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

200 papers

Although CP violation is predicted to be small in the Standard Model, there exists a continuing theoretical interest within the charm sector due to enhancements of CPV through new physics processes. We present an overview of the…

High Energy Physics - Experiment · Physics 2013-01-22 Eric White

The LHCb and CDF collaborations reported a surprisingly large difference between the direct CP asymmetries, Delta A_CP, in the D0 -> K+ K- and D0 -> pi+ pi- decay modes. We show that this measurement can be plausibly explained within the…

High Energy Physics - Phenomenology · Physics 2013-02-15 Joachim Brod

The observation of $CP$ violation in the difference of $CP$ asymmetries between $D\to K^+K^-$ and $D\to \pi^+\pi^-$ has raised a debate whether the observed asymmetries can be regarded as a signal of physics beyond the standard model (SM).…

High Energy Physics - Phenomenology · Physics 2026-05-08 Rahul Sinha , Thomas E. Browder , N. G. Deshpande , Dibyakrupa Sahoo , Nita Sinha

Since the standard model contribution is virtually absent, any observation of direct CP violation in the Cabibbo-favored charmed meson decays would be evidence of new physics. In this paper, we conduct a quantitative study on direct CP…

High Energy Physics - Phenomenology · Physics 2018-11-14 Naoyuki Haba , Hiroyuki Umeeda , Toshifumi Yamada

A U-spin relation among four ratios of amplitudes for $D^0 \to \pi^+K^-$, $K^+\pi^-$, $K^+K^-, \pi^+\pi^-$, including first, second and third order U-spin breaking, has been derived recently with a precision of $10^{-3}$. We study effects…

High Energy Physics - Phenomenology · Physics 2014-09-24 Mchael Gronau

We propose for the first time a method to perform analysis of time-dependent CP asymmetries in charm by using both, correlated and un-correlated $D^0$ mesons. Here we consider the decay channels $D^0\to K^+ K^-$ and $D^0\to \pi^+ \pi^-$.…

High Energy Physics - Phenomenology · Physics 2011-09-22 Gianluca Inguglia

We point out that the CP asymmetries in the decays $D^0\rightarrow K_{S} K^{*0}$ and $D^0\rightarrow K_{S} \overline{K}{}^{*0}$ are potential discovery channels for charm CP violation in the Standard Model. We stress that no flavor tagging…

High Energy Physics - Phenomenology · Physics 2017-12-27 Ulrich Nierste , Stefan Schacht

This work presents the first detailed numerical predictions of CP violation in antitriplet charmed baryon decays. Adopting the flavor $SU(3)_F$ symmetry and the final state re-scattering framework, we relate the CKM-suppressed amplitudes to…

High Energy Physics - Phenomenology · Physics 2025-06-24 Xiao-Gang He , Chia-Wei Liu

We impose U spin symmetry ($SU(2)_{\rm Uspin}$) on the Hamiltonian for $B$ decays. As expected, we find the equality of amplitudes related by the exchange $d \leftrightarrow s$. We also find that the amplitudes for the $\Delta S=0$…

High Energy Physics - Phenomenology · Physics 2023-01-31 Bhubanjyoti Bhattacharya , Suman Kumbhakar , David London , Nicolas Payot

According to the standard model, the Cabibbo-favored (CF) decays are $CP$ conserve at tree level. Observation of any finite $CP$ asymmetry can be received as a signal of new physics. In CF charm meson decays, $ D^0 \rightarrow K^- \pi^+ $…

High Energy Physics - Phenomenology · Physics 2018-11-16 Mohammadmahdi Ettefaghi , Reza Moazzemi , Mohsen Rousta

We perform a comprehensive SU(3)-flavor analysis of charmed mesons decaying to two pseudoscalar SU(3)-octet mesons. Taking into account SU(3)-breaking effects induced by the splitting of the quark masses, m_s != m_{u,d}, we find that…

High Energy Physics - Phenomenology · Physics 2013-05-30 Gudrun Hiller , Martin Jung , Stefan Schacht

We present a general analysis on charmless B-meson decays $B\to \pi\pi$ and $\pi K$. It is noticed that the final state interactions and inelastic rescattering effects must be significant in order to understand the consistency of the…

High Energy Physics - Phenomenology · Physics 2014-11-17 Y. F. Zhou , Y. L. Wu , J. N. Ng , C. Q. Geng

The non-leptonic $D^0\to K^- K^+$ and $D^0\to \pi^-\pi^+$ decays are powerful probes of the Standard Model and are related to each other through the $U$-spin symmetry of the strong interaction. Using lattice QCD inputs we calculate the…

High Energy Physics - Phenomenology · Physics 2025-12-12 Robert Fleischer , Maria Laura Piscopo , K. Keri Vos , B. Yağmur Zubaroğlu

Using updated measurements and SU(3)-breaking form factors, we have a detailed look at the B_d -> pi^+ pi^-, B_s -> K^+ K^- and B_d -> pi^\mp K^\pm, B_s -> pi^\pm K^\mp systems. The corresponding decays are related to each other by the…

High Energy Physics - Phenomenology · Physics 2015-03-17 Robert Fleischer , Robert Knegjens

The LHCb Collaboration has recently reported evidence for a CP asymmetry approaching the percent level in the difference between $D^0 \to \pi^+ \pi^-$ and $D^0 \to K^+ K^-$. We analyze this effect as if it is due to a penguin amplitude with…

High Energy Physics - Phenomenology · Physics 2013-05-30 Bhubanjyoti Bhattacharya , Michael Gronau , Jonathan L. Rosner

Direct CP violation beyond the standard model can be produced in charged D decays to final states with a $K_S$ by small new physics contributions to the transitions $D^+ \to K^o X^+$, where $X^+$ denotes any positively charged hadronic…

High Energy Physics - Phenomenology · Physics 2007-05-23 Harry J. Lipkin

We have searched for CP violation of charmed mesons in the decays $D\to K^0_S P$, where $D$ denotes $D^0$ and $D^+_{(s)}$, and $P$ denotes the pseudo-scalar mesons $\pi^+$, $K^+$, $\pi^0$, $\eta$, and $\eta'$. No evidence of CP violation in…

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

The recently measured direct CP asymmetries in the processes $D^0\to \pi^+\pi^-$ and $D^0\to K^+K^-$ show a significant deviation from the naive Standard Model expectation. Using a general parameterization of the decay amplitudes, we show…

High Energy Physics - Phenomenology · Physics 2015-06-04 Enrico Franco , Satoshi Mishima , Luca Silvestrini

We present flavor SU(3) sum rules for $D \to PP$ and $D \to PV$ decay amplitudes, that are valid to second order in symmetry breaking by the strange quark mass spurion. Decay rate sum rules are also computed to this order. Particular…

High Energy Physics - Phenomenology · Physics 2015-06-12 Yuval Grossman , Dean J Robinson

CP violation in the charm sector is highly sensitive to new physics due to its small predicted value within the standard model. By this work, we investigated the CP violation in the cascade decay process $D^0(t_1) \to \pi^0 K(t_2) \to…

High Energy Physics - Phenomenology · Physics 2025-03-19 Wen-Jie Song , Shi-Qi Wang , Qin Qin , Ya Li