14072015
Scalar Mesons and Glueballs in a Chiral U(3)xU(3) Quark Model with 't Hooft Interaction
In a U(3)x U(3) quark chiral model of the Nambu-Jona-Lasinio type with the 't Hooft interaction, the ground scalar isoscalar mesons and a scalar glueball are described. The glueball (dilaton) is introduced into the effective meson Lagrangian written in a chirally symmetric form on the base of scale invariance. The singlet-octet mixing of scalar isoscalar mesons and their mixing with the glueball are taken into account. Mass spectra of the scalar mesons and glueball and their strong decays are described.
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...
121275856
Quaternionic form of Maxwell’s equations with sources
122429057
Existence of the sigma meson below 1-GeV and f0(1500) glueball
On the basis of a simultaneous description of the isoscalar s-wave channel of the $\pi\pi$ scattering (from the threshold up to 1.9 GeV) and of the $\pi\pi\to K\bar{K}$ process (from the threshold to $\sim$ 1.4 GeV) in the model-independent approach, a confirmation of the $\sigma$-meson at $\sim$ 665 MeV and an indication for the glueball nature of the $f_0(1500)$ state are obtained. It is shown that the large $\pi\pi$-background, usually obtained, combines, in reality, the influence of the left-hand branch-point and the contribution of a very wide resonance at $\sim$ 665 MeV. The coupling constants of the observed states with the $\pi\pi$ and $K\bar{K}$ systems and lengths of the $\pi\pi$ and $K\bar{K}$ scattering are obtained.
118774621
Pion nucleon coupling constant, Goldberger-Treiman discrepancy and $\pi N$ $\sigma$ term
We start by studying the Goldberger-Treiman discrepancy (GTd) $\Delta = (2.259\pm 0.591)%$. Then we look at the $\pi N$ $\sigma$ term, with the dimensionless ratio $\sigma_N/2m_N=3.35%$. Finally we return to predicting (via the quark model) the $\pi N$ coupling constant, with GTd $\Delta\to 0$ as $m_q\to m_N/3$.
121077448
Quark model of superconducting type and nondiagonal P-A transitions
ConclusionsWe discuss the obtained results. We note that the solution to the problem of the elimination of the unphysical interactions that arise through the P-A diagnonalization has been obtained at the prescriptional level. We have found that to eliminate the unphysical vertices due to the P-A diagnonalization, it is sufficient to replace the effective Lagrangian (22) by the Pauli-Villars regularized Lagrangian (33). The regularization is needed because of the nonuniqueness of the calculation of the individual quark diagrams that describe the new interaction vertices. The Pauli-Villars regularization corresponds to subtraction from the quark diagram of a quantity determined by the same diagram but in which all the masses of the virtual quarks are replaced by the masses of the fermions — the regularizers M. Application of the regularization for the complete effective Lagrangian has the consequence that an appropriate contribution of the regularizers is subtracted from any vertex that arises as a result of shift of the axial fields (4). This is sufficient for the correct description of the interaction vertices that arise from the P-A diagonalization.
18335343
Search for squeezed-pair correlations at RHIC
Squeezed correlations of particle–antiparticle pairs, also called back-to-back correlations (BBC), are predicted to appear if the hadron masses are modified in the hot and dense hadronic medium formed in high energy nucleus–nucleus collisions. Although well established theoretically, the squeezed-particle correlations have not yet been searched for experimentally in high energy hadronic or heavy ion collisions, clearly requiring optimized forms to experimentally search for this effect. Within a non-relativistic treatment developed earlier we show that one promising way to search for the BBC signal is to look into the squeezed correlation function of pairs of 's at RHIC energies, plotted in terms of the average momentum of the pair, . This variable's modulus, 2|K12|, is the non-relativistic limit of the variable Qbbc, introduced herewith. Some squeezing effects on the HBT correlation function are also discussed.
15716297
New exact solutions of relativistic hydrodynamics
A new class of simple and exact solutions of relativistic hydrodynamics is presented, and the consequences are explored in data analysis. The effects of longitudinal work and acceleration are taken into account in an advanced estimate of the initial energy density and the life-time of the reaction.