Update FluxInjection3D benchmark

Regression/Checksum/benchmarks_json/FluxInjection3D.json

@@ -1,21 +1,39 @@
 {
-  "electron": {
-    "particle_momentum_x": 1.1192116199394354e-18,
-    "particle_momentum_y": 2.238114590066897e-18,
-    "particle_momentum_z": 1.1156457989239732e-18,
-    "particle_position_x": 102495.14197173176,
-    "particle_position_y": 188132.22608016344,
-    "particle_position_z": 102423.13701045913,
+  "lev=0": {},
+  "electron_negative": {
+    "particle_momentum_x": 1.1222699783863554e-18,
+    "particle_momentum_y": 1.1202176725070554e-18,
+    "particle_momentum_z": 1.3925955132362978e-18,
+    "particle_position_x": 102352.09026544492,
+    "particle_position_y": 102418.88243172191,
+    "particle_position_z": 194298.7949373403,
     "particle_weight": 8.959999999999998e-07
   },
-  "lev=0": {},
   "proton": {
-    "particle_momentum_x": 3.835423016604918e-15,
-    "particle_momentum_y": 2.0468371931479925e-15,
-    "particle_momentum_z": 2.055186547721331e-15,
-    "particle_position_x": 189256.1546041931,
-    "particle_position_y": 102293.00576740496,
-    "particle_position_z": 102314.93877691089,
+    "particle_momentum_x": 3.8338884590187296e-15,
+    "particle_momentum_y": 2.0442156829943128e-15,
+    "particle_momentum_z": 2.045804260395492e-15,
+    "particle_position_x": 189238.69249885075,
+    "particle_position_y": 102242.91543133644,
+    "particle_position_z": 102297.92915049737,
+    "particle_weight": 8.959999999999998e-07
+  },
+  "electron": {
+    "particle_momentum_x": 1.1150196665556376e-18,
+    "particle_momentum_y": 2.2311586451156107e-18,
+    "particle_momentum_z": 1.1115069298757383e-18,
+    "particle_position_x": 102477.68142952351,
+    "particle_position_y": 188137.20906834095,
+    "particle_position_z": 102443.44417709563,
+    "particle_weight": 8.959999999999998e-07
+  },
+  "proton_negative": {
+    "particle_momentum_x": 2.051429985038282e-15,
+    "particle_momentum_y": 2.053711846305655e-15,
+    "particle_momentum_z": 2.7212135003240815e-15,
+    "particle_position_x": 102307.73649638034,
+    "particle_position_y": 102475.13878406698,
+    "particle_position_z": 193638.89296895845,
     "particle_weight": 8.959999999999998e-07
   }
 }