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Photoproduction of vector mesons off nucleons near threshold

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 نشر من قبل Bengt Friman
 تاريخ النشر 1996
  مجال البحث
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 تأليف Bengt Friman




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We propose a simple meson-exchange model of the photoproduction of $rho$- and $omega$-mesons off protons near threshold ($E_gamma$ less than 2 GeV). This model provides a good description of the available data and implies a large $rho$-nucleon interaction in the scalar channel ($sigma$-exchange). We use this phenomenological interaction to estimate the leading contribution to the self-energy of $rho$-mesons in matter. The implications of our calculation for experimental studies of the $rho$-meson mass in nuclei are discussed.

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