Survey of Gravitationally-lensed Objects in HSC Imaging (SuGOHI). VIII. New galaxy-scale lenses from the HSC SSP

TL;DR

This paper reports a systematic search for galaxy-scale strong gravitational lenses in the HSC SSP data, identifying new lens candidates and classifying their likelihood, with implications for studying galaxy evolution.

Contribution

It introduces an automated method combining YattaLens and visual inspection to identify new galaxy-scale lenses in the HSC SSP data, expanding the lens sample at intermediate redshifts.

Findings

8 definite lenses identified

28 probable lenses identified

138 possible lenses identified

Abstract

We conduct a search for galaxy-scale strong gravitational lens systems in Data Release 4 of the Hyper Suprime-Cam Subaru Strategic Program (HSC SSP), consisting of data taken up to the S21A semester. We select 103191 luminous red galaxies from the Baryon Oscillation Spectroscopic Survey (BOSS) sample that have deep multiband imaging from the HSC SSP and use the YattaLens algorithm to automatically identify lens candidates with blue arc-like features. The candidates are visually inspected and graded based on their likelihood of being a lens. We find 8 definite lenses, 28 probable lenses, and 138 possible lenses. The new lens candidates generally have lens redshifts in the range $0.3 \lesssim z_{\mathrm{L}} \lesssim 0.9$, a key intermediate redshift range to study the evolution of galaxy structure. Follow-up spectroscopy will confirm these new lenses and measure source redshifts to enable detailed lens modeling.