Changeset f67ed10 in sasview for calculatorview/src/sans/perspectives

Timestamp:

Aug 18, 2011 7:02:23 PM (13 years ago)

Author:

Jae Cho <jhjcho@…>

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:

83bf44e1

Parents:

b470477

Message:

updated help doc and wave pulse shapes(TOF)

Location:

calculatorview/src/sans/perspectives/calculator/media

Files:

• q.gif (added)
• resolution_calculator_help.html (modified) (2 diffs)
• resolution_tutor.gif (modified) (previous)
• sigma_q.gif (added)
• sigma_table.gif (added)

calculatorview/src/sans/perspectives/calculator/media/resolution_calculator_help.html

@@ -3 +3 @@
 <h4>SANS Q Resolution Estimator</h4>
 <ul>
-<li><a href="#Description">Description:</a></li>
+<li><a href="#Description">Description</a></li>
 <li><a href="#HowTo">HowTo?</a></li>
-
+<li><a href="#Theory">Theory</a></li>
 </ul>
 <h5><a name="Description">Description</a></h5>
@@ -17 +17 @@
 <h5><a name="HowTo">HowTo?</a></h5>
 <p>
-1. Change the default values of the instrumental parameters as desired,
-and type the qx and qy value where the resolution
-is calculated. 
+1. Select the source and source type (Monochromatic or TOF). 
+Note that the computational difference between the sources is 
+only the gravitational contribution due to the mass.</p>
+<p>
+2. Change the default values of the instrumental parameters as desired.</p>
+<p>
+3. The input formats of wavelength and its spread (=FWHM/wavelength) depend on the source type.
+<li>For monochromatic wave, the inputs are just one values as shown with the defaults.</li>
+<li>For TOF, the min and max values should be separated by "-" to describe the wavelength band range.
+Optionally, the input of the wavelength (NOT of the wavelength spread) 
+could be extended by adding "; ##" where the ## is the number 
+of the bins for the numerical integration.
+Otherwise, the default value "10" bins will be used. 
+The same number of bins will be used for the corresponding wavelength spread in either cases.</li>
 </p>
+<p>4. For TOF, the default wavelength spectrum is flat. 
+The custom spectrum file (with 2 column text: wavelength(A) vs. intensity) 
+can also be loaded by selecting "Add new" in the combobox.</p>
 <p>
-2. Select the coordinate system from the radio button.
-</p>
-<p>
-3. Click on the compute button.
+5. Once set all the input values, click the compute button. 
+Depending on computation loads the calculation time will vary.
 </p>
 <p> 
-4. 1D and 2D dQ will be displayed in the text-box at the bottom of 
+6. 1D and 2D dQ will be displayed in the text-box at the bottom of 
 the panel. Two dimensional resolution weight distribution 
 (2D elliptical Gaussian function) will also be 
 displayed in the plot panel even if the Q inputs are outside 
 of the detector limit.
-The red lines indicate the limits of the detector. 
+The red lines indicate the limits of the detector (if a green lines appear (for TOF), 
+it indicates the limits of the maximum q range for the largest wavelength 
+due to the size of the detector).
+The summary can be accessed by clicking the 'light-bulb' icon 
+at the bottom of the SansView main window.
 </p>
 <p><img src="resolution_tutor.gif">
+</p>
+<h5><a name="Theory">Theory</a></h5>
+<p>
+The scattering wave transfer vector is by definition,</p>
+<p>
+<img src="q.gif" width="600" height="300">
+</p>
+<p>In the limit of the small angle, the variance of q in the first order approximation is</p>
+<p>
+<img src="sigma_q.gif">
+</p>
+In summary, the geometric and gravitational contributions depending on the shape of each factors can be expressed  
+as shown the table.</p>
+<p>
+<img src="sigma_table.gif">
+</p>
+<p>
+Finally, we use a Gaussian function to describe the 2D weighting distribution of the uncertainty in q.
 </p>
 </body>