English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Tools annual

Global: Zendy Free Plan

Global: Zendy Tools monthly

Global: Zendy Plus monthly

CP-violating asymmetries in the decay B 0 (t) → π + π − are a potentially rich source of information about both strong and weak phases. In a previous treatment by the present authors use was made of an assumption about the relative magnitude of tree and penguin amplitudes contributing to this process. This assumption involved an ambiguity in relating the tree amplitude to the amplitude for B → πℓν. It is shown here that one can avoid this assumption, which adopted a particular convention for tree and penguin amplitudes, and that the results are convention-independent. The study of CP-violating asymmetries in the decays B 0 (t) → π + π − has reached an interesting stage. Two collaborations working at asymmetric B factories, the Babar Collaboration at PEP-II (Stanford) [1] and the Belle Collaboration at KEK-B (Tsukuba, Japan) [2] have both reported measurements of time-dependent asymmetries in this process and its charge-conjugate which are potentially rich sources of information of both strong and weak phases. The weak phases are those of elements in the Cabibbo-Kobayashi-Maskawa (CKM) matrix describing the weak charge-changing couplings of quarks. At present these phases provide a satisfactory description of all observed CP-violating phenomena in both K and B decays. In a previous article [3] (for a more complete discussion, see also [4]), we analyzed these CP-violating asymmetries using assumptions which included knowledge of the ratio of tree and penguin amplitudes [5, 6]. This knowledge was obtained from other processes using the factorization hypothesis. However, the nature of the tree amplitude and the value of the above ratio depended on our convention for defining the tree and penguin amplitudes, leading to some indeterminacy in the result. Certain aspects of ambiguities following from the penguin amplitude convention were discussed earlier in [7, 8, 9], and recently in [10].

Convention-independent study of CP-violating asymmetries in $B \to \pi \pi$