Measurement of the forward charged-particle pseudorapidity density in pp collisions at √s = 7 TeV with the TOTEM experiment

G. Antchev, P. Aspell, I. Atanassov, V. Avati, J. Baechler, V. Berardi, M. Berretti, E. Bossini, M. Bozzo, P. Brogi, E. Brücken, A. Buzzo, F. S. Cafagna, M. Calicchio, M. G. Catanesi, C. Covault, M. Csanád, T. Csörg, M. Deile, K. EggertV. Eremin, R. Ferretti, F. Ferro, A. Fiergolski, F. Garcia, S. Giani, V. Greco, L. Grzanka, J. Heino, T. Hilden, M. R. Intonti, J. Kašpar, J. Kopal, V. Kundrát, K. Kurvinen, S. Lami, G. Latino, R. Lauhakangas, T. Leszko, E. Lippmaa, M. Lokajíček, M. Lo Vetere, F. Lucas Rodríguez, M. MacRí, L. Magaletti, T. Mäki, A. Mercadante, N. Minafra, S. Minutoli, F. Nemes, H. Niewiadomski, E. Oliveri, F. Oljemark, R. Orava, M. Oriunno, K. Österberg, P. Palazzi, J. Procházka, M. Quinto, E. Radermacher, E. Radicioni, F. Ravotti, E. Robutti, L. Ropelewski, G. Ruggiero, H. Saarikko, A. Santroni, A. Scribano, W. Snoeys, J. Sziklai, C. Taylor, N. Turini, V. Vacek, M. Vitek, J. Welti, J. Whitmore

Research output: Article

30 Citations (Scopus)


The TOTEM experiment has measured the charged-particle pseudorapidity density dN ch/dη in pp collisions at for 5.3<|η|<6.4 in events with at least one charged particle with transverse momentum above 40 MeV/c in this pseudorapidity range. This extends the analogous measurement performed by the other LHC experiments to the previously unexplored forward η region. The measurement refers to more than 99% of non-diffractive processes and to single and double diffractive processes with diffractive masses above ∼3.4 GeV/c 2, corresponding to about 95% of the total inelastic cross-section. The dN ch/dη has been found to decrease with |η|, from 3.84 ± 0.01(stat) ± 0.37(syst) at |η|=5.375 to 2.38±0.01(stat)±0.21(syst) at |η|=6.375. Several MC generators have been compared to data; none of them has been found to fully describe the measurement.

Original languageEnglish
Article number31002
Issue number3
Publication statusPublished - máj. 1 2012


ASJC Scopus subject areas

  • Physics and Astronomy(all)

Cite this

Antchev, G., Aspell, P., Atanassov, I., Avati, V., Baechler, J., Berardi, V., Berretti, M., Bossini, E., Bozzo, M., Brogi, P., Brücken, E., Buzzo, A., Cafagna, F. S., Calicchio, M., Catanesi, M. G., Covault, C., Csanád, M., Csörg, T., Deile, M., ... Whitmore, J. (2012). Measurement of the forward charged-particle pseudorapidity density in pp collisions at √s = 7 TeV with the TOTEM experiment. EPL, 98(3), [31002].