A search for kilogauss magnetic fields in white dwarfs and hot subdwarf stars

Abstract

We present new results of a survey for weak magnetic fields among DA white dwarfs with inclusion of some brighter hot subdwarf stars. We have detected variable circular polarization in the Halpha line of the hot subdwarf star Feige 34 (SP: sdO). From these data, we estimate that the longitudinal magnetic field of this star varies from -1.1 +/- 3.2 kG to +9.6 +/- 2.6 kG, with a mean of about +5 kG and a period longer than 2 h. In this study, we also confirm the magnetic nature of white dwarf WD1105-048 and present upper limits of kilogauss longitudinal magnetic fields of 5 brightest DA white dwarfs. Our data support recent finding that 25% of white dwarfs have kilogauss magnetic fields. This frequency also confirms results of early estimates obtained using the magnetic field function of white dwarfs.

arXiv commentaccepted for publication in the Astrphysical Journal

References in corpus (3)

• The True Incidence of Magnetism among Field White Dwarfs
• Discovery of kilogauss magnetic fields in three DA white dwarfs
• Discovery of magnetic fields in hot subdwarfs

Cited by in corpus (24)

• Magnetic White Dwarfs
• Can Extra Mixing in RGB and AGB Stars Be Attributed to Magnetic Mechanisms?
• Magnetic field measurements and their uncertainties: the FORS1 legacy
• The formation of high-field magnetic white dwarfs from common envelopes
• The BOES spectropolarimeter for Zeeman measurements of stellar magnetic fields
• New insight into the magnetism of degenerate stars from the analysis of a volume limited sample of white dwarfs
• On the incidence of weak magnetic fields in DA white dwarfs
• A Three-dimensional Simulation of a Magnetized Accretion Disk: Fast Funnel Accretion onto a Weakly Magnetized Star
• The pecular magnetic field morphology of the white dwarf WD 1953-011: evidence for a large-scale magnetic flux tube?
• Searching for the weakest detectable magnetic fields in white dwarfs. Highly-sensitive measurements from first VLT and WHT surveys
• Magnetic field evolution of white dwarfs in strongly interacting binary star systems
• The magnetic fields of hot subdwarf stars
• Monitoring and modelling of white dwarfs with extremely weak magnetic fields
• Asteroseismic g-mode period spacings in strongly magnetic rotating stars
• Stellar wind models of central stars of planetary nebulae
• Spectral analysis of four surprisingly similar hot hydrogen-rich subdwarf O stars
• A search for magnetic fields in cool sdB stars
• Photometric White Dwarf Rotation
• Understanding the rotational variability of K2 targets. HgMn star KIC 250152017 and blue horizontal branch star KIC 249660366
• A network of cooler white dwarfs as infrared standards for flux calibration
• Experimental study of an advanced concept of moderate-resolution holographic spectrographs
• A Binary Scenario for the Formation of Strongly Magnetized White Dwarfs
• A numerical code for the analysis of magnetic white dwarf spectra that includes field effects on the chemical equilibrium
• Discovery and analysis of three magnetic hot subdwarf stars: evidence for merger-induced magnetic fields