LHC Seminar

Recent ALICE results on Pb-Pb and p-Pb Ultra Peripheral Collisions

by Evgeny Kryshen (CERN)

Tuesday, 17 December 2013 from to (Europe/Zurich)
at CERN ( 503-1-001 - Council Chamber )
The strong electromagnetic fields surrounding the Pb-ions acceleratedat the LHC allow two-photon, photon-proton and photon-lead interactions to be studied in a new kinematic regime. These interactions can be studied in ultra-peripheral collisions,where the impact parameters are larger than the sum of the nuclear radii and hadronic interactions are suppressed. During the lead-lead runs at the LHC in 2010 and 2011, and during the proton-lead run in 2013, the ALICE experiment implemented dedicated triggers to select ultra-peripheral collisions. Based on signals from the Muon spectrometer, the Time-of-Flight detector, the Silicon Pixel detector, and the VZERO scintillator array. The cross section for photoproduction of J/Psi mesons at mid- and forward-rapidities in Pb-Pb collisions will be presented. 
The results will be compared to model calculations and their implications for the study of nuclear gluon shadowing will be discussed. First results on J/Psi photoproduction in p-Pb collisions will also be discussed and compared with previous measurements and QCD based models.
Webcast Please note that this event will be available live via the Webcast Service.
Organised by M. Mangano, C. Lourenco, G. Unal......................... **Tea and Coffee will be served at 10h30**