Add J/psi resolution; re-write RC with Dummy instead of rc tracks

include/util.h

@@ -80,7 +80,7 @@ namespace util {
   //=====================================================================================
   inline auto p_dummy(const std::vector<eic::ReconstructedParticle>& parts)
   {
-    std::vector<ROOT::Math::PxPyPzMVector> momenta{tracks.size()};
+    std::vector<ROOT::Math::PxPyPzMVector> momenta{parts.size()};
     // transform our raw tracker info into proper 4-momenta
     std::transform(parts.begin(), parts.end(), momenta.begin(), [](const auto& parts) {
       const double px = parts.p.x;