some more info, and replacing the parameter half-thickness through the film thickness

src/tests/MeissnerNonMuSR/PMeissnerNonMuSR.cpp

@@ -57,10 +57,14 @@ PMeissnerNonMuSR::~PMeissnerNonMuSR()
 
 //------------------------------------------------------
 /**
- * <p>Example  of a user defined function. This example implements a 3rd order polynom
- * \f[ = \sum_{k=0}^3 c_k t^k\f]
+ * <p>Example of a thin film Meissner screening user function (\f$B_{\rm G}\f$ versus \f$\langle z \rangle\f$).
  *
- * <b>meaning of paramValues:</b> \f$c_0\f$, \f$c_1\f$, \f$c_2\f$, \f$c_3\f$
+ * \f[ B_{\rm G}(\langle z \rangle\) = B_0 \cosh((t-d-[z-d])/\lambda_{ab}) / \cos((t-d)/\lambda_{ab}) \f]
+ *
+ * - \f$B_{\rm G}\f$ is the screened field value obtained from a Gaussian fit
+ * - \f$\langle z \rangle\f$ is the mean muon stopping range obtained from trim.sp.
+ *
+ * <b>meaning of param:</b> \f$B_0\f$, \f$2 t\f$ = film thickness, \f$d\f$ = dead layer thickness, \f$\lambda_{ab}\f$
  *
  * <b>return:</b> function value
  *
@@ -69,15 +73,15 @@ PMeissnerNonMuSR::~PMeissnerNonMuSR()
  */
 Double_t PMeissnerNonMuSR::operator()(Double_t z, const std::vector<Double_t> &param) const
 {
-  // expected parameters: Bext, t=thickness/2, deadLayer, lambda_ab
+  // expected parameters: Bext, t=thickness, deadLayer, lambda_ab
 
   assert(param.size() == 4);
 
-  // if z<deadLayer or z>2t-deadLayer
+  // if z<deadLayer or z>2tt-deadLayer
+  Double_t tt = param[1]/2.0;
   Double_t result = param[0];
-  if ((z > param[2]) && (z < 2.0*param[1]-param[2]))
-    result = param[0]*cosh((param[1]-param[2]-(z-param[2]))/param[3])/cosh((param[1]-param[2])/param[3]);
-
+  if ((z > param[2]) && (z < param[1]-param[2]))
+    result = param[0]*cosh((tt-z)/param[3])/cosh((tt-param[2])/param[3]);
 
   return result;
 }

src/tests/MeissnerNonMuSR/README

@@ -0,0 +1,25 @@
+$Id$
+
+This is a simple example for a Meissner screening user function for non-muSR input for musrfit.
+
+It is very simple and has the following parameters:
+
+1. field, i.e. external field value
+2. thickness
+3. dead layer thickness
+4. lambda_ab
+
+The following function are needed to geht the needed ROOT shared library:
+
+Makefile.PMeissnerNonMuSR
+PMeissnerNonMuSR.cpp
+PMeissnerNonMuSR.h
+PMeissnerNonMuSRLinkDef.h  <- this header is needed to generate the dictionary stub
+
+The following files are examples how to generate the needed parameter input files, and how
+to analyze it
+
+runlist.txt         <- used together with msr2data to add the zMean data into the db-file
+YBCO-Meissner.db    <- db-file generate with msr2data by using runlist.txt
+YBCO-Meissner.msr   <- msr-file used to fit B versus zMean
+

src/tests/MeissnerNonMuSR/YBCO-Meissner.msr

@@ -3,7 +3,7 @@ YBCO Meissner
 FITPARAMETER
 #      Nr. Name        Value     Step      Pos_Error  Boundaries
          1 field       100.0     1.0       none       0         none      
-         2 thickness   150.0     0.0       none
+         2 halfThick   300.0     0.0       none
          3 deadLayer   15.0       1.0       none       0         none
          4 lambda      150.0     0.1       none       0         none