Multipole Gravitational Lensing and High-order Perturbations on the Quadrupole Lens

Abstract

An arbitrary surface mass density of gravitational lens can be decomposed into multipole components. We simulate the ray-tracing for the multipolar mass distribution of generalized SIS (Singular Isothermal Sphere) model, based on the deflection angles which are analytically calculated. The magnification patterns in the source plane are then derived from inverse shooting technique. As have been found, the caustics of odd mode lenses are composed of two overlapping layers for some lens models. When a point source traverses such kind of overlapping caustics, the image numbers change by \pm 4, rather than \pm 2. There are two kinds of images for the caustics. One is the critical curve and the other is the transition locus. It is found that the image number of the fold is exactly the average value of image numbers on two sides of the fold, while the image number of the cusp is equal to the smaller one. We also focus on the magnification patterns of the quadrupole (m = 2) lenses under the perturbations of m = 3, 4 and 5 mode components, and found that one, two, and three butterfly or swallowtail singularities can be produced respectively. With the increasing intensity of the high-order perturbations, the singularities grow up to bring sixfold image regions. If these perturbations are large enough to let two or three of the butterflies or swallowtails contact, eightfold or tenfold image regions can be produced as well. The possible astronomical applications are discussed.

24 pages, 6 figures

References in corpus (32)

• Triaxial Modeling of Halo Density Profiles with High-resolution N-body Simulations
• Direct Detection of CDM Substructure
• Strong Lensing by Galaxies
• Gravitational Lensing
• Tests for Substructure in Gravitational Lenses
• Self-Similar Models for the Mass Profiles of Early-type Lens Galaxies
• On the Formation of Boxy and Disky Elliptical Galaxies
• Effects of Dark Matter Substructures on Gravitational Lensing: Results from the Aquarius Simulations
• Constraints on the Inner Mass Profiles of Lensing Galaxies from Missing Odd Images
• The central image of a gravitationally lensed quasar
• Lopsided Spiral Galaxies
• Fitting Gravitational Lenses: Truth or Delusion
• Triaxial Haloes and Particle Dark Matter Detection
• Arc sensitivity to cluster ellipticity, asymmetries and substructures
• A multipole-Taylor expansion for the potential of gravitational lens MG J0414+0534
• Simulations of Strong Gravitational Lensing with Substructure
• CLASS B1152+199 and B1359+154: Two New Gravitational Lens Systems Discovered in the Cosmic Lens All-Sky Survey
• Is the Number of Giant Arcs in LCDM Consistent With Observations?
• B1359+154: A Six Image Lens Produced by a z=1 Compact Group of Galaxies
• Effects of Ellipticity and Shear on Gravitational Lens Statistics
• Halo Structures of Gravitational Lens Galaxies
• An Atlas of Predicted Exotic Gravitational Lenses
• Gravitational Lenses With More Than Four Images: I. Classification of Caustics
• Observation of small scale structure using sextupole lensing
• On the Magnfication Relations in Quadruple Lenses: A Moment Approach
• Are there sextuplet and octuplet image systems?
• Analytic expressions for mean magnification by a quadrupole gravitational lens
• The anatomy of a quadruply imaged gravitational lens system
• A Universal Magnification Theorem for Higher-Order Caustic Singularities
• Smoothing Algorithms and High-order Singularities in Gravitational Lensing
• The Gravitational Lens B1608+656: I. V, I, and H-band HST Imaging
• Multipole Formulae for Gravitational Lensing Shear and Flexion

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