1 / 8

The rare decay in the Standard Model

The rare decay in the Standard Model. Da f ne 04, June 2004. Christopher Smith Laboratori Nazionali di Frascati. G. Isidori, R. Unterdorfer, C.S., hep-ph/0404127. In K pp , CP-violation is small e 10 - 3 , and direct CPV even smaller e ’ /e 10 - 3 .

april
Download Presentation

The rare decay in the Standard Model

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. The rare decay in the Standard Model Dafne 04, June 2004 Christopher Smith Laboratori Nazionali di Frascati G. Isidori, R. Unterdorfer, C.S., hep-ph/0404127

  2. In Kpp, CP-violation is small e 10-3, and direct CPV even smaller e’/e 10-3. In contrast, direct CP-violation is expected to be dominant (or at least sizeable) in . Introduction Large direct CP-violation Small theoretical uncertainties Hadronic uncertainties plague the theoretical analysis of e’/e. In contrast, are semi-leptonic processes and the direct-CPV contribution can be computed with high accuracy. Indeed, the hadronic matrix element can be obtained from .

  3. Theoretical Structure Direct CP-violation Indirect CP-violation CP-conserving Long-distance Chiral Perturbation Th. (KL-KS mixing) Long-distance ChPT, VMD, ... Short-distance Operator Product Exp. (large Z, W, t mass) Final State 0++: (Final State 2++: ) The only piece for ~ ~ ~ ~

  4. Outline of the computation The leading order is obtained from the charged pion loop e+e- : helicity suppressed m+m- : leading CPC (0++) Equivalently, we can compute Provided is a function of T² only.

  5. Standard Model Predictions I • with and . • with counterterm . • theoretical errors of 10% or less on all CPV coefficients. • conservative error estimate of 30% for the CPC term. Bounds on Imlt Current experimental bounds from KTeV imply:

  6. Standard Model Predictions II Branching Ratios Constructivenow favored by two independent analyses* Destructive * G. Buchalla, G. D’Ambrosio, G. Isidori, Nucl.Phys.B672,387 (2003) S. Friot, D. Greynat, E. de Rafael, hep-ph/0404136

  7. Sensitivity to New Physics Ratios of B Kp modes could be explained by enhanced electroweak penguin contributions*. Those processes would then affect the Wilson coefficients: and enhance the BR’s: * A. J. Buras, R. Fleischer, S. Recksiegel, F. Schwab, hep-ph/0402112

  8. Prospects The set of decays , and - very clean theoretically, - is extremely well suited to test the SM, - very sensitive to New Physics signal, - non-trivial information on the nature of New Physics. On the experimental side, we would need : Required experimental sensitivity expected soon. : The main uncertainty in the CPV comes from aS. : Both rate (for CPC-0++) and spectrum (for CPC-2++).

More Related