Related papers: Direct CP violation in D-meson decays
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…
A long-standing puzzle in charm physics is the large difference between the D0 -> K+ K- and D0 -> pi+ pi- decay rates. Recently, the LHCb and CDF collaborations reported a surprisingly large difference between the direct CP asymmetries,…
LHCb, CDF and most recently Belle have observed a large difference between direct CP asymmetries in $D^0\to K^+K^-$ and $D^0\to\pi^+\pi^-$. We use the measured value of $\Delta A_{CP}$ to constrain the magnitude and strong phase of a…
Direct CP violation in two-body $D\to PP$ and $D\to V\!P$ decays is studied within the framework of the topological amplitude approach for tree amplitudes and the QCD factorization approach for penguin amplitudes. It is the interference…
We investigate the possibility of observing the direct CP violation in the decay modes $B^- \to D^0 D_s^-$ and $D^0 D^-$ within the Standard Model. Including the contributions arising from the tree, annihilation, QCD as well as electroweak…
We point out that, if the direct CP asymmetries in the $D \to \pi^+ \pi^-$ and $D \to K^+ K^-$ decays are unequal, the indirect CP asymmetries as measured in these modes are necessarily unequal. This nonuniversality of indirect CP…
In view of the recent LHCb measurement of Delta A_CP, the difference between the time-integrated CP asymmetries in D --> K+K- and D --> pi+pi- decays, we perform a comparative study of the possible impact of New Physics degrees of freedom…
The LHCb and CDF Collaborations have recently reported evidence for a CP asymmetry around -0.7% in $\Delta A_{CP}$, the difference between $A_{CP}(D^0 \to K^+ K^-)$ and $A_{CP}(D^0 \to \pi^+\pi^-)$. In the Standard Model this effect may be…
In this paper we investigate CP violation in charged decays of $D$ meson. Particularly, we study the direct CP asymmetry of the Cabibbo favored non-leptonic $D^+ \rightarrow \bar K^0 \pi^+$ and the doubly Cabibbo-suppressed decay mode $D^+…
This talk addresses two topics related to CP asymmetries in $D$ meson decays to two pseudoscalar mesons. First I discuss how new physics can be distinguished from the Standard Model through two sum rules relating three direct CP asymmetries…
A search for direct CP violation in D0 -> h- h+ (where h=K or pi) is presented using data corresponding to an integrated luminosity of 1.0 fb^-1 collected in 2011 by LHCb in pp collisions at a centre-of-mass energy of 7 TeV. The analysis…
I discuss hadronic decays of $D$ mesons with emphasis on the recent discovery of charm CP violation in $D^0\to K^+K^-,\pi^+\pi^-$ decays. The measured difference $\Delta a_{CP} \, \equiv \; a_{CP}^{\mathrm{dir}}(D^0\rightarrow K^+K^-) -…
Evidence of CP violation in the charm sector has been observed recently by the LHCb and CDF Collaborations. The issue of whether it can be accommodated within the standard model (SM) is examined in this talk. We conclude that the CP…
We investigate to what extent the recently measured value for a non-vanishing direct CP asymmetry in D0 -> K+ K- and D0 -> pi+ pi- decays can be accommodated in the Standard Model (SM) or extensions with a constrained flavour sector, for…
The first experimental evidence for direct CP violation in charm-quark decays has recently been presented by the LHCb collaboration in the difference between the D -> K+ K- and D -> pi+ pi- time-integrated CP asymmetries. We estimate the…
We report updated measurements of indirect and direct CP asymmetry in decays $D^0 \to K^+K^-,\pi^+\pi^-$ and a new measurement of direct and indirect CP asymmetry in decays $D^0 \to \pi^0\pi^0$, using the full data sample of the Belle…
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…
Direct CP violation in B^0-> K^+\pi^- decay has emerged at -10% level, but the asymmetry in B^+ -> K^+\pi^0 mode is consistent with zero. This difference points towards possible New Physics in the electroweak penguin operator. We point out…
Indirect and direct CP violations have been established in K_L and B_d decays. They have been found in two-body decay channels -- with the exception of K_L to pi^+ pi^- e^+ e^- transitions. Evidence for direct CP asymmetry has just appeared…
We study the direct CP violation effect in the decay mode $B^+ \to \phi K^+$. This decay mode is dominated by the loop induced $\bar b \to \bar s s \bar s$ penguin diagram with a tiny contribution from annihilation diagram. Therefore, the…