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 High Energy Physics - Phenomenology , 2007, DOI: 10.1103/PhysRevD.75.114006 Abstract: The noteworthy BaBar and Belle evidence for $D^0$-$\bar{D}^0$ mixing motivates us to study its impact on $D^0\to K^{*\pm} K^\mp$ decays and their CP-conjugate processes. We show that both the $D^0$-$\bar{D}^0$ mixing parameters ($x$ and $y$) and the strong phase difference between $\bar{D}^0\to K^{*\pm}K^\mp$ and $D^0\to K^{*\pm}K^\mp$ transitions ($\delta$) can be determined or constrained from the time-dependent measurements of these decay modes. On the $\psi (3770)$ and $\psi (4140)$ resonances at a $\tau$-charm factory, it is even possible to determine or constrain $x$, $y$ and $\delta$ from the time-independent measurements of coherent $(D^0\bar{D}^0) \to (K^{*\pm} K^\mp)(K^{*\pm} K^\mp)$ decays. If the CP-violating phase of $D^0$-$\bar{D}^0$ mixing is significant in a scenario beyond the standard model, it can also be extracted from the $K^{*\pm} K^\mp$ events.
 Physics , 2007, DOI: 10.1103/PhysRevD.75.114006 Abstract: The noteworthy BaBar and Belle evidence for $D^0$-$\bar{D}^0$ mixing motivates us to study its impact on $D^0\to K^{*\pm} K^\mp$ decays and their CP-conjugate processes. We show that both the $D^0$-$\bar{D}^0$ mixing parameters ($x$ and $y$) and the strong phase difference between $\bar{D}^0\to K^{*\pm}K^\mp$ and $D^0\to K^{*\pm}K^\mp$ transitions ($\delta$) can be determined or constrained from the time-dependent measurements of these decay modes. On the $\psi (3770)$ and $\psi (4140)$ resonances at a $\tau$-charm factory, it is even possible to determine or constrain $x$, $y$ and $\delta$ from the time-independent measurements of coherent $(D^0\bar{D}^0) \to (K^{*\pm} K^\mp)(K^{*\pm} K^\mp)$ decays. If the CP-violating phase of $D^0$-$\bar{D}^0$ mixing is significant in a scenario beyond the standard model, it can also be extracted from the $K^{*\pm} K^\mp$ events.
 Physics , 2009, DOI: 10.1088/1126-6708/2009/07/097 Abstract: The observed D0 - anti-D0 oscillations provide a new stage in our search for New Physics in heavy flavour dynamics. The theoretical verdict on the observed values of x_D and y_D remains ambiguous: while they could be totally generated by Standard Model dynamics, they could also contain a sizable or even leading contribution from New Physics. Those oscillations are likely to enhance the observability of CP violation as clear manifestations of New Physics. We present general formulae for D0 - anti-D0 oscillations, concentrating on the case of negligible direct CP violation. In particular we derive a general formula for the time-dependent mixing-induced CP asymmetry in decays to a CP eigenstate and its correlation with the semileptonic CP asymmetry a_SL(D0) in D0(t) -> l nu K. We apply our formalism to the Littlest Higgs model with T-parity, using the time-dependent CP asymmetry in D -> K_S phi as an example. We find observable effects at a level well beyond anything possible with CKM dynamics. Comparisons with CP violation in the K and B systems offer an excellent test of this scenario and reveal the specific pattern of flavour and CP violation in the D0 - anti-D0 system predicted by this model. We discuss a number of charm decays that could potentially offer an insight in the dynamics of CP violation in D decays. We also apply our formalism to B_s - anti-B_s mixing.
 High Energy Physics - Phenomenology , 2007, Abstract: Recent developments for mixing and CP violation in the D0 and Bs systems are reviewed, including (i) the recently emerging evidence for D0-D0bar mixing and the interpretations of the measurements; (ii) the theoretical status of the calculations of Delta(Gamma_D) and Delta(m_D); (iii) some implications of the measurement of Bs mixing for new physics.
 Physics , 2009, DOI: 10.1103/PhysRevD.80.076008 Abstract: The two kinds of indirect CP violation in neutral meson systems are related, in the absence of new weak phases in decay. The result is a model-independent expression relating CP violation in mixing, CP violation in the interference of decays with and without mixing, and the meson mass and width differences. It relates the semileptonic and time-dependent CP asymmetries; and CP-conjugate pairs of time-dependent $D^0$ CP asymmetries. CP violation in the interference of decays with and without mixing is related to the mixing parameters of relevance to model building: the off-diagonal mixing matrix elements |M12|, |Gamma12|, and phi12 = arg(M12 /Gamma12). Incorporating this relation into a fit to the D0 -\overline{D0} mixing data implies a level of sensitivity to |phiD12| of 0.10 [rad] at 1 sigma. The formalism is extended to include new weak phases in decay, and in Gamma12. The phases are highly constrained by direct CP violation measurements. Consequently, the bounds on |phiD12| are not significantly altered, and the effects of new weak phases in decay could be difficult to observe at a high luminosity flavor factory (D0) or at the LHC (Bs) via violations of the above relations, unlike in direct CP violation.
 A. Zupanc Physics , 2011, Abstract: We review recent experimental results on D0 -D0bar mixing and CP violation charm decays. These studies provide complementary constraints on many different extensions of the Standard Model. Observation of CP violation in charm decays at the current level of experimental sensitivity would be clear signals of New Physics.
 A. J. Schwartz Physics , 2009, Abstract: We present the most recent set of world averages for D0-D0bar mixing and CP violation parameters, as obtained by the Heavy Flavor Averaging Group from a global fit to various measurements. The values obtained for the mixing parameters when allowing for CP violation are x= (0.98 +0.24 -0.26)% and y= (0.83 +-0.16)%; the significance of mixing is 10.2 sigma. There is no evidence for CP violation at the current level of sensitivity.
 R. Van Kooten for the D0 Collaboration Physics , 2010, Abstract: An analysis from the D0 Collaboration measuring the charge asymmetry A^b_sl of like-sign dimuon events due to semileptonic b-hadron decays at the Fermilab Tevatron Collider is described. It differs by 3.2 standard deviations from the Standard Model prediction to provide first evidence of CPT-invariant anomalous CP violation in the mixing of neutral B mesons, and is compared to the CP-violating phase obtained from a D0 analysis of the time-dependent decay angles in B0_s -> J/psi phi. If CPT violation is allowed, the dimuon asymmetry also yields the first sensitivity to CPT violation in the B0_s system.
 Statistics , 2012, DOI: 10.1103/PhysRevD.87.012004 Abstract: We present a measurement of D0-D0bar mixing and CP violation using the ratio of lifetimes simultaneously extracted from a sample of D0 mesons produced through the flavor-tagged process D*+ -> D0 pi+, where D0 decays to K-+pi+-, K-K+, or pi-pi+, along with the untagged decays D0 -> K-+pi+- and D0 -> K-K+. The lifetimes of the CP-even, Cabibbo-suppressed modes K-K+ and pi-pi+ are compared to that of the CP-mixed mode K-+pi+- in order to measure yCP and DeltaY. We obtain yCP = [0.72 +- 0.18 (stat) +- 0.12 (syst)]% and DeltaY = [0.09 +- 0.26 (stat) +- 0.06 (syst)]%, where DeltaY constrains possible CP violation. The yCP result excludes the null mixing hypothesis at 3.3 sigma significance. This analysis is based on an integrated luminosity of 468 fb-1 collected with the BaBar detector at the PEP-II asymmetric-energy e+e- collider.
 A. J. Schwartz Physics , 2007, Abstract: We review searches for mixing and CP violation in the D0-D0bar system and discuss the first evidence for mixing recently obtained by the Belle and BABAR collaborations. We also present world average values for the mixing parameters x=Delta m/Gamma and y=Delta Gamma/(2 Gamma) as calculated by the Heavy Flavors Averaging Group.
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