Charged-pion production in collisions at

J. Adamczewski-Musch; O. Arnold; C. Behnke; A. Belounnas; A. Belyaev; J. C. Berger-Chen; A. Blanco; C. Blume; M. Böhmer; P. Bordalo; S. Chernenko; L. Chlad; I. Ciepał; C. Deveaux; J. Dreyer; E. Epple; L. Fabbietti; O. Fateev; P. Filip; P. Fonte; C. Franco; J. Friese; I. Fröhlich; T. Galatyuk; J. A. Garzón; R. Gernhäuser; S. Gläßel; M. Golubeva; R. Greifenhagen; F. Guber; M. Gumberidze; S. Harabasz; T. Heinz; T. Hennino; S. Hlavac; C. Höhne; R. Holzmann; A. Ierusalimov; A. Ivashkin; B. Kämpfer; T. Karavicheva; B. Kardan; I. Koenig; W. Koenig; M. Kohls; B. W. Kolb; G. Korcyl; G. Kornakov; F. Kornas; R. Kotte; A. Kugler; T. Kunz; A. Kurepin; A. Kurilkin; P. Kurilkin; V. Ladygin; R. Lalik; K. Lapidus; A. Lebedev; L. Lopes; M. Lorenz; T. Mahmoud; L. Maier; A. Malige; A. Mangiarotti; J. Markert; T. Matulewicz; S. Maurus; V. Metag; J. Michel; D. M. Mihaylov; S. Morozov; C. Müntz; R. Münzer; L. Naumann; K. Nowakowski; Y. Parpottas; V. Pechenov; O. Pechenova; O. Petukhov; K. Piasecki; J. Pietraszko; W. Przygoda; K. Pysz; S. Ramos; B. Ramstein; N. Rathod; A. Reshetin; P. Rodriguez-Ramos; P. Rosier; A. Rost; A. Rustamov; A. Sadovsky; P. Salabura; T. Scheib; H. Schuldes; E. Schwab; F. Scozzi; F. Seck; P. Sellheim; I. Selyuzhenkov; J. Siebenson; L. Silva; U. Singh; J. Smyrski; Yu. G. Sobolev; S. Spataro; S. Spies; H. Ströbele; J. Stroth; C. Sturm; O. Svoboda; M. Szala; P. Tlusty; M. Traxler; H. Tsertos; E. Usenko; V. Wagner; C. Wendisch; M. G. Wiebusch; J. Wirth; D. Wójcik; Y. Zanevsky; P. Zumbruch

doi:10.1140/epja/s10050-020-00237-2

2023 Impact factor 2.6

Hadrons and Nuclei

Open Access

Eur. Phys. J. A (2020) 56: 259
https://doi.org/10.1140/epja/s10050-020-00237-2

Regular Article – Experimental Physics

Charged-pion production in $Au + Au$ $\mathbf {Au+Au}$ collisions at $\sqrt{s_{NN}} = 2.4 GeV$ $\sqrt{\mathbf {s}_{\mathbf {NN}}} = 2.4~{\mathbf {GeV}}$

HADES Collaboration, J. Adamczewski-Musch⁵, O. Arnold¹⁰^,11, C. Behnke⁹, A. Belounnas¹⁷, A. Belyaev⁸, J. C. Berger-Chen¹⁰^,11, A. Blanco², C. Blume⁹, M. Böhmer¹¹, P. Bordalo², S. Chernenko⁸, L. Chlad¹⁸, I. Ciepał³, C. Deveaux¹², J. Dreyer⁷, E. Epple¹⁰^,11, L. Fabbietti¹⁰^,11, O. Fateev⁸, P. Filip¹, P. Fonte², C. Franco², J. Friese¹¹, I. Fröhlich⁹, T. Galatyuk⁵^,6, J. A. Garzón¹⁹, R. Gernhäuser¹¹, S. Gläßel⁹, M. Golubeva¹³, R. Greifenhagen⁷, F. Guber¹³, M. Gumberidze⁵^,6, S. Harabasz⁴^,6, T. Heinz⁵, T. Hennino¹⁷, S. Hlavac¹, C. Höhne⁵^,12, R. Holzmann⁵^ar, A. Ierusalimov⁸, A. Ivashkin¹³, B. Kämpfer⁷, T. Karavicheva¹³, B. Kardan⁹, I. Koenig⁵, W. Koenig⁵, M. Kohls⁹, B. W. Kolb⁵, G. Korcyl⁴, G. Kornakov⁶, F. Kornas⁶, R. Kotte⁷, A. Kugler¹⁸, T. Kunz¹¹, A. Kurepin¹³, A. Kurilkin⁸, P. Kurilkin⁸, V. Ladygin⁸, R. Lalik⁴, K. Lapidus¹⁰^,11, A. Lebedev¹⁴, L. Lopes², M. Lorenz⁹, T. Mahmoud¹², L. Maier¹¹, A. Malige⁴, A. Mangiarotti², J. Markert⁵, T. Matulewicz²⁰, S. Maurus¹¹, V. Metag¹², J. Michel⁹, D. M. Mihaylov¹⁰^,11, S. Morozov¹³^,15, C. Müntz⁹, R. Münzer¹⁰^,11, L. Naumann⁷, K. Nowakowski⁴, Y. Parpottas¹⁶, V. Pechenov⁵, O. Pechenova⁵, O. Petukhov¹³, K. Piasecki²⁰, J. Pietraszko⁵, W. Przygoda⁴, K. Pysz³, S. Ramos², B. Ramstein¹⁷, N. Rathod⁴, A. Reshetin¹³, P. Rodriguez-Ramos¹⁸, P. Rosier¹⁷, A. Rost⁶, A. Rustamov⁵, A. Sadovsky¹³, P. Salabura⁴, T. Scheib⁹, H. Schuldes⁹, E. Schwab⁵, F. Scozzi⁶^,17, F. Seck⁶, P. Sellheim⁹, I. Selyuzhenkov⁵^,15, J. Siebenson¹¹, L. Silva², U. Singh⁴, J. Smyrski⁴, Yu. G. Sobolev¹⁸, S. Spataro²¹, S. Spies⁹, H. Ströbele⁹, J. Stroth⁵^,9, C. Sturm⁵, O. Svoboda¹⁸, M. Szala⁹, P. Tlusty¹⁸, M. Traxler⁵, H. Tsertos¹⁶, E. Usenko¹³, V. Wagner¹⁸, C. Wendisch⁵, M. G. Wiebusch⁵, J. Wirth¹⁰^,11, D. Wójcik²⁰, Y. Zanevsky⁸ and P. Zumbruch⁵

¹ Institute of Physics, Slovak Academy of Sciences, 84228, Bratislava, Slovakia
² LIP-Laboratório de Instrumentação e Física Experimental de Partículas, 3004-516, Coimbra, Portugal
³ Institute of Nuclear Physics, Polish Academy of Sciences, 31342, Kraków, Poland
⁴ Smoluchowski Institute of Physics, Jagiellonian University of Cracow, 30-059, Kraków, Poland
⁵ GSI Helmholtzzentrum für Schwerionenforschung GmbH, 64291, Darmstadt, Germany
⁶ Technische Universität Darmstadt, 64289, Darmstadt, Germany
⁷ Institut für Strahlenphysik, Helmholtz-Zentrum Dresden-Rossendorf, 01314, Dresden, Germany
⁸ Joint Institute of Nuclear Research, 141980, Dubna, Russia
⁹ Institut für Kernphysik, Goethe-Universität, 60438, Frankfurt, Germany
¹⁰ Excellence Cluster ‘Origin and Structure of the Universe’, 85748, Garching, Germany
¹¹ Physik Department E62, Technische Universität München, 85748, Garching, Germany
¹² II.Physikalisches Institut, Justus Liebig Universität Giessen, 35392, Giessen, Germany
¹³ Institute for Nuclear Research, Russian Academy of Science, 117312, Moscow, Russia
¹⁴ Institute of Theoretical and Experimental Physics, 117218, Moscow, Russia
¹⁵ National Research Nuclear University MEPhI (Moscow Engineering Physics Institute), 115409, Moscow, Russia
¹⁶ Department of Physics, University of Cyprus, 1678, Nicosia, Cyprus
¹⁷ Laboratoire de Physique des 2 infinis Irene Joliot-Curie, Universite Paris-Saclay, CNRS-IN2P3, 91405, Orsay, France
¹⁸ Nuclear Physics Institute, The Czech Academy of Sciences, 25068, Rez, Czech Republic
¹⁹ LabCAF. F. Física, Universidad de Santiago de Compostela, 15706, Santiago de Compostela, Spain
²⁰ Wydział Fizyki, Instytut Fizyki Doświadczalnej, Uniwersytet Warszawski, 02-093, Warszawa, Poland
²¹ Dipartimento di Fisica and INFN, Università di Torino, 10125, Turin, Italy

^ar hades-info@gsi.de

Received: 25 May 2020
Accepted: 26 August 2020
Published online: 10 October 2020

Abstract

We present high-statistic data on charged-pion emission from Au + Au collisions at $\sqrt{s_{NN}} = 2.4 GeV$ $\sqrt{s_{\mathrm{NN}}} = 2.4~\hbox {GeV}$ (corresponding to $E_{beam} = 1.23 A GeV$ $E_{beam} = 1.23~\hbox {A GeV}$ ) in four centrality classes in the range 0–40% of the most central collisions. The data are analyzed as a function of transverse momentum, transverse mass, rapidity, and polar angle. Pion multiplicity per participating nucleon decreases moderately with increasing centrality. The polar angular distributions are found to be non-isotropic even for the most central event class. Our results on pion multiplicity fit well into the general trend of the available world data, but undershoot by $2.5 σ$ $2.5~\sigma$ data from the FOPI experiment measured at slightly lower beam energy. We compare our data to state-of-the-art transport model calculations (PHSD, IQMD, PHQMD, GiBUU and SMASH) and find substantial differences between the measurement and the results of these calculations.

Copyright comment corrected publication 2020

© The Author(s) 2020. corrected publication 2020

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