Binaries discovered by the SPY project I. HE 1047-0436: a subdwarf B + white dwarf system

Abstract

In the course of our search for double degenerate binaries as potential progenitors of type Ia supernovae with the UVES spectrograph at the ESO VLT (ESO SN Ia Progenitor surveY - SPY) we discovered that the sdB star HE 1047-0436 is radial velocity variable. The orbital period of 1.213253d, a semi-amplitude of 94km/s, and a minimum mass of the invisible companion of 0.44Msol are derived from the analysis of the radial velocity curve. We use an upper limit on the projected rotational velocity of the sdB star to constrain the system inclination and the companion mass to M>0.71Msol, bringing the total mass of the system closer to the Chandrasekhar limit. However, the system will merge due to loss of angular momentum via gravitational wave radiation only after several Hubble times. Atmospheric parameters and metal abundances are also derived. The resulting values are typical for sdB stars.

A&A Letters, accepted, 4 pages, 5 figures

References in corpus (10)

• Observational Evidence from Supernovae for an Accelerating Universe and a Cosmological Constant
• Ultraviolet Radiation from Evolved Stellar Populations -- I. Models
• The binary fraction of extreme horizontal branch stars
• KPD1930+2752 - a candidate Type Ia supernova progenitor
• A Comparative Study of the Mass Distribution of Extreme Ultraviolet-Selected White Dwarfs
• Close Binary White Dwarf Systems: Numerous New Detections and Their Interpretation
• The stellar content of the Hamburg/ESO survey. I. Automated selection of DA white dwarfs
• The fraction of double degenerates among DA white dwarfs
• Detached white-dwarf close-binary stars -- CV's extended family
• Is KPD 1930+2752 a good SN Ia progenitor?

Cited by in corpus (32)

• The origin of sdB stars (II)
• Hot subluminous stars
• A binary model for the UV-upturn of elliptical galaxies (MNRAS version)
• Close binary EHB stars from SPY
• Orbital periods of twenty two subdwarf B stars
• The ELM Survey. II. Twelve Binary White Dwarf Merger Systems
• The hot subdwarf B + white dwarf binary KPD 1930+2752 - a Supernova Type Ia progenitor candidate
• Search for progenitors of supnernovae type Ia with SPY
• Hot subdwarf binaries from the MUCHFUSS project - Analysis of 12 new systems and a study of the short-period binary population
• The ELM Survey. IV. 24 White Dwarf Merger Systems
• Binaries discovered by the SPY project. IV. Five single-lined DA double white dwarfs
• The MUCHFUSS project - Searching for hot subdwarf binaries with massive unseen companions: Survey, target selection and atmospheric parameters
• The ESO supernovae type Ia progenitor survey (SPY)
• On the Formation of Double White Dwarfs through Stable Mass Transfer and a Common Envelope
• Hot subdwarf stars in close-up view I. Rotational properties of subdwarf B stars in close binary systems and nature of their unseen companions
• A survey for pulsating subdwarf B stars with the Nordic Optical Telescope
• The Discovery of Binary White Dwarfs that will Merge within 500 Myr
• New binaries among UV-selected, hot subdwarf stars and population properties
• Six detached white-dwarf close binaries
• Modelling the formation of double white dwarfs
• Hot subdwarf stars in close-up view - III. Metal abundances of subdwarf B stars
• Binaries discovered by the SPY project. II. HE 1414-0848: a double degenerate with a mass close to the Chandrasekhar limit
• A Catalogue of Potential Post Common Envelope Binaries
• High resolution spectroscopy of bright subdwarf B stars - I. Radial velocity variables
• A Spectroscopic Analysis of Blue Stragglers, Horizontal Branch and Turn-Off Stars in Four Globular Clusters
• Chandra X-ray Sources in the Collapsed-Core Globular Cluster M30 (NGC 7099)
• Binaries discovered by the SPY project. III. HE2209-1444: a massive, short period double degenerate
• Binaries discovered by the SPY project V. GD 687 - a massive double degenerate binary progenitor that will merge within a Hubble time
• SDSS J163030.58+423305.8: A 40 minute Orbital Period Detached White Dwarf Binary
• A Comparative Study of Optical and Ultraviolet Effective Temperatures for DA White Dwarfs from the IUE Archive
• Atmospheric parameters and abundances of sdB stars
• Binaries discovered by the SPY survey VI. Discovery of a low mass companion to the hot subluminous planetary nebula central star EGB\,5 - A recently ejected common envelope?