Details

Autor(en) / Beteiligte

• Qiao, Cong-Feng
• Zhu, Rui-Lin
• Wu, Xing-Gang
• Brodsky, Stanley J.

Titel

A possible solution to the B → π π puzzle using the principle of maximum conformality

Ist Teil von

• Physics letters. B, 2015-09, Vol.748 (C), p.422-427

Ort / Verlag

Netherlands: Elsevier

Erscheinungsjahr

2015

Quelle

Alma/SFX Local Collection

Beschreibungen/Notizen

• We measured the Bd→π0π0Bd→π0π0 branching fraction and found that it deviates significantly from conventional QCD predictions, a puzzle which has persisted for more than 10 years. This may be a hint of new physics beyond the Standard Model; however, as we shall show in this paper, the pQCD prediction is highly sensitive to the choice of the renormalization scales which enter the decay amplitude. In the present paper, we show that the renormalization scale uncertainties for B→ππB→ππ can be greatly reduced by applying the Principle of Maximum Conformality (PMC), and more precise predictions for CP-averaged branching ratios B(B→ππ)B(B→ππ) can be achieved. Combining the errors in quadrature, we obtain View the MathML sourceB(Bd→π0π0)|PMC=(0.98-0.31+0.44)×10-6 by using the light-front holographic low-energy model for the running coupling. All of the CP-averaged B→ππB→ππ branching fractions predicted by the PMC are consistent with the Particle Data Group average values and the recent Belle data. Moreover, the PMC provides a possible solution for the Bd→π0π0Bd→π0π0 puzzle.