Related papers: The Emergence of the $\Delta U=0$ Rule in Charm Ph…
CP violation in charm decay was observed in the decays $D^0\rightarrow P^{\pm}P^{\mp}$ of a $D^0$ meson to two pseudoscalars. When interpreted within the SM, the results imply that the ratio of the relevant rescattering amplitudes has a…
A model-independent analytical analysis for charmless B decays is presented. It is demonstrated that the CP-averaging branching ratio difference $\Delta R = R_c - R_n$ in $B\to \pi K$ decays with $R_c = 2Br(\pi^0K^-)/Br(\pi^-\bar{K}^0)$ and…
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^-) -…
The recent measurement of $\Delta A_{CP}$ by the LHCb collaboration requires an ${\cal O}(10)$ enhancement coming from hadronic physics in order to be explained within the SM. We examine to what extent can NP models explain $\Delta A_{CP}$…
Recent evidence for direct CP violation in non-leptonic charm decays cannot be easily accommodated within the Standard Model (SM). On the other hand, it fits well in new physics models generating CP violating Delta C=1 chromomagnetic dipole…
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…
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…
Recent LHCb data shows that the direct CP asymmetries of the decay modes $D^0\rightarrow \pi^+\pi^-$ and $D^0\rightarrow K^+K^-$ have the same sign, violating an improved $U$-spin limit sum rule in an unexpected way at $2.1\sigma$. From 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,…
We present a strategy designed to separate several possible origins of the well-known enhancement of the Delta{I}=1/2 amplitude in non-leptonic kaon decays. In particular, we seek to disentangle the contribution of physics at the typical…
We study the dependence on the charm quark mass of the leading-order low-energy constants of the $\Delta S=1$ effective Hamiltonian, with the aim of elucidating the role of the charm mass scale in the $\Delta I=1/2$ rule for $K\to\pi\pi$…
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…
Very recently, the LHCb Collaboration observed the $CP$ violation (CPV) in the charm sector for the first time, with $\Delta A_{CP}^{\rm dir}\equiv A_{CP}(D^0\to K^+K^-)-A_{CP}(D^0\to \pi^+\pi^-)=(-1.54\pm0.29)\times10^{-3}$. This result is…
In this talk we briefly present a flavor-SU(3) technique to study branching ratios and direct CP asymmetries $D$-meson decays. The first part of the talk is meant to set up a foundation, based on previous work, to deal with flavor-SU(3)…
Direct CP violation in the hadronic charm decays provides a good testing ground for the Kobayashi-Maskawa mechanism in the Standard Model. Any significant deviations from the expectation would be indirect evidence of physics beyond the…
The discovery of CP violation in charm sector in 2019 was a milestone in searches performed over last decades. The $\Delta A_{CP}$ measured by LHCb is at the upper end of the Standard Model predictions. This triggers many interpretations…
We find new sum rules between direct CP asymmetries in $D$ meson decays with coefficients that can be determined from a global fit to branching ratio data. Our sum rules eliminate the penguin topologies $P$ and $PA$, which cannot be…
Motivated by the recent observation of CP violation in the charm sector by LHCb, we study direct CP asymmetries in the standard model (SM) for the singly Cabibbo-suppressed two-body hadronic decays of charmed mesons using the…
Motivated by the very important discovery of CP violation in charm-decays for the first time, by the LHCb collaboration, the role of nearby resonances such as the scalar $f_0(1710)$ in accounting for the observed CP is discussed. It is…
We present updated results of an SU(3)-flavor analysis of D->P P decay data including linear breaking and no further assumptions. The global fit is consistent with nominal (~ 30%) SU(3)F breaking and returns enhanced penguin (triplet)…