50,796 research outputs found

    Double longitudinal-spin asymmetries in J/ψJ/\psi production at RHIC

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    The double longitudinal-spin asymmetry, ALLA_{LL}, of the J/ψJ/\psi production in polarized proton-proton collisions is presented in this paper at QCD next-to-leading order. It is found that the obtained values of ALLA_{LL} are in general consistent with the PHENIX measurements. Various sets of the long-distance matrix elements (LDMEs) are employed in our calculation to study the possible theoretical uncertainties. It is found that, for p_t<5\gev, all these LDMEs lead to almost the same results, which are within the tolerance of the experimental data uncertainties

    Derivative Formula and Applications for Degenerate Diffusion Semigroups

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    By using the Malliavin calculus and solving a control problem, Bismut type derivative formulae are established for a class of degenerate diffusion semigroups with non-linear drifts. As applications, explicit gradient estimates and Harnack inequalities are derived.Comment: 18 page
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