HD 49798: Its History of Binary Interaction and Future Evolution

Abstract

The bright subdwarf-O star (sdO), HD 49798, is in a 1.55 day orbit with a compact companion that is spinning at 13.2 seconds. Using the measurements of the effective temperature ($T_{\mathrm{eff}}$), surface gravity ($\log g$), and surface abundances of the sdO, we construct models to study the evolution of this binary system using Modules for Experiments in Stellar Astrophysics ($\text{MESA}$). Previous studies of the compact companion have disagreed on whether it is a white dwarf (WD) or a neutron star (NS). From the published measurements of the companion's spin and spin-up rate, we agree with Mereghetti and collaborators that a NS companion is more likely. However, since there remains the possibility of a WD companion, we use our constructed $\text{MESA}$ models to run simulations with both WD and NS companions that help us constrain the past and future evolution of this system. If it presently contains a NS, the immediate mass transfer evolution upon Roche lobe (RL) filling will lead to mass transfer rates comparable to that implied in ultraluminous X-ray sources (ULXs). Depending on the rate of angular momentum extraction via a wind, the fate of this system is either a wide ($P_{\mathrm{orb}}\approx 3$ day) intermediate mass binary pulsar (IMPB) with a relatively rapidly spinning NS ($\approx 0.3$ s) and a high mass WD ($\approx 0.9M_{\odot }$), or a solitary millisecond pulsar (MSP).

6 pages, 4 figures

References in corpus (23)

• Modules for Experiments in Stellar Astrophysics (MESA)
• Modules for Experiments in Stellar Astrophysics (MESA): Giant Planets, Oscillations, Rotation, and Massive Stars
• Modules for Experiments in Stellar Astrophysics (MESA): Binaries, Pulsations, and Explosions
• Discovery of a 0.42-s pulsar in the ultraluminous X-ray source NGC 7793 P13
• Discovery of coherent pulsations from the Ultraluminous X-ray Source NGC 7793 P13
• Multi-Dimensional Simulations of the Accretion-Induced Collapse of White Dwarfs to Neutron Stars
• A mass of less than 15 solar masses for the black hole in an ultraluminous X-ray source
• Puzzling accretion onto a black hole in the ultraluminous X-ray source M101 ULX-1
• He-Accreting WDs: accretion regimes and final outcomes
• Nuclear-dominated accretion and subluminous supernovae from the merger of a white dwarf with a neutron star or black hole
• Pulsing ULXs: tip of the iceberg?
• The Evolution and Fate of Super-Chandrasekhar Mass White Dwarf Merger Remnants
• An ultra-massive fast-spinning white dwarf in a peculiar binary system
• Thermal Runaway During the Evolution of ONeMg Cores towards Accretion-Induced Collapse
• The discovery of 13s X-ray pulsations from the hydrogen depleted subdwarf O6 star binary HD49798
• X-ray and optical observations of the unique binary system HD49798/RXJ0648.0-4418
• Carbon Shell or Core Ignitions in White Dwarfs Accreting from Helium Stars
• Accretion-Induced Collapse From Helium Star + White Dwarf Binaries
• Discovery of spin-up in the X-ray pulsar companion of the hot subdwarf HD 49798
• A likely candidate of type Ia supernova progenitors: the X-ray pulsating companion of the hot subdwarf HD 49798
• X-ray emission from the luminous O-type subdwarf HD 49798 and its compact companion
• Is the X-ray pulsating companion of HD 49798 a possible type Ia supernova progenitor?
• Can eccentric binary millisecond pulsars form by accretion induced collapse of white dwarfs?

Cited by in corpus (14)

• Mass-accreting white dwarfs and type Ia supernovae
• The first ultracompact Roche lobe-filling hot subdwarf binary
• A stripped helium star in the potential black hole binary LB-1
• Found: a rapidly spinning white dwarf in LAMOST J024048.51+195226.9
• Stars stripped in binaries -- the living gravitational wave sources
• The single-degenerate model for the progenitors of accretion-induced collapse events
• Evolving ONe WD+He star systems to intermediate-mass binary pulsars
• Criteria for Dynamical Timescale Mass Transfer of Metal-poor Intermediate-mass Stars
• New X-ray observations of the hot subdwarf binary HD49798 / RXJ0648.0-4418
• Off-centre carbon burning in He-accreting carbon-oxygen white dwarfs
• Hot subdwarf wind models with accurate abundances I. Hydrogen dominated stars HD 49798 and BD+18${}^{\circ }$2647
• On the X-ray pulsar HD 49798: a contracting white dwarf with debris disk?
• Timing the X-ray pulsating companion of the hot-subdwarf HD 49798 with NICER
• [HP99] 159 -- Properties of the first Supersoft X-ray Source with a Helium star donor