Analysis of the decay B^0→χc1~π~0 with light-cone QCD sum rules

In this article, we calculate the contribution from the nonfactorizable soft hadronic matrix element to the decay B^0→Xc1π^0 with the light-cone quantum chromo-dynamic （QCD） sum rules. The numerical results show that its contribution is rather large and should not be neglected. The total amplitudes lead to a branching fraction which is in agreement with the experimental data marginally.

Analysis of Scalar Doubly Heavy Tetraquark States with QCD Sum Rules

在这篇文章，我们二倍地执行数量的集体光谱的详细研究 charmed 并且二倍地，用 QCD 的底部 tetraquark 状态加规则。

Fermion Corrections to Mass of Scalar Glueball in QCD Sum Rule

Contributions of fermions to the mass of the scalar glueball 0++are calculated at two-loop level in theframework of QCD sum rules.It slightly changes the coefficients in the operator product expansion （OPE） and shiftsthe mass of glueball to 1.72 ± 0.07 GeV.

A Comparative Study of f_B within QCD Sum Rules with Two Typical Correlators up to Next-to-Leading Order

B 介子腐烂常数 fB 是为学习 B 介子腐烂的一个重要部件，它能通过 QCD 和规则被学习。我们用二条和规则在 fB 上做详细讨论直到 next-to-leading 顺序，即和规则我和 II，它分别地与 chiral 水流从常规相关因子和相关因子被导出。这二条和规则与对方一致，这被发现。和规则 II 作为和规则的包含更少的 non-perturbative 冷凝物我，并且原则上，如果我们知道尺寸，它能是更精确的 -- 四 gluon 冷凝物很好。fB 与 mb 的增长减少，这被发现，并且在 fB 上与美人试验性的数据作比较，两个都，和裁定我和 II 比较喜欢更小的杆 b 夸克质量， mb = 4.68 湉琠楨? 慰数 ? 愠 ? 湩楦楮整猠煥敵据 ? 景挠湯敳癲瑡潩 ? 慬獷映牯愠朠湥牥污穩摥瘠牡慩汢? 潣晥楦楣湥 ? 楦瑦 ? 牯敤 ? 潋瑲睥来搭 ? 牖敩 ? 煥慵楴湯椠 ? 汦極獤愠敲挠湯瑳畲瑣摥戠獡摥漠 ? 桴 ?? 正畬摮琠慲獮潦浲瑡潩吗？

{Q}{^(('))s}Molecular States in QCD Sum Rules

We systematically investigate the mass spectra of {Q}{^(('))s} molecular states in the framework of QCDsum rules.The interpolating currents representing the molecular states are proposed.Technically, contributions of theoperators up to dimension six are included in operator product expansion (OPE).The masses for molecular states withvarious {Q}{^(('))s} configurations are presented.The result 4.36±0.08 GeV for the D_s~*_(s0)~* molecular state is consistentwith the mass 4350_(-5.1)^(+4.6)±0.7 MeV of the newly observed X(4350), which could support X(4350) interpreted as a D_s~*_(s0)~*molecular state.

Analysis of Y(4660) and Related Bound States with QCD Sum Rules

In this article,we take the vector charmonium-like state Y(4660) as a Ψ'f_0(980) bound state (irrespective ofthe hadro-charmonium and the molecular state) tentatively,and study its mass using the QCD sum rules.The numericalvalue M_Y = 4.71±0.26 GeV is consistent with the experimental data.Considering the SU(3) symmetry of the light flavorquarks and the heavy quark symmetry,we also study the bound states Ψ′σ(400-1200),γ′″ f_0(980),and γ′″σ(400-1200)with the QCD sum rules,and make reasonable predictions for their masses.

Reanalyzing Pentaquark Θ^＋（1540） in Framework of QCD Sum Rules Approach with Direct Instantons

在这篇文章，我们学习 pentaquark 状态Θ ~+(1540 ) 与一(数量) 在 QCD 和的框架的 diquark 反夸克类型插入内推电流统治的 diquark-( 假数量) 由从直接立刻的 ons 包括贡献的途径。数字结果显示从直接立刻的 ons 的贡献是很小的并且能安全地被忽视。

Nuclear symmetry energy from QCD sum rules

We calculated the nucleon self-energies in iso-spin asymmetric nuclear matter and obtained the nuclear symmetry energy by taking difference of these of neutron and proton.We find that the scalar(vector) self-energy part gives a negative(positive) contribution to the nuclear symmetry energy,consistent with the result from relativistic mean-field theories.Also,we found exact four-quark operator product expansion for nucleon sum rule.Among them,twist-4 matrix elements which can be extracted from deep inelastic scattering experiment constitute an essential part in the origin of the nuclear symmetry energy from QCD.Our result also extends early success of QCD sum rule in the symmetric nuclear matter to the asymmetric nuclear matter.

Strong decay of Y(4230)→ J/ψ f0(980) in light cone sum rules

In this study,we assign the tetraquark state for the Y(4230) resonance and investigate the mass and decay constant of Y(4230) in the framework of SVZ sum rules through a different calculation technique.Then,we calculate the strong coupling gYJ/ψf0 by considering soft-meson approximation techniques within the framework of light cone sum rules,and we use the strong coupling gYJ/ψf0 to obtain the width of the decay Y(4230)→J/ψf0(980).Our prediction for the mass agrees with the experimental measurement,and that for the decay width of Y(4230)→J/ψf0(980) is within the upper limit.

QCD sum rule study of J^(P)=1^(±)exotic states with two heavy quarks in the molecular picture

In this study,the spectroscopic parameters of exotic molecular states composed of mesons containing two heavy quarks(scalar-axial and pseudoscalar-axial meson combinations)are investigated within the QCD sum rules.Our findings reveal that molecular states containing charm quarks do not form bound states,whereas states with b-quarks can form exotic molecular states.This observation has significant implications for understanding the structure of these exotic states.

Strong decays of the P_(c)(4312) and its isospin cousin via the QCD sum rules

In this study,considering the conservation of isospin in the strong decays,we investigate the strong decays of the pentaquark molecule candidate P_(c)(4312)and its possible higher isospin cousin P_(c)(4330)in the framework of the QCD sum rules.Further,the pole residue of theΔbaryon with isospin eigenstate|II3>=|3/21/2)is obtained.If the possible pentaquark molecule candidate P_(c)(4330)could be determined,it would shed light on the interpretations of the P_(c) states in future experiments.

Fully-light vector tetraquark states with explicit P-wave via QCD sum rules

In this study,we apply the QCD sum rules to investigate the vector fully-light tetraquark states with an explicit P-wave between the diquark and antidiquark pairs.We observed that the Cγα⊗↔∂μ⊗γαC(or Cγα⊗↔Dμ⊗γαC)type current with fully-strange quarks couples potentially to a tetraquark state with a mass 2.16±0.14GeV,which supports assigning Y(2175)/ϕ(2170)as the diquark-antidiquark type tetraquark state with JPC=1−−.The qsˉqˉs and ssˉsˉs vector tetraquark states with the structure Cγμ⊗↔∂α⊗γαC+Cγα⊗↔∂α⊗γμ(or Cγμ⊗↔Dα⊗γαC+Cγα⊗↔Dα⊗γμ)are consistent with X(2200)and X(2400),respectively,which lie in the region from 2.20 to 2.40GeV.The central values of the masses of the fully-strange vector tetraquark states with an explicit P-wave are approximately 2.16−3.13GeV(or 2.16−3.16GeV).Predictions for other fully-light vector tetraquark states with and without hidden-strange are also presented.

The Λ-type P-wave bottom baryon states via the QCD sum rules

Our study focuses on the Λ-type P-wave bottom baryon states with spin-parity JP=1/2−, 3/2−. We introduce an explicit P-wave between the two light quarks in the interpolating currents (these light quarks are antisymmetric in the flavor space, thus giving rise to the designation of Λ-type baryon) to investigate the Λb and Ξ_(b) states within the framework of the full QCD sum rules. The predicted masses show that Ξ_(b)(6087) and Ξ_(b)(6095/6100) could be the P-wave bottom-strange baryon states with spin-parity JP=1/2− and 3/2−, respectively;meanwhile, Λb(5912) and Λb(5920) could be the P-wave bottom baryon states with spin-parity JP=1/2− and 3/2−, respectively. Moreover, Λb(5920) and Ξ_(b)(6095/6100) may have two remarkable under-structures or Fock components at least.

Constraints ofξ-moments computed using QCD sum rules on pion distribution amplitude models

To date,the behavior of the pionic leading-twist distribution amplitude(DA)φ2;π(x,μ)-which is a universal physical quantity and is introduced into high-energy processes involving pions based on the factorization theorem-is not completely consistent.The form ofφ2;π(x,μ)is usually described by phenomenological models and constrained by the experimental data on exclusive processes containing pions or the moments computed using QCD sum rules and the lattice QCD theory.Evidently,an appropriate model is extremely important to determine the exact behavior ofφ2;π(x,μ).In this paper,by adopting the least squares method to fit theξ-moments calculated using QCD sum rules based on the background field theory,we perform an analysis on several commonly used models of the pionic leading-twist DA in the literature;these include the truncation form of the Gegenbauer polynomial series,the light-cone harmonic oscillator model,the form extracted from the Dyson-Schwinger equations,the model from the light-front holographic AdS/QCD,and a simple power-law parametrization form.

QCD sum rule study for hidden-strange pentaquarks

Inspired by the LHCb observations of hidden-charm Pc(s)states,we study their hidden-strange analog Psstates in both the[udu][■s]and[uds][■u]configurations.We investigate Ps pentaquark states in the pη′,pφ,ΛK,ΣK,andΣ*K*structures with JP=1/2-andΣ*K andΣK*with JP=3/2-and calculate their masses in the framework of QCD sum rules.Our numerical results show that the extracted hadron masses for all the pη′,pφ,ΛK,ΣK,andΣ*K*structures are significantly higher than theΣK mass threshold,and the masses forΣ*K andΣK*are also higher than the threshold of the corresponding hadron;hence,no bound state exists in such channels,which is consistent with the current experimental status.

Analysis of Pcs(4338) and related pentaquark molecular states via QCD sum rules

In this study,we tentatively identify Pcs(4338)■Ξc molecular state and distinguish the isospins of current operators to explore in detail the■Ξc,■Λc,■sΞc,■sΛc,■*Ξc,■*Λc,■*sΞc,and■*sΛcmolecular states without strange,with strange,and with double strange in the framework of QCD sum rules.The present exploration favors identifying Pcs(4338)(Pcs(4459))as the■Ξc(■*Ξc)molecular state with the spin-parity JP=1/2-(3/2-)and(I,I3)=(0,0),and the observation of their cousins with the isospin(I,I3)=(1,0)J/ψΣ0/ηcΣ0in the invariant mass distributions would decipher their inner structures.

NaI (Tl) calorimeter calibration and simulation for Coulomb sum rule experiment in Hall-A at Jefferson Lab

A precision measurment of inclusive electron scattering cross sections is carried out at Jefferson Lab in the quasi-elastic region for 4 He, 12 C, 56 Fe and 208 Pb targets. The longitudinal （R L ） and transverse （R T ） response functions of the nucleon need to be extracted precisely in the momentum transfer range 0.55 GeV/c≤ ｜ q ｜ ≤1.0 GeV/c. To achieve the above goal, a NaI （Tl） calorimeter is used to distinguish good electrons from background, including pions and low energy electrons rescattered from the walls of the spectrometer magnets. Due to a large set of kinematics and changes in HV settings, a number of calibrations are performed for the NaI （Tl） detector. Corrections for a few blocks of NaI （Tl） with bad or no signal are applied. The resolution of the NaI （Tl） detector after calibration reached δE/E^（1/2） ≈ 3% at E=1 GeV. The performance of the NaI （Tl） detector is compared with a simulation. The good calibration and background analysis for the NaI（Tl） detector are very important for the reduction of the systematic error of cross sections and the separation of R L and R T .

Study of spin sum rules (and the strong coupling constant at large distances)

We present recent results from Jefferson Lab on sum rules related to the spin structure of the nucleon. We then discuss how the Bjorken sum rule with its connection to the Gerasimov-Drell-Hearn sum, allows us to conveniently define an effective coupling for the strong force at all distances.

Radiation and ionization energy loss simulation for the GDH sum rule experiment in Hall-A at Jefferson Lab

The radiation and ionization energy loss are presented for single arm Monte Carlo simulation for the GDH sum rule experiment in Hall-A at the Jefferson Lab. Radiation and ionization energy loss are discussed for12 C elastic scattering simulation. The relative momentum ratio△p pand12 C elastic cross section are compared without and with radiative energy loss and a reasonable shape is obtained by the simulation. The total energy loss distribution is obtained, showing a Landau shape for12 C elastic scattering. This simulation work will give good support for radiation correction analysis of the GDH sum rule experiment.

Heavy flavor baryon spectra via QCD sum rules

In this talk, we give a short review of our recent works on studying the singly heavy baryon, doubly heavy baryon, and triply heavy baryon Spectra from QCD sum rules.