Related papers: Studying the Sivers function by model calculations
The chiral constituent quark model ($\chi$CQM) has been extended to calculate the flavor structure of the nucleon through the meson-nucleon sigma terms which have large contributions from the quark sea and are greatly affected by chiral…
We construct a realistic field-theoretic model for the structure of a heavy meson in the heavy quark limit. The model is fully covariant and satisfies heavy quark symmetry. The Isgur-Wise function, the decay constant, and the axial vector…
We introduce and study categorical realizations of quivers. This construction generalizes comma categories and includes representations of quivers on categories, twisted representations of quivers and bilinear pairings as special cases. We…
Chiral symmetry restoration of quarks is investigated at finite density in quantum chromodynamics. The effective quark mass is calculated with the Schwinger-Dyson equation in the real-time formalism without the instantaneous exchange…
The bound state of constituent quarks forming a $Qqq$ composite baryon is investigated in a QCD-inspired effective light-front model. The light-front Faddeev equations are derived and solved numerically. The masses of the spin 1/2 low-lying…
The extra contributions due to an extra generation of vector-like quarks to the isospin symmetry breaking observable associated with the radiative B->K^* \gamma decay is obtained. It is shown that this additional contribution is sensitive…
A $SU(3)_Q \times SU(3)_u \times SU(3)_d$ invariant scalar potential breaking spontaneously the quark flavour symmetry can explain the standard model flavour puzzle. The approximate alignment in flavour space of the vacuum expectation…
Sum rules -- relating the static quark potential V(R) to the spatial distribution of the action and energy in the colour fields of flux-tubes -- are applied in three ways: 1) To extract generalised beta-functions: 2) As a consistency check…
We consider the problems of calculating the dynamical order parameter two-point function at finite temperatures and the one-point function after a quantum quench in the transverse field Ising chain. Both of these can be expressed in terms…
We study the equation of state in two-flavor QCD at finite temperature and density. Simulations are made with the RG-improved gluon action and the clover-improved Wilson quark action. Along the lines of constant physics for $m_{\rm…
We present a QCD sum rule calculation of the Isgur-Wise form-factor tau_1(v.v') and tau_2(v.v') for the semileptonic decays B->D_1(2420)l\bar\nu and B->D_2^*(2460)l\bar\nu in the framework of heavy quark effective theory. These two…
The goal of this thesis is to calculate properties of D-Mesons with QCD-Sum-Rules in order to understand the nature of D-Mesons with positive parity. The result is that such D-Mesons most probably are Mesons with a four quark rather than a…
This review article discusses the experimental and theoretical status of various Parton Model sum rules. The basis of the sum rules in perturbative QCD is discussed. Their use in extracting the value of the strong coupling constant is…
The spin and orbital angular momentum carried by different quark flavors in the nucleon are calculated in the SU(3) chiral quark model with symmetry-breaking. The similar calculation is also performed for other octet and decuplet baryons.…
The $D_4$ flavor model based on $\mathrm{SU}(3)_C \otimes \mathrm{SU}(3)_L \otimes \mathrm{U}(1)_X$ gauge symmetry that aims at describing quark mass and mixing is updated. After spontaneous breaking of flavor symmetry, with the constraint…
We analyze the connections between the quark model (QM) and the description of hadrons in the low-momentum limit of heavy-baryon effective field theory in QCD. By using a three-flavor-index representation for the effective baryon fields, we…
We employ QCD sum rules to calculate the $J/\psi DD^*$ form factors and coupling constant by studying the three-point $J/\psi D^*D$ correlation function. We find that the momentum dependence of the form factor depends on the off-shell…
In the QCD Sum Rule determination of $m_s$ using the two-point correlator of divergences of $\Delta S=1$ vector currents, the final uncertainty on $m_s$ is mainly due to the hadronic spectral function. Using a specific parameterization…
We perform the global analysis of polarized Semi-Inclusive Deep Inelastic Scattering (SIDIS), pion-induced polarized Drell-Yan (DY), and $W^\pm/Z$ boson production data and extract the Sivers function for $u$, $d$, $s$ and for sea-quarks.…
We investigate some QCD corrections that contribute to the Gross-Llewellyn Smith (GLS) sum rule, but have not been included in previous analyses of it. We first review the techniques by which the xF3 structure function is extracted from…