Evidence of enhanced magnetism in cool, polluted white dwarfs

Adela Kawka; Stéphane Vennes; Lilia Ferrario; Ernst Paunzen

doi:10.1093/mnras/sty3048

Evidence of enhanced magnetism in cool, polluted white dwarfs

Adela Kawka^*, Stéphane Vennes, Lilia Ferrario, Ernst Paunzen

^*Corresponding author for this work

Research output: Contribution to journal › Article › peer-review

35 Citations (Scopus)

Abstract

We report the discovery of a new, polluted, magnetic white dwarf in the Luyten survey of high-proper motion stars. High-dispersion spectra of NLTT 7547 reveal a complex heavy element line spectrum in a cool (≈5200 K) hydrogen-dominated atmosphere showing the effect of a surface averaged field of 163 kG, consistent with a 240 kG centred dipole, although the actual field structure remains uncertain. The abundance pattern shows the effect of accreted material with a distinct magnesium-rich flavour. Combined with earlier identifications, this discovery supports a correlation between the incidence of magnetism in cool white dwarfs and their contamination by heavy elements.

Original language	English
Pages (from-to)	5201-5210
Number of pages	10
Journal	Monthly Notices of the Royal Astronomical Society
Volume	482
Issue number	4
DOIs	https://doi.org/10.1093/mnras/sty3048
Publication status	Published - 1 Feb 2019

Access to Document

10.1093/mnras/sty3048

Cite this

@article{d35d35d4187d466eae5a12b6444e0917,

title = "Evidence of enhanced magnetism in cool, polluted white dwarfs",

abstract = "We report the discovery of a new, polluted, magnetic white dwarf in the Luyten survey of high-proper motion stars. High-dispersion spectra of NLTT 7547 reveal a complex heavy element line spectrum in a cool (≈5200 K) hydrogen-dominated atmosphere showing the effect of a surface averaged field of 163 kG, consistent with a 240 kG centred dipole, although the actual field structure remains uncertain. The abundance pattern shows the effect of accreted material with a distinct magnesium-rich flavour. Combined with earlier identifications, this discovery supports a correlation between the incidence of magnetism in cool white dwarfs and their contamination by heavy elements.",

keywords = "Stars: abundances, Stars: individual: NLTT 7547, Stars: magnetic field, White dwarfs",

author = "Adela Kawka and St{\'e}phane Vennes and Lilia Ferrario and Ernst Paunzen",

note = "Publisher Copyright: {\textcopyright} 2018 The Author(s).",

year = "2019",

month = feb,

day = "1",

doi = "10.1093/mnras/sty3048",

language = "English",

volume = "482",

pages = "5201--5210",

journal = "Monthly Notices of the Royal Astronomical Society",

issn = "0035-8711",

publisher = "Oxford University Press ",

number = "4",

}

TY - JOUR

T1 - Evidence of enhanced magnetism in cool, polluted white dwarfs

AU - Kawka, Adela

AU - Vennes, Stéphane

AU - Ferrario, Lilia

AU - Paunzen, Ernst

PY - 2019/2/1

Y1 - 2019/2/1

N2 - We report the discovery of a new, polluted, magnetic white dwarf in the Luyten survey of high-proper motion stars. High-dispersion spectra of NLTT 7547 reveal a complex heavy element line spectrum in a cool (≈5200 K) hydrogen-dominated atmosphere showing the effect of a surface averaged field of 163 kG, consistent with a 240 kG centred dipole, although the actual field structure remains uncertain. The abundance pattern shows the effect of accreted material with a distinct magnesium-rich flavour. Combined with earlier identifications, this discovery supports a correlation between the incidence of magnetism in cool white dwarfs and their contamination by heavy elements.

AB - We report the discovery of a new, polluted, magnetic white dwarf in the Luyten survey of high-proper motion stars. High-dispersion spectra of NLTT 7547 reveal a complex heavy element line spectrum in a cool (≈5200 K) hydrogen-dominated atmosphere showing the effect of a surface averaged field of 163 kG, consistent with a 240 kG centred dipole, although the actual field structure remains uncertain. The abundance pattern shows the effect of accreted material with a distinct magnesium-rich flavour. Combined with earlier identifications, this discovery supports a correlation between the incidence of magnetism in cool white dwarfs and their contamination by heavy elements.

KW - Stars: abundances

KW - Stars: individual: NLTT 7547

KW - Stars: magnetic field

KW - White dwarfs

UR - https://www.scopus.com/pages/publications/85061083925

U2 - 10.1093/mnras/sty3048

DO - 10.1093/mnras/sty3048

M3 - Article

SN - 0035-8711

VL - 482

SP - 5201

EP - 5210

JO - Monthly Notices of the Royal Astronomical Society

JF - Monthly Notices of the Royal Astronomical Society

IS - 4

ER -

Evidence of enhanced magnetism in cool, polluted white dwarfs

Abstract

Access to Document

Other files and links

Fingerprint

Cite this