Measurements of CP Violation in $B^0\to D^{\ast -}{\pi }^{+}$ and $B^0\to D^{-}{\pi }^{+}$ Decays

Abstract

We report measurements of time dependent decay rates for $B^0\to D^{(\ast )-}{\pi }^{+}$ decays and extraction of CP violation parameters that depend on ${\varphi }_3$. Using fully reconstructed $D^{(\ast )}\pi$ events and partially reconstructed $D^{\ast }\pi$ events from a data sample that contains 386 million $B\bar{B}$ pairs that was collected near the ${\rm Y}(4S)$ resonance, with the Belle detector at the KEKB asymmetric energy $e^{+}{e}^{-}$ collider, we obtain the CP violation parameters $S^{+}(D^{(\ast )}\pi )$ and $S^{-}(D^{(\ast )}\pi )$. We obtain $S^{+}(D^{\ast }\pi )=0.049\pm 0.020(\mathrm{stat})\pm 0.011(\mathrm{sys})$, $S^{-}(D^{\ast }\pi )=0.031\pm 0.019(\mathrm{stat})\pm 0.011(\mathrm{sys})$, and $S^{+}(D\pi )=0.031\pm 0.030(\mathrm{stat})\pm 0.012(\mathrm{sys})$, $S^{-}(D\pi )=0.068\pm 0.029(\mathrm{stat})\pm 0.012(\mathrm{sys})$. These results are an indication of CP violation in $B^0\to D^{\ast -}{\pi }^{+}$ and $B^0\to D^{-}{\pi }^{+}$ decays at the $2.5\sigma$ and $2.2\sigma$ levels, respectively. If we use the values of $R_{D^{(\ast )}\pi }$ that are derived using assumptions of factorization and SU(3) symmetry, the branching fraction measurements for the $D_s^{(\ast )}\pi$ modes, and lattice QCD calculations, we can restrict the allowed region of $|\sin (2{\varphi }_1+{\varphi }_3)|$ to be above 0.44 and 0.52 at 68% confidence level from the $D^{\ast }\pi$ and $D\pi$ modes, respectively.

arXiv comment14 pages, 12 figures, submitted to Physical Review D

References in corpus (19)

• Big Bang Nucleosynthesis (in "The Review of Particle Properties" 2004)
• Study of B- => D**0 pi-(D**0 => D(*)+ pi-) decays
• Impact of tag-side interference on time-dependent CP asymmetry measurements using coherent B0 B0bar pairs
• New Strategies to Obtain Insights into CP Violation Through $B_s\to D_s^{\pm }{K}^{\mp },D_s^{\ast \pm }{K}^{\mp },...$ and $B_d\to D^{\pm }{\pi }^{\mp },D^{\ast \pm }{\pi }^{\mp },...$ Decays
• Improved Measurement of CP-Violation Parameters sin(2phi1) and |lambda|, B Meson Lifetimes, and B0-B0bar Mixing Parameter Delta m_d
• Clean CKM Information from Bd(t) -> D(*)+/- pi-/+
• Decay Constants of B and D Mesons from Non-perturbatively Improved Lattice QCD
• Observation of Mixing-induced CP Violation in the Neutral B Meson System
• Proper-time Resolution Function for Measurement of Time Evolution of B Mesons at the KEK B-Factory
• Determination of the angle gamma using B -> D* V modes
• Extracting Weak Phase Information from B -> V_1 V_2 Decays
• Observation of Ds+ K- and evidence for Ds+ pi- final states in neutral B decays
• Measurement of Time-Dependent CP-Violating Asymmetries and Constraints on sin(2 beta+gamma) with Partial Reconstruction of B->D*-+pi+- Decays
• A Study of the Rare Decays $B^0\to D_s^{(\ast )+}{\pi }^{-}$ and $B^0\to D_s^{(\ast )-}{K}^{+}$
• Precise Measurement of B Meson Lifetimes with Hadronic Decay Final States
• Extraction of a Weak Phase from $B\to D^{(\ast )}\pi$
• Measurement of Time-Dependent CP Asymmetries and Constraints on sin(2beta+gamma) with Partial Reconstruction of B0 -> D*-+ pi+- Decays
• Measurement of the $B^0-{\bar{B}}^0$ mixing rate with $B^0({\bar{B}}^0)\to D^{\ast \mp }{\pi }^{\pm }$ partial reconstruction
• Time-Dependent CP Violation Effects in Partially Reconstructed $B^0\to D^{\ast }\pi$ Decays

Cited by in corpus (15)

• Averages of $b$-hadron, $c$-hadron, and $\tau$-lepton properties as of summer 2016
• Averages of $b$-hadron, $c$-hadron, and $\tau$-lepton properties as of 2018
• Averages of $b$-hadron, $c$-hadron, and $\tau$-lepton properties as of 2021
• Implications of LHCb measurements and future prospects
• Flavor Physics in the Quark Sector
• B, D and K decays
• Scalar-mediated $t\bar{t}$ forward-backward asymmetry
• Exploring $B_s\to D_s^{(\ast )\pm }{K}^{\mp }$ Decays in the Presence of a Sizable Width Difference $\Delta {\Gamma }_s$
• Search for Time-Dependent CPT Violation in Hadronic and Semileptonic B Decays
• CP violation in the B system
• Measurement of CP asymmetry in $B_s^0\to D_s^{\mp }{K}^{\pm }$ decays
• Measurements of time-dependent CP asymmetries in $B\to D^{\ast \mp }{\pi }^{\pm }$ decays using a partial reconstruction technique
• Measurements of Branching Fractions for B0 --> Ds+pi- and B0-bar --> Ds+K-
• Search for B+ -> D*+ pi0 decay
• Experimental Status of the CKM Matrix