The Nature of Millisecond Pulsars with Helium White Dwarf Companions

Abstract

We examine the growing data set of binary millisecond pulsars that are thought to have a helium white dwarf companion. These systems are believed to form when a low- to intermediate-mass companion to a neutron star fills its Roche lobe between central hydrogen exhaustion and core helium ignition. We confirm that our own stellar models reproduce a well-defined period-companion mass relation irrespective of the details of the mass transfer process. With magnetic braking this relation extends to periods of less than 1d for a 1Msun giant donor. With this and the measured binary mass functions we calculate the orbital inclination of each system for a given pulsar mass. We expect these inclinations to be randomly oriented in space. If the masses of the pulsars were typically 1.35Msun then there would appear to be a distinct dearth of high-inclination systems. However if the pulsar masses are more typically 1.55 to 1.65Msun then the distribution of inclinations is indeed indistinguishable from random. If it were as much as 1.75Msun then there would appear to be an excess of high-inclination systems. Thus with the available data we can argue that the neutron star masses in binary millisecond pulsars recycled by mass transfer from a red giant typically lie around 1.6Msun and that there is no preferred inclination at which these systems are observed. Hence there is reason to believe that pulsar beams are either sufficiently broad or show no preferred direction relative to the pulsar's spin axis which is aligned with the binary orbit. This is contrary to some previous claims, based on a subset of the data available today, that there might be a tendency for the pulsar beams to be perpendicular to their spin.

arXiv commentAccepted by MNRAS

References in corpus (23)

• Shapiro delay measurement of a two solar mass neutron star
• A Massive Pulsar in a Compact Relativistic Binary
• The ATNF Pulsar Catalogue
• The ATNF Pulsar Catalogue
• Low Temperature Opacities
• Neutron Star Mass Measurements. I. Radio Pulsars
• Binary and Millisecond Pulsars
• Approximate input physics for stellar modelling
• Evolutionary Binary Sequences for Low- and Intermediate-Mass X-ray Binaries
• Swings between rotation and accretion power in a millisecond binary pulsar
• Precision timing of PSR J0437-4715: an accurate pulsar distance, a high pulsar mass and a limit on the variation of Newton's gravitational constant
• Study of measured pulsar masses and their possible conclusions
• Modelling the binary progenitor of supernova 1993J
• The relativistic pulsar-white dwarf binary PSR J1738+0333 I. Mass determination and evolutionary history
• Masses, Parallax, and Relativistic Timing of the PSR J1713+0747 Binary System
• Further Evidence for the Bimodal Distribution of Neutron Star Masses
• Masses and orbital inclinations of planets in the PSR B1257+12 system
• High-Precision Timing of 5 Millisecond Pulsars: Space Velocities, Binary Evolution and Equivalence Principles
• Discovery of Three Wide-orbit Binary Pulsars: Implications for Binary Evolution and Equivalence Principles
• A Code for Stellar Binary Evolution and its Application to the Formation of Helium White Dwarfs
• Formation of Millisecond Pulsars from Intermediate- and Low-Mass X-ray Binaries
• A Shapiro delay detection in the binary system hosting the millisecond pulsar PSR J1910-5959A
• The evolution of low mass, close binary systems with a neutron star component: a detailed grid

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• The Mass Distribution of Companions to Low-Mass White Dwarfs
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