Study of the PYTHIA $\Delta\eta\Delta\phi$ correlation as a function of   multiplicity and transverse sphericity in proton-proton collisions at 7 TeV
  The study and understanding of the details of proton-proton collisions is important since they are the benchmark for the comparison with heavy ion results. In the present work we have studied the $\Delta\eta\Delta\phi$ correlations as a function of the event multiplicity and transverse sphericity in pp collisions at $\sqrt{s}$ = 7 TeV using PYTHIA 8.180. The results show large variation in the shape of the correlation as a function of the sphericity and multiplicity indicating the importance of slicing the data in bins of both observables to better understand the complexity of the interactions. Motivated by the radial flow patterns originated by color reconnection (CR), results with and without CR together with dihadron correlations are discussed. 
Edgar Perez, Guy Paic, Antonio Ortiz, Eleazar Cuautle
hep-ph nucl-ex