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Related papers: A $U$-Spin Anomaly in Charm CP Violation

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A difference of several tenths of a percent has been observed between the direct CP asymmetries of $D^0\to K^+K^-$ and $D^0\to \pi^+\pi^-$. It has been noted recently that CP asymmetries in such singly-Cabibbo-suppressed (SCS) decays can…

High Energy Physics - Phenomenology · Physics 2013-04-10 Bhubanjyoti Bhattacharya , David London , Michael Gronau , Jonathan L. Rosner

We consider CP violating effects in decays of the type $B^\pm\to \gamma a^\pm_{1,2}$ where $a_{1,2}$ are the $J^P=1^+$ and $2^+$ resonances each decaying to the common final state via $a^\pm_{1,2} \to\pi^\pm\rho^0$. The resonances enhance…

High Energy Physics - Phenomenology · Physics 2010-11-01 D. Atwood , A. Soni

Direct CP violation can occur in B-meson decays of the type b -> d+c+cbar, where the charm-anticharm pair forms a J/psi. The CP asymmetry requires the contribution to the amplitude from decays into other states, which rescatter into d+J/psi…

High Energy Physics - Phenomenology · Physics 2010-11-01 Joao M. Soares

Basic idea of $CP$ violation and its importance for cosmology, Standard Model and possible New Physics are introduced. Recent (2019) discovery of CP violation in charm in the $\Delta A_{CP}$ between $D^0\rightarrow K^-K^+$ and…

High Energy Physics - Experiment · Physics 2024-07-09 Aleksei Chernov

We have searched for CP-violating asymmetries in neutral charm meson decays in 13.7 fb^-1 of e^+e^- collision data at sqrt{s} = 10.6 GeV with the CLEO detector. The measured asymmetries in the rate of D0 and D0bar decays to K0sPi0, Pi0Pi0…

High Energy Physics - Experiment · Physics 2010-04-08 G. Bonvicini , CLEO Collaboration

We present standard model (SM) estimates for exclusive $c \to u \gamma$ processes in heavy quark and hybrid frameworks. Measured branching ratios ${\cal{B}}(D^0 \to (\phi, \bar K^{*0}) \gamma)$ are at or somewhat exceeding the upper range…

High Energy Physics - Phenomenology · Physics 2018-10-01 Stefan de Boer , Gudrun Hiller

I discuss the measurement of CP-violating asymmetries ($A_{\Gamma}$) between effective lifetimes of $D^0$ or $\bar{D}^0$ mesons. Fully reconstructed $D^0\to K^+ K^-$ and $D^0\to \pi^+\pi^-$ decays collected in $p\bar{p}$ collisions by the…

High Energy Physics - Experiment · Physics 2015-08-31 Sabato Leo

Recently, LHCb experiment announced a 3.5$\sigma$ evidence for direct CP violation in $D^0$ decay by looking at the difference between $A_{CP}(D^0\rightarrow K^+K^-)$ and $A_{CP}(D^0\rightarrow \pi^+\pi^-)$. This is the first evidence of CP…

High Energy Physics - Experiment · Physics 2012-02-20 Hai-Bo Li , SHi-Hai Zhu

The recent observation of B^0_d->\pi^0\pi^0 and \bar{B}^0_d->\pi^0\pi^0 decay modes allows us to make a fresh isospin analysis of B->\pi\pi transitions. We find that current experimental data can impose some model-independent constraints on…

High Energy Physics - Phenomenology · Physics 2014-11-17 Zhi-zhong Xing

We present the current status of experimental results and prospects for the determination of CP and T violation in the charm sector. Such measurements have acquired renewed interest in recent years in view of theoretical work, which has…

High Energy Physics - Experiment · Physics 2011-06-15 Giampiero Mancinelli

We comment on the implications of the recently measured CP asymmetry in B --> Phi K_S decay. The data disfavor the Standard Model at 2.7 sigma and -if the trend persists in the future with higher statistics - require the existence of CP…

High Energy Physics - Phenomenology · Physics 2009-11-07 Gudrun Hiller

Several years ago, it was pointed out that the U-spin-related decays $B_d\to\pi^+\pi^-$, $B_s\to K^+K^-$ and $B_d\to\pi^\mp K^\pm$, $B_s\to \pi^\pm K^\mp$ offer interesting strategies for the extraction of the angle gamma of the unitarity…

High Energy Physics - Phenomenology · Physics 2008-11-26 Robert Fleischer

In this proceeding, I discuss results from the BaBar and Belle collaborations for searches of direct CP violation in the singly Cabibbo-suppressed decay $\D^\pm\to K^+K^-\pi^\pm$ from $e^+e^-$ annihilation data collected at a center-of-mass…

High Energy Physics - Experiment · Physics 2019-08-14 Ryan Mackenzie White

Motivated by recent LHCb measurements of CP violation in $\Lambda_b$ three-body decays, we conduct an analysis of CP asymmetry in three-body decays of bottom baryons utilizing U-spin symmetry. We first develop a convenient representation…

High Energy Physics - Phenomenology · Physics 2024-11-28 Wei Wang , Zhi-Peng Xing , Zhen-Xing Zhao

We present charm CP violation and mixing measurements at Belle. They are the first observation of $D^0-\bar{D}^0$ mixing in $e^+e^-$ collisions from $D^0\rightarrow K^+\pi^-$ decays, the most precise mixing and indirect CP violation…

High Energy Physics - Experiment · Physics 2019-08-13 B. R. Ko

Motivated by the $3.8\sigma$ deviation from no CP violation hypothesis for the CP asymmetry (CPA) difference between $D^0\to K^+ K^-$ and $D^0\to \pi^+ \pi^-$, reported recently by LHCb and CDF, we investigate the CP violating effect due to…

High Energy Physics - Phenomenology · Physics 2015-06-05 Chuan-Hung Chen , Chao-Qiang Geng , Wei Wang

We present preliminary results of improved measurements of the CP-violating asymmetries and branching fractions in the decays B0 -> pi+ pi-, B0 -> K+ pi-, B0 -> pi0 pi0, and B0 -> K0 pi0. This update includes all data taken at the Y(4S)…

High Energy Physics - Experiment · Physics 2008-07-31 The BABAR Collaboration , B. Aubert

CP asymmetries in B_d \to D^+D^-, D^{*+}D^-, D^+D^{*-} and D^{*+}D^{*-} decays are investigated with the help of the factorization approximation and isospin relations. We find that the direct CP violation is governed only by the…

High Energy Physics - Phenomenology · Physics 2009-10-31 Zhi-zhong Xing

A recent combination of measurements performed by the LHCb collaboration determined that $\gamma=(63.8^{+3.5}_{-3.7})^\circ$. The fit combined the results of $\gamma$ and charm measurements, which resulted in precision improvements for the…

High Energy Physics - Experiment · Physics 2024-04-30 Innes Mackay

We devise tests for a new physics origin of the recently measured direct CP violation in singly Cabibbo suppressed D decays. The tests take the form of sum rules for the CP asymmetries in various D decays. They are based on the fact that…

High Energy Physics - Phenomenology · Physics 2015-06-04 Yuval Grossman , Alexander L. Kagan , Jure Zupan