ar X iv : h ep - p h / 03 12 22 9 v 3 1 6 Se p 20 04 Spin asymmetries in γN → K ∗ Θ +
نویسندگان
چکیده
Abstract The photoproduction processes of the exotic Θ+(1540) baryon and the K ∗ meson from the nucleon targets, i.e., γn → K∗−Θ+ and γp → K̄∗0Θ+, are investigated in a hadronic model. We consider K and K∗ exchanges as well as the s and u channel nucleon and Θ terms. Various spin asymmetries together with cross sections are first computed in order to study the production mechanisms and the parity of the Θ+(1540) baryon. Within the uncertainties arising from the model-dependence of the production mechanisms and several coupling constants, we find that some target-recoil double spin asymmetries, CTR xx and C TR xz , are sensitive to the parity of Θ +. In addition, the parity asymmetry of this reaction on the neutron target, which can be obtained by analyzing K∗ decay distribution, is found to be useful to estimate the K∗NΘ coupling.
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