Hills and holes in the microlensing light curve due to plasma environment around gravitational lens

Abstract

In this paper, we investigate the influence of the plasma surrounding the gravitational lens on the effect of microlensing. In presence of plasma around the lens, the deflection angle is determined by both the gravitational field of the lens and the chromatic refraction in the inhomogeneous plasma. We calculate microlensing light curves numerically for point-mass lens surrounded by power-law density distribution of plasma. A variety of possible curves is revealed, depending on the plasma density and frequency of observations. In the case of significant influence of plasma, the shape of microlensing light curve is strongly deformed in comparison with vacuum case. If the refractive deflection is large enough to compensate or to overcome the gravitational deflection, microlensing images can completely disappear for the observer. In this case, the remarkable effect occurs: formation of a 'hole' instead of a 'hill' in the center of microlensing light curve. Observational prospects of 'hill-hole' effect in different microlensing scenarios are discussed.

Published in MNRAS

References in corpus (15)

• Black Hole Shadows, Photon Rings, and Lensing Rings
• The Shadow of a Spherically Accreting Black Hole
• Frequency-dependent effects of gravitational lensing within plasma
• A comparison of approximate gravitational lens equations and a proposal for an improved new one
• Gravitational Lensing in presence of Plasma: Strong Lens Systems, Black Hole Lensing and Shadow
• Gravitational lensing in a non-uniform plasma
• 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
• Gravitational radiospectrometer
• Influence of a plasma on the observational signature of a high-spin Kerr black hole
• Escape and Trapping of Low-Frequency Gravitationally Lensed Rays by Compact Objects within Plasma
• Gravitational Lensing of Rays through the Levitating Atmospheres of Compact Objects
• Spatial dispersion of light rays propagating through a plasma in Kerr spacetime
• Radio Monitoring Campaigns of Six Strongly Lensed Quasars
• Dual-Component Plasma Lens Models

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• Shadows of rotating black holes in plasma environments with aberration effects
• Analytical expressions for pulse profile of neutron stars in plasma environments
• Time delay induced by plasma in strong lens systems
• Binary microlensing with plasma environment -- Star and planet
• The Multiple Images of the Plasma Lensing FRB
• Perturbative and numerical approach to plasma strong lensing
• Effects of the refractive index of the X-ray corona on the emission lines in AGN
• Deflection of light rays in a moving medium around a spherically symmetric gravitating object
• Ray Tracing Through Absorbing Dielectric Media in the Schwarzschild Spacetime
• Plasma lens with frequency-dependent dispersion measure effects on fast radio bursts
• Deciphering signatures of Kerr-Sen black holes in presence of plasma from the Event Horizon Telescope data
• Light deflection in axially symmetric stationary spacetimes filled with a moving medium
• Investigating the interplay of the braneworld gravity and the plasma environment on the black hole shadow