arXiv subjects

Ming-Qiu Huang

Publications and source records attributed to Ming-Qiu Huang.

At least 37 records · Page 2Linked to original sources

arXiv2014

Could $Z_{c}(4025)$ be a $J^{P}=1^{+}$ $D^{}\bar{D^{}}$ molecular state?

We investigate whether the newly observed narrow resonance $Z_{c}(4025)$ can be described as a $D^{*}\bar{D^{*}}$ molecular state with quantum numbers $J^{P}=1^{+}$. Using QCD sum rules, we consider contributions up to dimension six in the operator product expansion and work at leading order of $α_{s}$. The mass obtained for this state is $(4.05\pm 0.28) \mbox{GeV}$. It is concluded that $D^{*}\bar{D^{*}}$ molecular state is a possible candidate for $Z_{c}(4025)$.

hep-ph↗

arXiv2014

Higher Order Corrections to the Light-cone Distribution Amplitudes of the Sigma baryon

The Light-cone distribution amplitudes (LCDAs) of the $Σ^\pm$ baryons up to twist six are investigated on the basis of QCD conformal partial wave expansion approach. The calculations are carried out to the next-to-leading order of conformal spin accuracy. The nonperturbative parameters relevant to the LCDAs are determined in the framework of the QCD sum rule method. The explicit expressions of the LCDAs are given as the main results.

hep-ph↗

arXiv2013

$η_{b}BB^{\ast}$ vertex from QCD sum rules

The form factor and the coupling constant in the $η_{b}BB^{\ast}$ vertex are evaluated in the framework of three-point QCD sum rules. The correlation functions responsible for the vertex is evaluated considering contributions of both $B$ and $B^{\ast}$ mesons as off-shell states. The form factors obtained are different for the two cases, whereas the final results of the coupling constant are compatible.

hep-ph↗

arXiv2012

Improved Light-cone QCD Sum Rule Analysis Of The Rare Decays $Λ_b\rightarrowΛγ$ And $Λ_b\rightarrowΛl^+l^-$

We present a systematic light-cone QCD sum rule study of the exclusive rare radiative decay $Λ_b\rightarrowΛγ$ and rare semileptonic decay $Λ_b\rightarrowΛl^+l^-$ within the framework of the standard model. Although some LCSR studies on these rare processes can be found in different literatures, it is necessary to reanalyze them systematically for the reason that either the baryonic distribution amplitudes are improved or different interpolating currents for the $Λ_b$ baryon may lead to quite different results. In addition, the rare process $Λ_b\rightarrowΛγ$ has not yet been analyzed by LCSR with the Ioffe-type current. Taking all these reasons into account, we perform LCSR calculations of both the processes with two types of interpolating currents. Our calculations show that the choice of the interpolating current for the $Λ_b$ baryon can affect the predictions significantly, especially for the rare radiative decay process.

hep-ph↗

arXiv2012

Search for $Z^{+}_{s1}$ and $Z^{+}_{s2}$ strangeonium-like structures

Theoretically, it has been presumed from an effective Lagrangian calculation that there could exist two charged strangeonium-like molecular states $Z^{+}_{s1}$ and $Z^{+}_{s2}$, with $K\bar{K}^{*}$ and $K^{*}\bar{K}^{*}$ configurations respectively. In the framework of QCD sum rules, we predict that masses of $Z^{+}_{s1}$ ($K\bar{K}^{*}$) and $Z^{+}_{s2}$ ($K^{*}\bar{K}^{*}$) are $1.85\pm0.14 GeV$ and $2.02\pm0.15 GeV$ respectively, which are both above their respective two meson thresholds. We suggest to put in practice the search for these two charged strangeonium-like structures in future experiments.

hep-ph↗

arXiv2012

Can X(3872) be a $J^{P}=2^{-}$ tetraquark state?

In this article, we test the nature of X(3872), which is assumed to be a P-wave $[cq]$-scalar-diquark $[\bar{c}\bar{q}]$-axial-vector-antidiquark tetraquark state with $J^{P}=2^{-}$. The interpolating current representing the $J^{P}=2^{-}$ state is proposed. Technically, contributions of the operators up to dimension six are included in the operator product expansion (OPE). The mass obtained for such state is $m_{2^{-}}=(4.38\pm 0.15) GeV$. We conclude that it is impossible to describe the X(3872) structure as $J^{P}=2^{-}$ tetraquark state.

hep-ph↗

arXiv2012

$B^{\ast}_{s1}B^{\ast}K$ form factor from QCD sum rules

In this article, we calculate the form factors and the coupling constant of the $g_{B^{\ast}_{s1}B^{\ast} K}$ vertex in the framework of the three-point QCD sum rules. Three point correlation functions responsible for the vertex are evaluated by considering both $B^{\ast}$ and $K$ mesons as off-shell states. The form factors obtained are different if the $B^{\ast}$ or the $K$ meson is off-shell but give the same coupling constant.

hep-ph↗

arXiv2012

$B^{\ast}B^{\ast}ρ$ vertex from QCD sum rules

The form factors and the coupling constants in the $B^{\ast}B^{\ast}ρ$ vertex are evaluated in the framework of three-point QCD sum rules. The correlation functions responsible for the form factors are evaluated considering contributions of both $B^{\ast}$ and $ρ$ mesons as off-shell states. The obtained numerical results for the coupling constants are in agreement with light-cone QCD sum rules calculations.

hep-ph↗

arXiv2012

Investigating different structures of the Z_{b}(10610) and Z_{b}(10650)

The recently observed narrow resonance $Z_{b}(10610)$ is examined with the assumptions both as a $B^{*}\bar{B}$ molecular state and a $[bd][\bar{b}\bar{u}]$ tetraquark state with quantum numbers $I^{G}J^{P}=1^{+}1^{+}$. Possible interpolating currents are constructed to describe the $Z_{b}(10650)$ as an axial-vector $B^{*}\bar{B}^{*}$ molecular state or a $[bd][\bar{b}\bar{u}]$ tetraquark state. Using QCD sum rules (QCDSR), we consider contributions up to dimension six in the operator product expansion (OPE) at the leading order in $α_{s}$. The mass is obtained as $(10.44\pm0.23) GeV$ for molecular state and $(10.50\pm0.19) GeV$ for tetraquark state, both of which coincide with the $Z_{b}(10610)$. The results $m_{B^{*}\bar{B}^{*}}=(10.45\pm0.31) GeV$ and $m_{[bd][\bar{b}\bar{u}]}=(10.48\pm0.33) GeV$ are consistent with the $Z_{b}(10650)$.

hep-ph↗

arXiv2011

Semileptonic Decays of $B^{**}_{s}$ mesons into $D_{s1}$ and $D^{*}_{s2}$ in HQET

In the framework of the heavy quark effective theory, the leading order Isgur-Wise functions relevant to semileptonic decays of the orbitally $P$-wave excited $B_{s}$ meson states $B^{**}_{s}$, including the newly found narrow $B_{s1}(5830)$ and $B^{*}_{s2}(5840)$ states, into the ($D_{s1}(2536)$, $D^{*}_{s2}(2573)$) doublet are calculated from QCD sum rules. With these universal form factors, the decay rates and branching ratios are also estimated.

hep-ph↗

arXiv2011

Could $Z_{b}(10610)$ be a $B^{*}\bar{B}$ molecular state?

Assuming the newly observed structure $Z_{b}(10610)$ as a bottomonium-like molecular state $B^{*}\bar{B}$, we calculate its mass in the framework of QCD sum rules. The numerical result is $10.54\pm0.22 GeV$ for $B^{*}\bar{B}$, which coincide with the mass of $Z_{b}(10610)$. This consolidates the statement made by Belle Collaboration that the $Z_{b}(10610)$ resonance could be a $B^{*}\bar{B}$ molecular state.

hep-ph↗

arXiv2011

Dynamical fermion mass generation and exciton spectra in graphene

The Coulomb interaction between massless Dirac fermions may induce dynamical chiral symmetry breaking by forming excitonic pairs in clean graphene, leading to semimetal-insulator transition. If the Dirac fermions have zero bare mass, an exact continuous chiral symmetry is dynamically broken and thus there are massless Goldstone excitons. If the Dirac fermions have a small bare mass, an approximate continuous chiral symmetry is dynamically broken and the resultant Goldstone type excitons become massive, which is analogous to what happens in QCD. In this paper, after solving Dyson-Schwinger gap equation in the presence of a small bare fermion mass, we found a remarkable reduction of the critical Coulomb interaction strength for excitonic pair formation and a strong enhancement of dynamical fermion mass. We then calculate the masses of Goldstone type excitons using the SVZ sum rule method and operator product expansion technique developed in QCD and find that the exciton masses are much larger than bare fermion mass but smaller than dynamical fermion mass gap. We also study the spin susceptibilities and estimate the masses of non-Goldstone type excitons using the same tools.

cond-mat.str-el↗

arXiv2011

The $P$-wave $[cs][\bar{c}\bar{s}]$ tetraquark state: Y(4260) or Y(4660)?

The mass of $P$-wave $cs$-scalar-diquark $\bar{c}\bar{s}$-scalar-antidiquark state is computed in the framework of QCD sum rules. The result $4.69\pm0.36{GeV}$ is in good agreement with the experimental value of Y(4660) but higher than Y(4260)'s, which supports the $P$-wave $[cs][\bar{c}\bar{s}]$ configuration for Y(4660) while disfavors the interpretation of Y(4260) as the $P$-wave $[cs][\bar{c}\bar{s}]$ state. In the same picture, the mass of $P$-wave $[bs][\bar{b}\bar{s}]$ is predicted to be $11.19\pm0.49 {GeV}$.

hep-ph↗

arXiv2010

$\{Q\bar{s}\}\{\bar{Q}^{(')}s\}$ molecular states in QCD sum rules

We systematically investigate the mass spectra of $\{Q\bar{s}\}\{\bar{Q}^{(')}s\}$ molecular states in the framework of QCD sum rules. The interpolating currents representing the molecular states are proposed. Technically, contributions of the operators up to dimension six are included in operator product expansion (OPE). The masses for molecular states with various $\{Q\bar{s}\}\{\bar{Q}^{(')}s\}$ configurations are presented. The result $4.36\pm0.08 GeV$ for the $D_{s}^{*}\bar{D}_{s0}^{*}$ molecular state is consistent with the mass $4350^{+4.6}_{-5.1}\pm0.7 MeV$ of the newly observed $X(4350)$, which could support $X(4350)$ interpreted as a $D_{s}^{*}\bar{D}_{s0}^{*}$ molecular state.

hep-ph↗

arXiv2010

Could $Y_{b}(10890)$ be the P-wave $[bq][\bar{b}\bar{q}]$ tetraquark state?

Assuming $Y_{b}(10890)$ as a P-wave $bq$-scalar-diquark $\bar{b}\bar{q}$-scalar-antidiquark tetraquark state, the mass of $Y_{b}(10890)$ is computed in the framework of QCD sum rule method. Technically, contributions of operators up to dimension six are included in the operator product expansion (OPE). The numerical result $10.88\pm0.13 GeV$ for $Y_{b}(10890)$ agrees well with the experimental value, which favors the P-wave $[bq][\bar{b}\bar{q}]$ tetraquark configuration for $Y_{b}(10890)$. In the same picture, the mass of $Y(4360)$ is calculated and the result $4.32\pm0.20 GeV$ is compatible with the experimental data, which supports $Y(4360)$'s P-wave $[cq][\bar{c}\bar{q}]$ structure.

hep-ph↗

arXiv2010

QCD Sum Rule Analysis of Semileptonic $B_{s1}$, $B^{}_{s2}$, $B^{}_{s0}$, and $B'_{s1}$ Decays in HQET

We present an analysis of semileptonic decays of orbitally, $P$-wave excited $B_{s}$ meson states $B^{**}_{s}$, including the newly found narrow $B_{s1}(5830)$ and $B^{*}_{s2}(5840)$ states, into low lying $D_{s}$ mesons ($D_{s}(1968)$, $D^{*}_{s}(2112)$, $D_{sJ}(2317)$, $D_{sJ}(2460)$) within the framework of heavy quark effective theory. The relevant universal form factors are estimated using QCD sum rules at the leading-order of the heavy quark expansion. The decay widths are predicted and the branching ratios are estimated.

hep-ph↗

arXiv2009

Improved analysis on the semi-leptonic decay $Λ_c\toΛ\ell^+ν$ from QCD light-cone sum rules

With the renewed distribution amplitudes of $Λ$, we present a reanalysis on the semi-leptonic decay $Λ_c\toΛ\ell^+ν$ by use of the light-cone sum rule approach with two kinds of interpolating currents. The form factors describing the decay process are obtained and used to predict the decay width. With the inclusion of up to twist-6 contributions the calculations give the decay width $Γ=(10.04\pm0.88)\times10^{-14}{GeV}$ for Chernyak-Zhitnitsky-type(CZ-type) current and $Γ=(6.45\pm1.06)\times10^{-14}{GeV}$ for Ioffe-type current. The Ioffe-type interpolating current is found to be better for the estimation of the decay rate from a comparison with experimental data.

hep-ph↗

arXiv2009

$\{Q\bar{q}\}\{\bar{Q}^{(')}q\}$ molecular states

Masses for $\{Q\bar{q}\}\{\bar{Q}^{(')}q\}$ molecular states are systematically studied in QCD sum rules. The interpolating currents representing the related molecular states are proposed. Technically, contributions of the operators up to dimension six are included in operator product expansion (OPE). Mass spectra for molecular states with $\{Q\bar{q}\}\{\bar{Q}^{(')}q\}$ configurations are obtained.

hep-ph↗