Frequency-dependent effects of gravitational lensing within plasma

Abstract

The interaction between refraction from a distribution of inhomogeneous plasma and gravitational lensing introduces novel effects to the paths of light rays passing by a massive object. The plasma contributes additional terms to the equations of motion, and the resulting ray trajectories are frequency-dependent. Lensing phenomena and circular orbits are investigated for plasma density distributions $N\propto 1/r^h$ with $h\ge 0$ in the Schwarzschild space-time. For rays passing by the mass near the plasma frequency refractive effects can dominate, effectively turning the gravitational lens into a mirror. We obtain the turning points, circular orbit radii, and angular momentum for general $h$. Previous results have shown that light rays behave like massive particles with an effective mass given by the plasma frequency for a constant density $h=0$. We study the behaviour for general $h$ and show that when $h=2$ the plasma term acts like an additional contribution to the angular momentum of the passing ray. When $h=3$ the potential and radii of circular orbits are analogous to those found in studies of massless scalar fields on the Schwarzschild background. As a physically motivated example we study the pulse profiles of a compact object with antipodal hotspots sheathed in a dense plasma, which shows dramatic frequency-dependent shifts from the behaviour in vacuum. Finally, we consider the potential observability and applications of such frequency-dependent plasma effects in general relativity for several types of neutron star.

10 pages, 6 figures

References in corpus (11)

• 1E 1547.0-5408: a radio-emitting magnetar with a rotation period of 2 seconds
• Asymmetries in core-collapse supernovae from maps of radioactive ${}^{44}$Ti in CassiopeiaA
• Gravitational radiospectrometer
• Instantaneous Radio Spectra of Giant Pulses from the Crab Pulsar from Decimeter to Decameter Wavelengths
• Frequency dependence of pulse width for 150 radio normal pulsars
• Light defection due to a charged, rotating body
• Polarized Curvature Radiation in Pulsar Magnetosphere
• Semi-analytic results for quasi-normal frequencies
• Gravitational red-shift and deflection of slow light
• Hints of a second explosion (a quark nova) in Cassiopeia A Supernova
• Bending of a light ray within a dispersive medium in a uniform gravitational field

Cited by in corpus (55)

• Gravitational Lensing in presence of Plasma: Strong Lens Systems, Black Hole Lensing and Shadow
• Shadows and gravitational weak lensing by the Schwarzschild black hole in the string cloud background with quintessential field
• Axion-plasmon or magnetized plasma effect on an observable shadow and gravitational lensing of a Schwarzschild black hole
• Two families of astrophysical diverging lens models
• Higher order corrections to deflection angle of massive particles and light rays in plasma media for stationary spacetimes using the Gauss-Bonnet theorem
• Black Hole Shadow in Symmergent Gravity
• Shadow of a Charged Rotating Non-Commutative Black Hole
• Shadow and weak gravitational lensing of a rotating regular black hole in a non-minimally coupled Einstein-Yang-Mills theory in the presence of plasma
• Influence of a plasma on the observational signature of a high-spin Kerr black hole
• Weak gravitational lensing and shadow of a GUP-modified Schwarzschild black hole in the presence of plasma
• Motion of Particles and Gravitational Lensing Around (2+1)-dimensional BTZ black holes in Gauss-Bonnet Gravity
• Escape and Trapping of Low-Frequency Gravitationally Lensed Rays by Compact Objects within Plasma
• Quantum effects on the black hole shadow and deflection angle in presence of plasma
• Gravitational Lensing of Rays through the Levitating Atmospheres of Compact Objects
• Study of circular geodesics and shadow of rotating charged black hole surrounded by perfect fluid dark matter immersed in plasma
• Noncommutative Schwarzschild black hole surrounded by quintessence: Thermodynamics, Shadows and Quasinormal modes
• Shadows of Kerr black holes with a Gaussian-distributed plasma in the polar direction
• Hills and holes in the microlensing light curve due to plasma environment around gravitational lens
• Strong deflection limit analysis of black hole lensing in inhomogeneous plasma
• Probing Geometric Proca in Metric-Palatini Gravity with Black Hole Shadow and Photon Motion
• Shadow of black hole surrounded by magnetized plasma: Axion-plasmon cloud
• Shadows of rotating black holes in plasma environments with aberration effects
• Effect of magnetized plasma on shadow and gravitational lensing of a Reissner-Nordström black hole
• Deflection angle evolution with plasma medium and without plasma medium in a parameterized black hole
• Weak Deflection angle and Shadow by Tidal Charged Black Hole
• Shadow of the $5D$ Reissner-Nordström AdS Black Hole
• Deflection Light Behaviors by AdS Black Holes
• Light deflection by squashed Kaluza-Klein black holes in a plasma medium
• Shadow and weak deflection angle of a black hole in nonlocal gravity
• Geodesics and scalar perturbations of Schwarzschild black holes embedded in a Dehnen-type dark matter halo with quintessence
• Probing a polymerized black hole with the frequency shifts of photons
• Time delay induced by plasma in strong lens systems
• Analytical expressions for pulse profile of neutron stars in plasma environments
• Dual-Component Plasma Lens Models
• Shadow of Kottler black hole in the presence of plasma for a co-moving observer
• Binary microlensing with plasma environment -- Star and planet
• Black Hole Shadows in Einstein-Bel-Robinson Gravity
• Weak Gravitational Lensing in Ricci-Coupled Kalb-Ramond Bumblebee Gravity: Global Monopole and Axion-Plasmon Medium Effects
• Perturbative and numerical approach to plasma strong lensing
• Testing new massive conformal gravity with the light deflection by black hole
• Deflection of light rays in a moving medium around a spherically symmetric gravitating object
• Lensing Stability and Scattering Phenomena in Anisotropic Black Hole Spacetimes in Plasma
• Ray Tracing Through Absorbing Dielectric Media in the Schwarzschild Spacetime
• Thermal and Optical Signatures of Einstein-Dyonic ModMax Black Holes with GUP and Plasma Modifications
• Observational signatures of Rotating compact objects in Plasma space-time
• Shadows of a Non-Commutative Black Hole under the Influence of a Magnetized Plasma
• Deciphering signatures of Kerr-Sen black holes in presence of plasma from the Event Horizon Telescope data
• Revisiting Einstein's analogy: black holes as gradient-index lenses
• Redshift Spectroscopy as a Probe of Regular Black Holes, Black Bounces, and Scalar-Hair Compact Objects
• Investigating the interplay of the braneworld gravity and the plasma environment on the black hole shadow
• Light deflection in axially symmetric stationary spacetimes filled with a moving medium
• Spin Hall effects and the localization of massless spinning particles
• Chandra X-ray Observations of the Neutron Star Merger GW170817: Thermal X-Ray Emission From a Kilonova Remnant?
• Decoding Horizonless Spacetime: Plasma-Induced Features in a Rotating Wormhole Shadow
• Axion-Photon Conversion Signals from Neutron Stars with Spacetime Curvature Accounted for in the Magnetosphere Model