In this paper, we present the properties of 10 halo globular clusters with luminosities $Lsimeq 5-7times 10^5{L_odot}$ in the Local Group galaxy M33 using the images of {it Hubble Space Telescope} Wide Field Planetary Camera 2 in the F555W and F814W
bands. We obtained ellipticities, position angles and surface brightness profiles for them. In general, the ellipticities of M33 sample clusters are similar to those of M31 clusters. The structural and dynamical parameters are derived by fitting the profiles to three different models combined with mass-to-light ratios ($M/L$ values) from population-synthesis models. The structural parameters include core radii, concentration, half-light radii {bf and} central surface brightness. The dynamical parameters include the integrated cluster mass, integrated binding energy, central surface mass density {bf and} predicted line-of-sight velocity dispersion at the cluster center. The velocity dispersions of four clusters predicted here agree well with the observed dispersions by Larsen et al. The results here showed that the majority of the sample halo globular clusters are well fitted by King model as well as by Wilson model, and better than by Sersic model. In general, the properties of clusters in M33, M31 and the Milky Way fall in the same regions of parameter spaces. The tight correlations of cluster properties indicate a fundamental plane for clusters, which reflects some universal physical conditions and processes operating at the epoch of cluster formation.
We present experimental evidence supporting the postulation that the secondary effects of light-assisted collisions are the main reason that the superradiant light scattering efficiency in condensates is asymmetric with respect to the sign of the pum
p-laser detuning. Contrary to the recent experimental study, however, we observe severe and comparable heating with all three pump-laser polarizations. We also perform two-color, double-pulse measurements to directly study the degradation of condensate coherence and the resulting impact on the superradiant scattering efficiency.
A deformed relativistic Hartree-Bogoliubov (DRHB) model is developed aiming at a proper description of exotic nuclei, particularly deformed ones with large spatial extension. In order to give an adequate description of both the contribution of the co
ntinuum and the large spatial distribution in exotic nuclei, the DRHB equations are solved in a Woods-Saxon basis in which the radial wave functions have proper asymptotic behaviors at large distance from the nuclear center which is crucial for the formation of halo. The formalism and the numerical procedure of the DRHB model in a Woods-Saxon basis are briefly presented.
Virtual Observatory (VO) is a data intensive online astronomical research and education environment, taking advantages of advanced information technologies to achieve seamless and uniform access to astronomical information. The concept of VO was intr
oduced in late of 1990s to meet challenges brought up with data avalanche in astronomy. This paper reviews current status of International Virtual Observatory Alliance, technical highlights from world wide VO projects, and a brief introduction of Chinese Virtual Observatory.
