Phenomenology of ${\epsilon }_K$ Beyond Leading Logarithms

Abstract

I present the QCD short distance coefficient ${\eta }_3$ of the $\Delta S=2$ hamiltonian in the \emph{next-to-leading order} (NLO) of renormalization group improved perturbation theory. Since now all QCD-factors ${\eta }_1$, ${\eta }_2$ and ${\eta }_3$ are known with NLO accuracy, a much higher precision in the analysis of ${\epsilon }_K$ can be achieved. The CKM phase $\delta$, $|V_{td}|$ and the mass difference $\Delta m_{B_s}$ in the ${\text{B}}_s^0-{\overline{\text{B}}}_s^0$-system are predicted from the measured values of ${\epsilon }_K$ and $\Delta m_{B_d}$. Finally I briefly look at the \kkmd. This work has been done in collaboration with Stefan Herrlich.

Comments: 3 pages, talk given at the EPS-HEP-95 conference in Brussels, uses LaTeX 2e, one figure included. Get a complete PostScript Version from ftp://feynman.t30.physik.tu-muenchen.de/pub/preprints/tum-92-95.ps.gz