Added delta_p_over_p plots

Added delta p over p tracking/scripts/rec_central_electrons.cxx

tracking/central_electrons.sh

@@ -69,9 +69,9 @@ popd
 pwd
 mkdir -p results/tracking
 
-root -b -q "tracking/scripts/rec_central_electrons.cxx(\"${JUGGLER_DETECTOR}/${JUGGLER_REC_FILE}\")"
+root -b -q "tracking/scripts/rec_central_electrons.cxx+(\"${JUGGLER_DETECTOR}/${JUGGLER_REC_FILE}\")"
 if [[ "$?" -ne "0" ]] ; then
-  echo "ERROR running juggler"
+  echo "ERROR running root script"
   exit 1
 fi