Photometric follow-up of 43 new eclipsing white dwarf plus main-sequence binaries from the ZTF survey

Abstract

Wide-field time-domain photometric sky surveys are now finding hundreds of eclipsing white dwarf plus M dwarf binaries, a population encompassing a wealth of information and potential insight into white dwarf and close binary astrophysics. Precise follow-up observations are essential in order to fully constrain these systems and capitalise on the power of this sample. We present the first results from our program of high-speed, multi-band photometric follow-up. We develop a method to measure temperatures, (model-dependent) masses, and radii for both components from the eclipse photometry alone and characterize 34 white dwarf binaries, finding general agreement with independent estimates using an alternative approach while achieving around a factor of two increase in parameter precision. In addition to these parameter estimates, we discover a number of interesting systems -- finding four with sub-stellar secondaries, doubling the number of eclipsing examples, and at least six where we find the white dwarf to be strongly magnetic, making these the first eclipsing examples of such systems and key to investigating the mechanism of magnetic field generation in white dwarfs. We also discover the first two pulsating white dwarfs in detached and eclipsing post-common-envelope binaries -- one with a low-mass, likely helium core, and one with a relatively high mass, towards the upper end of the known sample of ZZ Cetis. Our results demonstrate the power of eclipse photometry, not only as a method of characterising the population, but as a way of discovering important systems that would have otherwise been missed by spectroscopic follow-up.

12 pages with a 5 page appendix and 14 figures. Accepted for publication in MNRAS

References in corpus (28)

• The Gaia mission
• The Zwicky Transient Facility: System Overview, Performance, and First Results
• New evolutionary models for pre-main sequence and main sequence low-mass stars down to the hydrogen-burning limit
• The Zwicky Transient Facility: Data Processing, Products, and Archive
• The Zwicky Transient Facility: Science Objectives
• The Evolution of L and T Dwarfs in Color-Magnitude Diagrams
• A Catalog of Multiplicity among Bright Stellar Systems
• Pulsating White Dwarf Stars and Precision Asteroseismology
• ULTRACAM: an ultra-fast, triple-beam CCD camera for high-speed astrophysics
• On the Spectral Evolution of Hot White Dwarf Stars. I. A Detailed Model-Atmosphere Analysis of Hot White Dwarfs from SDSS DR12
• A Giant Planet Candidate Transiting a White Dwarf
• Post Common Envelope Binaries from SDSS. I: 101 white dwarf main sequence binaries with multiple SDSS spectroscopy
• Testing the white dwarf mass-radius relationship with eclipsing binaries
• A Volume-Limited Sample of Ultracool Dwarfs. I. Construction, Space Density, and a Gap in the L/T Transition
• HiPERCAM: a quintuple-beam, high-speed optical imager on the 10.4-m Gran Telescopio Canarias
• White dwarf-main sequence binaries from Gaia EDR3: the unresolved 100pc volume-limited sample
• Two white dwarfs in ultrashort binaries with detached, eclipsing, likely substellar companions detected by K2
• The substellar companion in the eclipsing white dwarf binary SDSS J141126.20+200911.1
• Fourteen new eclipsing white dwarf plus main-sequence binaries from the SDSS and Catalina surveys
• Discovery of 74 new bright ZZ Ceti stars in the first three years of TESS
• WD1032+011, an inflated brown dwarf in an old eclipsing binary with a white dwarf
• The white dwarf binary pathways survey - II. Radial velocities of 1453 FGK stars with white dwarf companions from LAMOST DR4
• Magnetic white dwarfs in post-common-envelope binaries
• The White Dwarf Binary Pathways Survey VI: two close post common envelope binaries with TESS light curves
• Characterising eclipsing white dwarf M dwarf binaries from multi-band eclipse photometry
• Discovery of ZZ Cetis in detached white dwarf plus main-sequence binaries
• Four new deeply-eclipsing white dwarfs in ZTF
• Doppler beaming factors for white dwarfs, main sequence stars, and giant stars Limb-darkening coefficients for 3D (DA and DB) white dwarf models

Cited by in corpus (10)

• Forming merging double compact objects with stable mass transfer
• Formation of long-period post-common-envelope binaries II. Explaining the self-lensing binary KOI 3278
• On the optical transients from double white-dwarf mergers
• A population synthesis study of the Gaia 100 pc unresolved white dwarf-main sequence binary population
• Reconstructing post-common envelope white dwarf+main sequence binary histories through inverse population synthesis techniques
• A magnitude-limited catalogue of unresolved white dwarf-main sequence binaries from Gaia DR3
• Extreme mass loss during common envelope evolution: the origin of the double low-mass white dwarf system J2102--4145
• Searching for new variable white dwarfs: The discovery of the three new pulsating and three new binary systems
• FINKER: Frequency Identification through Nonparametric KErnel Regression in astronomical time series
• NGTS-EB-8: A double-lined eclipsing M+M binary discovered by citizen scientists