5,321 research outputs found
New Analysis of the Delta I = 1/2 Rule in Kaon Decays and the B_K Parameter
We present a new analysis of the Delta I = 1/2 rule in K --> pi pi decays and
the B_K parameter. We use the 1/N_c expansion within the effective chiral
lagrangian for pseudoscalar mesons and compute the hadronic matrix elements at
leading and next-to-leading order in the chiral and the 1/N_c expansions.
Numerically, our calculation reproduces the dominant Delta I = 1/2 K --> pi pi
amplitude. Our result depends only moderately on the choice of the cutoff scale
in the chiral loops. The Delta I = 3/2 amplitude emerges sufficiently
suppressed but shows a significant dependence on the cutoff. The B_K parameter
turns out to be smaller than the value previously obtained in the 1/N_c
approach. It also shows a significant dependence on the choice of the cutoff
scale. Our results indicate that corrections from higher order terms and/or
higher resonances are large for the Delta I = 3/2 K --> pi pi amplitude and the
(|Delta S| = 2) K^0 -- anti K^0 transition amplitude.Comment: 50 pages, LaTeX, 13 eps figure
A Survey of the Confirmation Instruction of the Children within a Pastoral Conference
Confirmation .instruction of children is the foundation of the work of the pastor. During his period of contact with the catechumens he can strengthen the personal Christianity of the children. He has the children in the time of their lives when their minds are eager and susceptible. A good catechist through his instruction lays a solid foundation for a congregation of staunch believers in future years. Good confirmation instruction makes the preaching more efficient, makes the work with troubled souls easier, and increases the spirit of love between pastor and catechumens. A bad catechist will usually produce contrary results. The purpose of the paper is to make a survey of the confirmation instruction which the children of a pastoral conference are receiving today
The Structure of Space-Time Emerging from the Two-Superbody Problem in Chern Simons Supergravity
We show that the exact solution of the two_superbody problem in N=2 Chern
Simons Supergravity in 2+1 dimensions leads to a supermultiplet of space-times.
This supersymmetric space-time is characterized by the two gauge invariant
observables of the super Poincare' group, which may be viewed as the Casimir
invariants of an equivalent one-superbody state. The metric of this space-time
supermultiplet can be cast into the form of the metric for a spinning cone in
which the coordinates do not commute or for a spinning cone with an additional
finite discrete dimension. Some of the interesting features of this universe
and their possible physical implications are discussed in the light of a
corresponding observation by Witten.Comment: 10 pages, LaTe
Analyzing epsilon'/epsilon in the 1/N_c Expansion
We present a recent analysis of epsilon'/epsilon in the 1/N_c expansion. We
show that the 1/N_c corrections to the matrix element of Q_6 are large and
positive, indicating a Delta I=1/2 enhancement similar to the one of Q_1 and
Q_2 which dominate the CP conserving amplitude. This enhances the CP ratio and
can bring the standard model prediction close to the measured value for central
values of the parameters.Comment: One reference corrected. 5 pages, talk presented by P.H. Soldan at
the 3. International Conference on B Physics and CP Violation, Taipei,
Taiwan, December 3 - 7, 1999. Slightly expanded version of the article
submitted to the proceeding
General overview of the e-learning at the Saxony
Today, many universities around the world give e-learning services via internet. The developments around the e-learning at universities in Saxony has increased vigorously in recent years. This paper reflects of general overview of the E-Learning at the Saxony. Now more 50,000 members of eleven Saxonian colleges and universities are currently as a common educational environment uses sharing the OPAL learning platform, which makes the system one of the most frequently used e-learning technologies in the German
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