Relativistic spin precession in the binary PSR J1141$-$6545

Abstract

PSR J1141$-$6545 is a precessing binary pulsar that has the rare potential to reveal the two-dimensional structure of a non-recycled pulsar emission cone. It has undergone $\sim 25°$ of relativistic spin precession in the $\sim 18$ years since its discovery. In this paper, we present a detailed Bayesian analysis of the precessional evolution of the width of the total intensity profile, to understand the changes to the line-of-sight impact angle ($\beta$) of the pulsar using four different physically motivated prior distribution models. Although we cannot statistically differentiate between the models with confidence, the temporal evolution of the linear and circular polarisations strongly argue that our line-of-sight crossed the magnetic pole around MJD 54000 and that only two models remain viable. For both these models, it appears likely that the pulsar will precess out of our line-of-sight in the next $3-5$ years, assuming a simple beam geometry. Marginalising over $\beta$ suggests that the pulsar is a near-orthogonal rotator and provides the first polarization-independent estimate of the scale factor ($\mathbb{A}$) that relates the pulsar beam opening angle ($\rho$) to its rotational period ($P$) as $\rho =\mathbb{A}{P}^{-0.5}$ : we find it to be $>6\mathrm{deg}{\mathrm{s}}^{0.5}$ at 1.4 GHz with 99\% confidence. If all pulsars emit from opposite poles of a dipolar magnetic field with comparable brightness, we might expect to see evidence of an interpulse arising in PSR J1141$-$6545, unless the emission is patchy.

arXiv commentAccepted for publication in Astrophysical Journal Letters

References in corpus (14)

• The Parkes Pulsar Timing Array Project
• Determination of the geometry of the PSR B1913+16 system by geodetic precession
• A Comprehensive Study of Relativistic Gravity using PSR B1534+12
• Gravitational-radiation losses from the pulsar-white-dwarf binary PSR J1141-6545
• Discovery of a Young Radio Pulsar in a Relativistic Binary Orbit
• Measurement of gravitational spin-orbit coupling in a binary pulsar system
• High-fidelity radio astronomical polarimetry using a millisecond pulsar as a polarized reference source
• Self-consistency of relativistic observables with general relativity in the white dwarf-neutron star binary pulsar PSR J1141-6545
• Observations and Modelling of Relativistic Spin Precession in PSR J1141-6545
• Long-term variations in the pulse emission from PSR J0737-3039B
• A Fan Beam Model for Radio Pulsars. I. Observational Evidence
• Geodetic Precession in PSR J1141-6545
• On the pulse--width statistics in radio pulsars. I. Importance of the interpulse emission
• The nature of pulsar radio emission

Cited by in corpus (13)

• Strong-field Gravity Tests with the Double Pulsar
• Lense-Thirring frame dragging induced by a fast-rotating white dwarf in a binary pulsar system
• Constraining the dense matter equation-of-state with radio pulsars
• Gravity experiments with radio pulsars
• The Relativistic Binary Programme on MeerKAT: Science objectives and first results
• Revisiting the Galactic Double Neutron Star merger and LIGO detection rates
• Multi-scale Constraints on Scalar-Field couplings to Matter: The Geodetic and Frame-Dragging Effects
• Revisiting profile instability of J1022+1001
• New constraints on the kinematic, relativistic and evolutionary properties of the PSR J1757$-$1854 double neutron star system
• A MeerKAT view of the double pulsar eclipses -- Geodetic precession of pulsar B and system geometry
• Improving pulsar-timing solutions through dynamic pulse fitting
• Simulations of the radio polarization of a precessing pulsar PSR J1906+0746
• A deep search for radio pulsations from the 1.3 M${}_{\odot }$ compact-object binary companion of young pulsar PSR J1906+0746