Measurement of charged pions in 12C + 12C collisions at 1 A GeV and 2 A GeV with HADES

G. Agakishiev; C. Agodi; A. Balanda; G. Bellia; D. Belver; A. Belyaev; J. Bielcik; A. Blanco; A. Bortolotti; J. L. Boyard; P. Braun-Munzinger; P. Cabanelas; S. Chernenko; T. Christ; R. Coniglione; M. Destefanis; J. Díaz; F. Dohrmann; I. Durán; A. Dybczak; T. Eberl; L. Fabbietti; O. Fateev; R. Ferreira-Marques; P. Finocchiaro; P. Fonte; J. Friese; I. Fröhlich; T. Galatyuk; J. A. Garzón; R. Gernhäuser; A. Gil; C. Gilardi; M. Golubeva; D. González-Díaz; E. Grosse; F. Guber; M. Heilmann; T. Heinz; T. Hennino; R. Holzmann; A. Ierusalimov; I. Iori; A. Ivashkin; M. Jurkovic; B. Kämpfer; K. Kanaki; T. Karavicheva; D. Kirschner; I. Koenig; W. Koenig; B. W. Kolb; R. Kotte; A. Kozuch; A. Krása; F. Křížek; R. Krücken; W. Kühn; A. Kugler; A. Kurepin; J. Lamas-Valverde; S. Lang; J. S. Lange; K. Lapidus; L. Lopes; M. Lorenz; L. Maier; C. Maiolino; A. Mangiarotti; J. Marín; J. Markert; V. Metag; B. Michalska; J. Michel; E. Morinière; J. Mousa; M. Münch; C. Müntz; L. Naumann; R. Novotny; J. Otwinowski; Y. C. Pachmayer; M. Palka; Y. Parpottas; V. Pechenov; O. Pechenova; T. Pérez Cavalcanti; P. Piattelli; J. Pietraszko; V. Pospíšil; W. Przygoda; B. Ramstein; A. Reshetin; M. Roy-Stephan; A. Rustamov; A. Sadovsky; B. Sailer; P. Salabura; P. Sapienza; A. Schmah; C. Schroeder; E. Schwab; R. S. Simon; Yu. G. Sobolev; S. Spataro; B. Spruck; H. Ströbele; J. Stroth; C. Sturm; M. Sudol; A. Tarantola; K. Teilab; P. Tlustý; M. Traxler; R. Trebacz; H. Tsertos; V. Wagner; M. Weber; M. Wisniowski; T. Wojcik; J. Wüstenfeld; S. Yurevich; Y. Zanevsky; P. Zhou; P. Zumbruch

doi:10.1140/epja/i2008-10746-7

2021 Impact factor 3.131

Hadrons and Nuclei

Eur. Phys. J. A (2009) 40: 45-59
https://doi.org/10.1140/epja/i2008-10746-7

Regular Article - Experimental Physics

Measurement of charged pions in ¹²C + ¹²C collisions at 1 A GeV and 2 A GeV with HADES

The HADES Collaboration
G. Agakishiev⁸, C. Agodi¹, A. Balanda³^,17, G. Bellia¹^,18, D. Belver¹⁵, A. Belyaev⁶, J. Bielcik⁴, A. Blanco², A. Bortolotti⁹, J. L. Boyard¹³, P. Braun-Munzinger⁴, P. Cabanelas¹⁵, S. Chernenko⁶, T. Christ¹¹, R. Coniglione¹, M. Destefanis⁸, J. Díaz¹⁶, F. Dohrmann⁵, I. Durán¹⁵, A. Dybczak³, T. Eberl¹¹, L. Fabbietti¹¹, O. Fateev⁶, R. Ferreira-Marques²^,19, P. Finocchiaro¹, P. Fonte²^,20, J. Friese¹¹, I. Fröhlich⁷, T. Galatyuk⁴, J. A. Garzón¹⁵, R. Gernhäuser¹¹, A. Gil¹⁶, C. Gilardi⁸, M. Golubeva¹⁰, D. González-Díaz⁴, E. Grosse⁵, F. Guber¹⁰, M. Heilmann⁷, T. Heinz⁴, T. Hennino¹³, R. Holzmann⁴, A. Ierusalimov⁶, I. Iori⁹^,21, A. Ivashkin¹⁰, M. Jurkovic¹¹, B. Kämpfer⁵, K. Kanaki⁵, T. Karavicheva¹⁰, D. Kirschner⁸, I. Koenig⁴, W. Koenig⁴, B. W. Kolb⁴, R. Kotte⁵, A. Kozuch³^,17, A. Krása¹⁴, F. Křížek¹⁴, R. Krücken¹¹, W. Kühn⁸, A. Kugler¹⁴, A. Kurepin¹⁰, J. Lamas-Valverde¹⁵, S. Lang⁴, J. S. Lange⁸, K. Lapidus¹⁰, L. Lopes², M. Lorenz⁷, L. Maier¹¹, C. Maiolino¹, A. Mangiarotti², J. Marín¹⁵, J. Markert⁷, V. Metag⁸, B. Michalska⁹, J. Michel⁷, E. Morinière¹³, J. Mousa¹²^*, M. Münch⁴, C. Müntz⁷, L. Naumann⁵, R. Novotny⁸, J. Otwinowski³, Y. C. Pachmayer⁷, M. Palka⁴, Y. Parpottas¹², V. Pechenov⁸, O. Pechenova⁸, T. Pérez Cavalcanti⁸, P. Piattelli¹, J. Pietraszko⁴, V. Pospíšil¹⁴, W. Przygoda³^,17, B. Ramstein¹³, A. Reshetin¹⁰, M. Roy-Stephan¹³, A. Rustamov⁴, A. Sadovsky¹⁰, B. Sailer¹¹, P. Salabura³, P. Sapienza¹, A. Schmah¹¹, C. Schroeder⁴, E. Schwab⁴, R. S. Simon⁴, Yu. G. Sobolev¹⁴, S. Spataro⁸, B. Spruck⁸, H. Ströbele⁷, J. Stroth⁷^,4, C. Sturm⁷, M. Sudol¹³, A. Tarantola⁷, K. Teilab⁷, P. Tlustý¹⁴, M. Traxler⁴, R. Trebacz³, H. Tsertos¹², V. Wagner¹⁴, M. Weber¹¹, M. Wisniowski³, T. Wojcik³, J. Wüstenfeld⁵, S. Yurevich⁴, Y. Zanevsky⁶, P. Zhou⁵ and P. Zumbruch⁴

¹ Istituto Nazionale di Fisica Nucleare, Laboratori Nazionali del Sud, 95125, Catania, Italy
² LIP-Laboratório de Instrumentação e Física Experimental de Partículas, 3004-516, Coimbra, Portugal
³ Smoluchowski Institute of Physics, Jagiellonian University of Cracow, 30-059, Kraków, Poland
⁴ GSI Helmholtzzentrum für Schwerionenforschung, 64291, Darmstadt, Germany
⁵ Institut für Strahlenphysik, Forschungszentrum Dresden-Rossendorf, 01314, Dresden, Germany
⁶ Joint Institute of Nuclear Research, 141980, Dubna, Russia
⁷ Institut für Kernphysik, Johann Wolfgang Goethe-Universität, 60438, Frankfurt, Germany
⁸ II. Physikalisches Institut, Justus Liebig Universität Giessen, 35392, Giessen, Germany
⁹ Istituto Nazionale di Fisica Nucleare, Sezione di Milano, 20133, Milano, Italy
¹⁰ Institute for Nuclear Research, Russian Academy of Science, 117312, Moscow, Russia
¹¹ Physik Department E12, Technische Universität München, 85748, München, Germany
¹² Department of Physics, University of Cyprus, 1678, Nicosia, Cyprus
¹³ Institut de Physique Nucléaire, CNRS/IN2P3 - Université Paris Sud, F-91406, Orsay Cedex, France
¹⁴ Nuclear Physics Institute, Academy of Sciences of Czech Republic, 25068, Rez, Czech Republic
¹⁵ Departamento de Física de Partículas, University of Santiago de Compostela, 15782, Santiago de Compostela, Spain
¹⁶ Instituto de Física Corpuscular, Universidad de Valencia-CSIC, 46971, Valencia, Spain
¹⁷ Panstwowa Wyzsza Szkola Zawodowa, 33-300, Nowy Sacz, Poland
¹⁸ Dipartimento di Fisica e Astronomia, Università di Catania, 9125, Catania, Italy
¹⁹ Universidade de Coimbra, Coimbra, Portugal
²⁰ ISEC Coimbra, Coimbra, Portugal
²¹ Dipartimento di Fisica, Università di Milano, 20133, Milano, Italy

^* e-mail: mousa@ucy.ac.cy

Received: 11 August 2008
Revised: 23 January 2009
Accepted: 4 March 2009
Published online: 4 April 2009

Abstract

We present the results of a study of charged-pion production in ¹²C + ¹²C collisions at incident beam energies of 1A GeV and 2A GeV using the HADES spectrometer at GSI. The main emphasis of the HADES program is on the dielectron signal from the early phase of the collision. Here, however, we discuss the data with respect to the emission of charged hadrons, specifically the production of mesons, which are related to neutral pions representing a dominant contribution to the dielectron yield. We have performed the first large-angular-range measurement of the distribution of mesons for the ¹²C + ¹²C collision system covering a fairly large rapidity interval. The pion yields, transverse-mass and angular distributions are compared with calculations done within a transport model, as well as with existing data from other experiments. The anisotropy of pion production is systematically analyzed.