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Dielectron production in pp and dp collisions at 1.25 GeV/u with HADES

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 نشر من قبل Kirill Lapidus
 تاريخ النشر 2009
  مجال البحث
والبحث باللغة English
 تأليف K. Lapidus




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Inclusive production of e+e--pairs in pp and dp collisions at a kinetic beam energy of 1.25 GeV/u has been studied with the HADES spectrometer. In the latter case, the main goal was to obtain data on pair emission in quasi-free np collisions. To select this particular reaction channel the HADES experimental setup was extended with a Forward Wall hodoscope, which allowed to register spectator protons. Here, the measured invariant mass distributions demonstrate a strong enhancement of the pair yield for M > 140 MeV/c2 in comparison to pp data.



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