[Fix] Sign of the dipolar wake potential

Fix the sign of the dipolar wake potential to get the correct sign of the tune shift in tracking with respect to the impedance/wake function conventions used in mbtack2.

tracking/wakepotential.py

@@ -276,10 +276,10 @@ class WakePotential(Element):
             Wp = signal.convolve(profile0, W0*-1, mode='same')*dtau0
         elif wake_type == "Wxdip":
             dipole0 = self.dipole_moment(bunch, "x", tau0)
-            Wp = signal.convolve(profile0*dipole0, W0*-1, mode='same')*dtau0
+            Wp = signal.convolve(profile0*dipole0, W0, mode='same')*dtau0
         elif wake_type == "Wydip":
             dipole0 = self.dipole_moment(bunch, "y", tau0)
-            Wp = signal.convolve(profile0*dipole0, W0*-1, mode='same')*dtau0
+            Wp = signal.convolve(profile0*dipole0, W0, mode='same')*dtau0
         else:
             raise ValueError("This type of wake is not taken into account.")