Open AccessCaustic Crossing Events and Source Models in Gravitational Lens Systems
Author(s) -
A. N. Alexandrov,
В. І. Жданов,
V. M. Sliusar
Publication year - 2022
Publication title -
ukrainian journal of physics
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.213
H-Index - 17
eISSN - 2071-0194
pISSN - 2071-0186
DOI - 10.15407/ujpe56.4.389
Subject(s) - quasar , caustic (mathematics) , physics , magnification , gravitational lens , brightness , lens (geology) , galaxy , astrophysics , gravitational microlensing , strong gravitational lensing , gravitation , gaussian , astronomy , optics , quantum mechanics , mathematical physics , redshift
High amplification events (HAEs) are common phenomena in extragalactic gravitational lens systems (GLSs), where the multiple images of a distant quasar are observed through a foreground galaxy. There is a considerable brightness magnification in one of the quasar images during HAE. Grieger, Kayser, and Refsdal (1988) proposed to use HAEs to study the central regions of quasars inGLSs. In this paper, we consider some problems concerning the identification of different source types on the basis of the HAE observations. We compare the results of light curve simulations to estimate a feasibility to distinguish different source models in GLSs. Analytic approximation methods yielding solutions of the lens equation in a vicinity of fold caustic crossing events are presented. The results are used to obtain amplification factors, which the higher-order corrections for the Gaussian, power-law, andlimb-darkening models of a source take into account.