22-27 March 2015
Hotel do Bosque
Brazil/East timezone

## Inclusive photon production at forward rapidities in pp collisions at LHC energies with the ALICE experiment

26 Mar 2015, 18:00
30m
Hotel do Bosque

#### Hotel do Bosque

Rodovia Mário Covas (Rio-Santos) BR - 101 Sul, Km 533, Angra dos Reis, RJ, Brazil
Oral presentation Relativistic heavy-ion reactions - new data, analyses and models

### Speaker

Dr Sudipan De (USP)

### Description

Measurements of multiplicity and pseudorapidity distributions of particles produced in pp collisions are important for the study of particle production mechanisms and to obtain baseline distributions to be compared with those from heavy-ion collisions. The inclusive photon measurements (dominated by $\pi^{0}$ decays) are complementary to the charged particle measurements. The present work focuses on the forward rapidity region with comparisons to different models such as PYTHIA and PHOJET. We report the measurements of multiplicity and pseudorapidity distributions of inclusive photons using the ALICE Photon Multiplicity Detector (PMD) at forward rapidities (2.3$<\eta<$3.9) in pp collisions at $\sqrt{s}$ = 0.9, 2.76 and 7 TeV. It is observed that the photon multiplicity distributions are well described by negative binomial distributions (NBD). Multiplicity distributions are studied in terms of KNO variables for each energy. It is shown that the increase in the average photon multiplicity as a function of beam energy is compatible with both a logarithmic and power law dependence. The results are compared to different model predictions. These models reproduce experimental results at lower energy while they are not accurate at higher energies.

### Primary author

Dr Sudipan De (USP)

### Presentation Materials

 sudipan_de.pdf sudipan_de.ppt