Related papers: Coloured Scalars Mediated Rare Charm Meson Decays …
We investigate nucleon decays to light invisible fermion mediated by the coloured scalar $\bar S_1= (\bar 3, 1, -2/3)$ and compare them with the results coming from the mediation of $S_1 = (\bar 3,1,1/3)$. In the case of $\bar S_1= (\bar 3,…
The $\bar{B}_{q}^{\ast}$ ${\to}$ $DP$, $DV$ weak decays are studied with the perturbative QCD approach, where $q$ $=$ $u$, $d$ and $s$; $P$ and $V$ denote the ground $SU(3)$ pseudoscalar and vector meson nonet. It is found that the…
Inspired by the recent observation of the $D^0-\bar D^0$ mixing, we explore the effects of colored scalars on the $\Delta C=2$ process in diquark models. As an illustration, we investigate the diquarks with the quantum numbers of (6, 1,…
We investigate the possibility that scalar leptoquarks generate consequential effects on the flavor-changing neutral-current decays of charmed hadrons into final states with missing energy ($\not\!\!E$) carried away by either standard model…
We evaluate the decay branching ratios of $\chi_{c1}\to PS$, in a quark model parametrization scheme, where $P$ and $S$ stand for pseudoscalar and scalar meson, respectively. An interesting feature of this decay process is that the…
Based on the assumption of two-quark structure for the light scalar mesons, within the framework of perturbative QCD approach, we investigate the $B_{q}\to D_{(s)}^{(*)} S(q=u,d,s)$ decays induced by $b\to u $ transition, where $S$ denotes…
The study on the charmed scalar meson spectroscopy has become a hot topic both experimentally and theoretically. The $B_{(s)}$ decays provide an ideal place to study their property. We employ the $B$-meson light-cone sum rules to compute…
The $B^{-} \to \chi_{c0} K^{-}$ decay which has no visible factorizable amplitude, could be induced by the Cabibbo-allowed, color-favored $B^{-} \to D_{s}D^{*0}$, $B^{-} \to D^{*0}_{s}D^{0}$ and $B \to D_{s}^{*}D^{*}$ via the rescattering…
We study the invisible scalar of $S$ in charmed meson and baryon decays with flavor-changing neutral currents (FCNCs) based on the model-independent effective Lagrangian between the quarks and invisible scalar. From the bounds of the…
The presence of a colored scalar that is a weak doublet with fractional electric charges of $|Q|=2/3$ and $|Q|=5/3$ with mass below 1,TeV can provide an explanation of the observed branching ratios in $B \to D^{(*)} \tau \bar \nu$ decays.…
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…
The nonleptonic weak decays of charmed mesons into a scalar meson and a pseudoscalar meson are studied. The scalar mesons under consideration are $\sigma$ [or $f_0(600)$], $\kappa$, $f_0(980)$, $a_0(980)$ and $K^*_0(1430)$. A consistent…
We study the invisible Majorana fermions of $\chi$ in bottomed baryon decays with flavor-changing neutral currents (FCNCs) based on the model-independent effective Lagrangian between the quarks and invisible particles. From the bounds of…
There are two apparent puzzles connected with the two-body and three-body doubly charmed baryonic B decays. First, earlier calculations based on QCD sum rules or the diquark model predict $Br(\bar B^0\to\Xi_c^+\bar\Lambda_c^-)\approx…
We study the novel decays $B^{*}\to B\gamma\gamma $ and $D^{*}\to D\gamma \gamma $ using the framework of the Heavy Meson Chiral Lagrangian (HM$\chi$L) to leading order in chiral perturbation theory. The branching ratios of these decays are…
In the quark-diagram scheme, we study the charmed baryon decays of ${\bf B}_c\to {\bf B}^* M$, where ${\bf B}_c$ is $\Lambda_c^+$ or $\Xi_c^{+(0)}$, together with ${\bf B}^*$ ($M$) the decuplet baryon (pseudoscalar meson). It is found that…
The flavor-changing neutral current decay processes of the $B$ and $B_c$ mesons with the final states involving spin-$1/2$ particles are investigated. By considering the background of the Standard Model where $\nu\bar\nu$ contributes the…
The chiral symmetry of QCD requires energy-dependent pionic strong interactions at low energies. This constraint, however, is not fulfilled by the usual Breit--Wigner parameterization of pionic resonances, leading to masses larger than the…
The SU(3) quark model encounters a great challenge in describing even-parity mesons. Specifically, the $q\bar q$ quark model has difficulties in understanding the light scalar mesons below 1 GeV, scalar and axial-vector charmed mesons and…
We study color allowed $\Lambda_b\to \Lambda^{(*,**)}_c M^-$, $\Xi_b\to\Xi_c^{(**)} M^-$ and $\Omega_b\to\Omega^{(*)}_c M^-$ decays with $M=\pi, K,\rho, K^*, D, D_s, D^*, D^*_s, a_1$, $\Lambda^{(*,**)}_c=\Lambda_c$, $\Lambda_c(2595)$,…