KerrSen dilatonaxion black hole lensing in the strong deflection limit
Abstract
In the present work we study numerically quasiequatorial lensing by the charged, stationary, axially symmetric KerrSen dilatonaxion black hole in the strong deflection limit. In this approximation we compute the magnification and the positions of the relativistic images. The most outstanding effect is that the KerrSen black hole caustics drift away from the optical axis and shift in the clockwise direction with respect to the Kerr caustics. The intersections of the critical curves on the equatorial plane as a function of the black hole angular momentum are found, and it is shown that they decrease with the increase of the parameter Q{sup 2}/M. All of the lensing quantities are compared to particular cases as Schwarzschild, Kerr, and GibbonsMaeda black holes.
 Authors:
 Department of Theoretical Physics, Faculty of Physics, Sofia University, 5 James Bourchier Boulevard, 1164 Sofia (Bulgaria)
 Publication Date:
 OSTI Identifier:
 20935201
 Resource Type:
 Journal Article
 Resource Relation:
 Journal Name: Physical Review. D, Particles Fields; Journal Volume: 75; Journal Issue: 2; Other Information: DOI: 10.1103/PhysRevD.75.023006; (c) 2007 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA)
 Country of Publication:
 United States
 Language:
 English
 Subject:
 72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS; ANGULAR MOMENTUM; APPROXIMATIONS; AXIAL SYMMETRY; AXIONS; BLACK HOLES; KERR FIELD; RELATIVISTIC RANGE
Citation Formats
Gyulchev, Galin N., and Yazadjiev, Stoytcho S. KerrSen dilatonaxion black hole lensing in the strong deflection limit. United States: N. p., 2007.
Web. doi:10.1103/PHYSREVD.75.023006.
Gyulchev, Galin N., & Yazadjiev, Stoytcho S. KerrSen dilatonaxion black hole lensing in the strong deflection limit. United States. doi:10.1103/PHYSREVD.75.023006.
Gyulchev, Galin N., and Yazadjiev, Stoytcho S. Mon .
"KerrSen dilatonaxion black hole lensing in the strong deflection limit". United States.
doi:10.1103/PHYSREVD.75.023006.
@article{osti_20935201,
title = {KerrSen dilatonaxion black hole lensing in the strong deflection limit},
author = {Gyulchev, Galin N. and Yazadjiev, Stoytcho S.},
abstractNote = {In the present work we study numerically quasiequatorial lensing by the charged, stationary, axially symmetric KerrSen dilatonaxion black hole in the strong deflection limit. In this approximation we compute the magnification and the positions of the relativistic images. The most outstanding effect is that the KerrSen black hole caustics drift away from the optical axis and shift in the clockwise direction with respect to the Kerr caustics. The intersections of the critical curves on the equatorial plane as a function of the black hole angular momentum are found, and it is shown that they decrease with the increase of the parameter Q{sup 2}/M. All of the lensing quantities are compared to particular cases as Schwarzschild, Kerr, and GibbonsMaeda black holes.},
doi = {10.1103/PHYSREVD.75.023006},
journal = {Physical Review. D, Particles Fields},
number = 2,
volume = 75,
place = {United States},
year = {Mon Jan 15 00:00:00 EST 2007},
month = {Mon Jan 15 00:00:00 EST 2007}
}

We investigate analytical gravitational lensing by charged, stationary, axially symmetric KerrSen dilatonaxion black holes in the weakdeflection limit. Approximate solutions to the lightlike equations of motion are present up to and including thirdorder terms in M/b, a/b, and r{sub {alpha}/}b, where M is the black hole mass, a is the angular momentum, r{sub {alpha}=}Q{sup 2}/M, Q being the charge and b is the impact parameter of the light ray. We compute the positions of the two weak field images, the corresponding signed and absolute magnifications up to postNewtonian order. It is shown that there are static postNewtonian corrections to themore »

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