We present the results of exploratory HST observations to detect the emission lines of ions in the β Pictoris disk with the spectrograph slit placed off the star. Possible emission lines from Fe ii have been detected at ∼ 10 −14 erg cm −2 s −1 at 0.5 ′′ from β Pictoris, which would suggest a total Fe ii density of > ∼ 2 · 10 −2 cm −3 at 10 AU. This detection needs confirmation. If real, it requ...

The purpose of the study is to substantiate parameters a spherical disk working body. New technology tillage slope fields that prevent water erosion, design scheme ripper for its implementation presented. consists lower and upper bodies “paraglider” type disk. applied laws rules theoretical mechanics, agricultural mathematical statistics, methods strain measurement given in existing regulatory ...

We present the results of axisymmetric time-dependent hydrodynamic calculations of line-driven winds from accretion disks in active galactic nuclei (AGN). We assume the disk is flat, Keplerian, geometrically thin, and optically thick, radiating according to the α-disk prescription. The central engine of the AGN is a source of both ionizing X-rays and wind-driving ultraviolet (UV) photons. To ca...

Traditional technologies and machines for sowing cereals lead to increased water erosion on sloping fields the washout of crops, respectively, causing a sharp decline in yields. The authors proposed anti-erosion technology machinery fields. research aims justify parameters ridge forming machine basic principles methods classical mechanics, mathematical analysis, statistics were used this study....

As many as 5 ice giants—Neptune-mass planets composed of ∼90% ice and rock and ∼10% hydrogen—are thought to form at heliocentric distances of ∼10–25 AU on closely packed orbits spaced ∼5 Hill radii apart. Such oligarchies are ultimately unstable. Once the parent disk of planetesimals is sufficiently depleted, oligarchs perturb one another onto crossing orbits. We explore both the onset and the ...

The effectiveness of manure incorporation in reducing the numbers of adult lesser mealworms emerging from caged-layer poultry manure applied to agricultural fields was examined in summer 2002 and 2004. Incorporation treatments included control (no incorporation), disk (7-cm depth), harrow (15-cm depth), chisel plow (30-cm depth), and moldboard plow (33-cm depth) on silt loam soils in New York s...