121574390
Multiperipheral and polyperipheral approaches to pionization
Abstract Introduction of Regge trajectories in addition to the pomeron, which appears in Mueller's approach to pionization, is shown to predict a small dip. The analysis is motivated by a multiperipheral approach. The question whether this approach may lead to an understanding of the peak in the pionic distribution or the asymmetry effect is discussed. A new (polyperipheral) approach based on the exchange of several chains is introduced in order to account for the observed effects. It leads naturally to Mandelstam cuts and is compared with a partonic picture.
92016891
Possible U- and V-Spin Selection Rules in Weak Interactions
As shown in the lectures by Profs. Joos and Mayer one can define three sorts of isotopic spins in SU(3). The first one is the usual isotopic spin T, the other ones are designated by U and V.
119442708
Gauge-invariant variational methods for Hamiltonian lattice gauge theories
This paper develops variational methods for calculating the ground-state and excited-state spectrum of Hamiltonian lattice gauge theories defined in the A/sub 0/ = 0 gauge. The scheme introduced in this paper has the advantage of allowing one to convert more familiar tools such as mean-field, Hartree-Fock, and real-space renormalization-group approximation, which are by their very nature gauge-noninvariant methods, into fully gauge-invariant techniques. We show that these methods apply in the same way to both Abelian and non-Abelian theories, and that they are at least powerful enough to describe correctly the physics of periodic quantum electrodynamics (PQED) in (2+1) and (3+1) space-time dimensions. This paper formulates the problem for both Abelian and non-Abelian theories and shows how to reduce the Rayleigh-Ritz problem to that of computing the partition function of a classical spin system. We discuss the evaluation of the effective spin problem which one derives the PQED and then discuss ways of carrying out the evaluation of the partition function for the system equivalent to a non-Abelian theory. The explicit form of the effective partition function for the non-Abelian theory is derived, but because the evaluation of this function is considerably more complicated than the one derived in the Abelianmore » theory no explicit evaluation of this function is presented. However, by comparing the gauge-projected Hartree-Fock wave function for PQED with that of the pure SU(2) gauge theory, we are able to show that extremely interesting differences emerge between these theories even at this simple level. We close with a discussion of fermions and a discussion of how one can extend these ideas to allow the computation of the glueball and hadron spectrum.« less
121508600
Reggeon phases and the dual bootstrap program
Abstract Analyticity requirements lead to complex Regge vertices in multiparticle production amplitudes. Their effect is discussed within a dual, unitary and exchange-degenerate multi-Regge model. A resulting complex Regge vertex is incorporated in fixed-t model calculations of the reggeon bootstrap and the topological pomeron. The bootstrap condition for particle-particle scattering is unaffected but new j-plane singularities appear in Regge-Regge scattering amplitudes. The pomeron and reggeon intercepts determine the two parameters of our Regge vertex and admit two possible solutions: one is close to the naive phase rule (real vertex) and the other is complex and leads to a high lying non-leading pole in the pomeron channel.
122621587
MESON AND BARYON RESONANCES IN RELATIVISTIC SU(6)
115936426
UNITARY SYMMETRY AND THE LEPTONIC DECAYS OF HADRONS
The structure of the weak currents that appear in the leptonic decays is discussed in the light of unitary symmetry. The known leptonic interaction modes imply the inclusion of more currents than the ones derived from gauge invariance of the octet model. It is therefore suggested that the weak currents emerge from a higher symmetry scheme. The vector part of the interaction is obtained by CVC arguments and the axial-vector part by a Groldberger-Treiman approach. The fit with the experimental situation is discussed.
118159758
Study of $B^{0}_{s} \rightarrow D_s^{(*)+}D_s^{(*)-}$ and $B^{0}_{s} \rightarrow \phi\phi$ Decays at CDF
Under certain theoretical assumptions, the branching fraction of B{sub s}{sup 0} {yields} D{sub s}{sup (*)+}D{sub s}{sup (*)-} is directly sensitive to the relative decay width difference {Delta}{Lambda}{sub s}{sup CP}/{Lambda}{sub s} in the B{sub s}{sup 0} system, which is predicted to be sizable in the standard model. Using approximately 4 fb{sup -1} of data collected by the CDF II detector at the Tevatron p{bar p} collider, the CDF collaboration is currently performing an exclusive selection of B{sub s}{sup 0} {yields} D{sub s}{sup (*)+}D{sub s}{sup (*)-} signal candidates in several hadronic modes in order to provide a new branching fraction measurement. In contrast to former analyses, we start to have sensitivity in disentangling D{sub s}{sup (*)+}D{sub s}{sup (*)-}, enabling us to measure the branching fractions of B{sub s}{sup 0} {yields} D{sub s}{sup +}D{sub s}{sup -}, B{sub s}{sup 0} {yields} D{sub s}{sup (*)+}D{sub s}{sup -} and B{sub s}{sup 0} {yields} D{sub s}{sup (*)+}D{sub s}{sup (*)-} separately. Yet another interesting mode is the decay of the B{sub s}{sup 0} into a {phi} pair. This is a vector-vector decay dominated by the b {yields} s{ovr ss} penguin transition, which is a sensitive probe for possible new physics effects. Here we present a new measurement ofmore » the branching fraction based on a clean sample of about 300 B{sub s}{sup 0} {yields} {phi}{phi} signal events in a dataset with an integrated luminosity of 2.9 fb{sup -1}.« less
125542777
Measurement of the Exclusive and Inclusive Branching Fractions of $B^{0}_{s} \to D^{(*)+}_{s}D^{(*)-}_{s}$ Decays at CDF and its Implications on the Decay Width Difference in the $B^{0}_{s}-B^{-0}_{s}$ Meson System