118961029
Leptonic and semileptonic decays of heavy mesons.
which defines the leptonic decay constant, fM . (With this normalisation, fπ ≃ 131MeV.) In (1), Sf is the dressed quark propagator and ΓM(k;P ) is the Bethe-Salpeter amplitude for the bound state; M labels the meson whose flavour content is made explicit by the quark flavour labels, fi. For example, for the B -meson: f1 = u and f2 = b. The calculation of fM requires a knowledge of Sf and ΓM . The dressed-quark propagator has the general form Sf(p) = 1/[iγ · pAf(p) + Bf(p)]: a bare-quark is described by A(p) ≡ 1 and B(p) = m, where m is the current-quark mass. As described in Ref. [1], it is a characteristic of QCD elucidated in Dyson-Schwinger equation studies that for lightquarks; i.e., u-, dand s-quarks, Af (p ) and particularly Bf (p ) have a strong momentumdependence for p < 1GeV. This momentum-dependence is nonperturbative in origin. For the b-quark, however, the momentum-dependence ofAb(p ) andBb(p ) for all spacelikep is weak and mainly perturbative in origin. This suggests that, in phenomenological applications, it is a good approximation to write the dressed-b-quark propagator as
121608979
Heavy baryons in the relativistic quark model
Abstract We present a summary of results for exclusive decays of single and double heavy-flavored baryons in the relativistic three-quark model.
125377202
Weak decays of heavy mesons taking into account confinement of light quarks
198488906
The Box anomaly and radiative decays of eta(eta-prime) mesons
We report on a confined quark model calculation of the transition form factors for the radiative decays of \eta(\eta')->\gamma l^+l^- and \eta(\eta')->\gamma\pi^+\pi^-. The \eta-\eta' mixing angle \theta_P is determined from the set of data on the electromagnetic \eta(\eta') decays. It is found that \theta_P\sim -16.5. The analysis of the dipionic mass distribution in the decay \eta'->\gamma\pi^+\pi^- confirms the existence of a non-resonant contribution which is the box anomaly.
117141257
Multiquark states in the covariant quark confinement model
This talk reviews the last applications of the covariant quark model for studying the properties of the multiquark states: B_s-meson (quark-antiquark state), light baryons (three-quark states) and tetraquark (four-quark state). The form factors of the B(B_s)-> P(V)-transitions are evaluated in the full kinematical region of momentum transfer squared. The widths of some B_s-nonleptonic decays are calculated. The static properties of the proton and neutron, and the \Lambda-hyperon (magnetic moments and charge radii) and the behavior of the nucleon form factors at low momentum transfers are described. The consequences of treating the X(3872) meson as a tetraquark bound state are explored. The decay widths of the observed channels X->J/\psi+2\pi (3\pi) and X-> \bar D^0 + D^0+\pi^0 via the intermediate off--shell states X-> J/\psi+\rho(\omega) and X-> \bar D + D^* are calculated. Its one-photon decay X-> \gamma+ J/\psi is also analyzed.
6599022
LEPTONIC AND SEMILEPTONIC DECAYS OF PSEUDOSCALAR MESONS
Abstract We employ the relativistic constituent quark model to give a unified description of the leptonic and semileptonic decays of pseudoscalar mesons ( π , K , D , D s , B , B s ). The calculated leptonic decay constants and form factors are found to be in good agreement with available experimental data and other approaches. We reproduce the results of spin-flavor symmetry in the heavy quark limit.
2325056
A non-geometrical approach to quantum gravity
Some results of author's work in a non-geometrical approach to quantum gravity are reviewed here, among them: a quantum mechanism of classical gravity giving a possibility to compute the Newton constant; asymptotic freedom at short distances; interaction of photons with the graviton background leading to the important cosmological consequences; the time delay of photons due to interactions with gravitons; deceleration of massive bodies in the graviton background which may be connected with the Pioneer anomaly and with the problem of dark matter.
17217393
Superspace without torsion and the composite fundamental fermions
(N=2)-superspace without torsion is described, which is equivalent to an 8-space with a discrete internal subspace. A number and a character of ties determine now an internal symmetry group, while in the supersymmetrical models this one is determined by an extension degree N. Such a model can be constructed for no less than 4 generations of the two-component fundamental fermions. Analogues of the Higgs fields appear in the model naturally after transition to the Grassmannian extra coordinates. The connection between discrete and continues internal symmetries of the model is discussed. If one considers gravity as embedding the curved 4-space into a 12-dimensional flat space, a U(1)-symmetry appears transformations of which should be connected with the ones of SU(2)-group. If super-strong interacting gravitons are constituents of the composite fermions, all this may open us another way to unify the known interactions. The main feature of this new approach may be the external see of gravitons underlying an internal structure of particles; the lack of any divergencies would be due the Planckian spectrum of external gravitons.
14263635
SUPER-STRONG INTERACTING GRAVITONS AS A MAIN ENGINE OF THE UNIVERSE WITHOUT EXPANSION OR DARK ENERGY
The basic cosmological conjecture about the Dopplerian nature of redshifts may be false if gravitons are super-strong interacting particles. A quantum mechanism of classical gravity and the main features of a new cosmological paradigm based on it are described here.
119020799
Another possible interpretation of SN 1a data - without kinematics: Comments on the paper astro-ph/0402512 by A. Riess et al
It is shown here that for redshifts $z < 0.5$ the luminosity distance, which is predicted in author's model astro-ph/0005084 v2, fits well supernova observational data of astro-ph/0402512 by A.Riess et al. Discrepancies for higher $z$ would be explained in the model as a result of specific deformation of SN spectra due to a discrete character of photon energy losses. The model does not require any dark energy; it is based on the conjecture that gravitons are super-strong interacting particles fulfilling a flat non-expanding universe.
15370571
Gravitons as super-strong interacting particles, and low-energy quantum gravity
It is shown by the author that if gravitons are super-strong interacting particles and the low-temperature graviton background exists, the basic cosmological conjecture about the Dopplerian nature of redshifts may be false. In this case, a full magnitude of cosmological redshift would be caused by interactions of photons with gravitons. A new dimensional constant which characterizes one act of interaction is introduced and estimated. Non-forehead collisions with gravitons will lead to a very specific additional relaxation of any photonic flux. It gives a possibility of another interpretation of supernovae 1a data - without any kinematics. Of course, all of these facts may implicate a necessity to change the standard cosmological paradigm. Some features of a new paradigm are discussed here, too. A quantum mechanism of classical gravity based on an existence of this sea of gravitons is described for the Newtonian limit. This mechanism needs graviton pairing and "an atomic structure" of matter for working it, and leads to the time asymmetry. If the considered quantum mechanism of classical gravity is realized in the nature, than an existence of black holes contradicts to Einstein's equivalence principle. It is shown that in this approach the two fundamental constants - Hubble's and Newton's ones - should be connected between themselves. The theoretical value of the Hubble constant is computed. In this approach, every massive body would be decelerated due to collisions with gravitons that may be connected with the Pioneer 10 anomaly. It is shown that the predicted and observed values of deceleration are in good agreement. Some unsolved problems are discussed, so as possibilities to verify some conjectures in laser-based experiments.