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Related papers: On The Evolution of Magnetic White Dwarfs

200 papers

Strong magnetic fields are observed in a substantial fraction of upper main sequence stars and white dwarfs. Many such stars are observed to exhibit photometric modulations as the magnetic poles rotate in and out of view, which could be a…

Solar and Stellar Astrophysics · Physics 2023-02-22 Jim Fuller , Stephane Mathis

White dwarfs and neutron stars are stellar objects with masses comparable to that of our sun. However, as the endpoint stages of stellar evolution, these objects do not sustain any thermonuclear burning and therefore can no longer support…

Astrophysics · Physics 2007-05-23 Shmuel Balberg , Stuart L. Shapiro

We investigate effects of the magnetic field on the propagation of laminar flames of nuclear reactions taking place in white dwarfs (WDs) with the mass close to the Chandrasekhar limit. We calculate the velocities of laminar flames parallel…

High Energy Astrophysical Phenomena · Physics 2015-06-04 Masamichi Kutsuna , Toshikazu Shigeyama

We construct radiative equilibrium models for strongly magnetized (B > 10^13 G) neutron-star atmospheres taking into account magnetic free-free absorption and scattering processes computed for two polarization modes. We include the effects…

Astrophysics · Physics 2009-11-06 Feryal Ozel

Millisecond pulsars with white dwarf companions have typical eccentricities $e\sim 10^{-6}-10^{-3}$. The eccentricities of helium white dwarfs are explained well by applying the fluctuation-dissipation theorem to convective eddies in their…

Solar and Stellar Astrophysics · Physics 2024-09-23 Yair Cohen , Sivan Ginzburg , Maya Levy , Tal Bar Shalom , Yoav Siman Tov

The transverse magnetoresistance of the Bechgaard salt (TMTSF)$_2$PF$_6$ has been measured for various pressures, with the field up to 24 T parallel to the lowest conductivity direction c$^{\ast}$. A quadratic behavior is observed in the…

Strongly Correlated Electrons · Physics 2009-11-07 N. Matsunaga , K. Yamashita , H. Kotani , K. Nomura , T. Sasaki , T. Hanajiri , J. Yamada , S. Nakatsuji , H. Anzai

M-dwarf stars provide very favourable conditions to find habitable worlds beyond our solar system. The estimation of the fundamental parameters of the transiting exoplanets rely on the accuracy of the theoretical predictions for radius and…

Solar and Stellar Astrophysics · Physics 2019-06-12 Santi Cassisi , Maurizio Salaris

Using images from the Hubble Space Telescope Advanced Camera for Surveys, we measure the rate of cooling of white dwarfs in the globular cluster 47 Tucanae and compare it to modelled cooling curves. We examine the effects of the outer…

Solar and Stellar Astrophysics · Physics 2017-10-26 Alysa Obertas , Ilaria Caiazzo , Jeremy Heyl , Harvey Richer , Jason Kalirai , Pier-Emmanuel Tremblay

The presence of ultra-high excitation (UHE) absorption lines (e.g., O VIII) in the optical spectra of several of the hottest white dwarfs poses a decades-long mystery and is something that has never been observed in any other astrophysical…

Solar and Stellar Astrophysics · Physics 2018-11-08 Nicole Reindl , M. Bainbridge , N. Przybilla , S. Geier , M. Prvák , J. Krtička , R. H. Østensen , J. Telting , K. Werner

We review at length the longstanding problem in the spectroscopic analysis of cool hydrogen-line (DA) white dwarfs (Teff < 13,000 K) where gravities are significantly higher than those found in hotter DA stars. The first solution that has…

Solar and Stellar Astrophysics · Physics 2015-05-18 P. -E. Tremblay , P. Bergeron , J. S. Kalirai , A. Gianninas

It has been suggested that the absence of macroturbulence in the atmosphere of NGC 1624 - 2 is due its strong magnetic field (the strongest known for a massive O star) suppressing convection in its outer layers, removing the mechanism…

Solar and Stellar Astrophysics · Physics 2019-06-19 James MacDonald , Véronique Petit

We present new spectroscopic and photometric measurements of the white dwarfs LHS 3250 and WD 0346+246. Along with F351-50, these white dwarfs are the coolest ones known, all with effective temperatures below 4000 K. Their membership in the…

Precision modeling of M dwarfs has become worthwhile in recent years due to the increasingly precise values of masses and radii which can be obtained from eclipsing binary studies. Torres (2013) has identified 4 prime M dwarf pairs with the…

Solar and Stellar Astrophysics · Physics 2013-11-14 James MacDonald , Dermott Mullan

There are no known examples of magnetic white dwarfs with fields larger than about 3MG paired with a non-degenerate companion in detached binary systems. The suggestion is that highly magnetic, isolated white dwarfs may originate from stars…

Solar and Stellar Astrophysics · Physics 2016-01-18 Lilia Ferrario

The article covers the physical properties and evolution of single white dwarfs ranging in temperature from 20,000K to 200,000 and higher, the hottest know electron-degenerate stars. After discussing the classification of their spectra, the…

Solar and Stellar Astrophysics · Physics 2011-11-30 Edward M. Sion

We present the first direct magnetic field measurements on M dwarfs cooler than spectral class M4.5. Utilizing a new method based on the effects of a field on the FeH band near 1 micron, we obtain information on whether the integrated…

Astrophysics · Physics 2008-11-26 A. Reiners , G. Basri

Under the assumption of a specific nonminimal coupling of torsion to Under the assumption of a specific nonminimal coupling of torsion to electromagnetism, spacetime is birefringent in the presence of a gravitational field leading to…

Astrophysics · Physics 2007-05-23 Oliver Preuss , Stefan Jordan , Mark P. Haugan , Sami K. Solanki

Magnetic configurations, stable on the long term, appear to exist in various evolutionary phases, from Main-Sequence stars to white dwarfs and neutron stars. The large scale ordered nature of these fields, often approximately dipolar, and…

Solar and Stellar Astrophysics · Physics 2015-06-22 Andre Maeder , Georges Meynet

White dwarfs represent the last stage of evolution of stars with mass less than about eight times that of the Sun and, like other stars, are often found in binaries. If the orbital period of the binary is short enough, energy losses from…

White dwarfs carry information on the structure and evolution of the Galaxy, especially through their luminosity function and initial-to-final mass relation. Very cool white dwarfs provide insight into the early ages of each population.…