arXiv subjects

Zhi-Gang Wang

Publications and source records attributed to Zhi-Gang Wang.

At least 181 records · Page 10Linked to original sources

arXiv2017

Analysis of the $Λ_c(2860)$, $Λ_c(2880)$, $Ξ_c(3055)$ and $Ξ_c(3080)$ as D-wave baryon states with QCD sum rules

In this article, we tentatively assign the $Λ_c(2860)$, $Λ_c(2880)$, $Ξ_c(3055)$ and $Ξ_c(3080)$ to be the D-wave baryon states with the spin-parity $J^P={\frac{3}{2}}^+$, ${\frac{5}{2}}^+$, ${\frac{3}{2}}^+$ and ${\frac{5}{2}}^+$, respectively, and study their masses and pole residues with the QCD sum rules in a systematic way by constructing three-types interpolating currents with the quantum numbers $(L_ρ,L_λ)=(0,2)$, $(2,0)$ and $(1,1)$, respectively. The present predictions favor assigning the $Λ_c(2860)$, $Λ_c(2880)$, $Ξ_c(3055)$ and $Ξ_c(3080)$ to be the D-wave baryon states with the quantum numbers $(L_ρ,L_λ)=(0,2)$ and $J^P={\frac{3}{2}}^+$, ${\frac{5}{2}}^+$, ${\frac{3}{2}}^+$ and ${\frac{5}{2}}^+$, respectively. While the predictions for the masses of the $(L_ρ,L_λ)=(2,0)$ and $(1,1)$ D-wave $Λ_c$ and $Ξ_c$ states can be confronted to the experimental data in the future.

hep-ph↗

arXiv2017

Analysis of the scalar doubly charmed hexaquark state with QCD sum rules

In this article, we study the scalar-diquark-scalar-diquark-scalar-diquark type hexaquark state with the QCD sum rules by carrying out the operator product expansion up to the vacuum condensates of dimension 16. We obtain the lowest hexaquark mass $6.60^{+0.12}_{-0.09}\,\rm{GeV}$, which can be confronted to the experimental data in the future.

hep-ph↗

arXiv2017

Analysis of the mass and width of the $X^*(3860)$ with QCD sum rules

In this article, we tentatively assign the $X^*(3860)$ to be the $Cγ_5\otimes γ_5C$ type scalar tetraquark state, study its mass and width with the QCD sum rules, special attention is paid to calculating the hadronic coupling constants $G_{Xη_cπ}$ and $G_{XDD}$ concerning the tetraquark state. We obtain the values $M_{X}=3.86 \pm 0.09\,\rm{GeV}$ and $Γ_{X}= 202\pm 146 \,\rm{MeV}$, which are consistent with the experimental data. The numerical result supports assigning the $X^*(3860)$ to be the $Cγ_5\otimes γ_5C$ type scalar tetraquark state.

hep-ph↗

arXiv2017

On a problem of Bharanedhar and Ponnusamy involving planar harmonic mappings

In this paper, we give a negative answer to a problem presented by Bharanedhar and Ponnusamy (Rocky Mountain J. Math. 44: 753--777, 2014) concerning univalency of a class of harmonic mappings. More precisely, we show that for all values of the involved parameter, this class contains a non-univalent function. Moreover, several results on a new subclass of close-to-convex harmonic mappings, which is motivated by work of Ponnusamy and Sairam Kaliraj (Mediterr. J. Math. 12: 647--665, 2015), are obtained.

math.CV↗

arXiv2017

Analysis of the $QQ\bar{Q}\bar{Q}$ tetraquark states with QCD sum rules

In this article, we study the $J^{PC}=0^{++}$ and $2^{++}$ $QQ\bar{Q}\bar{Q}$ tetraquark states with the QCD sum rules, and obtain the predictions $M_{X(cc\bar{c}\bar{c},0^{++})} =5.99\pm0.08\,\rm{GeV}$, $M_{X(cc\bar{c}\bar{c},2^{++})} =6.09\pm0.08\,\rm{GeV}$, $M_{X(bb\bar{b}\bar{b},0^{++})} =18.84\pm0.09\,\rm{GeV}$ and $M_{X(bb\bar{b}\bar{b},2^{++})}=18.85\pm0.09\,\rm{GeV}$, which can be confronted to the experimental data in the future. Furthermore, we illustrate that the diquark-antidiquark type tetraquark state can be taken as a special superposition of a series of meson-meson pairs and embodies the net effects.

hep-ph↗

arXiv2017

Analysis of the $Ω_c(3000)$, $Ω_c(3050)$, $Ω_c(3066)$, $Ω_c(3090)$ and $Ω_c(3119)$ with QCD sum rules

In this article, we assign the $Ω_c(3000)$, $Ω_c(3050)$, $Ω_c(3066)$, $Ω_c(3090)$ and $Ω_c(3119)$ to be the P-wave baryon states with $J^P={\frac{1}{2}}^-$, ${\frac{1}{2}}^-$, ${\frac{3}{2}}^-$, ${\frac{3}{2}}^-$ and ${\frac{5}{2}}^-$, respectively, and study them with the QCD sum rules by introducing an explicit relative P-wave between the two $s$ quarks. The predictions support assigning the $Ω_c(3050)$, $Ω_c(3066)$, $Ω_c(3090)$ and $Ω_c(3119)$ to be the P-wave baryon states with $J^P={\frac{1}{2}}^-$, ${\frac{3}{2}}^-$, ${\frac{3}{2}}^-$ and ${\frac{5}{2}}^-$, respectively, where the two $s$ quarks are in relative P-wave; while the $Ω_c(3000)$ can be assigned to the P-wave baryon state with $J^{P}={\frac{1}{2}}^-$, where the two $s$ quarks are in relative S-wave.

hep-ph↗

arXiv2017

Analysis of the $Y(4220)$ and $Y(4390)$ as molecular states with QCD sum rules

In this article, we assign the $Y(4390)$ and $Y(4220)$ to be the vector molecular states $D\bar{D}_1(2420)$ and $D^*\bar{D}_0^*(2400)$, respectively, and study their masses and pole residues with the QCD sum rules in details. The present calculations only favor assigning the $Y(4390)$ to be the $D\bar{D}_1(1^{--})$ molecular state.

hep-ph↗

arXiv2017

On third Hankel determinants for subclasses of analytic functions and close-to-convex harmonic mappings

In this paper, we obtain the upper bounds to the third Hankel determinants for starlike functions of order $α$, convex functions of order $α$ and bounded turning functions of order $α$. Furthermore, several relevant results on a new subclass of close-to-convex harmonic mappings are obtained. Connections of the results presented here to those that can be found in the literature are also discussed.

math.CV↗

arXiv2017

Analysis of the mass and width of the $Y(4274)$ as axialvector molecule-like state

In this article, we assign the $Y(4274)$ to be the color octet-octet type axialvector molecule-like state with $J^{PC}=1^{++}$ tentatively, and construct the color octet-octet type axialvector current to study its mass and width with the QCD sum rules in details. The predicted mass favors assigning the $Y(4274)$ to be the color octet-octet type molecule-like state, but the predicted width disfavors assigning the $Y(4274)$ to be the color octet-octet type molecule-like state strongly. The $Y(4274)$ may be the conventional charmonium state $χ_{c1}(\rm 3P)$, and it is important to observe the decay $Y(4274)\to J/ψω$ to diagnose the nature of the $Y(4274)$.

hep-ph↗

arXiv2016

Reanalysis of the $X(3915)$, $X(4500)$ and $X(4700)$ with QCD sum rules

In this article, we study the $Cγ_5\otimes γ_5C$ type and $C\otimes C$ type scalar $cs\bar{c}\bar{s}$ tetraquark states with the QCD sum rules by calculating the contributions of the vacuum condensates up to dimension 10 in a consistent way. The ground state masses $M_{Cγ_5\otimes γ_5C}=3.89\pm 0.05\,\rm{GeV}$ and $M_{C\otimes C}=5.48\pm0.10\,\rm{GeV}$ support assigning the $X(3915)$ to be the ground state $Cγ_5\otimes γ_5C$ type tetraquark state with $J^{PC}=0^{++}$, but do not support assigning the $X(4700)$ to be the ground state $C\otimes C$ type $cs\bar{c}\bar{s}$ tetraquark state with $J^{PC}=0^{++}$. Then we tentatively assign the $X(3915)$ and $X(4500)$ to be the 1S and 2S $Cγ_5\otimes γ_5C$ type scalar $cs\bar{c}\bar{s}$ tetraquark states respectively, and obtain the 1S mass $M_{\rm 1S}=3.85^{+0.18}_{-0.17}\,\rm{GeV}$ and 2S mass $M_{\rm 2S}=4.35^{+0.10}_{-0.11}\,\rm{GeV}$ from the QCD sum rules, which support assigning the $X(3915)$ to be the 1S $Cγ_5\otimes γ_5C$ type tetraquark state, but do not support assigning the $X(4500)$ to be the 2S $Cγ_5\otimes γ_5C$ type tetraquark state.

hep-ph↗

arXiv2016

Reanalysis of the $X(4140)$ as axialvector tetraquark state with QCD sum rules

In this article, we take the $X(4140)$ as the diquark-antidiquark type $cs\bar{c}\bar{s}$ tetraquark state with $J^{PC}=1^{++}$, and study the mass and pole residue with the QCD sum rules in details by constructing two types interpolating currents. The numerical results $M_{X_{L,+}}=3.95\pm0.09\,\rm{GeV}$ and $M_{X_{H,+}}=5.00\pm0.10\,\rm{GeV}$ disfavor assigning the $X(4140)$ to be the $J^{PC}=1^{++}$ diquark-antidiquark type $cs\bar{c}\bar{s}$ tetraquark state. Moreover, we obtain the masses of the $J^{PC}=1^{+-}$ diquark-antidiquark type $cs\bar{c}\bar{s}$ tetraquark states as a byproduct. The present predictions can be confronted to the experimental data in the future.

hep-ph↗

arXiv2016

Analysis of the tensor-tensor type scalar tetraquark states with QCD sum rules

In this article, we study the ground states and the first radial excited states of the tensor-tensor type scalar hidden-charm tetraquark states with the QCD sum rules. We separate the ground state contributions from the first radial excited state contributions unambiguously, and obtain the QCD sum rules for the ground states and the first radial excited states, respectively. Then we search for the Borel parameters and continuum threshold parameters according to four criteria and obtain the masses of the tensor-tensor type scalar hidden-charm tetraquark states, which can be confronted to the experimental data in the future.

hep-ph↗

arXiv2016

Strong decays of the charmed mesons $D_1^(2680)$, $D^_3(2760)$, $D_2^*(3000)$

In this article, we assign the higher charmed mesons $D^*_1(2680)$, $D_3^*(2760)$ and $D_2^*(3000)$ to be the 2S $1^-$, 1D $3^-$ and 1F $2^+$ states, respectively, and study the two-body strong decays to the ground state charmed mesons and light pseudoscalar mesons with the heavy meson effective theory. We obtain the ratios among the strong decays, which can be confronted to the experimental data in the future and shed light on the nature of those higher charmed mesons.

hep-ph↗

arXiv2016

Analysis of the strong decays $D_{s3}^(2860)\to DK$, $D^{}K$ with QCD sum rules

In this article, we assign the $D_{s3}^*(2860)$ to be a D-wave $c\bar{s}$ meson, study the hadronic coupling constants $G_{D_{s3}^*(2860)DK}$ and $G_{D_{s3}^*(2860)D^*K}$ with the three-point QCD sum rules, and calculate the partial decay widths $Γ\left(D_{s3}^*(2860)\to D^{*}K\right)$ and $Γ\left(D_{s3}^*(2860)\to DK\right)$. The predicted ratio $R=Γ\left(D_{s3}^*(2860)\to D^{*}K\right)/Γ\left(D_{s3}^*(2860)\to DK\right)=0.57\pm0.38$ cannot reproduce the experimental value $R={\rm Br}\left(D_{sJ}^*(2860)\to D^{*}K\right)/{\rm Br}\left(D_{sJ}^*(2860)\to DK\right)=1.10 \pm 0.15 \pm 0.19$.

hep-ph↗

arXiv2016

Analysis of the ${\frac{3}{2}}^{\pm}$ pentaquark states in the diquark-diquark-antiquark model with QCD sum rules

In this article, we construct the axialvector-diquark-scalar-diquark-antiquark type and the axialvector-diquark-axialvector-diquark-antiquark type interpolating currents, and study the $J^P={\frac{3}{2}}^\pm$ hidden-charm pentaquark states with the strangeness $S=0,\,-1,\,-2,\,-3$ systematically using the QCD sum rules. The predicted masses of the pentaquark states $P_{uud}^{10\frac{1}{2}}\left({\frac{3}{2}^-}\right)$, $P_{uud}^{11\frac{1}{2}}\left({\frac{3}{2}^-}\right)$ and $P_{uud}^{11\frac{3}{2}}\left({\frac{3}{2}^-}\right)$ are compatible with the experimental value $M_{P_c(4380)}=4380\pm 8\pm 29\,\rm{MeV}$ from the LHCb collaboration, more experimental data are still needed to identify the $P_c(4380)$ unambiguously.

hep-ph↗

arXiv2016

Analysis of the $D_{s3}^*(2860)$ as a D-wave $c\bar{s}$ meson with QCD sum rules

In this article, we assign the $D_{s3}^*(2860)$ to be a D-wave $c\bar{s}$ meson, and study the mass and decay constant of the $D_{s3}^*(2860)$ with the QCD sum rules by calculating the contributions of the vacuum condensates up to dimension-6 in the operator product expansion. The predicted mass $M_{D_{s3}^*}=(2.86\pm0.10)\,\rm{GeV}$ is in excellent agreement with the experimental value $M_{D_{s3}^*}=(2860.5\pm 2.6 \pm 2.5\pm 6.0)\,\rm{ MeV}$ from the LHCb collaboration. The present prediction supports assigning the $D_{s3}^*(2860)$ to be the D-wave $c\bar{s}$ meson.

hep-ph↗

arXiv2016

Analysis of the $X(5568)$ as scalar tetraquark state in the diquark-antidiquark model with QCD sum rules

In this article, we take the $X(5568)$ as the diquark-antidiquark type tetraquark state with the spin-parity $J^P=0^+$, construct the scalar-diquark-scalar-antidiquark type current, carry out the operator product expansion up to the vacuum condensates of dimension-10, and study the mass and pole residue in details with the QCD sum rules. We obtain the value $M_X=\left(5.57\pm0.12 \right) \,\rm{GeV}$, which is consistent with the experimental data. The present prediction favors assigning the $X(5568)$ to be the scalar tetraquark state.

hep-ph↗

arXiv2016

Analysis of the scalar nonet mesons with the QCD sum rules

In this article, we assume that the nonet scalar mesons below $1\,\rm{ GeV}$ are the two-quark-tetraquark mixed states and study their masses and pole residues using the QCD sum rules. In calculation, we take into account the vacuum condensates up to dimension 10 and the $\mathcal{O}(α_s)$ corrections to the perturbative terms in the operator product expansion. We determine the mixing angles, which indicate the two-quark components are much larger than $50\%$, then obtain the masses and pole residues of the nonet scalar mesons.

hep-ph↗