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arXiv · 1411.4963

Measurement of the forward charged particle pseudorapidity density in pp collisions at sqrt(s) = 8 TeV using a displaced interaction point

The TOTEM Collaboration·G. Antchev·P. Aspell·I. Atanassov·V. Avati·J. Baechler·V. Berardi·M. Berretti·E. Bossini·U. Bottigli·M. Bozzo·E. Brücken·A. Buzzo·F. S. Cafagna·M. G. Catanesi·C. Covault·M. Csanád·T. Csörgő·M. Deile·M. Doubek·K. Eggert·V. Eremin·F. Ferro·A. Fiergolski·F. Garcia·V. Georgiev·S. Giani·L. Grzanka·J. Hammerbauer·J. Heino·T. Hilden·A. Karev·J. Kašpar·J. Kopal·V. Kundrát·S. Lami·G. Latino·R. Lauhakangas·T. Leszko·E. Lippmaa·J. Lippmaa·M. V. Lokajíček·L. Losurdo·M. Lo Vetere·F. Lucas Rodríguez·M. Macrí·T. Mäki·A. Mercadante·N. Minafra·S. Minutoli·F. Nemes·H. Niewiadomski·E. Oliveri·F. Oljemark·R. Orava·M. Oriunno·K. Österberg·P. Palazzi·Z. Peroutka·J. Procházka·M. Quinto·E. Radermacher·E. Radicioni·F. Ravotti·E. Robutti·L. Ropelewski·G. Ruggiero·H. Saarikko·A. Scribano·J. Smajek·W. Snoeys·J. Sziklai·C. Taylor·N. Turini·V. Vacek·J. Welti·J. Whitmore·P. Wyszkowski·K. Zielinski
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Abstract

The pseudorapidity density of charged particles dN(ch)/deta is measured by the TOTEM experiment in pp collisions at sqrt(s) = 8 TeV within the range 3.9 < eta < 4.7 and -6.95 < eta < -6.9. Data were collected in a low intensity LHC run with collisions occurring at a distance of 11.25 m from the nominal interaction point. The data sample is expected to include 96-97\% of the inelastic proton-proton interactions. The measurement reported here considers charged particles with p_T > 0 MeV/c, produced in inelastic interactions with at least one charged particle in -7 < eta < -6 or 3.7 < eta <4.8 . The dN(ch)/deta has been found to decrease with |eta|, from 5.11 +- 0.73 at eta = 3.95 to 1.81 +- 0.56 at eta= - 6.925. Several MC generators are compared to the data and are found to be within the systematic uncertainty of the measurement.

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The TOTEM Collaboration, G. Antchev, P. Aspell, I. Atanassov, V. Avati, J. Baechler, V. Berardi, M. Berretti, E. Bossini, U. Bottigli, M. Bozzo, E. Brücken, A. Buzzo, F. S. Cafagna, M. G. Catanesi, C. Covault, M. Csanád, T. Csörgő, M. Deile, M. Doubek, K. Eggert, V. Eremin, F. Ferro, A. Fiergolski, F. Garcia, V. Georgiev, S. Giani, L. Grzanka, J. Hammerbauer, J. Heino, T. Hilden, A. Karev, J. Kašpar, J. Kopal, V. Kundrát, S. Lami, G. Latino, R. Lauhakangas, T. Leszko, E. Lippmaa, J. Lippmaa, M. V. Lokajíček, L. Losurdo, M. Lo Vetere, F. Lucas Rodríguez, M. Macrí, T. Mäki, A. Mercadante, N. Minafra, S. Minutoli, F. Nemes, H. Niewiadomski, E. Oliveri, F. Oljemark, R. Orava, M. Oriunno, K. Österberg, P. Palazzi, Z. Peroutka, J. Procházka, M. Quinto, E. Radermacher, E. Radicioni, F. Ravotti, E. Robutti, L. Ropelewski, G. Ruggiero, H. Saarikko, A. Scribano, J. Smajek, W. Snoeys, J. Sziklai, C. Taylor, N. Turini, V. Vacek, J. Welti, J. Whitmore, P. Wyszkowski, K. Zielinski. 2014-11-18. Measurement of the forward charged particle pseudorapidity density in pp collisions at sqrt(s) = 8 TeV using a displaced interaction point. https://arxiv.org/abs/1411.4963

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