Formation of the planet around the millisecond pulsar J1719-1438

Abstract

Context. Recently the discovery of PSR J1719-1438, a 5.8 ms pulsar with a companion in a 2.2 hr orbit, was reported. The combination of this orbital period and the very low mass function is unique. The discoverers, Bailes et al., proposed an ultracompact X-ray binary (UCXB) as the progenitor system. However, the standard UCXB scenario would not produce this system as the time required to reach this orbital period exceeds the current estimate of the age of the Universe. The detached state of the system aggravates the problem. Aims. We want to understand the evolutionary history of PSR J1719-1438, and determine under which circumstances it could have evolved from an UCXB. Methods. We model UCXB evolution varying the donor size and investigate the effect of a wind mass loss from the donor, and compare the results with the observed characteristics of PSR J1719-1438. Results. An UCXB can reach a 2.2 hr orbit within the age of the Universe, provided that 1) the millisecond pulsar can significantly heat and expand the donor by pulsar irradiation, or 2) the system loses extra orbital angular momentum, e.g. via a fast wind from the donor. Conclusions. The most likely scenario for the formation of PSR J1719-1438 is UCXB evolution driven by angular momentum loss via the usual gravitational wave emission, which is enhanced by angular momentum loss via a donor wind of ~3x10^-13 Msun/yr. Depending on the size of the donor during the evolution, the companion presently probably has a mass of ~1-3 Jupiter masses, making it a very low mass white dwarf as proposed by Bailes et al. Its composition can be either helium or carbon-oxygen. A helium white dwarf companion makes the long (for an UCXB) orbital period easier to explain, but the required inclination makes it a priori less likely than a carbon-oxygen white dwarf.

5 pages, 4 figures. Accepted for publication in Astronomy and Astrophysics. v2: Updated a reference

References in corpus (3)

• Orbital Evolution of an Accreting Millisecond Pulsar: Witnessing the Banquet of a Hidden Black Widow?
• Timing of the 2008 Outburst of SAX J1808.4-3658 with XMM-Newton: A Stable Orbital Period Derivative over Ten Years
• Accretion of helium and metal-rich gas onto neutron stars and black holes at high luminosities

Cited by in corpus (21)

• A Massive Pulsar in a Compact Relativistic Binary
• Formation of millisecond pulsars with CO white dwarf companions - II. Accretion, spin-up, true ages and comparison to MSPs with He white dwarf companions
• The Green Bank Northern Celestial Cap Pulsar Survey - I: Survey Description, Data Analysis, and Initial Results
• Binary Millisecond Pulsar Discovery via Gamma-Ray Pulsations
• Mass transfer in white dwarf-neutron star binaries
• Formation of millisecond pulsars with helium white dwarfs, ultra-compact X-ray binaries and gravitational wave sources
• Population synthesis of ultracompact X-ray binaries in the Galactic Bulge
• Ultra-compact X-ray binaries with He star companions
• A revisit of PSR J1909$-$3744 with 15-year high-precision timing
• Novel modelling of ultra-compact X-ray binary evolution - stable mass transfer from white dwarfs to neutron stars
• UltraCompCAT: a comprehensive Catalogue of Ultra-Compact and Short Orbital Period X-ray Binaries
• Why are pulsar planets rare?
• Long-term luminosity behavior of 14 ultracompact X-ray binaries
• A black widow population dissection through HiPERCAM multi-band light curve modelling
• Population synthesis of classical low-mass X-ray binaries in the Galactic Bulge
• Formation of black widows through ultra-compact X-ray binaries with He star companions
• Evolution of Low-Mass X-ray Binaries: the Effect of Donor Evaporation
• PSR J1953+1844 probably being the descendant of an Ultra-compact X-ray binary
• Rapid orbital expansion in millisecond pulsar PSR J0636+5128: evaporation winds?
• A tentative 114-minute orbital period challenges the ultra-compact nature of the X-ray binary 4U 1812-12
• Ultra-compact X-ray Binaries: A Review