Modified pulsar current analysis: probing magnetic field evolution

Abstract

We use a modified pulsar current analysis to study magnetic field decay in radio pulsars. In our approach we analyse the flow, not along the spin period axis as has been performed in previous studies, but study the flow along the direction of growing characteristic age, $\tau =P/(2\dot{P})$. We perform extensive tests of the method and find that in most of the cases it is able to uncover non-negligible magnetic field decay (more than a few tens of per cent during the studied range of ages) in normal radio pulsars for realistic initial properties of neutron stars. However, precise determination of the magnetic field decay timescale is not possible at present. The estimated timescale may differ by a factor of few for different sets of initial distributions of neutron star parameters. In addition, some combinations of initial distributions and/or selection effects can also mimic enhanced field decay. We apply our method to the observed sample of radio pulsars at distances $<10$ kpc in the range of characteristic ages $8\times 10^4<\tau <10^6$ years where, according to our study, selection effects are minimized. By analysing pulsars in the Parkes Multibeam and Swinburne surveys we find that, in this range, the field decays roughly by a factor of two. With an exponential fit this corresponds to the decay time scale $\sim 4\times 10^5$ yrs. With larger statistics and better knowledge of the initial distribution of spin periods and magnetic field strength, this method can be a powerful tool to probe magnetic field decay in neutron stars.

Accepted for publication in MNRAS. 11 pages, 11 figures

References in corpus (24)

• The ATNF Pulsar Catalogue
• The ATNF Pulsar Catalogue
• Time-dependent force-free pulsar magnetospheres: axisymmetric and oblique rotators
• Birth and Evolution of Isolated Radio Pulsars
• The Parkes Multibeam Pulsar Survey: I. Observing and Data Analysis Systems, Discovery and Timing of 100 Pulsars
• Unifying the observational diversity of isolated neutron stars via magneto-thermal evolution models
• Magnetic Field Evolution in Neutron Star Crusts due to the Hall Effect and Ohmic Decay
• 2D Cooling of Magnetized Neutron Stars
• Time evolution of pulsar obliquity angle from 3D simulations of magnetospheres
• Population synthesis studies of isolated neutron stars with magnetic field decay
• Physical Mechanisms for the Variable Spin-down of SGR 1900+14
• PSR J1847-0130: A Radio Pulsar with Magnetar Spin Characteristics
• Initial spin periods of neutron stars in supernova remnants
• Galactic populations of radio and gamma-ray pulsars in the polar cap model
• The Crustal Rigidity of a Neutron Star, and Implications for PSR 1828-11 and other Precession Candidates
• Neutron stars initial spin period distribution
• Population synthesis in astrophysics
• Radio pulsars: the search for truth
• Magnetic field estimates for accreting neutron stars in massive binary systems and models of magnetic field decay
• Evolution of isolated neutron stars till accretion. The role of initial magnetic field
• Pulsar current revisited
• Unifying neutron stars: getting to GUNS
• A Theoretical Study of the Magnetically Deformed Inner Crust Matter of Magnetars
• The Study of Magnetically Deformed Atoms in the Outer Crust of Neutron Stars in Presence of Strong Quantizing Magnetic Field

Cited by in corpus (20)

• Magnetic field growth in young glitching pulsars with a braking index
• Radio pulsars: already fifty years!
• Hall drift and the braking indices of young pulsars
• Gravitational Waves from Pulsars and Their Braking Indices: The Role of a Time Dependent Magnetic Ellipticity
• 3D Magneto-thermal Simulations of Tangled Crustal Magnetic Field in Central Compact Objects
• Magnetic field evolution timescales in superconducting neutron stars
• Ages of radio pulsar: long-term magnetic field evolution
• Magnetic Field Evolution in Neutron Star Crusts: Beyond the Hall Effect
• Braking indices of young radio pulsars: theoretical perspective
• On the Diversity of Compact Objects within Supernova Remnants. I: A Parametric Model for Magnetic Field Evolution
• Gravitational waves from pulsars with measured braking index
• The influence of quantum vacuum friction on pulsars
• Probing the surface magnetic field structure in RX J1856.5-3754
• On the second derivatives of periods and braking indices in radio pulsars
• On the Diversity of Compact Objects within Supernova Remnants II: Energy Loss Mechanisms
• Looking for Hall attractor in astrophysical sources
• The effective magnetic field decay of radio pulsars: insights from the statistical properties of their spin frequency's second derivatives
• Imprint of magnetic obliquity in apparent spin-down of radio pulsars
• The apparent decay of pulsar magnetic fields
• Magnetic field decay in young radio pulsars