相关论文: Neutron Star Planets: Atmospheric processes and ha…
Volatile loss from exoplanetary atmospheres and its possible implications for the longevity of habitable surface conditions is a topic of vigorous debate currently. The vast majority of the habitable zone terrestrial-like exoplanets known…
Estimates of the magnetic field of neutron stars in X-ray pulsars are obtained using the hypothesis of the equilibrium period for disk and wind accretion and also from the BATSE data on timing of X-ray pulsars using the observed maximum…
We consider the habitability of Earth-analogs around stars of different masses, which is regulated by the stellar lifetime, stellar wind-induced atmospheric erosion, and biologically active ultraviolet (UV) irradiance. By estimating the…
We present a detailed investigation of atmospheres around accreting neutron stars with high magnetic field ($B\gtrsim 10^{12}$ G) and low luminosity ($L\lesssim 10^{33}$ erg/s). We compute the atmospheric structure, intensity and emergent…
For centuries, humanity wondered if there were other worlds like ours in the Universe. For about a quarter of a century, we have known that planetary systems exist around other stars, and more than 3800 exoplanetary systems have been…
Among the many different classes of stellar objects, neutron stars provide a unique environment where we can test (at the same time) our understanding of matter with extreme density, temperature, and magnetic field. In particular, the…
Rotation-powered "recycled" millisecond pulsars are a variety of rapidly-spinning neutron stars that typically show thermal X-ray radiation due to the heated surface of their magnetic polar caps. Detailed numerical modeling of the…
Model spectra of neutron star atmospheres are nowadays widely used to fit the observed thermal X-ray spectra of neutron stars. This fitting is the key element in the method of the neutronstar radius determination. Here, we present the basic…
Neutron stars -- compact objects with masses similar to that of our Sun but radii comparable to the size of a city -- contain the densest form of matter in the universe that can be probed in terrestrial laboratories as well as in earth- and…
We investigate how rapid stellar rotation commonly seen in A/F stars can influence planet habitability. Specifically, we model how rapid rotation influences a planet's irradiation and determine the location of the habitable zone for stars…
We analyze the effect of companion stars on the bulk density of 29 planets orbiting 15 stars in the Kepler field. These stars have at least one stellar companion within 2", and the planets have measured masses and radii, allowing an…
Within the next few years, several instruments aiming at imaging extrasolar planets will see first light. In parallel, low mass planets are being searched around red dwarfs which offer more favorable conditions, both for radial velocity…
Measuring the spin of Accreting Neutron Stars is important because it can provide constraints on the Equation of State of ultra-dense matter. Particularly crucial to our physical understanding is the discovery of sub-millisecond pulsars,…
The process of mass-exchange between the components of High Mass X-ray Binary (HMXB) systems with neutron stars undergoing wind-fed accretion is discussed. The X-ray luminosity of these systems allows us to evaluate the mass capture rate by…
The discovery of the first extra-solar planet surrounding a main-sequence star was announced in 1995, based on very precise radial velocity (Doppler) measurements. A total of 34 such planets were known by the end of March 2000, and their…
We report on the discovery and validation of a transiting long-period mini-Neptune orbiting a bright (V = 9.0 mag) G dwarf (TOI 4633; R = 1.05 RSun, M = 1.10 MSun). The planet was identified in data from the Transiting Exoplanet Survey…
X-rays and extreme ultraviolet radiation impacting on a gas produce a variety of effects that, depending on the electron content, may provide a significant heating of the illuminated region. In a planetary atmosphere of solar composition,…
The investigation of exoplanetary habitability is integral to advancing our knowledge of extraterrestrial life potential and detailing the environmental conditions of distant worlds. In this analysis, we explore the properties of exoplanets…
We study the dynamical stability of an additional, potentially habitable planet in the HD 47186 planetary system. Two planets are currently known in this system: a "hot Neptune" with a period of 4.08 days and a Saturn-mass planet with a…
We analyze several aspects of the recently noted neutron star collapse instability in close binary systems. We utilize (3+1) dimensional and spherical numerical general relativistic hydrodynamics to study the origin, evolution, and…