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1.
The recent observation of higher quark combinations, tetraquarks and pentaquarks, is a strong indication of more exotic hadrons. Using Z2 and Z3 symmetries and standard model data, a general quark combination producing new hadronic states is proposed in terms of polygon geometries according to the Dynkin diagrams of  n affine Lie algebras. It has been shown that Z2,3 invariance is crucial in the determination of the mesonic or the baryonic nature of these states. The hexagonal geometry is considered in some details producing both mesonic and baryonic states. A general class of this family is also presented.  相似文献   

2.
Mass-dependent coupling constants are proposed for baryonic resonances in the relativistic mean-field model, according to the mass splitting of the SU (6) multiplet. With this choice the negative effective masses are avoided and the system remains nucleon dominated with moderate antidelta abundance.  相似文献   

3.
Nonlinear theory of electrostatic baryonic waves in ambiplasma   总被引:1,自引:0,他引:1  
A collisionless nonmagnetized ambiplasma consisting of Maxwellian gases of protons, antiprotons, electrons, and positrons is considered. The dispersion relation for electrostatic baryonic waves is derived and analyzed and exact expressions for the linear wave phase velocities are obtained. Two types of such waves are shown to be possible in ambiplasma: acoustic and plasma ones. Analysis of the dispersion relation has allowed the ranges of parameters in which nonlinear solutions should be sought in the form of solitons to be found. A nonlinear theory of baryonic waves is developed and used to obtain and analyze the exact solution to the basic equations. The analysis is performed by the method of a fictitious potential. The ranges of phase velocities of periodic baryonic waves and soliton velocities (Mach numbers) are determined. It is shown that in the plasma under consideration, these ranges do not overlap and that the soliton velocity cannot be lower than the linear velocity of the corresponding wave. The profiles of physical quantities in a periodic wave and a soliton (wave scores) are plotted.  相似文献   

4.
Theoretical basis for general stability criterion of relativistic shocks in baryonic matter is proposed. Different formulations of shock mechanical stability are considered and applied to the analysis of rarefaction shock hadronization transition.  相似文献   

5.
Theoretical basis for general stability criterion of relativistic shocks in baryonic matter is proposed. Different formulations of shock mechanical stability are considered and applied to the analysis of rarefaction shock hadronization transition.  相似文献   

6.
Multibaryons with strangeness, charm and bottom   总被引:1,自引:0,他引:1  
The spectra of baryonic systems with strangeness, charm and bottom are considered within a “rigid oscillator' version of the bound state soliton model. The static properties of multiskyrmions, of baryon number up to B=8, are calculated using the recently suggested rational map ansaetze as starting field configurations. The property of binding of flavoured mesons by an SU(2) skyrmion is proved rigorously within this model. Binding energy estimates are made of the states with largest isospin which can appear as negatively charged nuclear fragments and for states with zero isospin – fragments of “flavoured' nuclear matter. It is shown that for all types of flavour and for the isoscalar baryonic systems have a better chance to be stable against strong and electromagnetic interactions than those with nonzero isospin. Baryonic systems with charm or bottom quantum numbers are found to be bound more than strange baryonic systems. Received: 21 September 1999 / Revised version: 1 February 2000 / Published online: 27 November 2000  相似文献   

7.
The recent observation of higher quark combinations, tetraquarks and pentaquarks, is a strong indication of more exotic hadrons. Using Z_2 and Z_3 symmetries and standard model data, a general quark combination producing new hadronic states is proposed in terms of polygon geometries according to the Dynkin diagrams of ?_n affine Lie algebras. It has been shown that Z_(2,3) invariance is crucial in the determination of the mesonic or the baryonic nature of these states. The hexagonal geometry is considered in some details producing both mesonic and baryonic states. A general class of this family is also presented.  相似文献   

8.
Analytic solutions are presented for the hydrodynamic collimation of a relativistic fireball by a surrounding baryonic wind emanating from a torus. The opening angle is shown to be the ratio of the power output of the inner fireball to that of the exterior baryonic wind. The gamma ray burst 990123 might thus be interpreted as a baryon-poor jet (BPJ) with an energy output of order 10(50) erg or less, collimated by a baryonic wind from a torus with an energy output of order 10(52.5) erg, roughly the geometric mean of the BPJ and its isotropic equivalent.  相似文献   

9.
The partialdecay-rate asymmetries indicating the CP violating effects in two-body baryonic decays of B: - B: eystem are systematically studied. It turns out that the CP asymmetries are large in some processes, 1.6×l08, 5.5×l09 and 4.2 x 109 bb pairs are needed for testing the CP violation in Bd0 - Bd0 → pp, Δ0Δ 0 and Δ++Δ ++, respectively. It is impossible to detect the CP violating effects in those decays where penguin diagrams dominate.  相似文献   

10.
We compute the physical charges and discuss the properties of a large class of five-dimensional extremal AdS black holes by using the near horizon data. Our examples include baryonic and electromagnetic black branes, as well as supersymmetric spinning black holes. In the presence of the gauge Chern-Simons term, the five-dimensional physical charges are the Page charges. We carry out the near horizon analysis and compute the four-dimensional charges of the corresponding black holes by using the entropy function formalism and show that they match the Page charges.  相似文献   

11.
According to the Multiple Point Principle, our Universe is on the coexistence curve of two or more phases of the quantum vacuum. The coexistence of different quantum vacua can be regulated by the exchange of the global fermionic charges between the vacua, such as baryonic, leptonic, or family charge. If the coexistence is regulated by the baryonic charge, all the coexisting vacua exhibit the baryonic asymmetry. Due to the exchange of the baryonic charge between the vacuum and matter, which occurs above the electroweak transition, the baryonic asymmetry of the vacuum induces the baryonic asymmetry of matter in our Standard Model phase of the quantum vacuum. The present baryonic asymmetry of the Universe indicates that the characteristic energy scale, which regulates the equilibrium coexistence of different phases of quantum vacua, is about 106 GeV.  相似文献   

12.
The binding energies of baryonic systems with baryon numberB=2, 3, and 4 possessing heavy flavor, charm, bottom, or top, are estimated within the rigid oscillator version of the bound-state approach to chiral soliton models. Two tendencies are noted: the binding energy increases with increasing mass of the flavor and with increasingB. Therefore, the charmed or bottom baryonic systems have a better chance of being bound than do the strange baryonic systems discussed previously.  相似文献   

13.
We discuss a field-theoretical approach based on general-relativistic variational principle to derive the covariant field equations and hydrodynamic equations of motion of baryonic matter governed by cosmological perturbations of dark matter and dark energy. The action depends on the gravitational and matter Lagrangian. The gravitational Lagrangian depends on the metric tensor and its first and second derivatives. The matter Lagrangian includes dark matter, dark energy and the ordinary baryonic matter which plays the role of a bare perturbation. The total Lagrangian is expanded in an asymptotic Taylor series around the background cosmological manifold defined as a solution of Einstein’s equations in the form of the Friedmann–Lemaître–Robertson–Walker (FLRW) metric tensor. The small parameter of the decomposition is the magnitude of the metric tensor perturbation. Each term of the series expansion is gauge-invariant and all of them together form a basis for the successive post-Friedmannian approximations around the background metric. The approximation scheme is covariant and the asymptotic nature of the Lagrangian decomposition does not require the post-Friedmannian perturbations to be small though computationally it works the most effectively when the perturbed metric is close enough to the background FLRW metric. The temporal evolution of the background metric is governed by dark matter and dark energy and we associate the large scale inhomogeneities in these two components as those generated by the primordial cosmological perturbations with an effective matter density contrast δρ/ρ≤1δρ/ρ1. The small scale inhomogeneities are generated by the condensations of baryonic matter considered as the bare perturbations of the background manifold that admits δρ/ρ?1δρ/ρ?1. Mathematically, the large scale perturbations are given by the homogeneous solution of the linearized field equations while the small scale perturbations are described by a particular solution of these equations with the bare stress–energy tensor of the baryonic matter. We explicitly work out the covariant field equations of the successive post-Friedmannian approximations of Einstein’s equations in cosmology and derive equations of motion of large and small scale inhomogeneities of dark matter and dark energy. We apply these equations to derive the post-Friedmannian equations of motion of baryonic matter comprising stars, galaxies and their clusters.  相似文献   

14.
In this paper, we investigate an SU(3) extension of the chiral quark-meson model. The spectra of baryons with strangeness, charm, and bottom are considered within a “rigid oscillator” version of this model. The similarity between the quark sector of the Lagrangian in the model and the Wess-Zumino term in the Skyrme model is noted. The binding energies of baryonic systems with baryon numbers B=2 and 3 possessing strangeness or heavy flavor are also estimated. The results are in good qualitative agreement with those obtained previously in the chiral soliton (Skyrme) model.  相似文献   

15.
We present an analysis of the static properties of heavy baryons at next-to-leading order in the perturbative expansion of QCD. We obtain analytical next-to-leading order three-loop results for the two-point correlators of baryonic currents with one finite-mass quark field for a variety of quantum numbers of the baryonic currents. We consider both the massless limit and the HQET limit of the correlator as special cases of the general finite-mass formula and find agreement with previous results. We present closed-form expressions for the moments of the spectral density. We determine the residues of physical baryon states using sum-rule techniques.  相似文献   

16.
A model of phase transition between baryonic hadron and quark-gluon matter is elaborated. The spectrum of baryonic colourless bags is found. It is shown that the constraint of bag colourlessness is decisive for the phase transition to be realized.  相似文献   

17.
In this talk I report on recent work related to the dynamical generation of baryonic resonances, some made up from pseudoscalar meson-baryon, others from vector meson-baryon and a third type from two meson-one baryon systems. We can establish a correspondence with known baryonic resonances, reinforcing conclusions previously drawn and bringing new light on the nature of some baryonic resonances of higher mass.  相似文献   

18.
Static properties of multiskyrmions with baryon numbers up to 8 are calculated on the basis of the recently given rational map Ansätze. The spectra of baryonic systems with strangeness, charm, and bottom are considered within a “rigid oscillator” version of the bound state soliton model. It is suggested that the recently observed negatively charged nuclear fragment can be considered as a quantized strange multiskyrmion with B=6 or 7. In agreement with previous observations, baryonic systems with charm or bottom have a better chance of being bound by the strong interactions than do strange baryonic systems.  相似文献   

19.
Dark matters     
Despite the new results on the estimate of cosmological parameters, the need for dark matter, both baryonic and nonbaryonic, galactic and intergalactic, is still with us. For baryonic dark matter the remaining possibilities are mostly either intergalactic hot gas or massive compact halo objects. For nonbaryonic dark matter the most likely candidates are the so-called WIMPs, the prototype of which could be the lightest supersymmetric particle. These particles are actively searched for at accelerators and, in our neighborhood, through direct detection or by their annihilation products.  相似文献   

20.
We review gamma-ray observations that constrain antimatter – both baryonic and leptonic - in the Universe. Antimatter is probed through ordinary matter, with the resulting annihilation gamma-rays providing indirect evidence for its presence. Although it is generally accepted that equal amounts of matter and antimatter have been produced in the Big Bang, gamma-rays have so far failed to detect substantial amounts of baryonic antimatter in the Universe. Conversely, positrons are abundantly observed through their annihilation in the central regions of our Galaxy and, although a wealth of astrophysical sources are plausible, their very origin is still unknown. As both antimatter questions – the source of the Galactic positrons and the baryon asymmetry in the Universe - can be investigated through the low energy gamma-ray channel, the mission concept of a dedicated space telescope is sketched out.  相似文献   

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