Threshold πNIsospin Violation

Isospin Violation in Threshold πN Scattering

We discuss the electromagnetic corrections to the πN scattering lengths generated by minimal e. m. coupling from a knowledge of the low energy expansion of the πN elastic scattering amplitude as well as from the nucleon and ∆ pole terms, all taken for purely strong interactions. We assume the heavy baryon limit; the e. m. and axial form factors and masses are assumed to have their empirical val...

Violation of Bell Inequalities as a Violation of Fair Sampling in Threshold Detectors

Photomultiplier tubes and avalanche photodiodes, which are commonly used in quantum optic experiments, are sometimes referred to as threshold detectors because, in photon counting mode, they cannot discriminate the number of photoelectrons initially extracted from the absorber in the detector. We argue that they can be called threshold detectors on more account than that. We point out that thei...

Probe of CP Violation in e + e − → tt̄ Near Threshold

0 Probe of CP Violation in e + e − → tt̄ Near Threshold ∗

We report our theoretical study on how to probe the anomalous CP-violating couplings of the top quark in the t ¯ t region at future e + e − linear colliders. We focus on the unique role of the t ¯ t threshold region.

Production of polarized tau pairs and tests of CP violation using polarized e+/- colliders near threshold.

.---. We consider the production of r pairs by electron-positron colliding beams -_ at the maximum cross section near the threshold. At this energy r pairs are produced mostly in the s-wave which implies that the spin of the 7 pairs are almost always pointing in the beam direction independent of the production angle. When both electrons and positrons are longitudinally polarized in the same dir...