TY - JOUR
T1 - The anatomy of ε′ ε in the standard model
AU - Buchalla, Gerhard
AU - Buras, Andrzej J.
AU - Harlander, Michaela K.
N1 - Funding Information:
We would like to thank very much Pawel Krawczyk for participation at the early stage of this work, for extensive discussions concerning the initial values of the Wilson coefficient functions and for pointing out the existence of the operators Q~1 and Q~. We also thank Jean-Marc Gerard, George Hou, Markus Lautenbacher, Manfred Lindner and Peter Weisz for discussions and encouragement. This work has been supported in part by the German Bundesministerium für Forschung und Technologie under the contract 06TM761.
PY - 1990/6/18
Y1 - 1990/6/18
N2 - We perform a detailed renormalization group analysis of the ratio ε′ ε for 50 GeV < mt < 250 GeV including the contributions from the gluon penguin, photon penguin, Z0-penguin and neutral Higgs penguin diagrams as well as from π0-η-η′ mixing and current-current operators. The final result for the Wilson coefficient functions with full O(αQED) corrections taken into account can be written in a compact and transparent form. Using the constraints on mt and the phase δ coming from the data on ε and B0-B0 mixing, we investigate the dependence of the resulting ε′ ε ratio on the values of mt, ΛQCD, BK, ms(1 GeV), FB and the ratio Γ(b → u) Γ(b → c). The presence of Z0-diagrams suppresses strongly ε′ ε for large values of mt. For mt ≃ O(100 GeV) the standard model is milliweak wity typical values ε′ ε ≃ (1.0 ± 0.5) × 10-3. For mt ≃ O(220 GeV) it behaves like a superweak theory with | ε′ ε|≃0 and negative values for larger mt. These two distinct regions of mt, "milliweak" and "superweak" respectively, are the two regions of mt favoured by the data on ε{lunate} and B0-B0 mixing.
AB - We perform a detailed renormalization group analysis of the ratio ε′ ε for 50 GeV < mt < 250 GeV including the contributions from the gluon penguin, photon penguin, Z0-penguin and neutral Higgs penguin diagrams as well as from π0-η-η′ mixing and current-current operators. The final result for the Wilson coefficient functions with full O(αQED) corrections taken into account can be written in a compact and transparent form. Using the constraints on mt and the phase δ coming from the data on ε and B0-B0 mixing, we investigate the dependence of the resulting ε′ ε ratio on the values of mt, ΛQCD, BK, ms(1 GeV), FB and the ratio Γ(b → u) Γ(b → c). The presence of Z0-diagrams suppresses strongly ε′ ε for large values of mt. For mt ≃ O(100 GeV) the standard model is milliweak wity typical values ε′ ε ≃ (1.0 ± 0.5) × 10-3. For mt ≃ O(220 GeV) it behaves like a superweak theory with | ε′ ε|≃0 and negative values for larger mt. These two distinct regions of mt, "milliweak" and "superweak" respectively, are the two regions of mt favoured by the data on ε{lunate} and B0-B0 mixing.
UR - http://www.scopus.com/inward/record.url?scp=0000020377&partnerID=8YFLogxK
U2 - 10.1016/0550-3213(90)90275-I
DO - 10.1016/0550-3213(90)90275-I
M3 - Article
AN - SCOPUS:0000020377
SN - 0550-3213
VL - 337
SP - 313
EP - 362
JO - Nuclear Physics, Section B
JF - Nuclear Physics, Section B
IS - 2
ER -