相关论文: Paradoxes in Strange Quark Contributions to Hypero…
We employ the relativistic constituent quark model to give a unified description of the leptonic and semileptonic decays of pseudoscalar mesons (\pi, K, D, D_s, B, B_s). The calculated leptonic decay constants and form factors are found to…
Magnetic moments of baryons composed of light and strange quarks are computed for the first time through the only parameter of the model -- string tension $\sigma$. Resulting theoretical values differ from the experimental ones typically by…
A relativistic constituent quark model is adopted to give an unified description of the leptonic and semileptonic decays of pseudoscalar mesons (\pi, K, D, D_s, B, B_s). The calculated leptonic decay constants and form factors are found to…
We discuss interplay of the scalar and vector diquarks which decide the characteristics of the spin polarization as functions of $p_T$ and $x_F$ in the wide kinematical range. We demonstrate a significant effect of quark masses on the…
We study the possibility of explaining the recently found anomalies in B-meson decays within scenarios with a composite Higgs boson. This class of models provides a natural way to fit the experimental results, interpreting the anomalies as…
The strangeness-changing ($\Delta S = 1$) weak baryon-baryon interaction is studied through the nonmesonic weak decay of double-$\Lambda$ hypernuclei. Besides the usual nucleon-induced decay $\Lambda N \to N N$ we discuss novel…
The form factors parameterizing the B_c semileptonic matrix elements can be related to a few invariant functions if the decoupling of the spin of the heavy quarks in B_c and in the mesons produced in the semileptonic decays is exploited. We…
We discuss the possibilities of extracting the constraints on New Physics by using the current data on the leptonic and semileptonic decays of pseudoscalar mesons. In doing so we use a general low energy Lagrangian that besides the vector…
We discuss magnetic moments of the $J=3/2$ baryons based on an earlier model for the baryon magnetic moments, allowing for flavor symmetry breaking in the quark magnetic moments as well as a general quark spin structure. From our earlier…
Hyperon nonleptonic decays that change strangeness by two units, such as $\Xi\to N\pi$ and $\Omega^-\to nK^-,\Lambda\pi^-,\Sigma^{(*)}\pi$, are highly suppressed in the standard model. Only a few of them have been searched for to date,…
Spin effects in exclusive and inclusive reactions provide an essential new dimension for testing QCD and unraveling hadron structure. Remarkable new experiments from SLAC, HERMES (DESY), and the Jefferson Laboratory present many challenges…
Measurements of the net polarization of $\Lambda$ and $\bar{\Lambda}$ hyperons at the Relativistic Heavy Ion Collider (RHIC) have stimulated much interest in how strange quarks might align their spin with the vorticity of the matter created…
We investigate the semileptonic hyperon decays within the framework of the self-consistent SU(3) chiral quark-soliton model ($\chi$QSM). We take linear $1/N_c$ rotational as well as linear $m_s$ corrections into account and apply the…
We summarize the present status of the theories of spin fluctuations in dealing with the anomalous or non-Fermi liquid behavior and unconventional superconductivity in strongly correlated electron systems around their magnetic instabilities…
The strange magnetic moment of the proton is small in the chiral quark model, because of a near cancellation between the quantum fluctuations that involve kaons and $s$-quarks and loops that involve radiative transitions between strange…
We evaluate semileptonic decays of spin-1/2 and spin-3/2 doubly heavy $cb$ baryons. The decays are driven by a $c\to s,d$ transition at the quark level. We check our results for the form factors against heavy quark spin symmetry constraints…
We study the semileptonic decays of the lowest-lying $bc$ baryons to the lowest-lying $cc$ baryons ($\Xi_{bc}^{(\prime*)}\to \Xi_{cc}^{(*)}$ and $\Omega_{bc}^{(\prime*)}\to \Omega_{cc}^{(*)}$), in the limit $m_b, m_c \gg…
The relativistic and quantum theoretical explanations of the magnetic moment anomaly of the electron (or proton) show that it is a complicated function of the fine structure constant. In this work, a simple non-relativistic approach shows…
The formalism and applications of chiral perturbation theory for hadrons containing a single heavy quark are discussed. We emphasize the utility of working directly with the velocity dependent ``super'' fields which appear in the chiral…
Quenched and unquenched quark models predict very different patterns for the spectrum of the low excited hyperon states. Evidence is accumulating for the existence of some new hyperon resonances, such as a $\Sigma^*$ of spin-parity…