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Tyree-body mechanisms in the 3^He(e,ep) reactions at high missing momentum

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 نشر من قبل Jean-Marc Laget
 تاريخ النشر 2004
  مجال البحث
والبحث باللغة English
 تأليف J. M. Laget




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A particular three-body mechanism is responsible for the missing strength which has been reported in $^3$He(e,e$$p) reactions at missing momentum above 700 MeV/c. It corresponds to the absorption of the virtual photon by a nucleon at rest which subsequently propagates on-shell and emits a meson which is reabsorbed by the pair formed by the two other nucleons. Its amplitude, which is negligible in photon induced reactions as well as in the electro-production of an on-shell meson, becomes maximal in the quasi-free kinematics (X=1). It relates the amplitude of the $^3$He(e,e$$p)D reaction to the amplitude of $pD$ elastic scattering at backward angles.



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