Muon::MuonLayerHoughTool::CollectionsPerSector Node1 Muon::MuonLayerHoughTool ::CollectionsPerSector + sector Node2 std::vector< RegionHashVec > Node2->Node1 +technologyRegionHashVecs Node3 std::vector< T > Node3->Node2 +elements Node4 T Node4->Node3 +elements