Numerical Methods for Gravitational Lensing: A Weak Lensing Analysis Pipeline

by Mr. Ron Peled

BGU

at Astrophysics and Cosmology Seminar

Wed, 17 Jul 2024, 11:10
Sacta-Rashi Building for Physics (54), room 207

Abstract

Gravitational lensing, the phenomenon in which light gets deflected by astrophysical and cosmological structures, is a great tool for investigating the Universe in a wide range of scales: from detecting exoplanets to measuring its effects on the CMB anisotropies. In this work, we aim to construct a pipeline that exploits the weak-lensing (WL) regime for computing a galaxy cluster's mass distribution. In this regime, only one distorted image is created for a given source. By using shape measurement and statistical analysis, we are able to detect the WL signal that the galaxy cluster induces on background sources, and then, by using Kaizer & Squires (1993) inversion technique, we are able to obtain the cluster's mass distribution. As a test case, we are using the Abell-2744 galaxy cluster, as was captured by the JWST's NIRCam instrument. The JWST is a great tool for this kind of work: with the deeper, sharper, and broader wavelength range of imaging that it allows, we are able to detect more background sources, perform better ellipticity measurements, and therefore enhance our WL signal detection abilities. We are able to show convincing results, which then opens the possibility for using this pipeline for future studies of newly-imaged galaxy clusters.

Created on 15-07-2024 by Zitrin, Adi (zitrin)
Updaded on 15-07-2024 by Zitrin, Adi (zitrin)