Nonlinear optics in strongly magnetized pair plasma, with applications to FRBs

Abstract

Intense radiation field can modify plasma properties, the corresponding refractive index, and lead to such nonlinear propagation effects as self-focusing. We estimate the corresponding effects in pair plasma, both in unmagnetized and strongly magnetically dominated case. First, in the unmagnetized pair plasma the ponderomotive force does not lead to charge separation, but to density depletion. Second, for astrophysically relevant plasmas of pulsar magnetospheres, (and possible loci of Fast Radio Bursts), where cyclotron frequency ${\omega }_B$ dominates over plasma frequency ${\omega }_p$ and the frequency of the electromagnetic wave, ${\omega }_B\gg {\omega }_p,\omega$, we show that (i) there is virtually no nonlinearity due to changing effective mass in the field of the wave; (ii) ponderomotive force is $F_p^{(B)}=-m_e{c}^2/(4B_0^2)\nabla E^2$; it is reduced by a factor $(\omega /{\omega }_B{)}^2$ if compared to the unmagnetized case ($B_0$ is the external magnetic field and $E$ is the electric field of the wave); (iii) for radiation beam propagating along constant magnetic field in pair plasma with density $n_{\pm }$, the ponderomotive force leads to appearance of circular currents that lead to the decrease of the field within the beam by a factor $\Delta B/B_0=2\pi n_{\pm }{m}_e{c}^2{E}^2/B_0^4$. Applications to the physics of FRBs are discussed; we conclude that for parameters of FRB's the dominant magnetic field completely suppresses nonlinear radiation effects.

References in corpus (22)

• A bright millisecond radio burst of extragalactic origin
• Nonlinear collective effects in photon-photon and photon-plasma interactions
• Magnetars
• Electrodynamics of Magnetars: Implications for the Persistent X-ray Emission and Spindown of the Soft Gamma Repeaters and Anomalous X-ray Pulsars
• Fast Radio Bursts
• Fast Radio Bursts: An Extragalactic Enigma
• A Living Theory Catalogue for Fast Radio Bursts
• CHIME/FRB Detection of Eight New Repeating Fast Radio Burst Sources
• FRB 121102 Bursts Show Complex Time-Frequency Structure
• Supergiant Pulses from Extragalactic Neutron Stars
• A Second Source of Repeating Fast Radio Bursts
• Fast radio bursts as giant pulses from young rapidly rotating pulsars
• CHIME/FRB Detection of the Original Repeating Fast Radio Burst Source FRB 121102
• Fast Radio Bursts' emission mechanism: implication from localization
• Cherenkov-Curvature Radiation and Pulsar Radio Emission Generation
• Radius-to-frequency mapping and FRB frequency drifts
• Giant Pulses -- the Main Component of the Radio Emission of the Crab Pulsar
• Beam Instabilities in Magnetized Pair Plasma
• Coherence constraints on physical parameters at bright radio sources and FRB emission mechanism
• Nonlinear scattering of Fast Radio Bursts
• Stimulated-emission based model of fast radio bursts
• Self-trapping as the possible beaming mechanism for FRB

Cited by in corpus (7)

• The Physics of Fast Radio Bursts
• Coherent emission in pulsars, magnetars and Fast Radio Bursts: reconnection-driven free electron laser
• Can a strong radio burst escape the magnetosphere of a magnetar?
• Fast Radio Bursts from reconnection events in magnetar magnetospheres
• Self-modulation of Fast Radio Bursts
• Down-drifting, bandwidth and beaming of fast radio bursts
• Emission Mechanisms of Fast Radio Bursts