Faraday Rotation in Pulsar Magnetosphere

Abstract

The magnetosphere of a pulsar is composed of relativistic plasmas streaming along the magnetic field lines and corotating with the pulsar. We study the intrinsic Faraday rotation in the pulsar magnetosphere by critically examining the wave modes and the variations of polarization properties for the circularly polarized natural modes under various assumptions about the magnetosphere plasma properties. Since it is difficult to describe analytically the Faraday rotation effect in such a plasma, we use numerical integrations to study the wave propagation effects in the corotating magnetosphere. Faraday rotation effect is identified among other propagation effects, such as wave mode coupling and the cyclotron absorption. In a highly symmetrical electron-positron pair plasma, the Faraday rotation effect is found to be negligible. Only for asymmetrical plasmas, such as the electron-ion streaming plasma, can the Faraday rotation effect become significant, and the Faraday rotation angle is found to be approximately proportional to ${\lambda }^{0.5}$ instead of the usual ${\lambda }^2$-law. For such electrons-ion plasma of pulsar magnetosphere, the induced rotation measure becomes larger at higher frequencies, and should have opposite signs for the emissions from opposite magnetic poles.

15 pages, 4 figure, submitted to MNRAS

References in corpus (6)

• Atmosphere Models of Magnetized Neutron Stars: QED Effects, Radiation Spectra, and Polarization Signals
• The population of pulsars with interpulses and the implications for beam evolution
• The complex polarization angles of radio pulsars: orthogonal jumps and interstellar scattering
• Wave Modes in the Magnetospheres of Pulsars and Magnetars
• Faraday rotation: effect of magnetic field reversals
• On the radio wave propagation in the pulsar magnetosphere

Cited by in corpus (20)

• Calibrating High-Precision Faraday Rotation Measurements for LOFAR and the Next Generation of Low-Frequency Radio Telescopes
• A Study of Multi-frequency Polarization Pulse Profiles of Millisecond Pulsars
• Low-frequency Faraday rotation measures towards pulsars using LOFAR: probing the 3-D Galactic halo magnetic field
• On the mean profiles of radio pulsars I: Theory of the propagation effects
• Radio pulsars: already fifty years!
• On the Apparent Nulls and Extreme Variability of PSR J1107-5907
• Do pulsars rotate clockwise or counterclockwise?
• The POlarised GLEAM Survey (POGS) II: Results from an All-Sky Rotation Measure Synthesis Survey at Long Wavelengths
• Testing the accuracy of the ionospheric Faraday rotation corrections through LOFAR observations of bright northern pulsars
• Interacting Large-Scale Magnetic Fields and Ionised Gas in the W50/SS433 System
• Propagation of a fast radio burst through a birefringent relativistic plasma
• Rotation measure variations in Galactic Centre pulsars
• Peering into the Milky Way by FAST: III. Magnetic fields in the Galactic halo and farther spiral arms revealed by the Faraday effect of faint pulsars
• The Chinese pulsar timing array data release I. Polarimetry for 56 millisecond pulsars
• The Curious Case of Twin Fast Radio Bursts: Evidence for Neutron Star Origin?
• Reciprocating Magnetic Fields in the Pulsar Wind Observed from the Black Widow Pulsar J1720-0534
• Axion sourcing in dense stellar matter via CP-violating couplings
• Pulsars as excellent probes for the magnetic structure in our Milky Way
• Exploring Faraday rotation signatures and population bounds for primordial magnetic black holes
• 50-250 MHz Pulsar Census with an SKA-Low prototype station: Spectra and Polarization