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Anti-hyperon Polarization in $pA$ and $Sigma^-A$ Collisions and Intrinsic Antidiquark State in Incident Baryon

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 نشر من قبل Shin-Ichi Nakariki
 تاريخ النشر 2011
  مجال البحث
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We discuss the relation between the polarization of inclusively produced (anti)-hyperons and the incident baryon states in the framework of the constituent quark-diquark cascade model. We assume that there is an intrinsic diquark-antidiquark state in the incident baryon, in which the intrinsic diquark immediately fragments into a non-leading baryon and the antidiquark behaves as a valence constituent. It is also assumed that the valence (anti)diquark in the incident nucleon tends to combine selectively with a spin-down sea quark and, on the othe hand, the spin-up valence quark in the projectile is chosen by a sea (anti)diquadk in preference to the spin-down valence quark. It is found that the incident spin-1/2 baryon is mainly composed of a spin-0 valence diquark and a valence quark, and contains an intrinsic diquark-antidiquark state with a probability of about 7%.

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