diff --git a/mbtrack2/tracking/particles.py b/mbtrack2/tracking/particles.py
index 9dfd6910fb1baa41950d9dea10eaf7b4b3063740..e663ee0ac563c871951452098a1d4565a1226237 100644
--- a/mbtrack2/tracking/particles.py
+++ b/mbtrack2/tracking/particles.py
@@ -119,12 +119,12 @@ class Bunch:
             current = 0
         self._mp_number = int(mp_number)
         
-        self.dtype = np.dtype([('x',np.float),
-                       ('xp',np.float),
-                       ('y',np.float),
-                       ('yp',np.float),
-                       ('tau',np.float),
-                       ('delta',np.float)])
+        self.dtype = np.dtype([('x', float),
+                       ('xp', float),
+                       ('y', float),
+                       ('yp', float),
+                       ('tau', float),
+                       ('delta', float)])
         
         self.particles = np.zeros(self.mp_number, self.dtype)
         self.track_alive = track_alive
diff --git a/mbtrack2/tracking/rf.py b/mbtrack2/tracking/rf.py
index aa4eb68562a3165ba2a3e2f81d19dbcde970670d..69a1c20f28f74503f9a11ab24ccc68a187418086 100644
--- a/mbtrack2/tracking/rf.py
+++ b/mbtrack2/tracking/rf.py
@@ -200,8 +200,8 @@ class CavityResonator():
         self.detune = detune
         self.Vc = Vc
         self.theta = theta
-        self.beam_phasor = np.zeros(1, dtype=np.complex)
-        self.beam_phasor_record = np.zeros((self.ring.h), dtype=np.complex)
+        self.beam_phasor = np.zeros(1, dtype=complex)
+        self.beam_phasor_record = np.zeros((self.ring.h), dtype=complex)
         self.tracking = False
         self.Vg = 0
         self.theta_g = 0