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In the present paper we discuss the P-wave bottomonium production within both color octet and color singlet models in next-to-leading order at LHC energies. We calculate the cross section and the transverse momentum distributions for the 1;2b states. We obtain that the ratios of bottomonium and charmonium spin state production are fundamentally complementary at different p T scales. We give predictions for the ratio of the n ¼ 2 and n ¼ 1 radial excitations production cross sections.

In the present work we study production of J/ψ+χ c and J/ψ+J/ψ in LHC. The first process is forbidden at the leading order in gluon fusion due to the C-parity conservation, and the first non-vanishing contribution is given by the process with additional emission of real gluon. Considering the direct production of J/ψ + J/ψ, where the leading order is allowed, we have found that the contribution from the higher order process with real gluon emission is comparable and even more significant than the leading order. Moreover, account of this higher order effect dramatically changes kinematical distributions. Through the present paper we study in details different channels of paired J/ψ + J/ψ production: direct J/ψ + J/ψ production, feed-down from J/ψ + χ c channel, double parton scattering. We also try to find kinematical distributions that are most suitable to separate these different channels.

The paper is devoted to theoretical consideration of inclusive η c,b meson production at LHC. It is shown that existing experimental data on η c meson production at LHCb detector can be described in the framework of NRQCD formalism and colorsinglet component with phenomenological value of matrix element |R(0)| 2 gives main contribution. Using this model we present theoretical prediction for integrated cross sections and transverse momentum distributions for inclusive η c production at other LHC detectors. The case of η b meson production at LHC is also considered.

Inclusive production of ΥJ/ψ pair in proton-proton interation at LHCb is considered. This process is forbidden at leading order of perturbation theory, so such channels as double parton scattering, χ b χ c pair production with subsequent radiative decays of P -wave quarkonia, contributions of color-octet states, and NLO corrections are studied in details. For all these channels we present theoretical predictions of total cross sections at LHCb and distributions over different kinematical variables.According to presented in the paper results, double parton interaction gives main contribution to the cross section of the considered reaction. PACS numbers: 13.85.-t, 14.40.Pq, 12.39.Jh I. INTRODUCTION Inclusive double production of heavy quarkonia was observed in NA3 experiment, where production of two J/ψ mesons in πN interaction was studied. The cross section of double J/ψ production was suppressed by about three orders of magnitude in comparison with single J/ψ. Such suppression can be easily explained at leading order (LO) of perturbative QCD [1, 2]. In low energy hadronic collisions quark-antiquark subprocess qq → J/ψJ/ψ gives main contribution to the considered reaction, while in the case of high energy interactions gluonic subprocesses gg → J/ψJ/ψ are dominant. Leading order O(α 4 s ) QCD predictions and subsequent next to leading order (NLO) corrections [3] are in good agreement with * Electronic address: Anatolii.Likhoded@ihep.ru † Electronic address: alexey.luchinsky@ihep.ru ‡ Electronic address: stvlpos@mail.ru

We present theoretical analysis of paired B c mesons production in e + e − annihilation at different energy scales taking into account full next-to-leading order QCD corrections. Both possible electroweak channels are considered: production via virtual photon and via virtual Z-boson. We study in detail the role of radiative QCD corrections, which were found to be significant especially at low energies. It is shown that the contribution from Z-boson is significant at high energies ( √ s > M Z /2) especially in the case of paired production of pseudo-scalar and vector (B c + B * c ) mesons. Azimuthal asymmetry induced by a P-violating weak interaction with Z-boson is also analyzed. Email addresses: Alexander.Berezhnoy@cern.ch (A.V. Berezhnoy), Anatolii.Likhoded@ihep.ru (A.K. Likhoded), onish@bk.ru (A.I. Onishchenko), stvlpos@mail.ru (S.V. Poslavsky) NRQCD factorization and projectorsProduction and bound state dynamics of quarkonia involves several different energy scales. First, we have hard scales given by heavy quark masses m b and m c . Next, there are so called soft and ultrasoft scales. The soft scale is given by the relative momentum of heavy quark-antiquark pair in the quarkonium rest frame |p| ∼ mv (∼ 1/r). Here v is the relative velocity of quarkantiquark motion, r is the radius of quarkonium and m is the reduced mass, which in the case of B c meson is given by m = m c m b m c +m b . The ultrasoft scale is given by kinetic energy of quarkantiquark motion inside quarkonium E ∼ mv 2 and of course we have nonperturbative confinement scale Λ QCD . The nonrelativistic QCD (NRQCD) is the effective theory obtained by integrating out hard degrees of freedom from QCQ. The general hierarchy of scales for quarkonia production and bound state dynamics is m b , m c mv, mv 2 , Λ QCD , as v 1. First, it sets a firm ground