Changeset 60

Timestamp:

Mar 21, 2007 12:05:19 PM (16 years ago)

Author:

srkline

Message:

resolution calculation now uses the projected area of the beamstop for the shadowing factor and all other resolution calculations. per JGB 3/21/07 ticket 751

File:

• sans/SANSReduction/trunk/Put in User Procedures/SANS_Reduction_v5.00/WriteQIS.ipf (modified) (2 diffs)

sans/SANSReduction/trunk/Put in User Procedures/SANS_Reduction_v5.00/WriteQIS.ipf

@@ -547 +547 @@
 // Incorporates eqn. 3-15 from J. Appl. Cryst. (1995) v. 28 p105-114
 //
+// - 21 MAR 07 uses projected BS diameter on the detector
+//
 Function/S getResolution(inQ,lambda,lambdaWidth,DDet,apOff,S1,S2,L1,L2,BS,del_r,SigmaQ,QBar,fSubS)
         Variable inQ, lambda, lambdaWidth, DDet, apOff, S1, S2, L1, L2, BS, del_r
@@ -580 +582 @@
         L2 *= 100.0
         L2 += apOff
-
-        BS *= 0.5*0.1                   //convert to radius and [cm]
         del_r *= 0.1                            //width of annulus, convert mm to [cm]
+        
+        BS *= 0.5*0.1                   //nominal BS diameter passed in, convert to radius and [cm]
+        // 21 MAR 07 SRK - use the projected BS diameter, based on a point sample aperture
+        Variable LB
+        LB = 20.1 + 1.61*BS                     //distance in cm from beamstop to anode plane (empirical)
+        BS = bs + bs*lb/(l2-lb)         //adjusted diameter of shadow from parallax
         
         //Start resolution calculation