Extended lens reconstructions with GRALE: Exploiting time-domain, substructural, and weak lensing information

Jori Liesenborgs, Liliya L.R. Williams, Jenny Wagner, Sven de Rijcke

Research output: Contribution to journalArticlepeer-review

Abstract

The information about the mass density of galaxy clusters provided by the gravitational lens effect has inspired many inversion techniques. In this article, updates to the previously introduced method in GRALE are described, and explored in a number of examples. The first looks into a different way of incorporating time delay information, not requiring the unknown source position. It is found that this avoids a possible bias that leads to 'overfocusing' the images, i.e. providing source position estimates that lie in a considerably smaller region than the true positions. The second is inspired by previous reconstructions of the cluster of galaxies MACS J1149.6+2223, where a multiply imaged background galaxy contained a supernova, SN Refsdal, of which four additional images were produced by the presence of a smaller cluster galaxy. The inversion for the cluster as a whole was not able to recover sufficient detail interior to this quad. We show how constraints on such different scales, from the entire cluster to a single member galaxy, can now be used, allowing such small-scale substructures to be resolved. Finally, the addition of weak lensing information to this method is investigated. While this clearly helps recover the environment around the strong lensing region, the mass sheet degeneracy may make a full strong and weak inversion difficult, depending on the quality of the ellipticity information at hand. We encounter ring-like structure at the boundary of the two regimes, argued to be the result of combining strong and weak lensing constraints, possibly affected by degeneracies.

Original languageEnglish (US)
Pages (from-to)3253-3274
Number of pages22
JournalMonthly Notices of the Royal Astronomical Society
Volume494
Issue number3
DOIs
StatePublished - 2020

Bibliographical note

Funding Information:
We gratefully acknowledge the LENSTOOL team for making their models publicly available online. JL acknowledges the use of the computational resources and services provided by the VSC (Flemish Supercomputer Centre), funded by the Research Foundation - Flanders (FWO) and the Flemish Government - department EWI. JW gratefully acknowledges the support by the Deutsche Forschungsgemeinschaft (DFG) WA3547/1-3. SDR acknowledges financial support from the European Union's Horizon 2020 research and innovation programme under the Marie Sk?odowska-Curie grant agreement No 721463 to the SUNDIAL ITN network.

Funding Information:
We gratefully acknowledge the LENSTOOL team for making their models publicly available online. JL acknowledges the use of the computational resources and services provided by the VSC (Flemish Supercomputer Centre), funded by the Research Foundation – Flanders (FWO) and the Flemish Government – department EWI. JW gratefully acknowledges the support by the Deutsche Forschungsgemeinschaft (DFG) WA3547/1-3. SDR acknowledges financial support from the European Union’s Horizon 2020 research and innovation programme under the Marie Skłodowska-Curie grant agreement No 721463 to the SUNDIAL ITN network.

Publisher Copyright:
© 2020 The Author(s)

Keywords

  • Dark matter
  • Galaxies: clusters: general
  • Gravitational lensing: strong
  • Gravitational lensing: weak
  • Methods: data analysis

Fingerprint

Dive into the research topics of 'Extended lens reconstructions with GRALE: Exploiting time-domain, substructural, and weak lensing information'. Together they form a unique fingerprint.

Cite this