Polarized x-rays from a magnetar

Abstract

We report on the first detection of linearly polarized x-ray emission from an ultra-magnetized neutron star with the Imaging X-ray Polarimetry Explorer (IXPE). The IXPE 35 observations of the anomalous x-ray pulsar 4U 0142+61 reveal a linear polarization degree of $(12\pm 1)\%$ throughout the IXPE 2--8 keV band. We detect a substantial variation of the polarization with energy: the degree is $(14\pm 1)\%$ at 2--4 keV and $(41\pm 7)\%$ at 5.5--8 keV, while it drops below the instrumental sensitivity around 4--5 keV, where the polarization angle swings by $\sim 90^{\circ }$. The IXPE observations give us completely new information about the properties of the neutron star surface and magnetosphere and lend further support to the presence of the quantum mechanical effect of vacuum birefringence.

32 pages, 9 figures, 3 tables

References in corpus (15)

• Physics of Strongly Magnetized Neutron Stars
• Analyzing the Data from X-ray Polarimeters with Stokes Parameters
• ixpeobssim: a Simulation and Analysis Framework for the Imaging X-ray Polarimetry Explorer
• PINT: A Modern Software Package for Pulsar Timing
• Design, Construction, and Test of the Gas Pixel Detectors for the IXPE Mission
• A weighted analysis to improve the X-ray polarization sensitivity of IXPE
• Detailed high-energy characteristics of AXP 4U 0142+61 - Multi-year observations with INTEGRAL, RXTE, XMM-Newton and ASCA
• Relativistic rotating vector model for X-ray millisecond pulsars
• Very deep X-ray observations of the Anomalous X-ray Pulsar 4U 0142+614
• X-ray spectra and polarization from magnetar candidates
• Unbinned Likelihood Analysis for X-ray Polarization
• Extending the $Z_n^2$ and $H$ statistics to generic pulsed profiles
• Towards Optimal Signal Extraction for Imaging X-ray Polarimetry
• Opacities and spectra of hydrogen atmospheres of moderately magnetized neutron stars
• Analysis of the data from photoelectric gas polarimeters

Cited by in corpus (24)

• Handling Background in IXPE polarimetric data
• X-ray polarimetry and spectroscopy of the neutron star low-mass X-ray binary GX 9+9: an in-depth study with IXPE and NuSTAR
• A strong X-ray polarization signal from the magnetar 1RXS J170849.0-400910
• IXPE Detection of Polarized X-rays from Magnetars and Photon Mode Conversion at QED Vacuum Resonance
• X-ray pulsar GRO J1008$-$57 as an orthogonal rotator
• Report on Progress in Physics: Observation of the Breit-Wheeler Process and Vacuum Birefringence in Heavy-Ion Collisions
• Exploring Nonlinear Electrodynamics Theories: Shadows of Regular Black Holes and Horizonless Ultra-Compact Objects
• Precession of magnetars: dynamical evolutions and modulations on polarized electromagnetic waves
• Premerger phenomena in neutron-star binary coalescences
• Polarization Signals from Axion-Photon Resonant Conversion in Neutron Star Magnetosphere
• X-ray Polarisation in Magnetar Atmospheres -- Effects of Mode Conversion
• Magnetar structure in non-linear electrodynamics with mixed poloidal-toroidal fields
• X-ray polarisation signatures in bombarded magnetar atmospheres
• Vacuum birefringence and the polarized X-ray emission from a radio magnetar
• Monte Carlo Simulations of Polarized Radiative Transfer in Neutron Star Atmospheres
• Photon polarization tensor at finite temperature and density in a magnetic field
• Pulsed, Polarized X-ray Emission from Neutron Star Surfaces: the Effects of Vacuum Birefringence in the Magnetosphere
• Pulsed and Polarized X-ray Emission from Neutron Star Surfaces
• 3+1 formulation of light modes in nonlinear electrodynamics
• Instruments for Focal Plane X-Ray Polarimetry in the Next Decade
• Energy Loss of Newborn Magnetars by Schwinger Process
• Quantum refraction effects in pulsar radio emission
• Resonant Inverse Compton Scattering and Hard X-ray Emission in Magnetar Magnetospheres
• Nonlinear electrodynamics in magnetars: systematic effects on radius constraints and timing analysis