dc.description.abstract | Cross sections for the coherent photoproduction of ρ
0 vector mesons in ultraperipheral Pb-Pb collisions at √
sNN = 5.02 TeV are reported. The measurements, which
rely on the π
+π
− decay channel, are presented in three regions of rapidity covering the
range |y| < 0.8. For each rapidity interval, cross sections are shown for different nuclearbreakup classes defined according to the presence of neutrons measured in the zero-degree
calorimeters. The results are compared with predictions based on different models of nuclear shadowing. Finally, the observation of a coherently produced resonance-like structure
with a mass around 1.7 GeV/c
2 and a width of about 140 MeV/c
2
is reported and compared
with similar observations from other experiments. | en |