相关论文: Ellipsars: Ring-like explosions from flattened sta…
Under the merger hypothesis, elliptical galaxies are built through mergers of gas-rich spirals. However, the relative paucity of HI in most normal ellipticals demands significant processing of atomic gas into other forms if this process is…
Flattened axisymmetric galactic potentials are known to host minor orbit families surrounding orbits with commensurable frequencies. The behavior of orbits that belong to these orbit families is fundamentally different than that of typical…
When a granular material is impacted by a sphere, its surface deforms like a liquid yet it preserves a circular crater like a solid. Although the mechanism of granular impact cratering by solid spheres is well explored, our knowledge on…
Stars grazing supermassive black holes on bound orbits may produce periodic flares over many passages, known as repeating partial tidal disruption events (TDEs). Here, we present 3D hydrodynamic simulations of sun-like stars over multiple…
We present collisionless simulations of dry mergers in groups of three to twenty-five galaxies to test the hypothesis that elliptical galaxies form at the centers of such groups. Mock observations of the central remnants confirm their…
We speculate that the universe is filled with stars composed of electromagnetic and dilaton fields which are the sources of the powerful gamma-ray bursts impinging upon us from all directions of the universe. We calculate soliton-like…
One of the central problems in supernova theory is the question how massive stars explode. Understanding the physical processes that drive the explosion is crucial for linking the stellar progenitors to the final remnants and for predicting…
Heartbeat stars are eccentric binary stars in short period orbits whose light curves are shaped by tidal distortion, reflection, and Doppler beaming. Some heartbeat stars exhibit tidally excited oscillations and present new opportunities…
Elliptical galaxies are modelled as homeoidally striated Jacobi ellipsoids where the peculiar velocity distribution is anisotropic, or equivalently as their adjoints configurations i.e. classical Jacobi ellipsoids of equal mass and axes, in…
We review the origin and structure of hot (cooling flow) gas in elliptical galaxies. X-ray observations can be used to determine the stellar mass to light ratio, the mass profiles of dark matter halos, and the interstellar magnetic field.…
Main-sequence stars earlier than spectral type ~F6 or so are expected to rotate rapidly due to their radiative exteriors. This rapid rotation leads to an oblate stellar figure. It also induces the photosphere to be hotter (by up to several…
Evolved stars dominate galactic spectra, enrich the galactic medium, expand to change their planetary systems, eject winds of a complex nature, produce spectacular nebulae and illuminate them, and transfer material between binary…
We provide a general analysis on the properties of emitting material of some rapidly evolving and luminous transients discovered recently with the Pan-STARRS1 Medium Deep Survey. It is found that these transients are probably produced by a…
We aim to understand how landslides affect the shape and rotational motion of small rubble planetary bodies. We limit ourselves to axisymmetric global landslides, and take the primordial shape of the body to also be axisymmetric. The…
An approximate strategy for studying the evolution of binary systems of extended objects is introduced. The stars are assumed to be polytropic ellipsoids. The surfaces of constant density maintain their ellipsoidal shape during the time…
Pulsar "standard model" of rotating magnetized conducting sphere surrounded by plasma is generalized in its essential parts for the case of oscillating star. Goldreich-Julian charge density, electromagnetic energy losses as well as polar…
We investigate the relativistic breakout of a shock wave from the surface of a star. In this process, each fluid shell is endowed with some kinetic and thermal energy by the shock, and then continues to accelerate adiabatically by…
Spectral molecular line profile observations of star-forming molecular clouds sometimes show distinct red asymmetric double-peaked molecular line profiles with weaker blue peaks and stronger red peaks. For some star-forming molecular…
In this paper we present new chemo-spectro-photometric models of elliptical galaxies in which infall of primordial gas is allowed to occur. They aim to simulate the collapse of a galaxy made of two components, i.e. luminous material and…
Emission of relativistic axions from transient sources, such as axion star explosions, can lead to observable signatures. We show that axion bursts from collapsing axion stars can be detectable over the wide range of axion masses $10^{-15}…