Quasiparticles as composite objects in the RVB superconductor

We study the nature of the superconducting state, the origin of d-wave pairing, and elementary excitations of a resonating valence bond (RVB) superconductor. We show that the phase string formulation of the t-J model leads to confinement of bare spinon and holon excitations in the superconducting state, though the vacuum is described by the RVB state. Nodal quasiparticles are obtained as composite excitations of spinon and holon excitations. The d-wave pairing symmetry is shown to arise from short range antiferromagnetic correlations

Possible S-wave Dibaryons in SU(3) Chiral Quark Model

In the framework of the SU(3) chiral quark model, the $S-$wave baryon-baryon bound states are investigated. It is found that according to the symmetry character of the system and the contributions from chiral fields, there are three types of bound states. The states of the first type, such as $[\Omega\Omega]_{(0,0)}$ and $[\Xi^{*}\Omega]_{(0,1/2)}$ are deeply bound dibaryon with narrow widths. The second type states, $[\Sigma^{*} \Delta]_{(0,5/2)}$,$[\Sigma^{*} \Delta]_{(3,1/2)}$, $[\Delta\Delta]_{(0,3)}$ and $[\Delta\Delta]_{(3,0)}$ are also bound states, but with broad widths. $[\Xi\Omega - \Xi^{*}\Omega]_{(1,1/2)}$, $[\Xi\Xi]_{(0,1)}$, and $[N \Omega]_{(2,1/2)}$ are third type states. They, like {\em d}, are weakly bound only if the chiral fields can provide attraction between baryons.Comment: Latex files, 1 figur

Deltaron Dibaryon Structure in Chiral SU(3) Quark Model

We discuss the structure of Deltaron dibaryon in the chiral SU(3) quark model. The energy of Deltaron is obtained by considering the coupling of the $\Delta\Delta$ and $CC$ (hidden color) channels. The effects of various parameters on the Deltaron mass are also studied. It is shown that the mass of Deltaron is lower than the mass of $\Delta\Delta$ but higher than the mass of $\Delta N \pi$.Comment: 15 pages, Late

Saskatchewan corn cultivars for grazing and silage: relationship between crop heat units and nutritional value

Non-Peer Reviewe

Analysis and design of power management scheme for an on-board solar energy storage system

This paper investigates the power management issues in a mobile solar energy storage system. A multi-converter based energy storage system is proposed, in which solar power is the primary source while the grid or the diesel generator is selected as the secondary source. The existence of the secondary source facilitates the battery state of charge detection by providing a constant battery charging current. Converter modeling, multi-converter control system design, digital implementation and experimental verification are introduced and discussed in details. The prototype experiment indicates that the converter system can provide a constant charging current during solar converter maximum power tracking operation, especially during large solar power output variation, which proves the feasibility of the proposed design

N-N Interactions in the Extended Chiral SU(3) Quark Model

The chiral SU(3) quark model is extended to include coupling between vector chiral field and quarks. By using this model, the phase shifts of NN scattering for different partial waves are studied. The results are very similar to those of the chiral SU(3) quark model calculation, in which one gluon exchange (OGE) plays dominate role in the short range part of the quark-quark interactions. Only in the $^1S_0$ case, the one channel phase shifts of the extended chiral SU(3) quark model are obviously improved.Comment: 15 pages, 6 figure

A study of pentaquark Θ\Theta state in the chiral SU(3) quark model

The structure of the pentaquark state uudd-sbar is studied in the chiral SU(3) quark model as well as in the extended chiral SU(3) quark model, in which the vector meson exchanges are included. Four configurations of JP=1/2- and four of JP=1/2+ are considered. The results show that the isospin T=0 state is always the lowest one for both JP=1/2- and JP=1/2+ cases in various models. But the theoretical value of the lowest one is still about 200-300 MeV higher than the experimental mass of $\Theta$. It seems that a dynamical calculation should be done for the further study.Comment: 9 page

Possible Dibaryons with Strangeness s=-5

In the framework of $RGM$, the binding energy of the six quark system with strangeness s=-5 is systematically investigated under the SU(3) chiral constituent quark model. The single $\Xi^*\Omega$ channel calculation with spins S=0 and 3 and the coupled $\Xi\Omega$ and $\Xi^*\Omega$ channel calculation with spins S=1 and 2 are considered, respectively. The results show following observations: In the spin=0 case, $\Xi^* \Omega$ is a bound dibaryon with the binding energy being $80.0 \sim 92.4 MeV$. In the S=1 case, $\Xi\Omega$ is also a bound dibaryon. Its binding energy is ranged from $26.2 MeV$ to $32.9 MeV$. In the S=2 and S=3 cases, no evidence of bound dibaryons are found. The phase shifts and scattering lengths in the S=0 and S=1 cases are also given.Comment: 10 pages, late

Entangled light in transition through the generation threshold

We investigate continuous variable entangling resources on the base of two-mode squeezing for all operational regimes of a nondegenerate optical parametric oscillator with allowance for quantum noise of arbitrary level. The results for the quadrature variances of a pair of generated modes are obtained by using the exact steady-state solution of Fokker-Planck equation for the complex P-quasiprobability distribution function. We find a simple expression for the squeezed variances in the near-threshold range and conclude that the maximal two-mode squeezing reaches 50% relative to the level of vacuum fluctuations and is achieved at the pump field intensity close to the generation threshold. The distinction between the degree of two-mode squeezing for monostable and bistable operational regimes is cleared up.Comment: 7 pages, 4 figures; Content changed: more details added to the discussion. To be published in Phys. Rev.