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Related papers: Magnetic White Dwarfs with Heavy Elements

200 papers

In this work we compute models for relativistic white dwarfs in the presence of strong magnetic fields. These models possibly contribute to super-luminous SNIa. With an assumed axi-symmetric and poloidal magnetic field, we study the…

Solar and Stellar Astrophysics · Physics 2015-10-21 Bruno Franzon , Stefan Schramm

In the vast expanse of our galaxy, white dwarfs (WDs) are natural sentinels, capturing the enigmatic dark matter (DM) particles that incessantly traverse their interiors. These celestial bodies provide a unique vantage point for probing…

High Energy Physics - Phenomenology · Physics 2024-06-06 Jia-Shu Niu

We investigate whether the recently suggested rotation and crystallization driven dynamo can explain the apparent increase of magnetism in old metal polluted white dwarfs. We find that the effective temperature distribution of polluted…

Solar and Stellar Astrophysics · Physics 2021-07-14 Matthias R. Schreiber , Diogo Belloni , Boris T. Gaensicke , Steven G. Parsons

We present PHOENIX atmosphere models for metal-rich cool white dwarfs using improved line shapes for the Na I and K I resonance doublets. Profiles for collisional broadening due to H2 and He based on the adiabatic representation show strong…

Following our recent discovery of a new magnetic DQ white dwarf (WD) with CH molecular features, we report the results for the rest of the DQ WDs from our survey. We use high signal-to-noise spectropolarimetric data to search for magnetic…

Solar and Stellar Astrophysics · Physics 2013-08-27 Tommi Vornanen , Svetlana Berdyugina , Andrei Berdyugin

We present an analysis of photometric, spectroscopic and spectropolarimetric data of the nearby, cool, magnetic DZ white dwarf PM J08186-3110. High dispersion spectra show the presence of Zeeman splitted spectral lines due to the presence…

Solar and Stellar Astrophysics · Physics 2020-11-11 Adela Kawka , Stéphane Vennes , Nicole F. Allard , T. Leininger , F. X. Gadéa

We present a detailed model atmosphere analysis of massive white dwarfs with $M > 0.9~M_\odot$ and $T_{\rm eff}\geq11,000$ K in the Montreal White Dwarf Database 100 pc sample and the Pan-STARRS footprint. We obtained follow-up optical…

We clarify important physics issues related to the recently established new mass limit for magnetized white dwarfs which is significantly super-Chandrasekhar. The issues include, justification of high magnetic field and the corresponding…

Solar and Stellar Astrophysics · Physics 2014-06-05 Upasana Das , Banibrata Mukhopadhyay

A sequence of pure-hydrogen CO5BOLD 3D model atmospheres of DA white dwarfs is presented for a surface gravity of log g = 8 and effective temperatures from 6000 to 13,000 K. We show that convective properties, such as flow velocities,…

Solar and Stellar Astrophysics · Physics 2015-06-15 P. -E. Tremblay , H. -G. Ludwig , M. Steffen , B. Freytag

The magnetic white dwarfs (MWDs) are found either isolated or in interacting binaries. They divide into two groups: a high field group (0.1-1,000MegaGauss) comprising some 13% of all white dwarfs (WDs), and a low field group (B<0.1MG) whose…

Solar and Stellar Astrophysics · Physics 2020-01-29 Lilia Ferrario , D. T. Wickramasinghe , Adela Kawka

We investigate the luminosity and cooling of highly magnetized white dwarfs where cooling occurs by the diffusion of photons. We solve the magnetostatic equilibrium and photon diffusion equations to obtain the temperature and density…

Solar and Stellar Astrophysics · Physics 2018-10-19 Mukul Bhattacharya , Banibrata Mukhopadhyay , Subroto Mukerjee

The hard X-ray spectrum of magnetic cataclysmic variables can be modelled to provide a measurement of white dwarf mass. This method is complementary to radial velocity measurements, which depend on the (typically rather uncertain) binary…

In this work, we study the properties of magnetized white dwarfs taking into account possible instabilities due to electron capture and pycnonuclear fusion reactions in the cores of such objects. The structure of white dwarfs is obtained by…

Solar and Stellar Astrophysics · Physics 2017-03-31 Edson Otoniel , Bruno Franzon , Manuel Malheiro , Stefan Schramm , Fridolin Weber

We study ultralight scalar fields with quadratic couplings to Standard-Model fermions and derive strong constraints from white-dwarf mass-radius data. Such couplings source scalar profiles inside compact stars, shift fermion masses, and can…

High Energy Physics - Phenomenology · Physics 2026-05-18 Kai Bartnick , Konstantin Springmann , Stefan Stelzl , Andreas Weiler

We investigate isolated sub- and super-Chandrasekhar white dwarfs which lose angular momentum through magnetic dipole braking. We construct constant rest mass sequences by fulfilling all stability criteria of rotating configurations and…

Solar and Stellar Astrophysics · Physics 2016-04-11 Kuantay Boshkayev , Jorge A. Rueda , Remo Ruffini , Bakytzhan Zhami

Magnetic white dwarfs with field strengths below 10 MG are easy to recognise since the Zeeman splitting of spectral lines appears proportional to the magnetic field strength. For fields $\geq 100$ MG, however, transition wavelengths become…

Solar and Stellar Astrophysics · Physics 2023-01-25 Mark A. Hollands , Stella Stopkowicz , Marios-Petros Kitsaras , Florian Hampe , Simon Blaschke , J. J. Hermes

We present first quantitative results of the surface magnetic field measurements in selected M-dwarfs based on detailed spectra synthesis conducted simultaneously in atomic and molecular lines of the FeH Wing-Ford $F^4\,\Delta-X^4\,\Delta$…

Solar and Stellar Astrophysics · Physics 2015-05-19 D. Shulyak , A. Reiners , S. Wende , O. Kochukhov , N. Piskunov , A. Seifahrt

We present a critical review of the determination of fundamental parameters of white dwarfs discovered by the Gaia mission. We first reinterpret color-magnitude and color-color diagrams using photometric and spectroscopic information…

Solar and Stellar Astrophysics · Physics 2019-05-15 P. Bergeron , P. Dufour , G. Fontaine , S. Coutu , S. Blouin , C. Genest-Beaulieu , A. Bédard , B. Rolland

In recent years a number of white dwarfs has been observed with very high surface magnetic fields. We can expect that the magnetic field in the core of these stars would be much higher (~ 10^{14} G). In this paper, we analytically study the…

Solar and Stellar Astrophysics · Physics 2012-05-09 Aritra Kundu , Banibrata Mukhopadhyay

To date, pulsational variability has been measured from nearly 70 DBVs and 500 DAVs, with only a fraction of these having been the subjects of asteroseismic analysis. One way to approach white dwarf asteroseismology is forward modeling,…

Solar and Stellar Astrophysics · Physics 2023-08-09 Agnes Bischoff-Kim