arXiv subjects

Gongru Lu

Publications and source records attributed to Gongru Lu.

At least 19 recordsLinked to original sources

arXiv2018

$B_{u}$ ${\to}$ $ψM$ decays and $S$-$D$ wave mixing effects

The $B_{u}$ ${\to}$ $ψM$ decays are studied with the perturbative QCD approach, where the psion $ψ$ $=$ $ψ(2S)$, $ψ(3770)$, $ψ(4040)$ and $ψ(4160)$, and the light meson $M$ $=$ $π$, $K$, $ρ$ and $K^{\ast}$. The factorizable and nonfactorizable contributions, and the $S$-$D$ wave mixing effects on the psions are considered in the calculation. With appropriate inputs, the branching ratios for the $B_{u}$ ${\to}$ $ψK$ decays are generally coincident with the experimental data within errors. However, due to the large theoretical and experimental errors, it is impossible for the moment to give a severe constraint on the $S$-$D$ wave mixing angles.

hep-ph↗

arXiv2017

$Υ(nS)$ ${\to}$ $B_{c}ρ$, $B_{c}K^{\ast}$ decays with perturbative QCD approach

Inspired by the potential prospects of $Υ(nS)$ data samples ($n$ $=$ $1$, $2$, $3$) at LHC and SuperKEKB, $Υ(nS)$ ${\to}$ $B_{c}ρ$, $B_{c}K^{\ast}$ decays are studied phenomenologically with pQCD approach. Branching ratios for $Υ(nS)$ ${\to}$ $B_{c}ρ$ and $B_{c}K^{\ast}$ decays are estimated to reach up to ${\cal O}(10^{-11})$ and ${\cal O}(10^{-12})$, respectively. Given the identification and detection efficiency of final states, searching for these weak decay modes should be fairly challenging experimentally in the future.

hep-ph↗

arXiv2017

Study of $J/ψ$ ${\to}$ $D_{s,d}V$ decays with perturbative QCD approach

Inspired by the recent measurements on two-body nonleptonic $J/ψ$ weak decay at BESIII, the charm-changing $J/ψ$ ${\to}$ $D_{s,d}V$ weak decays are studied with perturbative QCD approach, where $V$ denotes $ρ$ and $K^{\ast}$ vector mesons. It is found that branching ratio for $J/ψ$ ${\to}$ $D_{s}ρ$ decay can reach up to ${\cal O}(10^{-9})$, which is within the potential measurement capability of the future high-luminosity experiments.

hep-ph↗

arXiv2017

$J/ψ$ ${\to}$ $D_{s,d}π$, $D_{s,d}K$ decays with perturbative QCD approach

Besides the conventional strong and electromagnetic decay modes, the $J/ψ$ particle can also decay via the weak interaction in the standard model. In this paper, nonleptonic $J/ψ$ ${\to}$ $D_{s,d}π$, $D_{s,d}K$ weak decays, corresponding to the externally emitted virtual $W$ boson process, are investigated with the perturbative QCD approach. It is found that branching ratio for the Cabibbo-favored $J/ψ$ ${\to}$ $D_{s}π$ decay can reach up to ${\cal O}(10^{-10})$, which might be potentially measurable at the future high-luminosity experiments.

hep-ph↗

arXiv2017

$Υ(nS)$ ${\to}$ $B_{c}^{\ast}D$ decays with perturbative QCD approach

The $Υ(nS)$ ${\to}$ $B_{c}^{\ast}D$ weak decays ($n$ $=$ $1$, $2$, $3$) are investigated with perturbative QCD approach. It is found that the CKM-favored $Υ(nS)$ ${\to}$ $B_{c}^{\ast}D_{s}$ decays have branching ratio of ${\cal O}(10^{-10})$, which might be potentially accessible to the future LHC and SuperKEKB experiments.

hep-ph↗

arXiv2017

$B^{\ast}$ ${\to}$ $\bar{D}D$ decays with perturbative QCD approach

The nonleptonic two-body $B^{\ast}$ ${\to}$ $\bar{D}D$ weak decays are studied phenomenologically with the perturbative QCD factorization approach. It is found that the $B_{s}^{{\ast}0}$ ${\to}$ $D_{s}^{-}D_{s}^{+}$, $B_{d}^{{\ast}0}$ ${\to}$ $D_{d}^{-}D_{s}^{+}$, and $B_{u}^{{\ast}+}$ ${\to}$ $\bar{D}_{u}^{0}D_{s}^{+}$ decays have branching ratios ${\gtrsim}$ $10^{-9}$, and might be promisingly measurable at the running LHC and forthcoming SuperKEKB experiments in the future.

hep-ph↗

arXiv2017

Study of the $\bar{B}_{q}^{\ast}$ ${\to}$ $DM$ decays with perturbative QCD approach

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 branching ratios for the color-allowed $\bar{B}_{q}^{\ast}$ ${\to}$ $D_{q}ρ^{-}$ decays can reach up to $10^{-9}$ or more, and should be promisingly measurable at the running LHC and forthcoming SuperKEKB experiments in the near future.

hep-ph↗

arXiv2017

Possibility of searching for $B_{c}^{\ast}$ ${\to}$ $B_{u,d,s}V$, $B_{u,d,s}P$ decays

The $B_{c}^{\ast}$ ${\to}$ $B_{u,d,s}V$, $B_{u,d,s}P$ decays are investigated with the QCD factorization approach, where $V$ and $P$ denote the ground $SU(3)$ vector and pseudoscalar mesons, respectively. The $B_{c}^{\ast}$ ${\to}$ $B_{u,d,s}$ transition form factors are calculated with the Wirbel-Stech-Bauer model. It is found that branching ratios for the color-favored and Cabibbo-favored $B_{c}^{\ast}$ ${\to}$ $B_{s}ρ$, $B_{s}π$ decays can reach up to ${\cal O}(10^{-7})$, which might be measurable in the future LHC experiments.

hep-ph↗

arXiv2016

The $Υ(nS)$ ${\to}$ $B_{c}^{\ast}π$, $B_{c}^{\ast}K$ decays with perturbative QCD approach

Besides the traditional strong and electromagnetic decay modes, $Υ(nS)$ meson can also decay through the weak interactions within the standard model of elementary particle. With anticipation of copious $Υ(nS)$ data samples at the running LHC and coming SuperKEKB experiments, the two-body nonleptonic bottom-changing $Υ(nS)$ ${\to}$ $B_{c}^{\ast}π$, $B_{c}^{\ast}K$ decays ($n$ $=$ 1, 2, 3) are investigated with perturbative QCD approach firstly. The absolute branching ratios for $Υ(nS)$ ${\to}$ $B_{c}^{\ast}π$ and $B_{c}^{\ast}K$ decays are estimated to reach up to about $10^{-10}$ and $10^{-11}$, respectively, which might possibly be measured by the future experiments.

hep-ph↗

arXiv2016

The $Υ(1S)$ ${\to}$ $B_{c}ρ$ decay with perturbative QCD approach

With the potential prospects of the $Υ(1S)$ data samples at the running LHC and upcoming SuperKEKB, the $Υ(1S)$ ${\to}$ $B_{c}ρ$ weak decays are studied with the pQCD approach. It is found that (1) the lion's share of branching ratio comes from the longitudinal polarization helicity amplitudes; (2) branching ratio for the $Υ(1S)$ ${\to}$ $B_{c}ρ$ decay can reach up to ${\cal O}(10^{-9})$, which might be hopefully measurable.

hep-ph↗

arXiv2016

Study of the $Υ(1S)$ ${\to}$ $B_{c}D_{s}^{\ast}$ decay with pQCD approach

The $Υ(1S)$ ${\to}$ $B_{c}D_{s}^{\ast}$ weak decay is studied with the perturbative QCD approach firstly. It is found that (1) main contributions to branching ratio come from the longitudinal and parallel helicity amplitudes, (2) branching ratio, longitudinal and parallel polarization fractions are sensitive to the wave functions of the $Υ(1S)$ meson, (3) branching ratio for the $Υ(1S)$ ${\to}$ $B_{c}D_{s}^{\ast}$ decay can reach up to $10^{-9}$, which might be promisingly measured by the future experiments.

hep-ph↗

arXiv2014

Study of the $B_{c}$ ${\to}$ $B_{s}π$ decay with the perturbative QCD approach

The $B_{c}$ ${\to}$ $B_{s}π$ decay is studied with the perturbative QCD approach. Three types of wave functions for $B_{s}$ meson are considered. The transition form factor $F_{0}^{B_{c}{\to}B_{s}}(0)$ and the branching ratio ${\cal B}r(B_{c}{\to}B_{s}π)$ are sensitive to the model of the $B_{s}$ meson wave functions. With appropriate inputs, our estimate on ${\cal B}r(B_{c}{\to}B_{s}π)$ is comparable with the recent LHCb measurement. A clear signal of $B_{c}$ ${\to}$ $B_{s}π$ decay should be easily observed at the Large Hadron Collider.

hep-ph↗

arXiv2014

Study of the $η^{\prime}$ ${\to}$ $Ve^{+}e^{-}$ decay with hidden local symmetry model

Within the hidden local symmetry framework, the Dalitz decay $η^{\prime}$ ${\to}$ $Ve^{+}e^{-}$ is studied with the vector meson dominance model. It is found that the partial width $Γ(η^{\prime}{\to}ωe^{+}e^{-})$ ${\approx}$ $40$ eV and branching ratio ${\cal B}(η^{\prime}{\to}ωe^{+}e^{-})$ ${\approx}$ $2{\times}10^{-4}$, and $Γ(η^{\prime}{\to}ρe^{+}e^{-})$ ${\approx}$ $10Γ(η^{\prime}{\to}ωe^{+}e^{-})$ and ${\cal B}(η^{\prime}{\to}ρe^{+}e^{-})$ ${\approx}$ $10{\cal B}(η^{\prime}{\to}ωe^{+}e^{-})$. The maximum position of the dilepton distribution is $m_{e^{+}e^{-}}$ ${\approx}$ $1.33$ MeV. These decays are measurable with the advent of high statistics $η^{\prime}$ experiments.

hep-ph↗

arXiv2014

Phenomenological study of the $B_{c}$ ${\to}$ $BP$, $BV$ decays with perturbative QCD approach

Inspired by the recent LHCb measurements and forthcoming great potential on $B_{c}$ meson, we study the exclusive $B_{c}$ ${\to}$ $B_{q}P$, $B_{q}V$ decays with the perturbative QCD approach, where $q$ $=$ $u$, $d$, $s$; $P$ and $V$ denote the lightest pseudoscalar and vector $SU(3)$ nonet meson, respectively. By retaining the quark transverse momentum, employing the Sudakov factors, and choosing the typical scale as the maximum virtualities of the internal particles, we calculate the $B_{c}$ ${\to}$ $B$ transition from factors, and our results show that about 90\% contribution to form factors come from the $α_{s}/π$ $<$ $0.3$ region. The contributions of penguin and annihilation to branching ratios are very small due to the serious suppression by the CKM factors. There is some hierarchy relations among the $B_{c}$ ${\to}$ $BP$, $BV$ decays. The branching ratios for $B_{c}$ ${\to}$ $B_{d,s}π$, $B_{d,s}ρ$, $B_{s}K$ are large and could be measured by the running LHCb.

hep-ph↗

arXiv2013

Study on the properties of the coupling constants of $J/ψ\rightarrow VP$ decays

Basing on the branching fractions of J/ψ\to VP from different experiments, we investigate on the properties of the coupling constants of J/ψ\to VP decays with a model-dependent approach. We find that the octet coupling constant, g_8, of strong interaction is about twice larger than that of the singlet coupling constant g_1; the electromagnetic breaking parameters g^i_E are larger than the mass breaking parameters g^i_M, moreover, the three parameters of electromagnetic effect are about equal, but the three parameters of mass effect are obviously different and their uncertainties are also large; and the phase angle between strong and electromagnetic interaction is in the range of 70^{\circ} \sim 80^{\circ}. It deepens our understanding of the coupling constant of J/ψ\to VP decays.

hep-ph↗

arXiv2013

Study of $B_{s}$ ${\to}$ $η_{c}(J/ψ)D$ decay with perturbative QCD approach

The $W$-exchange process $B_{s}$ ${\to}$ $η_{c}(J/ψ)D$ is studied with the perturbative QCD approach. Three kinds of wave functions for $B_{s}$ meson and two forms of wave functions for charmonium are considered. It is estimated that branching ratios for $B_{s}$ ${\to}$ $η_{c}\bar{D}$, $η_{c}D$, $J/ψ\bar{D}$, $J/ψD$ decays are the order of $10^{-7}$, $10^{-8}$, $10^{-8}$, $10^{-9}$, respectively, where the largest uncertainty is from wave functions. There is a possibility for measuring these decay in the near future.

hep-ph↗

arXiv2011

Searches for the technicolor signatures via gg --> W^{\pm}π_t^{\mp} at the Large Hadron Collider

In this paper we calculate the production of a charged top pion in association with a W boson via gg fusion at the CERN Large Hadron Collider in the context of the topcolor assisted technicolor model. We find that, the total cross section of pp --> gg --> W^{\pm}π_t^{\mp}, is several dozen femtobarns with reasonable values of the parameters, and the total cross section of pp --> W^{\pm}π_t^{\mp} can reach a few hundred femtobarns when we consider the sum of the contributions of these two parton subprocesses gg --> W^{\pm}π_t^{\mp} and b\bar{b} --> W^{\pm}π_t^{\mp}.

hep-ph↗

arXiv2010

The flavor-changing top-charm associated productions at ILC in littlest Higgs model with T parity

The littlest Higgs model with T-parity (LHT) has new flavor-changing (FC) couplings with the Standard Model (SM) quarks, which do not suffer strong constraints from electroweak precision data. So these FC interactions may enhance the cross sections of some flavor-changing neutral-current (FCNC) processes. In this work, we study the FC top-charm associated productions via $e^{-}γ$ collision at the ILC. We find that the cross sections are sensitive to the mirror quark masses. With reasonable values of the parameters, the cross sections may reach the detectable level and provide useful information about the relevant parameters in the LHT model, especially setting an upper limit on the mirror quark masses.

hep-ph↗