Presentation given at the Z' Exotica meeting, 19 Dec 2016. Study of the muon selection for the Z' analysis.
Knowledge of the electromagnetic interaction between a beam and the surrounding vacuum chamber is necessary in order to optimize the accelerator per-formance in terms of stored current. Many instability phenomena may occur in the machine because of the fields produced by the beam and acting back on itself as in a feedback device. Basically, these fields produce an extra voltage and energy gain, affecting the longitudinal dynamics, and a transverse momentum kick which deflects the...
We present a new analysis of the ratio ε'/ε which measures the direct CP violation in K→ππ decays. We use the 1/N_c expansion within the framework of the effective chiral lagrangian for pseudoscalar mesons. From general counting arguments we show that the matrix element of the operator Q_6 is not protected from possible large 1/N_c corrections beyond its large-N_c or VSA value. Calculating the 1/N_c corrections, we explicitly find that they are large and positive....
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.
A possibility of test of CPT and T-invariance in K-decays and testing C invariance in η and ϕ decays at the ϕ-factory in Frascati is considered. The most interesting and feasible experiments are discussed. Our consideration does not include a study of CP violation at a ϕ-factory. This main aim of a ϕ-factory is considered in details in other papers.
Analysis with the CHAIN-REDS Science Gateway of LEP Data from the ALEPH Collaboration year 2000 datafile ZD4001.12.ALRoberto Barbera, Bruno Riccardo, Carrubba Carla, Inserra Giuseppina, Maggi Marcello & Ricceri Rita
This is the software of a JSR 286 compliant "portlet" installed on the CHAIN-REDS Science Gateway that allows the analysis of the dataset mentioned in the title. Click on the External link below to be automatically re-directed to the execution page of the portlet on the Science Gateway.
The bulk of large radiative corrections to any process can be obtained by promoting coupling constants to be running ones and by including QED radiation at the leading logarithmic level via structure functions evoluted at some scale. The problem of fixing the proper scale in running coupling constants and in structure functions for non-annihilation processes is briefly addressed and the general solution is analyzed.