Exploring time like tranistions in pp, πp and AA reactions with HADES

Piotr Salabura; J. Adamczewski-Musch; B. Arnoldi-Meadows; A. Belounnas; A. Belyaev; A. Blanco; C. Blume; M. Böhmer; S Borisenko; L. Chlad; P Chudoba; I. Ciepał; D. Dittert; J. Dreyer; W. Esmail; M. Dürr; L. Fabbietti; S. Fateev; P. Fonte; J. Friese; I. Fröhlich; J. Förtsch; T. Galatyuk; R. Gernhäuser; O. Golosov; M. Golubeva; R. Greifenhagen; F. Guber; M. Gumberidze; S. Harabasz; R. Hensch; C. Höhne; R. Holzmann; H. Huck; A. Ierusalimov; A. Ivashkin; B. Kämpfer; K-H. Kampert; B. Kardan; I. Koenig; W. Koenig; G. Kornakov; F. Kornas; R. Kotte; A. Kozela; I. Kres; J. Kuboś; A. Kugler; P. Kulesa; V. Ladygin; R. Lalik; A. Lebedev; S. Lebedev; S. Linev; L. Lopes; M. Lorenz; G. Lykasov; T. Mahmoud; A. Malige; J. Markert; T. Matulewicz; S. Maurus; V. Metag; J. Michel; S. Morozov; C. Müntz; L. Naumann; K. Nowakowski; J.-H. Otto; V. Patel; C. Pauly; V. Pechenov; O. Pechenova; O. Petukhov; D. Pfeifer; K. Piasecki; J. Pietraszko; A. Prozorov; W. Przygoda; K. Pysz; B. Ramstein; N. Rathod; A. Reshetin; L. Ritman; P. Rodriguez-Ramos; A. Rost; P. Salabura; F. Scozzi; F. Seck; I. Selyuzhenkov; I. Shabanov; US Singh; J. Smyrski; S. Spies; H. Ströbele; J. Stroth; J. Stumm; O. Svoboda; M. Szala; P. Tlusty; M. Traxler; C. Ungethüm; O. Vazquez-Doce; V. Wagner; A.A. Weber; C. Wendisch; M.G. Wiebusch; P. Wintz; J. Wirth; A. Zhilin; P. Zumbruch

doi:10.1051/epjconf/202024101013

Proceedings

Open Access

EPJ Web of Conferences 241, 01013 (2020)
https://doi.org/10.1051/epjconf/202024101013

Exploring time like tranistions in pp, πp and AA reactions with HADES

Piotr Salabura³^*, J. Adamczewski-Musch⁴, B. Arnoldi-Meadows⁸, A. Belounnas¹⁶, A. Belyaev⁷, A. Blanco¹, C. Blume⁸, M. Böhmer¹⁰, S Borisenko¹³, L. Chlad¹⁷, P Chudoba¹⁷, I. Ciepał², D. Dittert⁵, J. Dreyer⁶, W. Esmail¹², M. Dürr¹¹, L. Fabbietti¹⁰^,9, S. Fateev⁷, P. Fonte¹^,a, J. Friese¹⁰, I. Fröhlich⁸, J. Förtsch¹⁹, T. Galatyuk⁵^,4, R. Gernhäuser¹⁰, O. Golosov¹⁵, M. Golubeva¹³, R. Greifenhagen⁶^,b, F. Guber¹³, M. Gumberidze⁴, S. Harabasz⁵^,3, R. Hensch⁸, C. Höhne¹¹^,4, R. Holzmann⁴, H. Huck⁸, A. Ierusalimov⁷, A. Ivashkin¹³, B. Kämpfer⁶^,b, K-H. Kampert¹⁹, B. Kardan⁸, I. Koenig⁴, W. Koenig⁴, G. Kornakov⁵, F. Kornas⁵, R. Kotte⁶, A. Kozela², I. Kres¹⁹, J. Kuboś², A. Kugler¹⁷, P. Kulesa¹², V. Ladygin⁷, R. Lalik³, A. Lebedev¹⁴, S. Lebedev¹¹^,7, S. Linev⁴, L. Lopes¹, M. Lorenz⁸, G. Lykasov⁷, T. Mahmoud¹¹, A. Malige³, J. Markert⁴, T. Matulewicz¹⁸, S. Maurus¹⁰, V. Metag¹¹, J. Michel⁸, S. Morozov¹³^,15, C. Müntz⁸, L. Naumann⁶, K. Nowakowski³, J.-H. Otto¹¹, V. Patel¹⁹, C. Pauly¹⁹, V. Pechenov⁴, O. Pechenova⁴, O. Petukhov¹³, D. Pfeifer¹⁹, K. Piasecki¹⁸, J. Pietraszko⁴, A. Prozorov¹⁷, W. Przygoda³, K. Pysz², B. Ramstein¹⁶, N. Rathod³, A. Reshetin¹³, L. Ritman¹², P. Rodriguez-Ramos¹⁷, A. Rost⁵, P. Salabura³, F. Scozzi⁵^,16, F. Seck⁵, I. Selyuzhenkov⁴^,15, I. Shabanov¹³, US Singh³, J. Smyrski³, S. Spies⁸, H. Ströbele⁸, J. Stroth⁸^,4, J. Stumm⁸, O. Svoboda¹⁷, M. Szala⁸, P. Tlusty¹⁷, M. Traxler⁴, C. Ungethüm⁵, O. Vazquez-Doce¹⁰^,9, V. Wagner¹⁷, A.A. Weber¹¹, C. Wendisch⁴, M.G. Wiebusch⁸, P. Wintz¹², J. Wirth¹⁰^,9, A. Zhilin¹⁴ and P. Zumbruch⁴

¹ LIP-Laboratório de Instrumentação e Física Experimental de Partículas , 3004-516 Coimbra, Portugal
² Institute of Nuclear Physics, Polish Academy of Sciences, , 31342 Kraków, Poland
³ Smoluchowski Institute of Physics, Jagiellonian University of Cracow, 30-059 Kraków, Poland
⁴ GSI Helmholtzzentrum für Schwerionenforschung GmbH, 64291 Darmstadt, Germany
⁵ Technische Universität Darmstadt, 64289 Darmstadt, Germany
⁶ Institut für Strahlenphysik, Helmholtz-Zentrum Dresden-Rossendorf, 01314 Dresden, Germany
⁷ Joint Institute of Nuclear Research, 141980 Dubna, Russia
⁸ Institut für Kernphysik, Goethe-Universität, 60438 Frankfurt, Germany
⁹ Excellence Cluster ’Origin and Structure of the Universe’, 85748 Garching, Germany
¹⁰ Physik Department E62, Technische Universität München, 85748 Garching, Germany
¹¹ II.Physikalisches Institut, Justus Liebig Universität Giessen, 35392 Giessen, Germany
¹² Forschungszentrum Juelich, 52428 Juelich, 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 Institut de Physique Nucléaire, CNRS-IN2P3, Univ. Paris-Sud, Université Paris-Saclay, F-91406 Orsay Cedex, France
¹⁷ Nuclear Physics Institute, The Czech Academy of Sciences, 25068 Rez Czech Republic
¹⁸ Uniwersytet Warszawski - Instytut Fizyki Do´swiadczalnej, 02-093 Warszawa, Poland
¹⁹ Bergische Universität Wuppertal, 42119 Wuppertal, Germany
^a also at Coimbra Polytechnic - ISEC, Coimbra, Portugal
^b also at Technische Universität Dresden, 01062 Dresden, Germany

^* Corresponding author:

Published online: 22 September 2020

Abstract

Radiative transition of an excited baryon to a nucleon with emission of a virtual massive photon converting to dielectron pair (Dalitz decays) provides important information about baryon-photon coupling at low q² in timelike region. A prominent enhancement in the respective electromagnetic transition Form Factors (etFF) at q² near vector mesons ρ/ω poles has been predicted by various calculations reflecting strong baryon-vector meson couplings. The understanding of these couplings is also of primary importance for the interpretation of the emissivity of QCD matter studied in heavy ion collisions via dilepton emission. Dedicated measurements of baryon Dalitz decays in proton-proton and pion-proton scattering with HADES detector at GSI/FAIR are presented and discussed. The relevance of these studies for the interpretation of results obtained from heavy ion reactions is elucidated on the example of the HADES results.

© The Authors, published by EDP Sciences, 2020

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