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In this study, the form factors of B (s) to light D-wave tensor mesons with J PC = 2 - - ( ρ 2 , ω 2 , K 2 and ϕ 2 ) are calculated via the light cone sum rules (LCSR) in the framework of heavy quark effective eld theory (HQEFT). Firstly, the expressions of form factors in terms of the light cone distribution amplitudes (LCDAs) of tensor mesons are derived via the LCSR at the leading order of heavy quark expansion. Similar to the case of 2 + + tensor mesons, the penguin type form factors can be obtained directly from the corresponding semileptonic ones. Considering the light tensor meson LCDAs to twist-3 and quark mass corrections, we give the numerical results of form factors systematically. Based on the form factors given here, we investigate the branching ratios, longitudinal polarization fractions and forward-backward asymmetries of relevant charged current induced semileptonic decays. Our results may be tested by more precise experiments in the future. [ABSTRACT FROM AUTHOR]

In this paper, the form factors of D(s) to light tensor mesons a2(1320), K 2 ∗ (1 4 3 0) , f 2 (1 2 7 0) , f 2 ′ (1 5 2 5) and corresponding semileptonic decays are investigated through the method of light cone sum rules (LCSR) in the framework of heavy quark effective field theory (HQEFT). Considering the light cone distribution amplitudes (DAs) of tensor mesons to twist-3, we give numerical results of form factors systematically, which are necessary inputs for the analysis of relevant D(s) decays. Based on the form factor results, the relevant semileptonic decays induced by charged current (CC) as well as flavor changing neutral current (FCNC) are studied. Our predictions for the branching ratios, longitudinal polarization fractions and forward–backward asymmetries can be tested by more precise experiments such as LHCb, BESIII and BelleII in the future. [ABSTRACT FROM AUTHOR]

We consider the quantum quench dynamics of a Heisenbergâ€"Ising spin ladder which is an archetypal model in which confinement of elementary excitations is triggered by internal interactions rather than an external field. We show that the confinement strongly affects the light cone structure of correlation functions providing signatures of the velocities of the mesons of the model. We also show that the meson masses can be measured from the real time analysis of the evolution of the order parameter. [ABSTRACT FROM AUTHOR]

Heavy mesons and doubly heavy baryons with the dynamic properties governed by the light quark motion relative to the fixed center of forces are studied within the Heavy Quark Effective Theory. The distribution amplitudes of the hadrons in question are compared, model functions of these amplitudes for the doubly heavy baryons are introduced, and their scale dependence is investigated. [ABSTRACT FROM AUTHOR]

Recently, LHCb Collaboration announced the discovery of radial excitations of D s and B s mesons. In present work, we calculate the most promising strong and electromagnetic decay widths of radially excited D s (2 S) and B s (2 S) mesons within the light cone QCD sum rules method. [ABSTRACT FROM AUTHOR]

In collinear factorization, light-cone distribution amplitudes (LCDAs) are key ingredients to calculate the production rate of a hadron in high energy exclusive processes. For a doubly-heavy meson system (such as B , J/ ψ, Y etc), the LCDAs contain perturbative scales that can be integrated out and then are re-factorized into products of perturbatively calculable distribution parts and non-relativistic QCD matrix elements. In this re-factorization scheme, the LCDAs are known at next-to-leading order in the strong coupling constant α and at leading order in the velocity expansion. In this work, we calculate the $$ \mathcal{O}\left({v}^2\right) $$ corrections to twist-2 LCDAs of S-wave B mesons. These results are applicable to heavy quarkonia like η , J/ ψ and Y by setting m = m . We apply these relativistically corrected LCDAs to study their inverse moments and a few Gegenbauer moments which are important for phenomenological study. We point out that the relativistic corrections are sizable, and comparable with the next-to-leading order radiative corrections. These results for LCDAs are useful in future theoretical analyses of the productions of heavy quarkonia and B mesons. [ABSTRACT FROM AUTHOR]

B c mesons are laboratories for probing heavy quark physics. Furthermore, they decay into charmonia and hence their decays can be used to analyze possible exotic charmonium. In this work, the semileptonic decays of B c mesons into P wave charmonia are analysed using light cone QCD sum rules (LCSR). The distributions amplitudes for the charmonia are taken from a quark model computation. The obtained decay rates for the ground state and excited charmonia are compared with the results found in the literature. [ABSTRACT FROM AUTHOR]

We present the results of a lattice study of the normalization constants and second moments of the light-cone distribution amplitudes of longitudinally and transversely polarized ρ mesons. The calculation is performed using two flavors of dynamical clover fermions at lattice spacings between 0.060 fm and 0.081 fm, different lattice volumes up to m L = 6.7 and pion masses down to m = 150 MeV. Bare lattice results are renormalized non-perturbatively using a variant of the RI′-MOM scheme and converted to the $$ \overline{\mathrm{MS}} $$ scheme. The necessary conversion coefficients, which are not available in the literature, are calculated. The chiral extrapolation for the relevant decay constants is worked out in detail. We obtain for the ratio of the tensor and vector coupling constants f / f = 0.629(8) and the values of the second Gegenbauer moments a = 0.132(27) and a = 0.101(22) at the scale μ = 2 GeV for the longitudinally and transversely polarized ρ mesons, respectively. The errors include the statistical uncertainty and estimates of the systematics arising from renormalization. Discretization errors cannot be estimated reliably and are not included. In this calculation the possibility of ρ → ππ decay at the smaller pion masses is not taken into account. [ABSTRACT FROM AUTHOR]

The strong coupling constants of the π and K mesons with negative parity octet baryons are estimated within the light cone QCD sum rules. It is observed that all strong coupling constants, similarly to the case for the positive parity baryons, can be described in terms of three invariant functions, where two of them correspond to the well known F and D couplings in the S U ( 3 ) f symmetry, and the third function describes the S U ( 3 ) f symmetry violating effects. We compare our predictions on the strong coupling constants of pseudoscalar mesons of negative parity baryons with those corresponding to the strong coupling constants for the positive parity baryons. [ABSTRACT FROM AUTHOR]

We report some applications of QCD light cone sum rules (LCSR) to $$B$$ meson weak decays. Special emphasis is on estimates of the form factors for $$B$$ decays into a pseudoscalar ( $$P$$ )/vector ( $$V$$ ) meson, with a certain chiral current correlator. The main new ingredient, as compared with the case of the standard correlators, is that in the operator product expansion calculations, the contributions due to the twist-3 distribution amplitudes of the related light mesons, which are less known and would bring a larger uncertainty to the calculations with the standard correlators, cancel out fully in the $$B\rightarrow P$$ case and do out partially in the $$B\rightarrow V$$ one. An important observation, which is similar to that in soft collinear effective theory, is made in twist-3 approximation: whereas only one independent form factor is needed for parameterizing the hadronic matrix elements for a $$B\rightarrow P$$ transition induced by all the relevant heavy-light quark currents, there exist two independent form factors under the condition of neglecting the terms suppressed by a factor of $$m_V^2$$ , for the $$B\rightarrow V$$ transition. Therefore, the improved LCSR approach could be of stronger predictive power for the weak form factors. Also, this approach is employed to understand the $$B\rightarrow D$$ transitions by introducing a leading twist-2 DA for an energetic $$D$$ meson, combined with some of other QCD-based approaches. A detailed QCD next-to-leading order calculation of the $$B\rightarrow \pi $$ form factors is presented for an illustrative purpose, and the sum rule results are used to extract the Cabibbo-Kobayashi-Maskawa matrix element $$|V_{ub}|$$ from the latest BaBar data. [ABSTRACT FROM AUTHOR]

Abstract: We study the form factors for a heavy meson into the S-wave system with an invariant mass below 1 GeV. The mesonic final state interactions are described in terms of the scalar form factors, which are obtained from unitarized chiral perturbation theory. Employing generalized light-cone distribution amplitudes, we compute the heavy-to-light transition using light-cone sum rules. Our approach simultaneously respects constraints from analyticity and unitarity, and also takes advantage of the power expansion in the and the strong coupling constant. [Copyright &y& Elsevier]

Abstract: We calculate the strong coupling constants of light pseudoscalar mesons with heavy baryons within the light cone QCD sum rules method. It is shown that sextet–sextet, sextet–antitriplet and antitriplet–antitriplet transitions are described by one universal invariant function for each class. A comparison of our results on the coupling constants with the predictions existing in literature is also presented. [ABSTRACT FROM AUTHOR]

Abstract: Using the recent results for the two-parton light-cone distribution amplitudes of the tensor meson, we calculate the form factors for the decays of into the light tensor mesons via the vector/axial–vector/tensor current with the light-cone sum rules. We also obtain the -dependence of the form factors. [ABSTRACT FROM AUTHOR]

In this paper, we calculate the electromagnetic form-factor of the π meson with the light-cone QCD sum rules. The numerical value $F_\pi^{p}(0) = 0.999\pm 0.001$ is in excellent agreement with the experimental data (extrapolated to the limit of zero momentum transfer or the normalization condition Fπ(0) = 1). For large momentum transfers, the values from the two sum rules are all comparable with the experimental data and theoretical estimations. [ABSTRACT FROM AUTHOR]

We present the first systematic analysis of the off-light-cone effects in correlators relevant for the extraction of the heavy-to-light form factors within the method of light-cone sum rules. In a model with scalar constituents, the correlator is calculated in two different ways: (i) by performing the expansion of the Bethe-Salpeter amplitude of the light meson near the light cone x 2 = 0 and (ii) by adopting the known solution for the Bethe-Salpeter amplitude which allows one to calculate the correlator without invoking any expansion. We demonstrate that the contributions to the correlator from the off-light-cone terms x 2 ≠ 0 are not suppressed by any large parameter compared to the contribution of the light-cone term x 2 = 0. For decays of heavy particles of mass in the range 1.5–5 GeV, the light-cone correlator is shown to systematically overestimate the full correlator, numerically the difference being 10–20%. [ABSTRACT FROM AUTHOR]

In this paper we study the semileptonic decays of the Bc meson in the light-cone sum rule (LCSR) approach. The result for each channel depends on the corresponding distribution amplitude (DA) of the final meson. For the case of Bc decaying into a pseudoscalar meson, to twist-3 accuracy only the leading twist distribution amplitude is involved if we start from a chiral current. If we choose a suitable chiral current in the vector meson case, the main twist-3 contributions are also eliminated and we can consider the leading twist contribution only. The leading twist distribution amplitudes of the charmonium and other heavy mesons are given by a model approach in a reasonable way. Employing this charmonium distribution amplitude we find a cross section $\sigma(e^+e^-\to{}J/\psi+\eta_c)\simeq{22.8}\text{fb}$ that is consistent with Belle and BaBar data. Based on this model, we calculate the form factors for various Bc decay modes in the corresponding regions. Extrapolating the form factors to the whole kinetic regions, we get the decay widths and branching ratios for various Bc decay modes including their τ modes when they are kinematically accessible. [ABSTRACT FROM AUTHOR]

In this paper, we take the point of view that the charmed axial-vector meson Ds1(2460) is the conventional meson and calculate the strong coupling constant in the framework of the light-cone QCD sum rules approach. The numerical values of strong coupling constants and are very large, and support the hadronic dressing mechanism. Just like the scalar mesons f0(980) and a0(980), the scalar meson Ds0(2317) and axial-vector meson Ds1(2460) may have small kernels of the typical meson size; the strong couplings to the hadronic channels (or the virtual mesons loops) may result in smaller masses than the conventional mesons in the constituent quark models, and enrich the pure states with other components. [ABSTRACT FROM AUTHOR]

By adopting two models of strange and antistrange quark distributions inside nucleon, the light-cone meson-baryon fluctuation model and the effective chiral quark model, we calculate the $D_s^+ - D_s^-$ asymmetry in photoproduction in the framework of heavy-quark recombination mechanism. We find that the effect of asymmetry of strange sea to the Ds asymmetry is considerable and depending on the different models. Therefore, we expect that with the further study in electroproduction, e.g. at HERA and CEBAF, the experimental measurements on the $D_s^+ - D_s^-$ asymmetry may impose a strong restriction on the strange-antistrange distribution asymmetry models. [ABSTRACT FROM AUTHOR]

We use the transverse-momentum dependence of the cross section for the diffractive dissociation of high energy pions to two jets to study some non-perturbative light-cone wave functions of the pion. We compare the predictions for this distribution by Gaussian and Coulomb wave functions as well as the wave function derived from a solution of the light-cone Flamiltonian in the singlet model. We conclude that this experimentally measured information provides a powerful tool for these studies. [ABSTRACT FROM AUTHOR]

The doubly charmed Ξ cc + + (c c u) state is the only listed baryon in PDG, which was discovered in the experiment. The LHCb collaboration gets closer to discovering the second doubly charmed baryon Ξ cc + (c c d) , hence the investigation of the doubly charmed/bottom baryons from many aspects is of great importance that may help us not only get valuable knowledge on the nature of the newly discovered states, but also in the search for other members of the doubly heavy baryons predicted by the quark model. In this context, we investigate the strong coupling constants among the Ξ cc + (+) baryons and π 0 (±) mesons by means of light cone QCD sum rule. Using the general forms of the interpolating currents of the Ξ cc + (+) baryons and the distribution amplitudes (DAs) of the π meson, we extract the values of the coupling constants g Ξ cc Ξ cc π . We extend our analyses to calculate the strong coupling constants among the partner baryons with π mesons, as well, and extract the values of the strong couplings g Ξ bb Ξ bb π and g Ξ bc Ξ bc π . The results of this study may help experimental groups in the analyses of the data related to the strong coupling constants among the hadronic multiplets. [ABSTRACT FROM AUTHOR]

At present, there are many experimental and theoretical results for J / ψ → η c + γ process, while the results are inconsistent based on different methods and considerations. In this paper, the light cone sum rules method is used in studying the radiative decay J / ψ → η c + γ. We give the transition form factor of this process based on the leading twist distribution amplitude of η c meson, with this form factor further obtain the decay width. Our result is consistent with those of other sum rules. A comparison of our result with others' about the decay width is also presented. [ABSTRACT FROM AUTHOR]

I discuss the renormalization-group equation governing the leading order light-cone distribution amplitude of the B-meson φB+(ω,μ) and its exact analytic solution. The solution displays two features concerning the asymptotic behaviour of φB+(ω,μ) for small and large values of ω. I comment on further applications and argue that the loss of normalizability is not a problem in practice. PACS: 12.38.Cy – 12.39.Hg – 12.39.St – 13.25.Hw [ABSTRACT FROM AUTHOR]

We calculate the gravitational form factors of the pion, σ meson, and ρ meson in the Nambu-Jona-Lasinio model of quantum chromodynamics. The canonical energy-momentum tensor (EMT) is used in their derivation, allowing the possibility of an antisymmetric contribution when the hadron has intrinsic spin. We show that the asymmetric graviton vertex arising from the canonical EMT satisfies a simpler Ward-Takahashi identity (WTI) than the symmetric graviton vertex of the Belinfante EMT. The necessity of fully dressing the graviton vertex through the relevant Bethe-Salpeter equation is demonstrated for observing both the WTI and a low-energy pion theorem. Lastly, we calculate static moments of the meson EMT decompositions, obtaining predictions for the meson mass radii. We find light cone mass radii of 0.27 fm for the pion, 0.32 fm for the σ, and 0.32 fm for the ρ. For the pion and ρ, these are smaller than the light cone charge radii, respectively 0.51 fm and 0.45 fm, while we have a σ charge radius of zero. Our light cone pion mass radius agrees with a phenomenological extraction from KEKB data. [ABSTRACT FROM AUTHOR]

We show that confinement in the quantum Ising model leads to nonthermal eigenstates, in both continuum and lattice theories, in both one (1D) and two dimensions (2D). In the ordered phase, the presence of a confining longitudinal field leads to a profound restructuring of the excitation spectrum, with the low-energy two-particle continuum being replaced by discrete "meson" modes (linearly confined pairs of domain walls). These modes exist far into the spectrum and are atypical, in the sense that expectation values in the state with energy E do not agree with the microcanonical (thermal) ensemble prediction. Single meson states persist above the two-meson threshold due to a surprising lack of hybridization with the (n≥4)-domain wall continuum, a result that survives into the thermodynamic limit and that can be understood from analytical calculations. The presence of such states is revealed in anomalous postquench dynamics, such as the lack of a light cone, the suppression of the growth of entanglement entropy, and the absence of thermalization for some initial states. The nonthermal states are confined to the ordered phase--the disordered (paramagnetic) phase exhibits typical thermalization patterns in both 1D and 2D in the absence of integrability. [ABSTRACT FROM AUTHOR]