Comparing particle production in Pb–Pb and p–Pb collisions with pp collisions provides insight into the longitudinal (and low-x) nature of the hot and dense medium created in heavy-ion collisions. Investigating the system-size dependence of the particle production at the same collision energy is particularly important, as one can then directly study effects of the nuclear geometry. ALICE has unique coverage which can be exploited at forward rapidity. The Forward Multiplicity and the Silicon Pixel Detectors can measure charged particles over a wide range of−3.4< η <5.0. On the other hand, the Photon Multiplicity Detector can measure neutral-particle production over a kinematic range of 2.3< η <3.9. Results across different colliding systems at forward rapidity will be presented for both charged and neutral particles. The measurements will be compared with model calculations based on different particle-production mechanisms and initial conditions. Finally, we will show the evolution of the width of the pseudorapidity density distribution with centrality and give a lower bound on the Bjorken energy density for different colliding systems.
|Collaboration / Activity||ALICE|