Long-Distance dominance of the CP asymmetry in B̄→X s,d γ decays

Michael Benzke, Seung Joon Lee, Matthias Neubert, Gil Paz

Research output: Contribution to journalArticle

62 Citations (Scopus)

Abstract

We show that in the standard model the parametrically leading (by a factor 1/α s ) contribution to the inclusive CP asymmetry in B̄→X s,d γ decays arises from a long-distance effect in the interference of the electromagnetic dipole amplitude with the amplitude for an up-quark penguin transition accompanied by soft gluon emission. Using model estimates for the associated hadronic parameter Λ17u, we predict a value in the range -0.6%<AX s γSM<2.8%. In view of current experimental data, a future precision measurement of the flavor-averaged CP asymmetry would signal the presence of new physics only if a value below -2% was found. A cleaner probe of new physics is offered by the difference of the CP asymmetries in charged versus neutral B̄→X s γ decays.

Original languageEnglish
Article number141801
JournalPhysical Review Letters
Volume106
Issue number14
DOIs
Publication statusPublished - 2011 Apr 4
Externally publishedYes

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asymmetry
decay
cleaners
physics
quarks
electromagnetism
dipoles
interference
probes
estimates

ASJC Scopus subject areas

  • Physics and Astronomy(all)

Cite this

Long-Distance dominance of the CP asymmetry in B̄→X s,d γ decays . / Benzke, Michael; Lee, Seung Joon; Neubert, Matthias; Paz, Gil.

In: Physical Review Letters, Vol. 106, No. 14, 141801, 04.04.2011.

Research output: Contribution to journalArticle

Benzke, Michael ; Lee, Seung Joon ; Neubert, Matthias ; Paz, Gil. / Long-Distance dominance of the CP asymmetry in B̄→X s,d γ decays In: Physical Review Letters. 2011 ; Vol. 106, No. 14.
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