We discuss the mass splittings for the S-wave triply heavy pentaquark states with the Q Q Qqq (Q = b, c; q = u, d, s) configuration which is a mirror structure of QQqqq. The latter configuration is related with the nature of P c (4380) observed by the LHCb Collaboration. The considered pentaquark masses are estimated with a simple method. One finds that such states are probably not narrow even if they do exist. This leaves room for molecule interpretation for a state around the low-lying threshold of a doubly heavy baryon and a heavy-light meson, e.g. cc D, if it were observed. As a by product, we conjecture that upper limits for the masses of the conventional triply heavy baryons can be determined by the masses of the conventional doubly heavy baryons. * c 2518.4

We compute, for $t \bar t$ production at the LHC and at the Tevatron, several charge asymmetries to NLO QCD, including also the electromagnetic and weak-interaction corrections. We calculate these asymmetries both inclusively and with additional kinematic cuts and compare our results, where possible, with recent experimental results and with SM predictions. The $t \bar t$ asymmetries induce also corresponding asymmetries for the charged leptons from semileptonic top-quark decay. Although these asymmetries are, in the SM, smaller than the corresponding ones for top quarks, they are expected to be measurable quite precisely. In fact, measurement of a lepton asymmetry in $\ell$ + jets events was reported by the D$\emptyset$ and CDF experiments. We analyze and compute to NLO in the gauge couplings leptonic charge asymmetries for dileptonic and semileptonic $\ttbar$ events, with and without acceptance cuts, at the Tevatron and the LHC.Comment: Some references and a note added on comparisons with recent experimental results. Published in Phys. Rev. D 86, 034026 (2012

In ongoing and upcoming hadron collider experiments, top quark physics will play an important rôle in testing the Standard Model and its possible extensions. In this work we present analytic results for the differential cross sections of top quark pair production in hadronic collisions at next-to-leading order in the QCD coupling, keeping the full dependence on the spins of the top quarks. These results are combined with the corresponding next-to-leading order results for the decay of polarized top quarks into dilepton, lepton plus jets, and all jets final states. As an application we predict double differential angular distributions which are due to the QCD-induced top quark spin correlations in the intermediate state. In addition to the analytic results, we give numerical results in terms of fit functions that can easily be used in an experimental analysis.

We investigate a number of observables that are and will be instrumental in the exploration of tt production and decay at the Tevatron and the LHC. For this analysis we made a computer program that incorporates besides the NLO QCD corrections to tt production and decay also mixed weak-QCD corrections to the production amplitudes, and that allows for studies of correlated versus uncorrelated tt events. In this paper we analyze and compute observables mostly for dileptonic tt final states to next-toleading order in the strong and weak gauge couplings (NLOW), with selection cuts. We calculate charge asymmetries of the top quark and of ℓ = e, µ and we compare, where possible, with experimental results. We show that top-quark spin correlations affect a leptonic pair asymmetry (which has not been measured so far) by ∼ 7%. We determine several dileptonic angular correlations, which reflect tt spin correlations, namely the beam, off-diagonal and helicity correlation, and the opening angle distribution (defined in the t,t rest frames) when selection cuts are applied. Our NLOW predictions for the beam, off-diagonal, and helicity correlation for the Tevatron agree with recent measurements by the CDF and D0 experiments. In addition we make predictions for estimators of these correlations as functions of M tt . These estimators may prove useful for the Tevatron and also in the early rounds of LHC data-analyses, where the event numbers will not be abundant. Furthermore, we compute to NLOW in the gauge couplings two dilepton angular correlations that are defined in the laboratory frame, for correlated and uncorrelated tt events at the LHC. Finally, based on our SM results, we identify several observables that allow to search for non-standard parity-and CP-violating interactions, especially with future LHC data.