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Tian-hong Wang

Publications and source records attributed to Tian-hong Wang.

6 recordsLinked to original sources
arXiv2020

The weak decay $B_c$ to $Z(3930)$ and $X(4160)$ by Bethe-Salpeter method

Considering $Z(3930)$ and $X(4160)$ as $χ_{c2}(2P)$ and $χ_{c2}(3P)$ states, the semileptonic and nonleptonic of $B_c$ decays to $Z(3930)$ and $X(4160)$ are studied by the improved Bethe-Salpeter(B-S) Method. The form factors of decay are calculated through the overlap integrals of the meson wave functions in the whole accessible kinematical range. The influence of relativistic corrections are considered in the exclusive decays. Branching ratios of $B_c$ weak decays to $Z(3930)$ and $X(4160)$ are predicted. Some of the branching ratios are: $Br(B_c^+\to Z(3930)e^+ν_e)$$=(3.03^{+0.09}_{-0.16})\times 10^{-4}$ and $Br(B_c^+\to X(4160)e^+ν_e)$$=(3.55^{+0.83}_{-0.35})\times 10^{-6}$. These results may provide useful information to discover $Z(3930)$ and $X(4160)$ and the necessary information for the phenomenological study of $B_c$ physics.

hep-ph↗
arXiv2020

Relativistic calculations of $R(D^{(*)})$, $R(D^{(*)}_s)$, $R(η_c)$ and $R(J/ψ)$

Recently, the deviation of the ratios $R(D)$, $R(D^{*})$ and $R(J/ψ)$ have been found between experimental data and the Standard Model predictions, which may be the hint of New Physics. In this work, we calculate these ratios within the Standard Model by using the improved instantaneous Bethe-Salpeter method. The emphasis is pad to the relativistic correction of the form factors. The results are $R(D)=0.312 ^{+0.006}_{-0.007}$, $R(D^*)= 0.249^{+0.001}_{-0.002}$, $R(D_s)=0.320 ^{+0.009}_{-0.009}$, $R(D^*_s)=0.251 ^{+0.002}_{-0.003}$, $R(η_c)=0.384 ^{+0.032}_{-0.042}$, and $R(J/ψ)=0.267 ^{+0.009}_{-0.011}$, which are consistent with predictions of other models and the experimental data. The semileptonic decay rates and corresponding form factors at zero recoil are also given.

hep-ph↗
arXiv2018

The Strong Decays of $P-$wave Mixing Heavy-Light $1^+$ States

Many $P-$wave mixing heavy-light $1^+$ states have not been discovered by experiment, some of them have been discovered but without the information of width, or with large uncertainty widths. In this paper, we study the strong decays of $P-$wave mixing heavy-light $1^+$ states $D^0$, $D^\pm$, $D_s^\pm$, $B^0$, $B^\pm$ and $B_s$ by the improved Bethe-Salpeter(B-S) method in two conditions of mixing angle $θ$: one is $θ=35.3^\circ$; another is considering the correction to mixing angle $θ=35.3^\circ+θ_1$. And we get some valuable predictions of the strong decay widths: $Γ(D_1^{\prime0})=232$ MeV, $Γ(D_1^0)=21.5$ MeV, $Γ(D_1^{\prime\pm})=232$ MeV, $Γ(D_1^\pm)=21.5$ MeV, $Γ(D_{s1}^{\prime\pm})=0.0101$ MeV, $Γ(D_{s1}^{\pm})=0.950$ MeV, $Γ(B_1^{\prime\pm})=263$ MeV, $Γ(B_1^{\pm})=16.8$ MeV, $Γ(B_{s1}^{\prime})=0.01987$ MeV and $Γ(B_{s1})=0.412$ MeV. We find that the decay widths of $D_{s1}^{\pm}$ and $B_{s1}$ are very sensitive to the mixing angle. And our results will provide the theoretical assistance by the future experiments.

hep-ph↗
arXiv2017

Testing the nature of neutrinos from four-body $τ$ decays

This paper is designed to discuss four-body lepton number violating tau decay. We study the processes $τ^+ \to e^+ e^+ π^- ν_τ$ and $τ^+ \to e^+ e^+ π^- ν_e$ to determine the nature of neutrino. The first process violates lepton number by two units which can only happen through an internal Majorana. The second one conserves lepton number but violates lepton flavor which can take place with both Majorana neutrino and Dirac neutrino. We calculate their branching ratio $Br$ and differential branching ratio $dBr/dE_π$ to distinguish Majorana neutrino vs. Dirac neutrino. We also propose the possibility of experiment to perform this detection.

hep-ph↗
arXiv2016

The Production of $X(3940)$ and $X(4160)$ in $B_c$ decays

Considering $X(3940)$ and $X(4160)$ as $η_c(3S)$ and $η_c(4S)$, we study the productions of $X(3940)$ and $X(4160)$ in exclusive weak decays of $B_c$ meson by the improved Bethe-Salpeter(B-S) Method. Using the relativistic B-S equation and Mandelstam formalism, we calculate the corresponding decay form factors. The predictions of the corresponding branching ratios are: $Br(B_c^+\to X(3940)e^+ν_e)$$=1.0\times10^{-4}$ and $Br(B_c^+\to X(4160)e^+ν_e)=2.4\times10^{-5}$. That will provide us a new way to observe the $X(3940)$ and $X(4160)$ in the future, as well as to improve the knowledge of $B_c$ meson decay.

hep-ph↗
arXiv2016

Semi-leptonic Production of $D_{sJ}(3040)$ and $D_J(3000)$ in $B_s$ and $B$ Decays

In this paper, we study the productions of the newly detected states $D_{sJ}(3040)$ and $D_J(3000)$ observed by BABAR Collaboration and LHCb Collaboration. We assume these states to be the $D_s(2P)$ and $D(2P)$ states with the quantum number $J^P=1^+$ in our work. The results of improved Bethe-Salpeter method indicate that the semi-leptonic decays via $B_s$ and $B$ into $D_{sJ}(3040)$ and $D_J(3000)$ have considerable branching ratios, for example, Br($\bar{B}_s^0 \rightarrow D{_{sJ}^+}(3040)e^-\barν{_e}$)=$5.79\times10^{-4}$, Br($\bar{B}^0\rightarrow D_{J}^+(3000)e^-\barν{_e}$)=$2.63\times10^{-4}$, which shows that these semi-leptonic decays can be accessible in experiments.

hep-ph↗