Search

We propose a reliable scheme to recover the conventional photon blockade effect in the dispersive Jaynes-Cummings model, which describes a two-level atom coupled to a single-mode cavity field in the large-detuning regime. This is achieved by introducing a transversal driving to the atom and then photonic nonlinearity is obtained. The eigenenergy spectrum of the system is derived analytically and the photon blockade effect is confirmed by numerically calculating the photon-number distributions and equal-time second-order correlation function of the cavity field in the presence of system dissipations. We find that the conventional photon blockade effect can be recovered at proper atomic and cavity-field drivings. This work will provide a method to generate the conventional photon blockade effect in the dispersively coupled quantum optical systems., Comment: 9 pages, 6 figures

High precision CCD observations of six totally eclipsing contact binaries were presented and analyzed. It is found that only one target is an A-type contact binary (V429 Cam), while the others are W-type contact ones. By analyzing the times of light minima, we discovered that two of them exhibit secular period increase while three manifest long-term period decrease. For V1033 Her, a cyclic variation superimposed on the long-term increase was discovered. By comparing the Gaia distances with those calculated by the absolute parameters of 173 contact binaries, we found that Gaia distance can be applied to estimate absolute parameters for most contact binaries. The absolute parameters of our six targets were estimated by using their Gaia distances. The evolutionary status of contact binaries was studied, we found that the A- and W- subtype contact binaries may have different formation channels. The relationship between the spectroscopic and photometric mass ratios for 101 contact binaries was presented. It is discovered that the photometric mass ratios are in good agreement with the spectroscopic ones for almost all the totally eclipsing systems, which is corresponding to the results derived by Pribulla et al. and Terrell & Wilson., Comment: 38 pages, 8 figures, and 10 tables, accepted by AJ

Based on the relativistic transport model ART with the hadronic equation of state extended to have a phase transition via the use of the MIT bag model, properties of phase transition of dense nuclear matter formed in relativistic heavy-ion collisions are investigated. Proton sideward and directed flows are calculated with different equation of states in Au + Au collisions at beam energies of 2, 4, 6 and 8 GeV/nucleon. Compared with AGS experimental data in existence, the boundary of first-order phase transition is roughly confined, i.e., in the range of 2.5-4 times saturation density with temperature about 64-94 MeV. Such constraints are useful for ongoing RHIC Beam Energy Scan-II program to study the QCD matter phase diagram., Comment: 5 pages, 5 figures

The nuclear symmetry energy, which describes the energy difference of per proton and neutron in nuclear matter, has been extensively studied within the last two decades. Around saturation density, both the value and the slope of the nuclear symmetry energy have been roughly constrained, its high-density behavior is now still in argument. Probing high-density symmetry energy at terrestrial laboratories is being carried out at facilities that offer radioactive beams worldwide. While relevant experiments are being conducted, we theoretically developed more advanced isospin-dependent transport model including new physics such as nucleon-nucleon short-range correlations and in-medium isospin-dependence of baryon-baryon scattering cross section. New sensitive probes of high-density symmetry energy are provided, such as squeezed-out neutron to proton ratio, photon and light cluster as well as the production of mesons with strangeness or hidden strangeness. The blind spots of probing the high-density symmetry energy by sensitive observable are demonstrated. Model dependence of frequently used sensitive probes of the symmetry energy has been studied thoroughly based on different transport models. A qualitative observable of neutron to proton ratio at high emitting energy is proposed to probe the high-density symmetry energy qualitatively. The probed density regions of the symmetry energy are carefully studied. Effects of nucleon-nucleon short-range correlations on the some sensitive observables of the symmetry energy in heavy-ion collisions are explored carefully. Probing the curvature of the symmetry energy by involving the slope information of the symmetry energy at saturation point in the transport model is proposed., Comment: 13 pages, 25 figures

Based on the Isospin-dependent Boltzmann-Uehling-Uhlenbeck (IBUU) transport model, the in-medium nucleon-nucleon inelastic scattering ( which is dominated by pion production at low and intermediate energies) is explored. It is found that the in-medium modification of nucleon-nucleon inelastic scatterings appears to reduce the neutron to proton ratio n/p at higher kinetic energies. Although the in-medium modification of nucleon-nucleon inelastic scatterings, as expected, affects the value of $\pi^-/\pi^+$ ratio, considering a series of undetermined properties of delta resonance and $\pi$ in medium, the energetic neutron to proton ratio n/p is more suitable to be used to probe the in-medium correction of nucleon-nucleon inelastic scatterings., Comment: 6 pages, 4 figures, PRC in production

The first charge-coupled device photometric light curves in B, V, R${_c}$, and I${_c}$ bands of the short-period contact binary star OQ Cam are presented. Through analyzing the light curves with the Wilson-Devinney code, it is found that OQ Cam is a W-type shallow contact binary star with a contact degree of f =20.2%. Based on the O-C analyzing, the orbit period displays a long term increasing with a rate of $dP/dt=4.40\times10{^{-7}} day \cdot year{^{-1}}$. The increasing in orbit period can be interpreted by mass transfer from the less massive component to the more massive one. As the orbit period increasing, OQ Cam would evolve from the present shallow contact configuration to a none contact stage. So it may be a potential candidate to confirm the thermal relaxation oscillation theory., Comment: 11 pages, 6 figures, and 5 tables, accepted by RAA

Based on the Isospin-dependent Boltzmann-Uehling-Uhlenbeck (IBUU) transport model, the isotope Sn+Sn reactions at 270 MeV/nucleon are investigated. It is shown that nucleon and meson observables in the Sn+Sn reactions at 270 MeV/nucleon cannot effectively probe the high-density symmetry energy. These observables, however, are sensitive to the curvature of the symmetry energy. It thus sheds light on the study of the high-density behavior of the nuclear symmetry energy by extracting the curvature of the symmetry energy through the interpretation of forthcoming RIBF/RIKEN related data., Comment: 5 pages, 8 figures