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Related papers: The cool magnetic DAZ white dwarf NLTT 10480

200 papers

<b>Aims:</b> We analyse the magnetic field geometry of the magnetic DA white dwarf PG 1015+014 with our Zeeman tomography method.<br> <b>Methods:</b> This study is based on rotation-phase resolved optical flux and circular polarization…

Astrophysics · Physics 2016-08-15 F. Euchner , S. Jordan , K. Beuermann , K. Reinsch , B. T. Gaensicke

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

White dwarfs are excellent research laboratories as they reach temperatures, pressures, and magnetic fields that are unattainable on Earth. To better understand how these three physical parameters interact with each other and with other…

Solar and Stellar Astrophysics · Physics 2023-02-22 L. L. Amorim , S. O. Kepler , Baybars Külebi , S. Jordan , A. D. Romero

Magnetic fields in cool stars can be investigated by measuring Zeeman line broadening and polarization in atomic and molecular lines. Similar to the Sun, these fields are complex and height-dependent. Many molecular lines dominating M-dwarf…

Solar and Stellar Astrophysics · Physics 2019-09-11 N. Afram , S. V. Berdyugina

We used the revised New Luyten Two-Tenths (rNLTT) catalog to select high proper motion white dwarf candidates. We studied the spectra of 70 hydrogen-rich (DA) white dwarfs, which were obtained at the Cerro Tololo Inter-American Observatory…

Solar and Stellar Astrophysics · Physics 2009-01-20 E. Arazimova , A. Kawka , S. Vennes

We report the identification of SDSS J121929.45+471522.8 as the third apparently isolated magnetic (B~18.5+/-1.0,MG) white dwarf exhibiting Zeeman-split Balmer emission lines. The star shows coherent variability at optical wavelengths with…

Context: About 10% of white dwarfs have magnetic fields with strength in the range between about 10^5 and 3x10^8 G. It is not known whether the remaining white dwarfs are not magnetic, or if they have a magnetic field too weak to be…

Solar and Stellar Astrophysics · Physics 2015-06-11 J. D. Landstreet , S. Bagnulo , G. G. Valyavin , L. Fossati , S. Jordan , D. Monin , G. Wade

We present the results of a search for cool white dwarfs in the United Kingdom InfraRed Telescope (UKIRT) Infrared Deep Sky Survey (UKIDSS) Large Area Survey (LAS). The UKIDSS LAS photometry was paired with the Sloan Digital Sky Survey…

Solar and Stellar Astrophysics · Physics 2015-05-27 S. K. Leggett , N. Lodieu , P. -E. Tremblay , P. Bergeron , A. Nitta

We performed an optical study of the magnetic period-bouncer candidate IL Leo. Long-term photometric analysis over $\approx 20$ years reveals multiple state transitions. Modelling the ultraviolet and optical spectral energy distribution…

Solar and Stellar Astrophysics · Physics 2026-03-13 M. V. Suslikov , A. I. Kolbin , N. V. Borisov

White dwarfs with metal lines in their spectra act as signposts for post-main sequence planetary systems. Searching the Sloan Digital Sky Survey (SDSS) data release 12, we have identified 231 cool (<9000 K) DZ white dwarfs with strong metal…

Solar and Stellar Astrophysics · Physics 2017-02-08 Mark Hollands , Detlev Koester , Vadim Alekseev , Emma Herbert , Boris T. Gaensicke

We present a spectroscopic survey of 230 white dwarf candidates within 40 pc of the Sun from the William Herschel Telescope and Gran Telescopio Canarias. All candidates were selected from $\textit{Gaia}$ Data Release 2 (DR2) and in almost…

The small DAHe and DAe spectral classes comprise isolated, hydrogen-dominated atmosphere white dwarfs that exhibit variable photometric flux and Balmer line emission. These mysterious systems offer unique insight into the complex interplay…

We present an analysis of spectroscopic data of the cool, highly magnetic and polluted white dwarf 2MASS J0916-4215. The atmosphere of the white dwarf is dominated by hydrogen, but numerous spectral lines of magnesium, calcium, titanium,…

Solar and Stellar Astrophysics · Physics 2023-11-15 Stephane Vennes , Adela Kawka , Beth L. Klein , B. Zuckerman , Alycia J. Weinberger , Carl Melis

We present a detailed model atmosphere analysis of high-dispersion and high signal-to-noise ratio spectra of the heavily polluted DAZ white dwarf GALEX J1931+0117. The spectra obtained with the VLT-Kueyen/UV-Visual Echelle Spectrograph show…

Solar and Stellar Astrophysics · Physics 2015-05-27 S. Vennes , A. Kawka , P. Nemeth

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

During the low optical brightness states of AM Herculis systems (polars) when accretion has declined to a very low value, the underlying magnetic white dwarf photosphere can be modelled without the complication of thermal bremstrahlung and…

Astrophysics · Physics 2007-05-23 Edward Michael Sion

Fifty-two magnetic white dwarfs have been identified in spectroscopic observations from the Sloan Digital Sky Survey (SDSS) obtained between mid-2002 and the end of 2004, including Data Releases 2 and 3. Though not as numerous nor as…

We have paired the Second Data Release of the Large Area Survey of the UKIRT Infrared Deep Sky Survey with the Fifth Data Release of the Sloan Digital Sky Survey to identify ten cool white dwarf candidates, from their photometry and…

Astrophysics · Physics 2014-11-18 N. Lodieu , S. K. Leggett , P. Bergeron , A. Nitta

The atmospheres of very cool, hydrogen-rich white dwarfs (Teff <6000 K) are challenging to models because of the increased complexity of the equation of state, chemical equilibrium, and opacity sources in a low-temperature, weakly ionized…

Solar and Stellar Astrophysics · Physics 2015-06-22 D. Saumon , J. B. Holberg , P. M. Kowalski

We present the discovery of an unusual, tidally-distorted extremely low mass white dwarf (WD) with nearly solar metallicity. Radial velocity measurements confirm that this is a compact binary with an orbital period of 2.6975 hrs and a…

Solar and Stellar Astrophysics · Physics 2015-06-18 A. Gianninas , J. J. Hermes , Warren R. Brown , P. Dufour , Sara D. Barber , Mukremin Kilic , Scott J. Kenyon , Samuel T. Harrold