E. Radicioni

Large-angle production of charged pions with 3-12.9 GeV/c incident protons on nuclear targets

M.G. Catanesi, E. Radicioni, R. Edgecock, M. Ellis, ∗ F.J.P. Soler, C. Gößling, S. Bunyatov, A. Krasnoperov, B. Popov, † V. Serdiouk, V. Tereschenko, E. Di Capua, G. Vidal–Sitjes, ‡ A. Artamonov, § S. Giani, S. Gilardoni, P. Gorbunov, § A. Grant, A. Grossheim, ¶ A. Ivanchenko, ∗∗ V. Ivanchenko, †† A. Kayis-Topaksu, ‡‡ J. Panman, I. Papadopoulos, E. Tcherniaev, I. Tsukerman, § R. Veenhof, C. Wiebusch, §§ P. Zucchelli, ¶¶ A. Blondel, S. Borghi, M.C. Morone, ∗∗∗ G. Prior, † † † R. Schroeter, C. Meurer, U. Gastaldi, G. B. Mills, ‡ ‡ ‡ J.S. Graulich, §§§ G. Grégoire, M. Bonesini, ¶¶¶ F. Ferri, M. Kirsanov, A. Bagulya, V. Grichine, N. Polukhina, V. Palladino, L. Coney, ‡ ‡ ‡ D. Schmitz, ‡ ‡ ‡ G. Barr, A. De Santo, F. Bobisut, D. Gibin, A. Guglielmi, M. Mezzetto, J. Dumarchez, U. Dore, D. Orestano, F. Pastore, A. Tonazzo, L. Tortora, C. Booth, L. Howlett, G. Skoro, M. Bogomilov, M. Chizhov, D. Kolev, R. Tsenov, S. Piperov, P. Temnikov, M. Apollonio, P. Chimenti, G. Giannini, J. Burguet–Castell, A. Cervera–Villanueva, J.J. Gómez–Cadenas, J. Mart́ın–Albo, P. Novella, M. Sorel, and A. Tornero (HARP Collaboration)

Measurement of the production of charged pions by protons on a tantalum target

A measurement of the double-differential cross-section for the production of charged pions in proton–tantalum collisions emitted at large angles from the incoming beam direction is presented. The data were taken in 2002 with the HARP detector in the T9 beam line of the CERN PS. The pions were produced by proton beams in a momentum range from 3xa0GeV/c to 12xa0GeV/c hitting a tantalum target with a thickness of 5% of a nuclear interaction length. The angular and momentum range covered by the experiment (100xa0MeV/c ≤p< 800xa0MeV/c and 0.35xa0rad ≤θ< 2.15xa0rad) is of particular importance for the design of a neutrino factory. The produced particles were detected using a small-radius cylindrical time projection chamber (TPC) placed in a solenoidal magnet. Track recognition, momentum determination and particle identification were all performed based on the measurements made with the TPC. An elaborate system of detectors in the beam line ensured the identification of the incident particles. Results are shown for the double-differential cross-sections d2σ/dpdθ at four incident proton beam momenta (3xa0GeV/c, 5xa0GeV/c, 8xa0GeV/c and 12xa0GeV/c). In addition, the pion yields within the acceptance of typical neutrino factory designs are shown as a function of beam momentum. The measurement of these yields within a single experiment eliminates most systematic errors in the comparison between rates at different beam momenta and between positive and negative pion production.

Large-angle production of charged pions by 3-12.9 GeV/c protons on beryllium, aluminium and lead targets

Measurements of the double-differential π± production cross-section in the range of momentum 100xa0MeV/c≤p<u2009800xa0MeV/c and angle 0.35xa0radu2009≤θ<u2009 2.15xa0rad in proton–beryllium, proton–aluminium and proton–lead collisions are presented. The data were taken with the HARP detector in the T9 beam line of the CERN PS. The pions were produced by proton beams in a momentum range from 3xa0GeV/c to 12.9xa0GeV/c hitting a target with a thickness of 5% of a nuclear interaction length. The tracking and identification of the produced particles was performed using a small-radius cylindrical time projection chamber (TPC) placed inside a solenoidal magnet. Incident particles were identified by an elaborate system of beam detectors. Results are obtained for the double-differential cross-sections d2σ/dpdθ at six incident proton beam momenta (3xa0GeV/c, 5xa0GeV/c, 8xa0GeV/c, 8.9xa0GeV/c (Be only), 12xa0GeV/c and 12.9xa0GeV/c (Al only)) and compared to previously available data.

Measurement of the production cross-sections of pi(+/-) in p-C and pi(+/-)-C interactions at 12 GeV/c

The results of the measurements of the double-differential production cross-sections of pions, dσ/dpdΩ, in p-C and π-C interactions using the forward spectrometer of the HARP experiment are presented. The incident particles are 12 GeV/c protons and charged pions directed onto a carbon target with a thickness of 5% of a nuclear interaction length. For p-C interactions the analysis is performed using 100 035 reconstructed secondary tracks, while the corresponding numbers of tracks for π-C and π-C analyses are 106 534 and 10 122 respectively. Cross-section results are presented in the kinematic range 0.5 GeV/c ≤ pπ < 8 GeV/c and 30 mrad ≤ θπ < 240 mrad in the laboratory frame. The measured cross-sections have a direct impact on the precise calculation of atmospheric neutrino fluxes and on the improved reliability of extensive air shower simulations by reducing the uncertainties of hadronic interaction models in the low energy range. HARP collaboration M.G. Catanesi, E. Radicioni Università degli Studi e Sezione INFN, Bari, Italy R. Edgecock, M. Ellis, S. Robbins, F.J.P. Soler Rutherford Appleton Laboratory, Chilton, Didcot, UK C. Gößling Institut für Physik, Universität Dortmund, Germany S. Bunyatov, A. Krasnoperov, B. Popov, V. Tereshchenko Joint Institute for Nuclear Research, JINR Dubna, Russia E. Di Capua, G. Vidal–Sitjes Università degli Studi e Sezione INFN, Ferrara, Italy A. Artamonov, S. Giani, S. Gilardoni, P. Gorbunov, A. Grant, A. Grossheim, P. Gruber, V. Ivanchenko, A. Kayis-Topaksu, J. Panman, I. Papadopoulos, E. Tcherniaev, I. Tsukerman, R. Veenhof, C. Wiebusch, P. Zucchelli CERN, Geneva, Switzerland A. Blondel, S. Borghi, M. Campanelli, M.C. Morone, G. Prior, R. Schroeter Section de Physique, Université de Genève, Switzerland R. Engel, C. Meurer Forschungszentrum Karlsruhe, Institut für Kernphysik, Karlsruhe, Germany I. Kato University of Kyoto, Japan U. Gastaldi Laboratori Nazionali di Legnaro dell’ INFN, Legnaro, Italy G. B. Mills Los Alamos National Laboratory, Los Alamos, USA J.S. Graulich, G. Grégoire Institut de Physique Nucléaire, UCL, Louvain-la-Neuve, Belgium M. Bonesini, F. Ferri Università degli Studi e Sezione INFN, Milano, Italy M. Kirsanov Institute for Nuclear Research, Moscow, Russia A. Bagulya, V. Grichine, N. Polukhina P. N. Lebedev Institute of Physics (FIAN), Russian Academy of Sciences, Moscow, Russia V. Palladino Università “Federico II” e Sezione INFN, Napoli, Italy L. Coney, D. Schmitz Columbia University, New York, USA G. Barr, A. De Santo, C. Pattison, K. Zuber Nuclear and Astrophysics Laboratory, University of Oxford, UK F. Bobisut, D. Gibin, A. Guglielmi, M. Mezzetto Università degli Studi e Sezione INFN, Padova, Italy J. Dumarchez, F. Vannucci LPNHE, Universités de Paris VI et VII, Paris, France U. Dore Università “La Sapienza” e Sezione INFN Roma I, Roma, Italy D. Orestano, F. Pastore, A. Tonazzo, L. Tortora Università degli Studi e Sezione INFN Roma III, Roma, Italy C. Booth, L. Howlett Dept. of Physics, University of Sheffield, UK M. Bogomilov, M. Chizhov, D. Kolev, R. Tsenov Faculty of Physics, St. Kliment Ohridski University, Sofia, Bulgaria S. Piperov, P. Temnikov Institute for Nuclear Research and Nuclear Energy, Academy of Sciences, Sofia, Bulgaria M. Apollonio, P. Chimenti, G. Giannini, G. Santin Università degli Studi e Sezione INFN, Trieste, Italy J. Burguet–Castell, A. Cervera–Villanueva, J.J. Gómez–Cadenas, J. Mart́ın–Albo, P. Novella, M. Sorel Instituto de F́ısica Corpuscular, IFIC, CSIC and Universidad de Valencia, Spain Now at FNAL, Batavia, Illinois, USA. Jointly appointed by Nuclear and Astrophysics Laboratory, University of Oxford, UK. Now at Codian Ltd., Langley, Slough, UK. Now at University of Glasgow, UK. Also supported by LPNHE, Universités de Paris VI et VII, Paris, France. Now at Imperial College, University of London, UK. ITEP, Moscow, Russian Federation. Permanently at Instituto de F́ısica de Cantabria, Univ. de Cantabria, Santander, Spain. Now at SpinX Technologies, Geneva, Switzerland. Now at TRIUMF, Vancouver, Canada. Now at University of St. Gallen, Switzerland. On leave of absence from Ecoanalitica, Moscow State University, Moscow, Russia. Now at Çukurova University, Adana, Turkey. Now at III Phys. Inst. B, RWTH Aachen, Aachen, Germany. On leave of absence from INFN, Sezione di Ferrara, Italy. Now at CERN, Geneva, Switzerland. Now at Univerity of Rome Tor Vergata, Italy. Now at Lawrence Berkeley National Laboratory, Berkeley, California, USA. K2K Collaboration. MiniBooNE Collaboration. Now at Section de Physique, Université de Genève, Switzerland, Switzerland. Now at Royal Holloway, University of London, UK. Now at University of Sussex, Brighton, UK. Now at ESA/ESTEC, Noordwijk, The Netherlands.

Large-angle production of charged pions with incident pion beams on nuclear targets

We gratefully acknowledge the help and support of the PS beam staff and of the numerous technical collaborators who contributed to the detector design, construction, commissioning and operation. In particular, we would like to thank G. Barichello, R. Brocard, K. Burin, V. Carassiti, F. Chignoli, D. Conventi, G. Decreuse, M. Delattre, C. Detraz, A. Domeniconi, M. Dwuznik, F. Evangelisti, B. Friend, A. Iaciofano, I. Krasin, D. Lacroix, J.-C. Legrand, M. Lobello, M. Lollo, J. Loquet, F. Marinilli, J. Mulon, L. Musa, R. Nicholson, A. Pepato, P. Petev, X. Pons, I. Rusinov, M. Scandurra, E. Usenko, and R. van der Vlugt, for their support in the construction of the detector. The collaboration acknowledges the major contributions and advice of M. Baldo-Ceolin, L. Linssen, M.T. Muciaccia and A. Pullia during the construction of the experiment. The collaboration is indebted to V. Ableev, P. Arce, F. Bergsma, P. Binko, E. Boter, C. Buttar, M. Calvi, M. Campanelli, C. Cavion, A. Chukanov, A. De Min, M. Doucet, D. Dullmann, R. Engel, V. Ermilova, W. Flegel, P. Gruber, Y. Hayato, P. Hodgson, A. Ichikawa, I. Kato, O. Klimov, T. Kobayashi, D. Kustov, M. Laveder, M. Mass, H. Meinhard, T. Nakaya, K. Nishikawa, M. Paganoni, F. Paleari, M. Pasquali, J. Pasternak, C. Pattison, M. Placentino, S. Robbins, G. Santin, V. Serdiouk, S. Simone, A. Tornero, S. Troquereau, S. Ueda, A. Valassi, F. Vannucci and K. Zuber for their contributions to the experiment and to P. Dini for help in MC production. nWe acknowledge the contributions of V. Ammosov, G. Chelkov, D. Dedovich, F. Dydak, M. Gostkin, A. Guskov, D. Khartchenko, V. Koreshev, Z. Kroumchtein, I. Nefedov, A. Semak, J. Wotschack, V. Zaets and A. Zhemchugov to the work described in this paper. nThe experiment was made possible by grants from the Institut Interuniversitaire des Sciences Nucleaires and the Interuniversitair Instituut voor Kernwetenschappen (Belgium), Ministerio de Educacion y Ciencia, Grant FPA2003-06921-c02-02 and Generalitat Valenciana, grant GV00-054-1, CERN (Geneva, Switzerland), the German Bundesministerium fur Bildung und Forschung (Germany), the Istituto Nazionale di Fisica Nucleare (Italy), INR RAS (Moscow), the Russian Foundation for Basic Research (grant 08-02-00018) and the Particle Physics and Astronomy Research Council (UK). We gratefully acknowledge their support. This work was supported in part by the Swiss National Science Foundation and the Swiss Agency for Development and Cooperation in the framework of the programme SCOPES - Scientific co-operation between Eastern Europe and Switzerland.

Large-angle production of charged pions by 3-GeV/c - 12-GeV/c protons on carbon, copper and tin targets

A measurement of the double-differential π± production cross-section in proton–carbon, proton–copper and proton–tin collisions in the range of pion momentum 100xa0MeV/c≤p<800xa0MeV/c and angle 0.35xa0rad≤θ<2.15xa0rad is presented. The data were taken with the HARP detector in the T9 beam line of the CERN PS. The pions were produced by proton beams in a momentum range from 3xa0GeV/c to 12xa0GeV/c hitting a target with a thickness of 5% of a nuclear interaction length. The tracking and identification of the produced particles was done using a small-radius cylindrical time projection chamber (TPC) placed in a solenoidal magnet. An elaborate system of detectors in the beam line ensured the identification of the incident particles. Results are shown for the double-differential cross-sections d2σ/dpdθ at four incident proton beam momenta (3xa0GeV/c, 5xa0GeV/c, 8xa0GeV/c and 12xa0GeV/c).

K/π production ratios from 450 GeV/c protons on beryllium

Abstract This paper reports on the charged K / π production ratios and on the shape of the p T distributions of π fluxes measured by the SPY/NA56 experiment for 450 GeV/c proton interactions on beryllium targets. The present data cover a secondary momentum range from 7 GeV/c to 135 GeV/c in the forward direction and with p T values up to 600 MeV/c. An experimental accuracy of about 3% has been achieved. These results will reduce the uncertainty on the estimation of the ν e component of neutrino beams.

Forward production of charged pions with incident protons on nuclear targets at the CERN Proton Synchrotron

Measurements of the double-differential π production cross-section in the range of momentum 0.5 GeV/c ≤ p ≤ 8.0 GeV/c and angle 0.025 rad ≤ θ ≤ 0.25 rad in collisions of protons on beryllium, carbon, nitrogen, oxygen, aluminium, copper, tin, tantalum and lead are presented. The data were taken with the large acceptance HARP detector in the T9 beam line of the CERN PS. Incident particles were identified by an elaborate system of beam detectors. Thin targets of 5% of a nuclear interaction length were used. The tracking and identification of the produced particles were performed using the forward system of the HARP experiment. Results are obtained for the double-differential cross-sections dσ/dpdΩ mainly at four incident proton beam momenta (3 GeV/c, 5 GeV/c, 8 GeV/c and 12 GeV/c). Measurements are compared with the GEANT4 and MARS Monte Carlo generators. A global parametrization is provided as an approximation of all the collected datasets which can serve as a tool for quick yields estimates.

Absolute momentum calibration of the HARP TPC

In the HARP experiment the large-angle spectrometer is using a cylindrical TPC as main tracking and particle identification detector. The momentum scale of reconstructed tracks in the TPC is the most important systematic error for the majority of kinematic bins used for the HARP measurements of the double-differential production cross-section of charged pions in proton interactions on nuclear targets at large angle. The HARP TPC operated with a number of hardware shortfalls and operational mistakes. Thus it was important to control and characterize its momentum calibration. While it was not possible to enter a direct particle beam into the sensitive volume of the TPC to calibrate the detector, a set of physical processes and detector properties were exploited to achieve a precise calibration of the apparatus. In the following we recall the main issues concerning the momentum measurement in the HARP TPC, and describe the crosschecks made to validate the momentum scale. As a conclusion, this analysis demonstrates that the measurement of momentum is correct within the published precision of 3%.

Forward production of charged pions with incident pi(+/-) on nuclear targets measured at the CERN PS

Measurements of the double-differential π production cross-section in the range of momentum 0.5 GeV/c ≤ p ≤ 8.0 GeV/c and angle 0.025 rad ≤ θ ≤ 0.25 rad in interactions of charged pions on beryllium, carbon, aluminium, copper, tin, tantalum and lead are presented. These data represent the first experimental campaign to systematically measure forward pion hadroproduction. The data were taken with the large acceptance HARP detector in the T9 beam line of the CERN PS. Incident particles, impinging on a 5% nuclear interaction length target, were identified by an elaborate system of beam detectors. The tracking and identification of the produced particles was performed using the forward spectrometer of the HARP detector. Results are obtained for the doubledifferential cross-sections dσ/dpdΩ mainly at four incident pion beam momenta (3 GeV/c, 5 GeV/c, 8 GeV/c and 12 GeV/c). The measurements are compared with the GEANT4 and MARS Monte Carlo simulation.