Three-body effective interactions emerging between parallel cylindrical rods immersed in a nematic liquid crystals are calculated within the Landau-de Gennes free-energy description. Collinear, equilateral and midplane configurations of the three colloidal particles are considered. In the last two cases the effective triplet interaction is of the same magnitude and range as the pair one.

The results of single-dish observations of lowand high-J transitions of selected molecules from protoplanetary disks around two T Tauri stars (LkCa 15 and TW Hya) and two Herbig Ae stars (HD 163296 and MWC 480) are reported. Simple molecules such as CO, CO, HCO, CN and HCN are detected. Several lines of H2CO are found toward the T Tauri star LkCa 15 but not in other objects. No CH3OH has been d...

Context. Broad emission lines are emitted in the surroundings of supermassive black holes in the centers of active galactic nuclei (AGN). This region is spatially not resolved. Aims. We intend to get information on the structure and geometry of this broad emitting line region based on line profile observations. Methods. We model the rotational and turbulent velocities in the line-emitting regio...

Criteria for gravitational collapse of expanding shells in rotating, shearing galaxy disks were determined using three-dimensional numerical simulations in the thin shell approximation. The simulations were run over a grid of 7 independent variables, and the resultant probabilities for triggering and unstable masses were determined as functions of 8 dimensionless parameters. When the ratio of t...

We construct a sample of nearly 30,000 main-sequence stars with 4500 K < Teff 5000 and stellar ages estimated by the chromospheric activity−age relation. This is used to determine age distribution in R–Z plane Galaxy, where R projected Galactocentric distance disk midplane Z height above midplane. As ∣Z∣ increases, percentage old becomes larger. It known that scale-height Galactic increases as ...

In this paper, we study the effect of MHD turbulence on the dynamics of dust particles in protoplanetary disks. We vary the size of the particles and relate the dust evolution to the turbulent velocity fluctuations. We performed numerical simulations using two Eulerian MHD codes, both based on finite difference techniques: ZEUS– 3D and NIRVANA. These were local shearing box simulations incorpor...

We present ~120,000 Spitzer/IRAC candidate young stellar objects (YSOs) based on surveys of the Galactic midplane between l~255 deg and 110 deg, including GLIMPSE I, II, 3D, Vela-Carina, Cygnus X, SMOG (613 square degrees), augmented by near-infrared catalogs. employed a classification scheme that uses flexibility tailored statistical learning method curated YSO datasets to take full advantage ...

Abstract As the earliest stage of planet formation, massive, optically thick, and gas-rich protoplanetary disks provide key insights into physics star formation. When viewed edge-on, high-resolution images offer a unique opportunity to study both radial vertical structures these relate this settling, drift, grain growth, changes in midplane temperatures. In work, we present multi-epoch Hubble S...