May 22 – 28, 2011
Centre Bonlieu
Europe/Zurich timezone

Inclusive photon production at forward rapidities for pp collisions at √s = 0.9 TeV and 7 TeV in ALICE at the LHC

Not scheduled
Théâtre National (Centre Bonlieu)

Théâtre National

Centre Bonlieu

Board: 39
Poster Global and collective dynamics


Sudipan De (Variable Energy Cyclotron Centre (VECC)-Department of Atomic Ene)


We report the first measurement of the multiplicity and pseudorapidity distributions of photons in the pseudorapidity region of 2.3 < η < 3.9 in proton-proton collisions at center of mass energies of 0.9 TeV and 7 TeV at the LHC. The photon measurement is dominated by neutral pion decays and thus complimentary to those of the charged particles. Multiplicity distributions at both energies follow double Negative Binomial Distributions (NBD). We observe that the average photon multiplicity increases logarithmically with the beam energy. Photon multiplicity and pseudorapidity distributions for inelastic and non-single diffractive events are compared with results from event generators (Phojet, Pythia). Phojet is close to the data at 0.9 TeV, but both models under-predict the observed data at 7 TeV. Limiting fragmentation behavior is studied by combining with measurements from other experiments and then compared to the models.

Primary author

Sudipan De (Variable Energy Cyclotron Centre (VECC)-Department of Atomic Ene)

Presentation materials