相关论文: White dwarfs in a uniform sphere approximation, wi…
We show that recently proposed white dwarf models with masses well in excess of the Chandrasekhar limit, based on modifying the equation of state by a super-strong magnetic field in the centre, are very far from equilibrium because of the…
In a brief article published in 1931 and expanded in 1935, the Indian astrophysicist Subrahmanyan Chandrasekhar shared an important astronomical discovery where he introduced what is now known as Chandrasekhar limit. This limit establishes…
It is agreed that Chandrasekhar mass and central density of white dwarfs are independent, which means that there is a whole series of stars having radius and central density as parameters that all have the same Chandrasekhar mass. In this…
We present new determinations of effective temperature, surface gravity, and masses for a sample of 46 hot DA white dwarfs selected from the EUVE and ROSAT Wide Field Camera bright source lists in the course of a near-IR survey for low mass…
We report on an undergraduate student project initiated in the summer semester of 2004 with the aim to establish equations of state for white dwarfs and neutron stars for computing mass-radius relations as well as corresponding maximum…
The DA white dwarfs in the Sloan Digital Sky Survey, as analyzed in the papers for Data Releases 1 and 4, show an increase in surface gravity towards lower effective temperatures below 11500 K. We study the various possible explanations of…
We present new numerical method to compute structures of differentially rotating white dwarfs with thermal stratification. Our models have cores composed of ions and completely degenerate electrons and have isentropic envelopes composed of…
White dwarfs are compact objects that stand against gravitational collapse by their internal pressure of degenerate matter. In this work we aimed to perform an introductory study on these stars, using two equations of state (EOS): (I) an…
We compare the mass distribution of central stars of planetary nebulae (CSPN) with those of their progeny, white dwarfs (WD). We use a dynamical method to measure masses with an uncertainty of 0.02 M$_\odot$. The CSPN mass distribution is…
We compute static equilibria of white dwarf stars containing strong poloidal magnetic field, and present the modification of white dwarf mass-radius relation caused by the magnetic field. We find that a maximum white dwarf mass of about…
We have investigated the relationship between the kinematics and mass of young (<3x10^8 years) white dwarfs using proper motions. Our sample is taken from the colour selected catalogues of SDSS (Eisenstein et al. 2006) and the Palomar-Green…
Recent studies of the atmospheres of carbon-rich (DQ) white dwarfs have demonstrated the existence of two different populations that are distinguished by the temperature range, but more importantly, by the extremely high masses of the…
First results are presented for a Hubble Space Telescope Advanced Camera for Surveys snapshot study of white dwarfs with likely red dwarf companions. Of 48 targets observed and analyzed so far, 27 are totally or partially resolved into two…
White Dwarf luminosities are powerful age indicators, whose calibration should be based on reliable models. We discuss the uncertainty of some chemical and physical parameters and their influence on the age estimated by means of white dwarf…
We address the issue of stability of recently proposed significantly super-Chandrasekhar white dwarfs. We present stable solutions of magnetostatic equilibrium models for super-Chandrasekhar white dwarfs pertaining to various magnetic field…
In quantum gravity phenomenology, the effect of the generalized uncertainty principle (GUP) on white dwarfs has been given much attention in the literature. However, these studies assume a zero temperature equation of state (EoS),…
The mass-radius relationship of white dwarfs (WDs) is one of their defining characteristics, largely derived from electron degeneracy pressure. We present a model-independent study of the observed mass-radius relationship in WD binaries of…
We present a study of the dependence of the mass-radius relation for DA white dwarf stars on the hydrogen envelope mass and the impact on the value of log g, and thus the determination of the stellar mass. We employ a set of full…
The properties of uniformly rotating white dwarfs (RWDs) are analyzed within the framework of general relativity. Hartle's formalism is applied to construct the internal and external solutions to the Einstein equations. The WD matter is…
The white dwarf mass distribution has been studied primarily at two extremes: objects that presumably evolved as single stars and members of close binaries that likely underwent substantial interaction. This work considers the intermediate…