diff --git a/notebooks/Timepix/Compute_Timepix_Event_Centroids.ipynb b/notebooks/Timepix/Compute_Timepix_Event_Centroids.ipynb
index 506a84eb1c325b05b10747ce3827c35961b816ff..6fba05e2cdd8f111866a32f34cc359bb7bbaf5a8 100755
--- a/notebooks/Timepix/Compute_Timepix_Event_Centroids.ipynb
+++ b/notebooks/Timepix/Compute_Timepix_Event_Centroids.ipynb
@@ -204,6 +204,7 @@
     "        \"x\": np.array([]),\n",
     "        \"y\": np.array([]),\n",
     "        \"toa\": np.array([]),\n",
+    "        \"tot\": np.array([]),\n",
     "        \"tot_avg\": np.array([]),\n",
     "        \"tot_max\": np.array([]),\n",
     "        \"size\": np.array([]),\n",