Branching Ratios and CP Asymmetries of B \to a_1(1260) πand a_1(1260) K Decays
| dc.creator | Yang, Kwei-Chou | |
| dc.date | 2007-05-28 | |
| dc.date | 2007-09-23 | |
| dc.date.accessioned | 2026-07-07T10:55:53Z | |
| dc.date.available | 2026-07-07T10:55:53Z | |
| dc.description | We present the studies of the decays $B\to a_1(1260) π$ and $a_1(1260) K$ within the framework of QCD factorization. Due to the G-parity, unlike the vector meson, the chiral-odd two-parton light-cone distribution amplitudes of the $a_1$ are antisymmetric under the exchange of quark and anti-quark momentum fractions in the SU(2) limit. The branching ratios for $a_1 π$ modes are sensitive to tree--penguin interference. The resultant ${\cal B}(B^0 \to a_1^\pm π^\mp)$ are in good agreement with the data. However, using the current Cabibbo--Kobayashi--Maskawa angles, $β=22.0^\circ$ and $γ=59.0^\circ$, our results for the mixing-induced parameter $S$ and $α_{\rm eff}$ differ from the measurements of the time-dependent CP asymmetries in the decay $B^0\to a_1^\pm π^\mp$ at about the $3.7σ$ level. This puzzle may be resolved by using a larger $γ\gtrsim 80^\circ$. For $a_1 K$ modes, the annihilation topologies give sizable contributions and are sensitive to the first Gegenbauer moment of the leading-twist tensor (chiral-odd) distribution amplitude of the $a_1$ meson. The $B\to a_1 K$ amplitudes resemble the corresponding $B\to πK$ ones very much. Taking the ratios of corresponding CP-averaged $a_1 K$ and $πK$ branching ratios, we can extract information relevant to the electroweak penguins and annihilations. The existence of new-physics in the electroweak penguin sector and final state interactions during decays can thus be explored. | |
| dc.description | 20 pages, 1 figure, 4 tables, typos corrected, some discussions added, version to appear in PRD | |
| dc.identifier | https://arxiv.org/abs/0705.4029 | |
| dc.identifier | http://arxiv.org/abs/0705.4029 | |
| dc.identifier | Phys.Rev.D76:094002,2007 | |
| dc.identifier | doi:10.1103/PhysRevD.76.094002 | |
| dc.identifier.uri | http://salesiana.dossiersoluciones.com/handle/123456789/186229 | |
| dc.subject | High Energy Physics - Phenomenology | |
| dc.subject | High Energy Physics - Experiment | |
| dc.title | Branching Ratios and CP Asymmetries of B \to a_1(1260) πand a_1(1260) K Decays | |
| dc.type | text |