122493642
On the problem of D-meson leptonic and semileptonic decays
Abstract The infinite mass effective theory, when a heavy quark mass goes to infinity, and chiral perturbation theory at the quark level, based on the extended Nambu-Jona-Lasinio model, are applied for the description of form factors of semileptonic decay D→ K e + ν e and leptonic constant FD of D-mesons. The relation is derived connecting the form factor f+(0) with the ratio F D F π , which gives the estimate F D F π =1.21±0.17 . The slope parameter of the f+ form factor is calculated in agreement with experimental data.
121038747
EFFECTIVE CHIRAL LAGRANGIANS, THE QUARK MODEL OF SUPERCONDUCTIVITY TYPE AND THE PROBLEM OF P-A DIAGONALIZATION
The vertices appearing after the inclusion of P-A transitions and a subsequent diagonalization of the chiral Lagrangian are analyzed in the quark model of superconductivity type. These vertices can conditionally be divided into physical and nonphysical ones. It is shown that if the Pauli-Villars regularization is used, the contribution of the latter can be eliminated from the description of the physical processes. This is in full agreement with the experimental data.
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.
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.
121275856
Quaternionic form of Maxwell’s equations with sources
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...
16863322
Multi-boson correlations using wave-packets II
Abstract.
We investigate the analytically solvable pion-laser model, and generalize it to arbitrary multiplicity distributions.
We show that this kind of extension of the model is possible, but less interesting, than the already known one.
119143405
Detailed description of accelerating, simple solutions of relativistic perfect fluid hydrodynamics
In this paper we describe in full details a new family of recently found exact solutions of relativistic, perfect fluid dynamics. With an ansatz that generalizes the well-known Hwa-Bjorken solution we obtain a wide class of new exact, explicit, and simple solutions, which have a remarkable advantage as compared to presently known exact and explicit solutions: they do not lack acceleration. They can be utilized for the description of the evolution of the matter created in high energy heavy ion collisions. Because these solutions are accelerating, they provide a more realistic picture than the well-known Hwa-Bjorken solution, and give more insight into the dynamics of the matter. We exploit this by giving an advanced simple estimation of the initial energy density of the produced matter in high energy collisions, which takes acceleration effects, i.e., the work done by the pressure, and the modified change of the volume elements, into account. We also give an advanced estimation of the life-time of the reaction. Our new solutions can also be used to test numerical hydrodynamical codes reliably. In the end, we also give an exact, 1+1 dimensional, relativistic hydrodynamical solution, where the initial pressure and velocity profile is arbitrary, and we showmore » that this general solution is stable for perturbations.« less
125071872
Exact solutions of perfect fluid hydrodynamics: Theory and applications in high-energy experiments
Some exact and explicit solutions of the relativistic hydrodynamical equations are reviewed in context of high-energy heavy ion physics. Hydrodynamics is a powerful tool to describe the experimentally observed features (e.g. scaling laws) in the final state of high-energy collisions. Hydrodynamical solutions (both exact, analytic and numerical) can then be used to draw consequences on the initial state or the equation of state of the created matter. These findings can help to reach the ultimate goal of heavy-ion physics, the mapping of the phase structure of the strong interaction. In this paper we discuss exact and phenomenologically relevant solutions of hydrodynamics, and hint at some applications of them. We detail one important application: the estimation of the initial energy density from the observed final state.
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.
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.