arXiv subjects

Shu-Min Zhao

Publications and source records attributed to Shu-Min Zhao.

99 records · Page 6Linked to original sources

arXiv2013

Lepton-flavor violation and $(g-2)_μ$ in the $μν$SSM

Within framework of the $μ$ from $ν$ Supersymmetric Standard Model ($μν$SSM), exotic singlet right-handed neutrino superfields induce new sources for lepton-flavor violation. In this work, we investigate some lepton-flavor violating processes in detail in the $μν$SSM. The numerical results indicate that the branching ratios for lepton-flavor violating processes $μ\rightarrow eγ$, $τ\rightarrowμγ$ and $μ\rightarrow3e$ can reach $10^{-12}$ when $\tanβ$ is large enough, which can be detected in near future. We also discuss the constraint on the relevant parameter space of the model from the muon anomalous magnetic dipole moment. In addition, from the scalars for the $μν$SSM we strictly separate the Goldstone bosons, which disappear in the physical gauge.

hep-ph↗

arXiv2013

Gauged baryon and lepton numbers in supersymmetry with a $125\;{\rm GeV}$ Higgs

Assuming that the Yukawa couplings between the Higgs and exotic quarks cannot be ignored, we analyze the signals of decay channels $h\rightarrowγγ$ and $h\rightarrow VV^*\;(V=Z,\;W)$ with the Higgs mass around $125\;{\rm GeV}$ in a supersymmetric extension of the standard model where baryon and lepton numbers are local gauge symmetries. Adopting some assumptions on relevant parameter space, we can account for the experimental data on Higgs from ATLAS and CMS naturally.

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arXiv2012

Search for lepton flavor violation in supersymmetric models via meson decays

Considering the constraints from the experimental data on $μ\rightarrow eγ$, $μ\rightarrow3e$, $μ-e$ conversion etc., we analyze the Lepton Flavor Violating decays $ϕ(J/Ψ,Υ(1S)) \rightarrow e^+μ^-(μ^+τ^-)$ in the scenarios of the minimal supersymmetric extensions of Standard Model with seesaw Mechanism. Numerically, there is parameter space that the LFV processes of $J/Ψ(Υ)\rightarrowμ^+τ^-$ can reach the upper experimental bounds, meanwhile the theoretical predictions on $μ\rightarrow eγ$, $μ\rightarrow3e$, $μ-e$ conversion satisfy the present experimental bounds. For searching of new physics, Lepton Flavor Violating processes $J/Ψ(Υ)\rightarrowμ^+τ^-$ may be more promising and effective channels.

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arXiv2007

Comprehensive Calculations on the OZI-forbidden Nonleptonic Decays of Orthoquarkonia $J/ψ(Υ)\to ππ,ρπ$

In this work, we calculate the decay rates of the OZI-forbidden processes $J/ψ(Υ)\to ππ, ρπ$ at the order of the leading-twist distribution amplitude. The process of $J/ψ(Υ)\to π^+ π^-$ violates isospin conservation and the amplitude is explicitly proportional to the isospin violation factor $m_u-m_d$, our numerical results on their decay rates are consistent with the data. The process $J/ψ(Υ)\to ρπ$ violates the hadronic helicity conservation and should be suppressed, as indicated in literature, its decay rate can only be proportional to $m_q^2$ at the order of leading twist. Our theoretical evaluation confirms this statement that the theoretical evaluation on $Γ(J/ψ(Υ)\to ρπ)$ is almost one order smaller than the data unless the model parameters take certain extreme values. It may imply that the sizable branching ratio of $J/ψ(Υ)\to ρπ$ should be explained by either higher twist contributions or other mechanisms.

hep-ph↗

arXiv2007

Study on $B_s\to D_{sJ}(2317,2460)l\barν$ Semileptonic Decays in the CQM Model

Assuming $D^*_{sJ}(2317)$ and $D_{sJ}(2460)$ to be the $(0^+,1^+)$ chiral partners of regular $D_{s}(1968)$ and $D^{*}_{s}(2112)$, we calculate the semileptonic decays of $B_s$ to $D_s(1968)$, $D^*_s(2112)$, $D_{sJ}^{*}(2317)$, $D_{sJ}(2460)$ in terms of the Constituent Quark Meson (CQM) model. The large branching ratios of the semileptonic decays of $B_s$ to $D_{sJ}^{*}(2317)$ and $D_{sJ}(2460)$ indicate that those two semileptonic decays should be seen in future experiments.

hep-ph↗

arXiv2006

Study on Decays of $D_{sJ}^{*}(2317)$ and $D_{sJ}(2460)$ in terms of the CQM Model

Based on the assumption that $D_{sJ}^{*}(2317)$ and $D_{sJ}(2460)$ are the $(0^+, 1^+)$ chiral partners of $D_{s}$ and $D^*_s$, we evaluate the strong pionic and radiative decays of $D_{sJ}^{*}(2317)$ and $D_{sJ}(2460)$ in the Constituent Quark Meson (CQM) model. Our numerical results of the relative ratios of the decay widths are reasonably consistent with data.

hep-ph↗

arXiv2005

Study on production of exotic $0^+$ meson $D_{sJ}^{*}(2317)$ in decays of $ψ(4415)$

The newly observed $D_{sJ}^*$ family containing $D_{sJ}^{*}(2317)$, $D_{sJ}(2460)$ and $D_{sJ}(2632)$ attracts great interests. Determining their structure may be important tasks for both theorists and experimentalists. In this work we use the heavy quark effective theory (HQET) and a non-relativistic model to evaluate the production rate of $D_{sJ}^{*}(2317)$ from the decays of $ψ(4415)$, and we find that it is sizable and may be observed at BES III and CLEO, if it is a p-wave excited state of $D_s(1968)$. Unfortunately, the other two members of the family cannot be observed through decays of charmonia, because of the constraints from the final state phase space.

hep-ph↗

arXiv2005

Revisiting the OZI-forbidden Radiative Decays of Orthoquarkonia

It is interesting to investigate the OZI-forbidden radiative orthoquarkonium decays $J/ψ\to γπ^0, γη$ and $γη'$ in perturbative QCD. In this work without the approximations adopted in literature we carry out a full one-loop calculation which involves integrations of 4-point and 5-point loop functions. Our numerical results are in agreement with the present data. We also briefly discuss the decays of $J/ψ\to γ+ρ^0$, as well as $Υ\to π^0γ, ηγ, η'γ$.

hep-ph↗

arXiv2003

Lepton Dipole Moments and Rare Decays in the CP-violating MSSM with Nonuniversal Soft-Supersymmetry Breaking

We investigate the muon anomalous magnetic dipole moment (MDM), the muon electric dipole moment (EDM) and the lepton-flavour-violating decays of the $τ-$lepton, $τ\to μγ$ and $τ\to 3μ$, in the CP-violating Minimal Supersymmetric Standard Model (MSSM) with nonuniversal soft-supersymmetry breaking. We evaluate numerically the muon EDM and the branching ratios $B(τ\to μγ)$ and $B(τ\to 3μ)$, after taking into account the experimental constraints from the electron EDM and muon MDM. Upon imposition of the experimental limits on our theoretical predictions for the aforementioned branching ratios and the muon MDM, we obtain an upper bound of about $10^{-23} e\cdot cm$ on the muon EDM which lies well within the explorable reach of the proposed experiment at BNL.

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