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arXiv · 0711.4281

Study of dielectron production in C+C collisions at 1 AGeV

HADES Collaboration·G. Agakishiev·C. Agodi·H. Alvarez Pol·A. Balanda·R. Bassini·G. Bellia·D. Belver·A. Belyaev·A. Blanco·M. Boehmer·A. Bortolotti·J. L. Boyard·P. Braun-Munzinger·P. Cabanelas·E. Castro·T. Christ·M. Destefanis·J. Diaz·F. Dohrmann·A. Dybczak·T. Eberl·L. Fabbietti·P. Finocchiaro·P. Fonte·J. Friese·I. Froehlich·T. Galatyuk·J. A. Garzon·R. Gernhaeuser·A. Gil·C. Gilardi·M. Golubeva·D. Gonzalez Diaz·E. Grosse·F. Guber·M. Heilmann·T. Hennino·R. Holzmann·A. Ierusalimov·I. Iori·A. Ivashkin·M. Jurkovic·B. Kaempfer·K. Kanaki·T. Karavicheva·D. Kirschner·I. Koenig·W. Koenig·B. W. Kolb·R. Kotte·A. Kozuch·A. Krasa·F. Krizek·R. Kruecken·W. Kuehn·A. Kugler·A. Kurepin·J. Lamas Valverde·S. Lang·J. S. Lange·K. Lapidus·L. Lopes·L. Maier·A. Mangiarotti·J. Marin·J. Markert·V. Metag·B. Michalska·D. Mishra·E. Moriniere·J. Mousa·M. Muench·C. Muentz·L. Naumann·R. Novotny·J. Otwinowski·Y. C. Pachmayer·M. Palka·Y. Parpottas·V. Pechenov·O. Pechenova·T. Perez·J. Pietraszko·R. Pleskac·W. Przygoda·B. Ramstein·A. Reshetin·M. Roy Stephan·A. Rustamov·A. Sadovsky·B. Sailer·P. Salabura·A. Schmah·R. Simon·Y. Sobolev·S. Spataro·B. Spruck·H. Stroebele·J. Stroth
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Abstract

The emission of e+e- pairs from C+C collisions at an incident energy of 1 GeV per nucleon has been investigated. The measured production probabilities, spanning from the pi0-Dalitz to the rho/omega! invariant-mass region, display a strong excess above the cocktail of standard hadronic sources. The bombarding-energy dependence of this excess is found to scale like pion production, rather than like eta production. The data are in good agreement with results obtained in the former DLS experiment.

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HADES Collaboration, G. Agakishiev, C. Agodi, H. Alvarez Pol, A. Balanda, R. Bassini, G. Bellia, D. Belver, A. Belyaev, A. Blanco, M. Boehmer, A. Bortolotti, J. L. Boyard, P. Braun-Munzinger, P. Cabanelas, E. Castro, T. Christ, M. Destefanis, J. Diaz, F. Dohrmann, A. Dybczak, T. Eberl, L. Fabbietti, P. Finocchiaro, P. Fonte, J. Friese, I. Froehlich, T. Galatyuk, J. A. Garzon, R. Gernhaeuser, A. Gil, C. Gilardi, M. Golubeva, D. Gonzalez Diaz, E. Grosse, F. Guber, M. Heilmann, T. Hennino, R. Holzmann, A. Ierusalimov, I. Iori, A. Ivashkin, M. Jurkovic, B. Kaempfer, K. Kanaki, T. Karavicheva, D. Kirschner, I. Koenig, W. Koenig, B. W. Kolb, R. Kotte, A. Kozuch, A. Krasa, F. Krizek, R. Kruecken, W. Kuehn, A. Kugler, A. Kurepin, J. Lamas Valverde, S. Lang, J. S. Lange, K. Lapidus, L. Lopes, L. Maier, A. Mangiarotti, J. Marin, J. Markert, V. Metag, B. Michalska, D. Mishra, E. Moriniere, J. Mousa, M. Muench, C. Muentz, L. Naumann, R. Novotny, J. Otwinowski, Y. C. Pachmayer, M. Palka, Y. Parpottas, V. Pechenov, O. Pechenova, T. Perez, J. Pietraszko, R. Pleskac, W. Przygoda, B. Ramstein, A. Reshetin, M. Roy Stephan, A. Rustamov, A. Sadovsky, B. Sailer, P. Salabura, A. Schmah, R. Simon, Y. Sobolev, S. Spataro, B. Spruck, H. Stroebele, J. Stroth. 2008-03-21. Study of dielectron production in C+C collisions at 1 AGeV. https://doi.org/10.1016/j.physletb.2008.03.062

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