Related papers: Rotating Disks and Non-Kinematic Double Peaks
In the Galactic microquasars with double peak kHz quasi-periodic oscillations (QPOs), the ratio of the two frequencies is 3:2. This supports the suggestion that double peak kHz QPOs are due to a non-linear resonance between two modes of…
We consider the consequences of appreciable line optical depth for the profile shape of X-ray emission lines formed in stellar winds. The hot gas is thought to arise in distributed wind shocks, and the line formation is predominantly via…
In this Letter we further explore the idea, suggested previously by Klu{\'z}niak and collaborators, that the high frequency QPOs may be explained as a resonant coupling between the neutron star spin and two epicyclic modes of accretion disk…
We present an improved method to measure the rotation curves for disks with non-axisymmetric brightness profiles initially published in Teague et al. (2018a). Application of this method to the well studied AS$~$209 system shows substantial…
One of the most intriguing spectral features of WR binary stars is the presence of time-dependent line profiles. Long term observations of several systems revealed the periodicity of this variability, synchronized with the orbital movement.…
The outer disks of galaxies present a unique laboratory for studying the process of disk formation. A considerable fraction of observed disks exhibit a break in their surface brightness profiles. The ubiquity of these features points to a…
We report the observation of a novel nonlinear effect in the hard x-ray range. Upon illuminating Fe and Cu metal foils with intense x-ray pulses tuned near their respective K edges, photons at nearly twice the incoming photon energy are…
The vertical structure of stationary thin accretion discs is calculated from the energy balance equation with heat generation due to microscopic ion viscosity {\eta} and electron heat conductivity {\kappa}, both depending on temperature. In…
High frequency (millisecond) quasi-periodic oscillations (HF QPOs) are observed in the X-ray power-density spectra of several microquasars and low mass X-ray binaries. Two distinct QPO peaks, so-called twin peak QPOs, are often detected…
We study strong gravitational lensing by spiral galaxies, modeling them as infinitely thin uniform disks embedded in singular isothermal spheres. We derive general properties of the critical curves and caustics analytically. The…
A new method is developed which permits the reconstruction of the surface-density distribution in the galactic disk of finite radius from an arbitrary smooth distribution of the angular velocity via two simple quadratures. The existence of…
We give a detailed description about the reflected spectrum of a few-cycle pulse propagating through a resonant dense medium. An unexpected low-frequency spike appeared in the red edge of the spectrum. To figure out the origin of this…
A nonperturbative, purely numerical, solution of the reduced Rayleigh equation for the scattering of p- and s-polarized light from a dielectric film with a two-dimensional randomly rough surface deposited on a planar metallic substrate, has…
Protoplanets and circumplanetary disks are rather elusive in their thermal IR emission. Yet they are cornerstone to the most popular interpretations for the protoplanetary disks structures observed in the gas and dust density fields, even…
Asymmetries in the distribution of light and neutral hydrogen are often observed in spiral galaxies. Here, attention is drawn to the presence of large-scale asymmetries in their kinematics. Two examples of kinematically lopsided galaxies…
We analyze the distribution of G and K type stars towards the Galactic poles using RAVE and ELODIE radial velocities, 2MASS photometric star counts, and UCAC2 proper motions. The combination of photometric and 3D kinematic data allows us to…
Transition disks are protoplanetary disks with inner cavities possibly cleared by massive companions, which makes them prime targets to observe at high resolution to map their velocity structure. We present ALMA Band 6 dust and gas…
We have developed a method to compute the possible distribution of radio emission regions in a typical pulsar magnetosphere, taking into account the viewing geometry and rotational effects of the neutron star. Our method can estimate the…
Calculations are performed for the spectral line profiles and images of astrophysical maser radiation that emerges from isolated spheres and thin disks viewed edge-on. In contrast to previous investigations where various approximations are…
[Abridged] Optically thick, geometrically thin accretion disks around supermassive black holes are thought to contribute to broad-line emission in type-1 active galactic nuclei (AGN). However, observed emission line profiles most often…