123075504
Analysis of the heavy quarkonium states hc and hb with QCD sum rules
In this article, we take the tensor currents to interpolate the P-wave spin-singlet heavy quarkonium states hQ, and study the masses and decay constants with the Borel sum rules and moments sum rules. The masses and decay constants from the Borel sum rules and moments sum rules are consistent with each other, the masses are also consistent with the experimental data. The heavy quarkonium states hQ couple potentially to the tensor currents , and have the quark structure ϵijkξ†σkζ besides the quark structure .
119121085
ANALYSIS OF THE $B \to K^*_2(1430), a_2(1320), f_2(1270)$ FORM-FACTORS WITH LIGHT-CONE QCD SUM RULES
In this paper, we study the form-factors with the light-cone QCD sum rules, where the B-meson light-cone distribution amplitudes are used. In calculations, we observe that the line-shapes of the B-meson light-cone distribution amplitude ϕ+(ω) have significant impacts on the values of the form-factors, and expect to obtain severe constraints on the parameters of the B-meson light-cone distribution amplitudes from the experimental data in the future.
118179000
Magnetic moment of the pentaquark state $\Theta^+(1540)$
In this article, we study the magnetic moment of the pentaquark $ \Theta^+(1540)$ as (scalar)diquark-(pseudoscalar)diquark-antiquark state with the QCD sum rules approach in the external electromagnetic field. Due to the special structure of the interpolating current, only the electromagnetic interactions of the $s$ quark with the external field have contributions to the magnetic moment with tensor structure $\{\sigma_{\mu\nu} {\hat p} +{\hat p}\sigma_{\mu\nu}\}$. The numerical results indicate the magnetic moment of the pentaquark state $ \Theta^+(1540)$ is about $\mu_{\Theta^+}=(0.16\pm0.03)\mu_N$.
118430852
Analysis of mass difference of the $\pi$ and $\rho$ with Bethe-Salpeter equation
In this article, we take into account the one-pion exchange force besides the onegluon exchange force to study the mass difference of the π and ρ mesons with the Bethe-Salpeter equation. After projecting the Bethe-Salpeter equation into an simple form, we can see explicitly that the bound energy |Eπ| ≫ |Eρ|. PACS number: 12.39.Ki, 12.39.Pn
15122700
Analysis of the Y(2175) as a tetraquark state with QCD sum rules
Abstract In this article, we take the point of view that Y ( 2175 ) be a tetraquark state which consists of color octet constituents, and calculate its mass and decay constant within the framework of the QCD sum rule approach. We release standard criterion in the QCD sum rules approach and take more phenomenological analysis, the value of the mass of Y ( 2175 ) is consistent with experimental data; there may be some tetraquark components in the state Y ( 2175 ) . If we retain standard criterion, larger mass than experimental data can be obtained, the current J μ ( x ) can interpolate a tetraquark state with larger mass, or Y ( 2175 ) has some components with larger mass. The dominating contribution comes from the perturbative term, which is in contrast to the sum rules with interpolating currents constructed from diquark pairs. The tetraquark states may consist of color octet constituents rather than diquark pairs.
119252067
Next-to-leading Order Perturbative Contributions in the QCD Sum Rules for Mesonic Two-point Correlation Functions with Unequal Quark Masses
In this article, we assume that the two quarks have unequal masses and calculate the next-to-leading order contributions to the spectral densities of the mesonic two-point correlation functions of the vector, axialvector, scalar and pseudoscalar currents. We take dimensional regularization to regularize both the ultraviolet and infrared divergences, and use optical theorem to obtain the spectral densities directly, furthermore, we present some necessary technical details for readers convenience. The analytical expressions are applicable in many phenomenological analysis besides the QCD sum rules.
45104645
Solvent-induced DNA conformational transition.
Modified water models with scaled charges are used to investigate solvent polarity effects on DNA structure. Several intensive molecular dynamics simulations of the DNA EcoRI dodecamer d(CGCGAATTCGCG) in different model solvents are performed. When the polarity of the solvent molecule decreases, from overpolarized to less polarized, DNA experiences the conformational transitions of constrained-->B form-->(A-B)mix-->A form. We demonstrate that one important cause of these structure changes is the competition between hydration and direct cation coupling to the free oxygen atoms in the phosphate groups on DNA backbones.
119458784
An Analysis of the X-Ray Emission from the Supernova Remnant 3C 397
The ASCA SIS and ROSAT PSPC spectral data of the supernova remnant 3C 397 are analyzed with a two-component nonequilibrium ionization model. In addition, the ASCA SIS0 and SIS1 spectra are fitted simultaneously in an equilibrium case. The resulting values of the hydrogen column density yield a distance of ~8 kpc to 3C 397. It is found that the hard X-ray emission, containing S and Fe Kα lines, arises primarily from the hot component, while most of the soft emission, composed mainly of Mg, Si, and Fe L lines and continuum, is produced by the cool component. The emission measures suggest that the remnant evolves in a cloudy medium and imply that the supernova progenitor might not be a massive early-type star. The cool component is approaching ionization equilibrium. The ages estimated from the ionization parameters and dynamics are all much greater than the previous determination. We restore the X-ray maps using the ASCA SIS data and compare them with the ROSAT HRI and the NRAO VLA Sky Survey 20 cm maps. The morphology with two bright concentrations suggests a bipolar remnant encountering a denser medium in the west.
122786546
Field equations, conservation laws in 2D quantum gravity and the Beltrami-KdV-Liouville system
Abstract We present the equations of motion and the conservation laws under various gauges of 2D induced gravity as a kind of the Beltrami-Liouville theory. We generalize the schwarzian derivative and derive its composition law. We also find the relation between the Beltrami-Liouville theory and the KdV system as well as the reccursion relations due to Gel'fand and Dikii based on the properties of the quasiconformal transformations.
121193140
Dynamical symmetry breaking, confinement with flat-bottom potential
Abstract In this Letter, we calculate the dressed quark propagator with the flat bottom potential in the framework of the rainbow Schwinger–Dyson equation. Then based on the nonperturbative dressed quark propagator, we calculate the  π decay constant and the quark condensate. The  π decay constant is an important parameter in describing the interplay between dynamical symmetry breaking and confinement, while the quark condensate is an order parameter for dynamical chiral symmetry breaking. To implement confinement, we prove that the dressed quark propagator has no poles on the real timelike p 2 axial, the absence of Kallen–Lehmann spectral representation obviously precludes the existence of free quarks.
279557
Topological quantum phase transitions and edge states in spin-orbital coupled Fermi gases
We study superconducting states in the presence of spin-orbital coupling and Zeeman field. It is found that a phase transition from a Fulde-Ferrell-Larkin-Ovchinnikov state to the topological superconducting state occurs upon increasing the spin-orbital coupling. The nature of this topological phase transition and its critical property are investigated numerically. Physical properties of the topological superconducting phase are also explored. Moreover, the local density of states is calculated, through which the topological feature may be tested experimentally.