New strategies for new physics search in B -> K*nu(nu)over-bar, B -> K nu(nu)over-bar and B -> X-s nu(nu)over-bar decays

作者：Altmannshofer Wolfgang^*; Buras Andrzej J; Straub David M; Wick Michael

来源：The Journal of High Energy Physics, 2009, 2009(4): 022.

DOI：10.1088/1126-6708/2009/04/022

• Rare Decays
• Beyond Standard Model
• B-Physics

The rare decay B -> K*nu(nu) over bar is regarded as one of the important channels in B physics as it allows a transparent study of Z penguin and other electroweak penguin effects in New Physics (NP) scenarios in the absence of dipole operator contributions and Higgs (scalar) penguin contributions that are often more important than Z contributions in B -> K*l(+)l(-) decays. We present a new analysis of B -> K*nu(nu) over bar with improved form factors and of the decays B -> K nu(nu) over bar and B -> X-s nu(nu) over bar in the SM and in a number of NP scenarios like the general MSSM, general scenarios with modified Z/Z' penguins and in a singlet scalar extension of the SM. We also summarize the results in the Littlest Higgs model with T-parity and a Randall-Sundrum (RS) model with custodial protection of left-handed Zd(i)(d) over bar (j) couplings. Our SM prediction BR(B -> K*nu(nu) over bar) = (6.8(-1.1)(+1.0)) x 10(-6) turns out to be significantly lower than the ones present in the literature. Our improved calculation BR(B -> X-s nu(nu) over bar) = (2.7 +/- 0.2) x 10(-5) in the SM avoids the normalization of the BR(B -> X(c)e (nu) over bar (e)) and, with less than 10% total uncertainty, is the most accurate to date. The results for the SM and NP scenarios can be transparently summarized in a (epsilon, eta) plane analogous to the known (rho) over bar, (eta) over bar) plane with a non-vanishing eta singalling this time not CP violation but the presence of new right-handed down-quark flavour violating couplings which can be ideally probed by the decays in question. Measuring the three branching ratios and one additional polarization observable in B -> K*nu(nu) over bar allows to overconstrain the resulting point in the (epsilon, eta) plane with (epsilon, eta) = (1, 0) corresponding to the SM. We point out that the correlations of these three channels with the rare decays K+ -> pi(+)nu(nu) over bar, K-L -> pi(0)nu(nu) over bar, B -> X(s)l(+)l(-) and B-s -> mu(+)mu(-) offer powerful tests of New Physics with new right-handed couplings and non-MFV interactions.

• 出版日期2009-4