diff --git a/tracking/particles.py b/tracking/particles.py
index 4378745f0bb80048aa21b266f3c674bf8df3c144..43cb87359cdcdfa352e360f1fa32219b979b50f2 100644
--- a/tracking/particles.py
+++ b/tracking/particles.py
@@ -546,7 +546,7 @@ class Beam:
             for current in filling_pattern:
                 if current != 0:
                     bunch_list.append(Bunch(self.ring, mp_per_bunch, 
-                                            current_per_bunch, track_alive))
+                                            current, track_alive))
                 elif current == 0:
                     bunch_list.append(Bunch(self.ring, alive=False))
         else: