II. Outstanding research and other results in 2016
II/a Outstanding research and other results
Hadron physics.  — We measured the production of Z-jet pairs for the first time in pp and central
Pb-Pb collisions at a center-of-mass energy per nucleon pair of 5.02 TeV. The Z-jet azimuthal angle correlations and transverse momentum imbalance show changes in agreement with expected jet quenching effects. We have also measured the spectra of charged particles at a center-of-mass energy per nucleon pair of 5.02 TeV using Pb-Pb and pp data. The nuclear modification factor in the 5% most central collisions shows a maximal suppression by a factor of 7–8 in the transverse momentum region of 6–9 GeV. This dip is followed by an increase, which continues up to the highest momenta measured. These data were compared to theoretical predictions and earlier experimental results at lower collision energies.

We have studied the production of charged pions, kaons and (anti)protons at mid-rapidity in p-Pb collisions, also at 5.02 TeV. At intermediate transverse momentum the proton-to-pion ratio increases with multiplicity, a similar effect is not present in the kaon-to-pion ratio. The structure of such increase is qualitatively similar to those observed in pp and heavy-ion collisions. The (anti)proton nuclear modification factor shows a Cronin-like enhancement, while pions and kaons show little or no nuclear modification.

II/B Relationship between science and society
Members of the research group participated in the organisation of  the following events: International Particle Physics Masterclasses, Wigner-CERN Open Days, Multi-colored physics bus.

V. List of important publications in 2015
1. CMS Collaboration, Study of Z boson production in pPb collisions at √sNN = 5.02 TeV, Phys Lett B 759 (2016) 36-57; IF=6.131
2. CMS Collaboration, Measurement of long-range near-side two-particle angular correlations in pp collisions at √s = 13 TeV, Phys Rev Lett 116 (2016) 032301; IF=7.512
3. ALICE Collaboration, Multiplicity dependence of charged pion, kaon, and (anti)proton production at large transverse momentum in p–Pb collisions at √sNN = 5.02 TeV, Phys Lett B 760 (2016) 720-735; IF=6.131