Congruence from the operator’s point of view

A basic sanity property of a process semantics is that it constitutes a congruence with respect to standard process operators. This issue has been traditionally addressed by developing, for a specific process semantics, a syntactic format for operational semantics specifications. We suggest a novel, orthogonal approach, which focuses on a specific process operator and determines a class of congruence relations for this operator. To this end, we impose syntactic restrictions on Hennessy–Milner logic, so that a process semantics whose modal characterization satisfies those criteria is guaranteed to be a congruence with respect to the operator in question. We investigate alternative composition, action prefix, projection, encapsulation, renaming, and parallel composition with communication, in the context of both concrete and weak process semantics.

PARITY VIOLATION IN $d\vec \gamma \to np$ WITH PIONLESS EFFECTIVE THEORY

We consider a pionless effective theory with dibaryon fields for the description of the weak process involving two nucleons. We construct leading order Lagrangians that contain nucleon-dibaryon weak coupling constants. We calculate the physical observable in the photodisintegration of the deuteron at threshold and obtain the result in terms of the nucleon-dibaryon weak coupling constants. Relation to existing calculations is discussed.

MUON CAPTURE IN DEUTERIUM

Muon capture in deuterium, μ-+ D →νμ+n+n, is a weak process of fundamental importance. The capture rate depends critically on the spin configuration of the initial (μ D ) state, which is in turn related closely to the availability of having two nearby deuteron nuclei. In this paper, we calculate the capture rates from the doublet [Formula: see text] and quartet [Formula: see text] hyperfine states. In addition to using the gaseous or liquid deuterium target, we wish also to propose to employ the deuterated target such as PdD or TiD to carry out the muon capture measurement, since it is known that the transition metals such as palladium (Pd) or titanium (Ti) has unusually high deuteron (hydrogen) absorption properties.

NON-LEPTONIC WEAK TRANSITIONS WITH ΔI = 1/2 RULE IN DIQUARK-QUARK MODEL USING THE PAULI-GÜRSEY SYMMETRY

We study the non-leptonic weak transitions of ground state baryons in diquark-quark model. These weak transitions exhibit the ΔI = 1/2 rule, which is hard to account for in the standard weak process. If the diquark correlations are strong among flavor-antitriplet and spin-singlet pairs, we can make the weak transitions among diquarks followed by pion emission much stronger than the standard process. We estimate all the non-leptonic weak transitions of ground state baryons by assuming the Pauli-Gürsey symmetry together with the SU(6) wave functions. We can account for all the P-wave transition strengths quantitatively and hence the ΔI = 1/2 rule.