Fast simulations of extragalactic microlensing

TL;DR

This paper introduces a rapid and resource-efficient method for generating microlensing magnification maps, enabling large-scale extragalactic microlensing studies with minimal computational resources.

Contribution

A novel combination of a 2D Poisson solver and inverse polygon mapping significantly accelerates magnification map generation at high optical depths.

Findings

Magnification maps of 2000x2000 pixels can be generated in seconds.

The method reduces computational resource requirements.

It enables online access and large-scale production of microlensing maps.

Abstract

We present a new and very fast method for producing microlensing magnification maps at high optical depths. It is based on the combination of two approaches: (a) the two-dimensional Poisson solver for a deflection potential and (b) inverse polygon mapping. With our method we extremely reduce the computing time for the generation of magnification patterns and avoid the use of highly demanding computer resources. For example, the generation of a magnification map of size 2000 x 2000 pixels, covering a region of 20 Einstein radii, takes a few seconds on a state-of-the-art laptop. The method presented here will facilitate the massive production of magnification maps for extragalactic microlensing studies within the forthcoming surveys without the need for large computer clusters. The modest demand of computer power and a fast execution time allow the code developed here to be placed on a standard server and thus provide the public online access through a web-based interface.