Status of the TOTEM experiment at LHC

J. Baechler, G. Antchev, P. Aspell, I. Atanassov, V. Avati, V. Berardi, M. Berretti, E. Bossini, M. Bozzo, P. Brogi, E. Brücken, A. Buzzo, F. Cafagna, M. Calicchio, M. G. Catanesi, C. Covault, T. Csörgo, M. Deile, K. Eggert, V. EreminR. 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, 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, G. Sanguinetti, A. Santroni, A. Scribano, W. Snoeys, J. Sziklai, C. Taylor, N. Turini, V. Vacek, M. Vítek, J. Welti, J. Whitmore

Research output: Contribution to journalArticle


The TOTEM experiment is dedicated to the measurement of the total proton-proton cross-section with the luminosity-independent method and the study of elastic and diffractive scattering processes. Two tracking telescopes, T1 and T2, integrated in the CMS detector, cover the pseudo-rapidity region between 3.1 and 6.5 on both sides of the interaction point IP5. The Roman Pot (RP) stations are located at distances of ±147m and ±220 m with respect to the interaction point to measure the very forward scattered protons at very small angles. During the LHC technical stop in winter 2010/2011, the TOTEM experiment was completed with the installation of the T1 telescope and the RP stations at ±147 m. In 2011, the LHC machine provided special optics with the large ß*=90 m, allowing TOTEM to measure the elastic scattering differential cross-section, down to the four-momentum transfer squared |t|=2×10-2 GeV2. Using the optical theorem and extrapolation of the differential cross-section to t=0 (optical point), the total p-p crosssection at the LHC energy of √s = 7 TeV could be computed for the first time. Furthermore we measured with standard LHC beam optics and the energy of √s = 7 TeV the forward charged particle pseudorapidity density dn/dZ in the range of 5.3<|η|<6.4. The status of the experiment, the performance of the detectors with emphasis on the RPs are described and the first physics results are presented.

Original languageEnglish
Pages (from-to)21-25
Number of pages5
JournalNuclear Instruments and Methods in Physics Research, Section A: Accelerators, Spectrometers, Detectors and Associated Equipment
Publication statusPublished - Jan 1 2013



  • Edgeless Si detector
  • Elastic scattering
  • GEM
  • Roman Pot
  • Total cross-section

ASJC Scopus subject areas

  • Nuclear and High Energy Physics
  • Instrumentation

Cite this

Baechler, J., Antchev, G., Aspell, P., Atanassov, I., Avati, V., Berardi, V., Berretti, M., Bossini, E., Bozzo, M., Brogi, P., Brücken, E., Buzzo, A., Cafagna, F., Calicchio, M., Catanesi, M. G., Covault, C., Csörgo, T., Deile, M., Eggert, K., ... Whitmore, J. (2013). Status of the TOTEM experiment at LHC. Nuclear Instruments and Methods in Physics Research, Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, 718, 21-25.