <p>The 2D scattering intensity is the same as above, regardless of the orientation of the q vector.</p> 38 38 <p>The returned value is scaled to units of [cm-1] and the parameters of the sphere model are the following:</p> 39 39 <div align="center"> … … 115 115 <p style="text-align: center; page-break-after: avoid;" align="center"> </p> 116 116 <p>Figure 1: Comparison of the DANSE scattering intensity for a sphere with the output of the NIST SANS analysis software. The parameters were set to: Scale=1.0, Radius=60 Å, Contrast=1e-6 Å -2, and Background=0.01 cm -1.</p> 117 <p style="margin-left: 0.25in;"><i>2013/09/09 - Description reviewed by King, S. and Parker, P.</i></p> 117 118 <p style="margin-left: 0.55in; text-indent: -0.3in;"><b><span style="font-size: 14pt;">2.2.</span></b><b><span style="font-size: 7pt;"> </span></b><a name="BinaryHSModel"></a><b><span style="font-size: 14pt;">BinaryHSModel</span></b></p> 118 119 <p>This model (binary hard sphere model) provides the scattering intensity, for binary mixture of spheres including hard sphere interaction between those particles. Using Percus-Yevick closure, the calculation is an exact multi-component solution:</p> … … 4805 4806 <tr style="height: 19.25pt;"> 4806 4807 <td style="border-width: medium 1pt 1pt; width: 107pt; height: 19.25pt;" valign="top" width="143"> 4807 <p>exponent_ l(=n)</p>4808 <p>exponent_p (=n)</p> 4808 4809 </td> 4809 4810 <td style="border-width: medium 1pt 1pt medium; width: 107pt; height: 19.25pt;" valign="top" width="143"> </td> … … 4814 4815 <tr style="height: 19.25pt;"> 4815 4816 <td style="border-width: medium 1pt 1pt; width: 107pt; height: 19.25pt;" valign="top" width="143"> 4816 <p>exponent_ p(=m)</p>4817 <p>exponent_l (=m)</p> 4817 4818 </td> 4818 4819 <td style="border-width: medium 1pt 1pt medium; width: 107pt; height: 19.25pt;" valign="top" width="143"> </td> … … 4839 4840 <p style="margin-left: 0.25in; text-align: center;" align="center"> </p> 4840 4841 <p style="margin-left: 0.25in;">Reference: None.</p> 4842 <p style="margin-left: 0.25in;"><i>2013/09/09 - Description reviewed by King, S. and Parker, P.</i></p> 4841 4843 <p style="margin-left: 0.55in; text-indent: -0.3in;"><b><span style="font-size: 14pt;">3.3.</span></b><b><span style="font-size: 7pt;"> </span></b><b><span style="font-size: 14pt;"> <a name="CorrLength"></a>CorrLength (CorrelationLengthModel)</span></b></p> 4842 4844 <p style="margin-left: 0.25in;">Calculate an empirical functional form for SANS data characterized by a low-Q signal and a high-Q signal</p> … … 4893 4895 <tr style="height: 19.25pt;"> 4894 4896 <td style="border-width: medium 1pt 1pt; vertical-align: top; width: 107pt; height: 19.25pt;"> 4895 <p>exponent_ l(=n)</p>4897 <p>exponent_p (=n)</p> 4896 4898 </td> 4897 4899 <td style="border-width: medium 1pt 1pt medium; width: 107pt; height: 19.25pt;" valign="top" width="143"> </td> … … 4902 4904 <tr style="height: 19.25pt;"> 4903 4905 <td style="border-width: medium 1pt 1pt; width: 107pt; height: 19.25pt;" valign="top" width="143"> 4904 <p>exponent_ p(=m)</p>4906 <p>exponent_l (=m)</p> 4905 4907 </td> 4906 4908 <td style="border-width: medium 1pt 1pt medium; width: 107pt; height: 19.25pt;" valign="top" width="143"> </td> … … 4928 4930 <p style="margin-left: 0.25in;">REFERENCE</p> 4929 4931 <p style="margin-left: 0.25in;">B. Hammouda, D.L. Ho and S.R. Kline, “Insight into Clustering in Poly(ethylene oxide) Solutions”, Macromolecules 37, 6932-6937 (2004).</p> 4932 <p style="margin-left: 0.25in;"><i>2013/09/09 - Description reviewed by King, S. and Parker, P.</i></p> 4930 4933 <p style="margin-left: 0.55in; text-indent: -0.3in;"><b><span style="font-size: 14pt;">3.4.</span></b><b><span style="font-size: 7pt;"> </span></b><b><span style="font-size: 14pt;"> <a name="Lorentz"></a>(Ornstein-Zernicke) Lorentz (Model)</span></b></p> 4931 4934 <p style="text-indent: 0.25in;">The Ornstein-Zernicke model is defined by:</p> … … 5055 5058 <p style="margin-left: 0.5in;"> </p> 5056 5059 <p style="margin-left: 0.5in;">Debye, Bueche, "Scattering by an Inhomogeneous Solid", J. Appl. Phys. 20, 518 (1949).</p> 5060 <p style="margin-left: 0.25in;"><i>2013/09/09 - Description reviewed by King, S. and Parker, P.</i></p> 5057 5061 <p style="margin-left: 0.55in; text-indent: -0.3in;"><b><span style="font-size: 14pt;">3.6.</span></b><b><span style="font-size: 7pt;"> </span></b><b><span style="font-size: 14pt;"> <a name="Absolute Power_Law"></a>Absolute Power_Law </span></b></p> 5058 5062 <p style="margin-left: 0.25in;">This model describes a power law with background.</p> … … 5385 5389 <p style="margin-left: 0.25in;">References:</p> 5386 5390 <p style="margin-left: 0.25in; text-indent: 0.25in;">D. Mildner, and P. Hall, J. Phys. D.: Appl. Phys., 19, 1535-1545 (1986), Equation(9).</p> 5391 <p style="margin-left: 0.25in;"><i>2013/09/09 - Description reviewed by King, S. and Parker, P.</i></p> 5387 5392 <p> </p> 5388 5393 <p> </p>
Note: See TracChangeset
for help on using the changeset viewer.
