Understanding Transversity: Present and Future
نویسنده
چکیده
The transverse polarization, or transversity, distribution of quarks h1(x) – also called ∆T q(x) – has been the subject of an intense theoretical work in the last decade (for reviews, see Refs. 1 and 2), and the corresponding observables are now actively investigated in many experiments. Let us start by recalling the partonic definition of h1(x). Given a transversely polarized hadron, if we denote by q↑(q↓) the number density of quarks with polarization parallel (antiparallel) to that of the hadron, the transversity distribution is the difference h1(x) = q↑(x) − q↓(x). In field-theoretical terms, h1(x) is given by (P and S are the momentum and the spin of the hadron, respectively)
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تاریخ انتشار 2005