相关论文: D0-anti-D0 mixing
We prove that $D^0$-$\bar D^0$ mixing in the standard model occurs only at second order in U-spin breaking. The U-spin subgroup of SU(3) is found to be a powerful tool for analyzing the cancellation of intermediate-state contributions to…
$D^0-\bar{D}^0$ mixing at a detectable level requires the presence of new physics and may lead to some observable effects in weak decays of $B$ mesons. We show that $CP$ violation induced by $D^0-\bar{D}^0$ mixing can manifest itself in the…
We study the consequences of the large dimuon asymmetry observed at D0. Physics beyond the standard model (SM) in $B_s-\bar B_s$ mixing is required to explain the data. We first present a detailed analysis for model independent constraints…
The D0 collaboration has reported a 3.2 \sigma deviation from the Standard Model (SM) prediction in the like-sign dimuon charge asymmetry. New physics beyond the SM in B_s - \bar B_s mixing is needed to explain the data. In this paper, we…
The SM predictions for CP violating effects in D meson systems are highly suppressed at the per mill level. Therefore, any experimental evidence for a sizable CP violation in D0-D0bar mixing would unambiguously point towards a New Physics…
An overview of selected experimental results in the field of $D^0$-$\bar{D}^0$ oscillations is presented. The average results for the mixing parameters, $x=(0.89\pm{0.26\atop 0.27})%$ and $y=(0.75\pm{0.17\atop 0.18})%$, exclude the…
We present preliminary results of several analyses searching for the effects of CP violation and mixing in the decay of $D^0$ mesons. We find no evidence of CP asymmetry in five different two-body decay modes of the $D^0$ to pairs of light…
We analyze the neutral meson mixing by directly solving the dispersion relation obeyed by the mass and width differences of the two meson mass eigenstates. We solve for the parameters $x$ and $y$, proportional to the mass and width…
The mixings of $d_R$ quarks, hidden from view in Standard Model (SM), are naturally the largest if one has an Abelian flavor symmetry. With supersymmetry (SUSY) their effects can surface via $\tilde d_R$ squark loops. Squark and gluino…
New physics effects may yield a detectable mass difference in the D0-D0bar system, Delta m_D. Here we show that this has an important impact on some B --> D decays. The effect involves a new source of CP violation, which arises from the…
We calculate the parameters $x$ and $y$ for the $D$ meson mixing in the Standard Model by considering a dispersion relation between them. The dispersion relation for a fictitious charm quark of arbitrary mass squared $s$ is turned into an…
We report on a study of CP Violation in D0-D0bar mixing and Electric Dipole Moments in the framework of supersymmetric alignment models. Both classes of observables are strongly suppressed in the Standard Model and highly sensitive to new…
We discuss Standard Model (SM) and New Physics (NP) descriptions of D0 mixing. The SM part of the discussion addresses both quark level and hadron level contributions. The NP part describes our recent works on the rate difference Delta…
The motivation most often cited in searches for D0-anti-D0 mixing and CP-violation in charm system lies with the possibility of observing a signal from new physics which dominates that from the Standard Model. We review recent theoretical…
The BaBar and Belle collaborations have recently found evidence for mixing within the D meson system. We present some of the mixing search techniques used by BaBar and their status as of the beginning of the summer 2007. These have…
The decay rates of $D^+\to\pi^+\pi^0$ and $D^0\to K^+\pi^-$ recently measured by CLEO give the ratios $R_1=2|V_{cs}/V_{cd}|^2\Gamma(D^+\to \pi^+\pi^0)/\Gamma(D^+\to\bar{K}^0 \pi^+)=3.29\pm 1.16$ and…
Masses and decay constants of scalar $D_0$ and $D_{s0}$ mesons in isospin asymmetric strange hadronic matter at finite temperature are evaluated using QCD sum rules and chiral SU(3) model. In-medium light quark condensates, $\left\langle…
Combining the measured B_s mixing with b \to s\ell^+\ell^- rate data, we find a sizable 4 generation t' quark effect is allowed, for example with m_{t'} \sim 300 GeV and V_{t's}^*V_{t'b} \sim 0.025 e^{\pm i 70^\circ}, which could underly…
A fit of amplitudes to the experimental branching ratios to two mesons is used to construct a new estimate of neutral $D$ mixing which includes $SU(3)$ breaking. The result is dominated by the experimental uncertainties. This suggests that…
We observe evidence for $D^0 - \bar{D}^0$ mixing by measuring the difference in apparent lifetime when a $D^0$ meson decays to the CP eigenstates $K^+K^-$ and $\pi^+\pi^-$, and when it decays to the final state $K^-\pi^+$. We find…