%0 Journal Article
%T Origin of the low-mass electron pair excess in light nucleus-nucleus collisions
%A HADES Collaboration (Agakishiev, G. et al
%A Diaz, J.
%A Gil, A.
%J Physics Letters B
%D 2010
%V 690
%N 2
%I Elsevier Science Bv
%@ 0370-2693
%G English
%F HADESCollaborationAgakishiev_etal2010
%O ISI:000279513800003
%O exported from refbase (https://references.ific.uv.es/refbase/show.php?record=413), last updated on Fri, 20 May 2016 14:29:30 +0000
%X We report measurements of electron pair production in elementary p + p and d + p reactions at 1.25 GeV/mu with the HADES spectrometer. For the first time, the electron pairs were reconstructed for n + p reactions by detecting the proton spectator from the deuteron breakup. We find that the yield of electron pairs with invariant mass Me+e- > 0.15 GeV/c(2) is about an order of magnitude larger in n + p reactions as compared to p + p. A comparison to model calculations demonstrates that the production mechanism is not sufficiently described yet. The electron pair spectra measured in C + C reactions are compatible with a superposition of elementary n + p and p + p collisions, leaving little room for additional electron pair sources in such light collision systems.
%K Virtual bremsstrahlung
%K Dileptons
%K Nucleon-nucleon collisions
%R 10.1016/j.physletb.2010.05.010
%U http://arxiv.org/abs/0910.5875
%U https://doi.org/10.1016/j.physletb.2010.05.010
%P 118-122