Optimized amplitude factors for wake function calculations.

mbtrack2/impedance/resistive_wall.py

@@ -172,8 +172,8 @@ class CircularResistiveWall(WakeField):
             idx2 = time == 0
             idx3 = np.logical_not(np.logical_or(idx1, idx2))
             idx4 = np.isclose(0, time, atol=atol)
-            factor = 4 * self.Z0 * c / (np.pi * self.radius**2) * self.length
-            wl[idx2] = 0.25 * factor
+            factor = self.Z0 * c / (3 * np.pi * self.radius**2) * self.length
+            wl[idx2] = 3 * factor
             wl[idx3] = self.__LongWakeExact(time[idx3], factor)
             wl[idx4] *= 0.5
         else:
@@ -220,8 +220,8 @@ class CircularResistiveWall(WakeField):
         if exact == True:
             idx2 = time == 0
             idx3 = np.logical_not(np.logical_or(idx1, idx2))
-            factor = ((8 * self.Z0 * c**2 * self.t0) / (np.pi * self.radius**4) *
-                  self.length)
+            factor = ( (self.Z0 * c**2 * self.t0) / (3 * np.pi * self.radius**4) *
+                  self.length )
             wt[idx3] = self.__TransWakeExact(time[idx3], factor)
         else:
             idx2 = np.logical_not(idx1)
@@ -229,7 +229,7 @@ class CircularResistiveWall(WakeField):
         return wt
 
     def __LongWakeExact(self, t, factor):
-        wl = np.real(factor / 12 * ( 4 * np.exp(-1 * t / self.t0)
+        wl = np.real( factor * ( 4 * np.exp(-1 * t / self.t0)
             * np.cos(np.sqrt(3) * t / self.t0)
             + wofz(1j * np.sqrt(2 * t / self.t0))
             - wofz(np.exp(1j * np.pi / 6) * np.sqrt(2 * t / self.t0))
@@ -237,7 +237,7 @@ class CircularResistiveWall(WakeField):
         return wl
 
     def __TransWakeExact(self, t, factor):
-        wt = np.real(factor / 24 * ( 2 * np.exp(-1 * t / self.t0)
+        wt = np.real( factor * ( 2 * np.exp(-1 * t / self.t0)
             * ( np.sqrt(3) * np.sin(np.sqrt(3) * t / self.t0)
             - np.cos(np.sqrt(3) * t / self.t0) )
             + wofz(1j * np.sqrt(2 * t / self.t0))