An edge-on disk in the quadruply lensed quasar cross GraL~J181730853+272940139

TL;DR

This paper presents the first mass model of the quadruply lensed quasar GraL J181730853+272940139, utilizing new Subaru imaging to analyze the lensing galaxy's properties and improve understanding of this unusual system.

Contribution

It provides the first detailed mass model of the system using high-resolution Subaru imaging, advancing knowledge of this recently discovered quadruply lensed quasar.

Findings

Mass model of the lensing galaxy derived from Subaru data

Measured relative astrometry and morphology of the lensing galaxy

Enhanced understanding of the system's lensing configuration

Abstract

Data mining through large, multi-band ground-based surveys and the recent availability of source catalogues from the {\it Gaia} space mission has led to a surge in the number of known gravitationally lensed quasars, including some unusual systems. One of these newly discovered systems is GraL~J181730853+272940139. This system was reported in Delchambre et al. 2018, and was identified as a quadruply lensed quasar candidate via a machine learning search inside {\it Gaia} Data Release 2, where it consists of three sources with maximum separation $1.8''$. Lemon et al. in prep (private communications) confirmed it spectroscopically as a lensed quasar with source redshift $z=3.07$. A mass model of this system has not been published to date, and the highest resolution imaging data available is from PanSTARRS1 \citep{chambers16}, with seeing $\sim1.0''-1.3''$ in the $grizy$ filters. Here we present the first mass model of J1817+2729, which includes the measured relative astrometry and morphology of the lensing galaxy, using newly acquired Subaru/FOCAS imaging.