相关论文: 3D eclipse mapping in AM Herculis systems - `Genet…
We present a magnetic stripping model for AM Her type objects. Our model is based on an equilibrium condition between ram pressure and magnetic pressure in a stiff dipolar magnetic field. We investigate the detailed geometry of the…
Aims: We aim to derive the absolute parameters of the components of AD And, AL Cam, and V338 Her, interpret their orbital period changes and discuss their evolutionary status. Methods: New and complete multi-filter light curves of the…
The advent of high-resolution spectroscopy as a method for exoplanet atmospheric characterization has expanded our capability to study non-transiting planets, increasing the number of planets accessible for observation. Many of the most…
We review the main observational characteristics of AM Herculis stars (polars) at X-ray, EUV, UV, IR and optical wavelengths. Particular emphasis is given to multi-epoch, multi-wavelength observations of the eclipsing polar HU Aqr (RX…
Mapping exoplanets across phases and during secondary eclipse is a powerful technique for characterizing Hot Jupiters in emission. Since these planets are expected to rotate about axes normal to their orbital planes, with rotation periods…
The formation and properties of accretion discs and circumstellar material in Algol-type systems is not very well understood. In order to study the underlying physics of these structures, we have calculated synthetic Halpha spectra of TT…
We present phase-resolved spectroscopy of AM Herculis obtained with the HST/GHRS when the system was in a high state. The ultraviolet light curve shows a quasi-sinusoidal modulation, which can be explained by a hot spot on the rotating…
We present phase-resolved spectroscopy of the bright, eclipsing polar HU Aqr obtained with high time (~30sec) and spectral (1.6 A) resolution when the system was in a high accretion state. The trailed spectrograms reveal clearly the…
Observations and models of transiting hot Jupiter exoplanets indicate that atmospheric circulation features may cause large spatial flux contrasts across their daysides. Previous studies have mapped these spatial flux variations through…
We present RXTE observations of the eclipsing X-ray binary Hercules X-1 conducted during an anomalous low state. Data reduction reveals a light curve over 2.7 orbital cycles remarkably similar to optical and UV light curves which are…
DQ Herculis was the Summer 1997 WET northern-hemisphere primary target. The O-C phase diagram of the 71-s signal reveals out-of-eclipse phase variations resulting from the self eclipses of a nearly edge-on, non-axisymmetric disc. We work…
We utilize multi-dimensional simulations of varying equatorial jet strength to predict wavelength dependent variations in the eclipse times of gas-giant planets. A displaced hot-spot introduces an asymmetry in the secondary eclipse light…
We conducted radio-interferometric observations of the well known binary cataclysmic system AM Herculis. This particular system is formed by the magnetic white dwarf (primary) and the red dwarf (secondary), and is the prototype of so-called…
High precision lightcurves combined with eclipse mapping techniques can reveal the horizontal and vertical structure of a planet's thermal emission and the dynamics of hot Jupiters. Someday, they even may reveal the surface maps of rocky…
In spite of a large number of global three-dimensional (3D) magneto-hydrodynamical (MHD) simulations of accretion flows and jets being made recently, their astrophysical relevance for realistic situations is not well known. In order to…
We report photopolarimetric observations of a new eclipsing polar (AM Herculis system) discovered in the Calan-Tololo survey. The photometry and polarimetry are modulated on a period of ~101 minutes. Circular polarization variations are…
DQ Herculis (Nova Herculis 1934) is a deeply eclipsing cataclysmic variable containing a magnetic white dwarf primary. The accretion disk is thought to block our line of sight to the white dwarf at all orbital phases due to its extreme…
Recent Spitzer infrared measurements of hot Jupiter eclipses suggest that eclipse mapping techniques could be used to spatially resolve the day-side photospheric emission of these planets using partial occultations. As a first step in this…
The observation of eclipses during X-rays flares taking place in active cool stars binaries allows us to calculate the position and size of the flares. This information cannot be derived by analyzing the decay of the flares, a frequently…
The stabilization mechanisms of fully premixed NH3/H2/air flames anchored behind a bluff body are investigated using combined experiments and direct numerical simulations. Particular attention is given to the interplay between preferential…