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Dielectron Cross Section Measurements in Nucleus-Nucleus Reactions at 1.0 A GeV

R. J. Porter·S. Beedoe·R. Bossingham·M. Bougteb·W. B. Christie·J. Carroll·W. G. Gong·T. Hallman·L. Heilbronn·H. Z. Huang·G. Igo·P. Kirk·G. Krebs·A. Letessier-Selvon·L. Madansky·F. Manso·H. S. Matis·J. Miller·C. Naudet·M. Prunet·G. Roche·L. S. Schroeder·P. Seidl·Z. F. Wang·R. C. Welsh·W. K. Wilson·A. Yegneswaran
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Abstract

We present measured dielectron production cross sections for Ca+Ca, C+C, He+Ca, and d+Ca reactions at 1.0 A GeV. Statistical uncertainties and systematic effects are smaller than in previous DLS nucleus-nucleus data. For pair mass < 0.35 GeV/c2 : 1) the Ca+Ca cross section is larger than the previous DLS measurement and current model results, 2) the mass spectra suggest large contributions from pi0 and eta Dalitz decays, and 3) dsigma/dM is proportional to ApAt. For M > 0.5 GeV/c2 the Ca+Ca to C+C cross section ratio is significantly larger than the ratio of ApAt values.

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R. J. Porter, S. Beedoe, R. Bossingham, M. Bougteb, W. B. Christie, J. Carroll, W. G. Gong, T. Hallman, L. Heilbronn, H. Z. Huang, G. Igo, P. Kirk, G. Krebs, A. Letessier-Selvon, L. Madansky, F. Manso, H. S. Matis, J. Miller, C. Naudet, M. Prunet, G. Roche, L. S. Schroeder, P. Seidl, Z. F. Wang, R. C. Welsh, W. K. Wilson, A. Yegneswaran. 1997-03-04. Dielectron Cross Section Measurements in Nucleus-Nucleus Reactions at 1.0 A GeV. https://doi.org/10.1103/physrevlett.79.1229

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