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Millisecond pulsars are known to show complex radio pulse profiles and polarisation position angle evolution with rotational phase. Small scale surface magnetic fields and multipolar components are believed to be responsible for this…

High Energy Astrophysical Phenomena · Physics 2025-09-03 J. Pétri , S. Guillot , L. Guillemot , D. González-Caniule , F. Jankowski , J. -M. Grießmeier , G. Theureau , I. Cognard

We present a large sample of high-precision, coherently-dedispersed polarization profiles of millisecond pulsars (MSPs) at frequencies between 410 and 1414 MHz. These data include the first polarimetric observations of several of the…

Astrophysics · Physics 2009-10-31 I. H. Stairs , S. E. Thorsett , F. Camilo

The intense magnetic fields of neutron stars naturally lead to strong anisotropy and polarization of radiation emanating from their surfaces, both being sensitive to the hot spot position on the surface. Accordingly, pulse phase-resolved…

High Energy Astrophysical Phenomena · Physics 2025-02-21 Matthew G. Baring , Hoa Dinh Thi , George A. Younes , Kun Hu

With the advent of multi-wavelength electromagnetic observations of neutron stars, spanning many decades in photon energies, from radio wavelengths up to X-rays and $\gamma$-rays, it becomes possible to significantly constrain the geometry…

Traditionally models of accretion of gas on to T Tauri stars have assumed a dipole stellar magnetosphere, partly for simplicity, but also due to the lack of information about their true magnetic field topologies. Before and since the first…

Solar and Stellar Astrophysics · Physics 2015-05-30 S. G. Gregory , J. -F. Donati

The study of magnetars is of particular relevance since these objects are the only laboratories where the physics in ultra-strong magnetic fields can be directly tested. Until now, spectroscopic and timing measurements at X-ray energies in…

High Energy Astrophysical Phenomena · Physics 2015-06-18 Roberto Taverna , Fabio Muleri , Roberto Turolla , Paolo Soffitta , Sergio Fabiani , Luciano Nobili

(abridged) Pulsar activity and its related radiation mechanism are usually explained by invoking some plasma processes occurring inside the magnetosphere. Despite many detailed local investigations, the global electrodynamics around those…

High Energy Astrophysical Phenomena · Physics 2015-06-05 J. Pétri

(Abridged) Gamma-ray emission from pulsars has long been modeled using a vacuum dipole field. This approximation ignores changes in the field structure caused by the magnetospheric plasma and strong plasma currents. We present the first…

High Energy Astrophysical Phenomena · Physics 2014-11-20 Xue-Ning Bai , Anatoly Spitkovsky

We perform first-principles relativistic particle-in-cell simulations of aligned pulsar magnetosphere. We allow free escape of particles from the surface of a neutron star and continuously populate the magnetosphere with neutral pair plasma…

High Energy Astrophysical Phenomena · Physics 2015-10-08 Alexander Philippov , Anatoly Spitkovsky

Recent modeling of Neutron Star Interior Composition Explorer(NICER) observations of the millisecond pulsar PSR J0030+0451 suggests that the magnetic field of the pulsar is non-dipolar. We construct a magnetic field configuration where foot…

High Energy Astrophysical Phenomena · Physics 2020-04-29 Alexander Y. Chen , Yajie Yuan , Georgios Vasilopoulos

We investigate the effect of pulsar polar cap (PC) heating produced by positrons returning from the upper pair formation front. Our calculations are based on a self-consistent treatment of the pair dynamics and the effect of electric field…

Astrophysics · Physics 2009-11-06 Alice K. Harding , Alexander G. Muslimov

We study the propagation effects of radio waves in a pulsar magnetosphere, composed of relativistic electron-positron pair plasmas streaming along the magnetic field lines and corotating with the pulsar. We critically examine the various…

High Energy Astrophysical Phenomena · Physics 2015-05-14 Chen Wang , Dong Lai , JinLin Han

We consider the force-free magnetosphere of an aligned rotator. Its structure is well described by a Grad-Shafranov equation for poloidal magnetic field, the so-called "pulsar equation". We solve this equation by a multigrid method with…

Astrophysics · Physics 2009-11-13 Andrey Timokhin

PSR J0108$-$1431 is an old pulsar where the X-ray emission is expected to have a thermal component from the polar cap and a non-thermal component from the magnetosphere. Although the phase-integrated spectra are fit best with a single…

High Energy Astrophysical Phenomena · Physics 2019-09-04 Prakash Arumugasamy , Dipanjan Mitra

A fully general relativistic description of the pulsar magnetosphere is provided. To be more concrete, a study of the pulsar magnetosphere is performed in the context of general relativistic magnetohydrodynamics (MHD) employing the…

Astrophysics · Physics 2007-05-23 Hongsu Kim , Hyung Mok Lee , Chul H. Lee , Hyun Kyu Lee

Dissipative axisymmetric pulsar magnetosphere is calculated by a direct numerical simulation of the Strong-Field Electrodynamics equations. The magnetic separatrix disappears, it is replaced by a region of enhanced dissipation. With a…

Astrophysics · Physics 2009-06-23 Andrei Gruzinov

Multi-wavelength observations of pulsar emission properties are powerful means to constrain their magnetospheric activity and magnetic topology. Usually a star centred magnetic dipole model is invoked to explain the main characteristics of…

High Energy Astrophysical Phenomena · Physics 2020-01-08 Jérôme Pétri , Dipanjan Mitra

Understanding the physics of rotation-powered millisecond pulsars (MSPs) presents a number of challenges compared to that of the non-recycled pulsar population. Even though their fast rotation rates can produce high spin-down power and…

High Energy Astrophysical Phenomena · Physics 2022-04-06 Alice K. Harding

The magnetic deformation of magnetars is affected by their internal magnetic fields, which are generally difficult to be measured directly through observations. In this work, the periodic pulse-phase modulations in the hard X-ray emissions…

High Energy Astrophysical Phenomena · Physics 2025-01-07 Jie Shu , Quan Cheng , Xiao-Ping Zheng

We show that a pair of thermal, antipodal hot-spots on the neutron star surface is able to fully account for the pulsar's double blackbody spectrum and energy-dependent pulse profile, including the observed 180 degree phase reversal at…

High Energy Astrophysical Phenomena · Physics 2015-05-20 E. V. Gotthelf , R. Perna , J. P. Halpern