Theoretical Status of K->pinunubar Decays

We present a concise review of the theoretical status of rare K->pinunubar decays in and beyond the standard model. Particular attention is thereby devoted to the recent calculation of the next-to-next-to-leading order corrections to the charm quark contribution of K^+->pi^+nunubar which removes the last relevant theoretical uncertainty from the K->pinunubar system.Comment: 5 pages, 2 figures, talk given at the XLIst Rencontres de Moriond QCD and High Energy Hadronic Interactions, La Thuile, Aosta Valley, Italy, March 18--25, 200

Something about Z-penguins I want to tell

We stress that in models with constrained minimal flavor violation large negative corrections to the flavor-changing Z-penguin amplitudes are excluded by the precision measurements of the Z -> b anti-b pseudo observables performed at LEP and SLC. The derived stringent range for the non-standard contribution to the universal Inami-Lim function C leads to tight two-sided limits for the branching ratios of all Z-penguin dominated flavor-changing K- and B-decays.Comment: Parallel talk at ICHEP08, Philadelphia, USA, July 2008. 5 pages, PDFLaTeX, 2 pdf figures and 1 table; v2: LaTeX template and references update

Recent Theoretical Developments in B -> X_s l^+ l^- Decays

We present a concise review of the theoretical status of the rare semileptonic B -> X_s l^+ l^- decays in the standard model. Particular attention is thereby devoted to the recent theoretical progress concerning, on the one hand the next-to-next-to-leading order QCD calculation and, on the other hand the analysis of phenomenological important subleading electroweak effects.Comment: 7 pages, 1 figure; Talk given at XXIXth Rencontres de Moriond Electroweak Interactions and Unified Theories, La Thuile, Aosta Valley, Italy, March 21-28, 200

Rare K- (vs.) B-decays

We present a concise review of the recent theoretical progress concerning the standard model calculations of the rare K_L -> pi^0 nu anti-nu, K^+ -> pi^+ nu anti-nu (gamma), anti-B -> X_s gamma, and anti-B -> X_s l^+ l^- decays. The current status and future of the model-independent analysis of rare K- and B-meson decays within constrained minimal-flavor-violation is also briefly discussed.Comment: 12 pages, 4 figures, to appear in the proceedings of the Kaon International Conference (KAON'07), Frascati, Italy, 21-25 May 2007, uses pdflatex; minor changes, final version accepted for publication on Po

How To Kill a Penguin

Within constrained minimal-flavor-violation the large destructive flavor-changing Z-penguin managed to survive eradication so far. We give a incisive description of how to kill it using the precision measurements of the Z -> b anti-b pseudo observables. The derived stringent range for the non-standard contribution to the universal Inami-Lim function C leads to tight two-sided limits for the branching ratios of all Z-penguin dominated flavor-changing K- and B-decays.Comment: 5 pages, 4 figures, 1 table, uses pdflatex, talk given at DIS 2007, Muenchen, Germany, April 15--20, 200

Recent Developments in Bbar -> X_s gamma

We present a concise review of the recent theoretical progress concerning the standard model calculation of the inclusive radiative Bbar -> X_s gamma decay. Particular attention is thereby devoted to the calculations of the next-to-next-to-leading order fixed-order O(alpha_s^2) contributions, non-local O(alpha_s Lambda/m_b) power corrections, and logarithmic-enhanced O(alpha_s^2) cut-effects to the decay rate. The current status of new physics calculations of the inclusive b -> s gamma mode is also briefly summarized.Comment: 7 pages, 2 figures, 1 table, based on invited talks given at the third meeting of the workshop ``Flavour in the era of the LHC'', CERN, Geneva, March 15--17, 2006 and at XLIInd Rencontres de Moriond, QCD and Hadronic Interactions, La Thuile, Italy, March 17--24, 2007, v2: minor modification