Related papers: QUARK OFF-SHELL EFFECTS IN FLAVOUR-CHANGING DECAYS
The effect of electric and color neutrality on 2-flavor color superconductivity has been investigated. It has been found that the effect of the charge neutrality on a 2-flavor quark system is very different from that on a 3-flavor system.…
We argue that light quark loops produce a paramagnetic suppression of infrared-sensitive order parameters such as <qq>, as the number N_f of light fermions increases. The possibly strong dependence of <qq> on N_f is related to the observed…
It is argued that the topcolor models recently proposed by Hill [1] may face significant constraints from flavor-changing neutral current processes (such as $B-\bar{B}$ mixing) unless the mixing angles between down-type quarks are small.…
A brief introduction to the effective Lagrangian treatment of QCD (in the sense of using fields representing physical particles rather than quarks and gluons) will be given. The historical evolution of the subject will be discussed. Some…
The effect of non-zero c quark mass on b quark HQET Lagrangian, up to 1/m_b level, is calculated at two loops. The results are expressed in terms of dilogarithmic functions of m_c/m_b. This calculation involves on-shell two-loop…
Leptoquarks (LQs) are predicted within Grand Unified Theories and are well motivated by the current flavor anomalies. In this article we investigate the impact of scalar LQs on Higgs decays and oblique corrections as complementary…
We present results for mass effects coming from secondary radiation of heavy quark pairs related to gluon splitting in the thrust distribution for e+e- collisions. The results are given in the dijet limit where the hard interaction scale…
Extending the SU(3) flavour symmetry breaking expansion from up, down and strange sea quark masses to partially quenched valence quark masses allows an extrapolation to the charm quark mass. This approach leads to a determination of charmed…
We will discuss here some of the recent results obtained from lattice simulations of QCD at non-zero temperature. Such calculations aim at a quantitative understanding of the thermodynamics of strongly interacting matter in equilibrium. We…
In this work, we study the radiative decay of heavy quarkonium states by using the effective Lagrangian approach. Firstly, we construct the spin-breaking terms in the effective Lagrangian for the $nP\leftrightarrow mS$ transitions and…
The mass sensitivity of the chiral phase transition of QCD with and without axial $U_A(1)$-symmetry breaking at vanishing and finite quark chemical potential is investigated. To focus on the low-energy sector of QCD, a quark-meson model…
We construct the chiral Lagrangians relevant in studies of the ground-state octet baryon masses up to $\mathcal{O}(a^2)$ by taking into account discretization effects and calculate the masses up to $\mathcal{O}(p^4)$ in the…
I review highlights of recent results in quark-flavor physics and heavy-quark spectroscopy from lattice QCD, with emphasis on $B$-meson decays and excited and exotic charmonium states.
In this work we study the flavor changing neutral current(FCNC) decays of the top quark, $t\to c\gamma$ and $t\to c g$. The Standard Model, predictions for the branching ratios of these decays are about $\sim 5\times 10^{-14}$, and $\sim…
The combined effective low energy QCD Lagrangians of Nambu -- Jona-Lasinio (NJL) and 't Hooft are supplemented with eight-quark interactions. This work is a follow-up of recent findings, namely (i) the six quark flavour determinant 't Hooft…
The chromo-electromagnetic field is produced due to the motion of partons in a quark-gluon plasma created by relativistic heavy-ion collisions. The fluctuations in the produced chromo-electromagnetic field are important, since they cause…
We study the role of diquarks in light baryons through point to point baryon correlators. We contrast results from quenched simulations with ones with two flavors of dynamical overlap fermions. The scalar, pseudoscalar and axial vector…
In an effective Lagrangian approach to QCD we nonperturbatively calculate an analytic approximation to the decay rate of a false vacuum per unit volume, $\Gamma/V$. We do so for both zero and high temperature theories. This result is…
The effective quark interactions that break explicitly the chiral SU(3)_L X SU(3)_R and U_A(1) symmetries by current-quark mass source terms are considered in NLO in $N_c$ counting. They are of the same order as the 't Hooft flavor…
Effects of heavy sea quarks on the low energy physics are described by an effective theory where the expansion parameter is the inverse quark mass, 1/$M$. At leading order in 1/$M$ (and neglecting light quark masses) the dependence of any…