相关论文: Testing the standard model with $D_{(s)} \to K_1 (…

We reexamine, update and extend a suggestion we made fifteen years ago for measuring the photon polarization in $b \to s\gamma$ by observing in $B \to K\pi\pi\gamma$ an asymmetry of the photon with respect to the $K\pi\pi$ plane.…

We work out the phenomenology of untagged time-dependent analysis with radiative $D^0$-decays into CP eigenstates, which allows to probe the photon polarization by means of the charm mesons' finite width difference. We show that $D^0 \to…

We study decay distributions in B -> K pi pi gamma, combining contributions from several overlapping resonances in a K pi pi mass range near 1400 MeV, (1^+) K_1(1400), (2^+) K^*_2(1430) and (1^-) K^*(1410). A method is proposed for using…

The time-dependent CP asymmetry in exclusive B^0(t) -> K^{*0}\gamma decays has been proposed as a probe of new physics in B decays. Recently, this method was extended to radiative decays into multibody hadronic final states such as B^0(t)->…

A method is proposed to measure the photon polarisation parameter $\lambda_\gamma$ in $b\to s\gamma$ transitions using an amplitude analysis of $B\to K\pi\pi\gamma$ decays. Simplified models of the $K\pi\pi$ i system are used to simulate…

We study radiative charm decays $D \to P_1 P_2 \gamma$, $P_{1,2}=\pi,K$ in QCD factorization at leading order and within heavy hadron chiral perturbation theory. Branching ratios including resonance contributions are around $\sim 10^{-3}$…

We propose a way of measuring the photon polarization in radiative B decays into K resonance states decaying to K\pi\pi, which can test the Standard Model and probe new physics. The photon polarization is shown to be measured by the up-down…

Recently the radiative B decay to the strange axial-vector mesons, B --> K1(1270) gamma, has been observed with rather large branching ratio. This process is particularly interesting as the subsequent K1 decay into its three body final…

We compute 10 radiative three-body decays of charged charmed mesons $D^+ \to P^+ P^0 \gamma$ and $D_s \to P^+ P^0 \gamma$, $P=\pi, K$, in leading order QCDF, HH$\chi$PT and the soft photon approximation. We work out decay distributions and…

We report a sensitive study of measuring $b\to s\gamma$ photon polarisation in $D^{0}\to K_1(1270)^-e^+\nu_e$ with an integrated luminosity of $\mathcal L$ = 1 ab$^{-1}$ at a center-of-mass energy of 3.773 GeV at future Super Tau Charm…

Charge-parity (CP) asymmetries in charm decays are extremely suppressed in the Standard Model and may well be dominated by new physics contributions. The LHCb collaboration reported the results of direct CP asymmetry measurements in $D^0\to…

In the Standard Model, the photon emitted in b->s\gamma decays is predicted to be left-handed polarized. We discuss the types of New Physics which can produce a deviation from this prediction, focusing on the Minimal Supersymmetric Standard…

Polarized $\Lambda_b \to \Lambda \gamma$ decays at the Z pole are shown to be well suited for probing a large variety of New Physics effects. A new observable is proposed, the angular asymmetry between the $\Lambda_b$ spin and photon…

A sizable right-handed photon polarization in $b\to s\gamma$ is a clear signal for new physics. In this work we point out that the photon helicity in $b\to s\gamma$ can be unambiguously extracted by combining the measurements in $B\to…

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…

The standard model prediction for the $B\to X_{s,d}\gamma$ decay amplitude with a right-handed photon is believed to be tiny, suppressed by $m_{s,d}/m_b$, compared to the amplitude with a left-handed photon. We show that this suppression is…

We re-examine the possibility to measure the photon polarization in $B \to K^*\gamma$ decays, via decays in which the photon subsequently undergoes nuclear conversion to a lepton pair. We obtain compact expressions for the full…

The recent measurement of the CP-asymmetry in the decay $D \to K^+ K^-$ by LHCb, combined with $\Delta A_{\text{CP}}$, evidences a sizable CP-asymmetry in $D \to \pi^+ \pi^-$ decays, which requires a dynamical enhancement of standard model…

The measurement of the time-dependent CP-asymmetry of $B^0 \to K_S^0 \pi^+ \pi^- \gamma$ decays is sensitive to contributions from physics beyond the Standard Model. To translate this measurement into a constraint on new physics, it is…

We present standard model (SM) estimates for exclusive $c \to u \gamma$ processes in heavy quark and hybrid frameworks. Measured branching ratios ${\cal{B}}(D^0 \to (\phi, \bar K^{*0}) \gamma)$ are at or somewhat exceeding the upper range…