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

We measured the B d→π 0π 0B d→π 0π 0 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→π 0π 0)|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 B d→π 0π 0B d→π 0π 0 puzzle.
 [1] ;  [1] ; ORCiD logo [2] ;  [3]
  1. Univ. of Chinese Academy of Sciences, Beijing (China); Chinese Academy of Sciences (CAS), Beijing (China)
  2. Chongqing Univ., Chongqing (China)
  3. SLAC National Accelerator Lab., Menlo Park, CA (United States); Stanford Univ., Stanford, CA (United States)
Publication Date:
Grant/Contract Number:
2015CB856703; 11275280; 11175249; 11375200; CDJZR305513; AC02-76SF00515
Published Article
Journal Name:
Physics Letters. Section B
Additional Journal Information:
Journal Volume: 748; Journal Issue: C; Journal ID: ISSN 0370-2693
Research Org:
SLAC National Accelerator Lab., Menlo Park, CA (United States)
Sponsoring Org:
USDOE Office of Science (SC)
Country of Publication:
United States
OSTI Identifier:
Alternate Identifier(s):
OSTI ID: 1236562