Modern Physics Letters A

In a previously developed non-equilibrium model for hadronization of a quark gluon plasma, we study hadronic signals for plasma formation. We find that fragmentation of gluons into quark-antiquark pairs can lead to a strong enhancement of various antibaryon to baryon ratios if a baryon-rich quark gluon plasma is formed.

Pairs of conjugate nuclei with the same F-spin and ±F₀ values also have identical N_pN_n values. In the rare earth region, these ±F₀ pairs are symmetrically located with respect to the F₀=0, A=164 isobar and their empirical excitation energy spectra are found to be very similar. An IBM-2 Hamiltonian with constant parameters has such a built-in symmetry and can explain the general trends except for the bandhead energies.

Intriguing hints of possible observation of charmless baryonic modes of B decays have prompted us to make theoretical estimates of two and three body decay modes involving baryons in the final state. Bounds on the Kobayashi-Maskawa parameter V_ub can then be obtained.

We show that, in the path integral formalism, the Chern-Simons terms in string theories arise due to the anomalous behavior of the measure under gauge transformations.

We obtain a QCD sum rule for the kaon form factor at small Q². It determines, with a rather good accuracy, the kaon charge radius which is in agreement with the experimental value. We also discuss a sum rule for the difference .

We derive conditions for fermionic construction of N=0, 1 and 2 (super) conformal algebras, and obtain some solutions satisfying these conditions. In the N=2 case, these conditions can be simplified when supercurrents are written by complex fermions.

An extended particle is discussed as the hypothetical source of correlated electron and positron lines observed at GSI. The particle structure is described in the framework of the MIT bag model. A mechanism for copious production in the Coulomb field of heavy ions is proposed.

Analytical and numerical reexamination of SU(5)-like grand unified models is presented. Although an unmodified version of SU(5) is considered, we show that numerical calculations allow some of the models still to be experimentally admissible. Values for sin² θ_w, M_x and τ_p are corrected. It is especially shown that the above parameters depend on the mass spectrum of higher generations much more than Higgs-Yukawa couplings could affect them.

Using the charge of BRS transformation, we obtain Ward-Takahashi identity and full propagators from the BRS invariant bosonized chiral Schwinger model. It is shown from these propagators that there is a massive Proca field and a massless scalar field for a>1, where a is regarded as the bosonization ambiguities. Also, two propagators of Proca and scalar field both have positive norm states.

Non-observation of quarks or monopoles suggests their equivalence, as has been proposed within string and bag and other models and implied for QCD by the monopole solutions. The possible magnetic nature of quarks is investigated within a non-Abelian field theory with magnetic sources and fermions and color. The sources are shown to eliminate the non-analytic singularities of the field A_μ by a scale-setting mechanism which introduces a degenerate mass. The scale-setting mechanism follows from the requirement of gauge covariance by removal of the non-gauge covariant term which includes essential singulari-ties of . The low-lying hadron degenerate mass spectrum is obtained in terms of the degenerate mass and the colored symmetry.

We resolve renormalization problems, indicated in Ref. 1 and find explicit formulae for the spectrum of anomalous dimensions in 2d—quantum gravity. Comparison with combinatorial approximation of random surfaces and its numerical analyses shows complete agreement with all known facts.