We present kinematic measurements of the thick and thin disks in two edge-on galaxies. We have derived stellar rotation curves at and above the galaxies’ midplanes using Ca ii triplet features measured with the GMOS spectrograph on Gemini North. In one galaxy, FGC 1415, the kinematics above the plane show clear rotation that lags that of the midplane by ∼20-50%, similar to the behavior seen in ...

Following stepping in-place on the surface of a rotating circular treadmill, a subject attempting to step in-place or walk in a straight line across the floor without vision will rotate relative to space. This adaptation, termed podokinetic after-rotation (PKAR), transfers to backward walking following forward walking on the rotating disk. We asked whether adaptation obtained during stepping in...

in order to simulate the rotating disk contactor all hydrodynamic parameters, dispersed phase hold-up, characteristic velocity, mean drop size, drop size distribution, axial mixing and mass transfer have been taken into account. mechanisms of mass transfer (stagnant, circulating, oscillating drops) were used in this study. column height found from effect of mean drop size and drop size distribu...

The latest studies of massive star evolution indicate that an initially rapidly rotating star with sufficiently low metallicity can produce a rapidly rotating, massive stellar core that could be a progenitor of long-soft gamma-ray bursts (LGRBs). Motivated by these studies, we follow the collapse of a rapidly rotating massive stellar core to a ’collapsar’ black hole (BH) surrounded by a massive...

The discrete kinetic model is used to study the propagation of sound waves in system of hard-disk-like rotating stars (or vortex gases). The anomalous (negative) attenuation or amplification which is possibly due to the binary collision of a dilute-enough rotating disk (or vortex-gas) system (each with opposite-sign rotating direction or angular momenta but the total (net) angular momenta or vo...

In this paper Optimal Homotopy Asymptotic Method (OHAM) has been used to the flow past a rotating disk. This method is applied to the problem obtained from flow past a rotating disk shows its efficiency and effectiveness. This method control the convergence of approximate solution in a convenient way, when it is compared with other methods of solution found in the literature as Homotopy Perturb...

We examine the relationship between the frequency of close companions (stellar and planetary companions with orbital periods<5 yr) and the metallicity of their Sun-like ( FGK) hosts. We confirm and quantify a 4 positive correlation between host metallicity and planetary companions. We find little or no dependence on spectral type or distance in this correlation. In contrast to the metallicity d...

We have performed several simulations of black hole systems (non-rotating, black hole spin parameter a = 0.0 and rapidly rotating, a = 0.95) with a geometrically thin Keplerian disk using the newly developed RAISHIN code. The simulation results show the formation of jets driven by the Lorentz force and the gas pressure gradient. The jets have mildly relativistic speed (& 0.4 c). The matter is c...

The instability modes of the infinitesimally thin self-gravitating disk, which is composed of rotating and non-rotating parts, are investigated. By solving the dispersion relation numerically under various physical situations, two growing modes are found. They are the modified Jeans mode of rotating component or non-rotating one and the Landau mode by wave-particle (non-rotating component) inte...

Recent numerical simulations and analytical models of magnetically collimated plasma outflows from a uniformly rotating central gravitating object and/or a Keplerian accretion disk have shown that relatively low mass and magnetic fluxes reside in the produced jet. Observations however indicate that in some cases, as in jets of YSO’s, the collimated outflow carries higher fluxes than these simul...