10,332 research outputs found

    First R and I Lights and Their Photometric Analyses of GSC 02393-00680

    Full text link
    We obtained complete RR and II light curves of GSC 02393-00680 in 2008 and analyzed them with the 2003 version of the W-D code. It is shown that GSC 02393-00680 is a W-type shallow contact binary system with a high mass ratio q=1.600q=1.600 and a degree of contact factor f=5.0f=5.0%(\pm1.3%). It will be a good example to check up on the TRO theory. A period investigation based on all available data suggests that the system has a small-amplitude period oscillation (A3=0.d0030A_3=0.^{d}0030; T3=1.92T_3=1.92years). This may indicate it has a moderate mass close third body, which is similar to XY Leo

    Dynamics and correlation length scales of a glass-forming liquid in quiescent and sheared conditions

    Full text link
    We numerically study dynamics and correlation length scales of a colloidal liquid in both quiescent and sheared conditions to further understand the origin of slow dynamics and dynamic heterogeneity in glass-forming systems. The simulation is performed in a weakly frustrated two-dimensional liquid, where locally preferred order is allowed to develop with increasing density. The four-point density correlations and bond-orientation correlations, which have been frequently used to capture dynamic and static length scales ξ\xi in a quiescent condition, can be readily extended to a system under steady shear in this case. In the absence of shear, we confirmed the previous findings that the dynamic slowing down accompanies the development of dynamic heterogeneity. The dynamic and static length scales increase with α\alpha-relaxation time τα\tau_{\alpha} as power-law ξ∼ταμ\xi\sim\tau_{\alpha}^{\mu} with μ>0\mu>0. In the presence of shear, both viscosity and τα\tau_{\alpha} have power-law dependence on shear rate in the marked shear thinning regime. However, dependence of correlation lengths cannot be described by power laws in the same regime. Furthermore, the relation ξ∼ταμ\xi\sim\tau_{\alpha}^{\mu} between length scales and dynamics holds for not too strong shear where thermal fluctuations and external forces are both important in determining the properties of dense liquids. Thus, our results demonstrate a link between slow dynamics and structure in glass-forming liquids even under nonequilibrium conditions.Comment: 9 pages, 17 figures. Accepted by J. Phys.: Condens. Matte
    • …
    corecore