120703177
IS THE CRONIN’S REPRESENTATION CORRECT FOR THE PENGUIN OPERATOR?
It is shown that the Cronin’s operator, being used for a phenomenological description of non-loptonic K-meson decays within the effective chiral Lagrangian approach with non-linear realization of chiral SU(3)×SU(3) symmetry (so-called, chiral perturbation theory at the hadronic level), cannot be applied to the determination of the Penguin-operator (O5-operator) at the hadronic level. The affirmation is based on the proof of the violation of the low-energy theorem $\lim _{P + \to 0} \left\langle {\pi ^ + \left( {p_ + } \right)\pi ^ - \left( {p_ - } \right)\left| {O_5 } \right|K^0 \left( p \right)} \right\rangle = \frac{i}{{F_\pi }}\left\langle {\pi ^0 \left( p \right)\left| {O_5 } \right|K^0 \left( p \right)} \right\rangle $ which is valid within the framework of the Cronin’s representation. The violation of this low-energy theorem is obtained at the quark level and connected with the account of the low-energy interactions of pions caused by the overlap of wave functions of pions in the |π+π−> state in the...
53995887
Anomalous diffusion of pions at RHIC
After pointing out the difference between normal and anomalous diffusion, we consider a hadron resonance cascade (HRC) model simulation for particle emission at RHIC and point out that rescattering in an expanding hadron resonance gas leads to a heavy tail in the source distribution. The results are compared to recent PHENIX measurements of the tail of the particle emitting source in Au+Au collisions at RHIC. In this context, we show how can one distinguish experimentally the anomalous diffusion of hadrons from a second order QCD phase transition.
121143868
Chiral anomalies in non-leptonic decays within chiral perturbation theory at the quark level
Abstract By the example of the K + → π + π 0 γ decay the contribution of chiral anomalies to non-leptonic weak decays of K -mesons has been investigated at the quark level. The theoretical prediction for the probability of the K + → π + π 0 γ decay with the direct emission of a photon is B ( K + → π + π 0 γ (DE)) anom ⩽(1.1±0.2)×10 −5 . It is stressed that the mechanism of the ΔI= 1 2 transition in the K + → π + π 0 γ decay differs from that governing the enhancement of the ΔI= 1 2 transitions in the K 0 → π + π − decay.
14996935
Scalar mesons in a chiral quark model with glueball
Ground-state scalar isoscalar mesons and a scalar glueball are described in a U(3) × U(3) chiral quark model of the Nambu-Jona-Lasinio (NJL) type with’ t Hooft interaction. The latter interaction produces singlet-octet mixing in the scalar and pseudoscalar sectors. The glueball is introduced into the effective meson Lagrangian as a dilaton on the base of scale invariance. The mixing of the glueball with scalar isoscalar quarkonia and amplitudes of their decays into two pseudoscalar mesons are shown to be proportional to current quark masses, vanishing in the chiral limit. Mass spectra of the scalar mesons and the glueball and their main modes of strong decay are described.
123677901
Chiral symmetry breaking in QCD with linearly rising confinement potential
SummaryChiral symmetry breaking is explored within QCD with linearly rising confinement potential at the Nambu-Jona-Lasinio (NJL) prescription. The dynamical quark mass is obtained from the gap equation in terms of the string tension σ, σ,i.e.m=2蜰σ/π=0.33 GeV at σ=0.27 GeV2. The phenomenological constants of the NJL local four-quark interactionsG1 andG2 are found equal and expressed in terms of the string tension and the confinement radius. It is shown that the spectra of low-lying quark-antiquark collective excitations coincide with those predicted by the NJL model.
117212623
Constituent quark-based linear $\sigma$ model (L$\sigma$M) quark and scalar mesons, vector meson dominance
After describing the SU(2) linear sigma model (L$\sigma$M), we dynamically generate it using the B.W. Lee null tadpole sum (characterizing the true vacuum) together with the dimensional regularization lemma. Next we generate the chiral-limiting (CL) nonstrange and strange constituent quark masses ${\hat m}=325.7$ MeV; $m_s=486$ MeV away from the CL. Finally, we study vector meson dominance (VMD) and the pion, kaon charge radii and the loop-order $\rho\to\pi\gamma$, $\pi^0\to\gamma\gamma$ amplitudes in the quark model. Lastly, we verify this procedure using tree-order VMD graphs.
118401873
New simple explicit solutions of perfect-fluid hydrodynamics and phase-space evolution
New exact solutions of relativistic perfect-fluid hydrodynamics are presented, including the first family of exact rotating solutions. The method used to search for them is a simultaneous investigation of the relativistic hydrodynamical equations and the collisionless Boltzmann equation. Possible connections to the evolution of hot and dense partonic matter in heavy-ion collisions is discussed.
118504696
Exact solutions of relativistic perfect fluid hydrodynamics for a QCD Equation of State
We generalize a previously known class of exact analytic solutions of relativistic perfect fluid hydrodynamics for the first time to arbitrary temperature-dependent Equation of State. We investigate special cases of this class of solutions, in particular, we present hydrodynamical solutions with an Equation of State determined from lattice QCD calculations. We discuss the phenomenological relevance of these solutions as well.