Blowing Star Formation Away in AGN Hosts (BAH) -- III. Serendipitous discovery of a $z\sim 2.9$ star-forming galaxy lensed by the galactic bulge of CGCG 012-070 using JWST NIRSpec

Abstract

We report the detection of a gravitationally lensed galaxy by the nearby spiral galaxy CGCG 012-070 ($z=0.048$) using Integral Field Unit (IFU) observations with the Near-Infrared Spectrograph (NIRSpec) instrument on board the James Webb Space Telescope (JWST). The lensed galaxy is identified through the flux distributions of emission lines in the rest-frame optical, consistent with a source located at a redshift of $z\sim 2.89$. The system is detected in [O III]$\lambda \lambda 4959,5007$, H$\beta$, and H$\alpha$ emission lines, exhibiting line ratios typical of a star-forming galaxy. The emission-line flux distributions reveal three distinct components, which are modeled using an elliptical power-law (EPL) mass profile for the lens galaxy. This model provides a good characterization of the source and reveals a disturbed star-forming morphology consistent with those of galaxies at cosmic noon. This serendipitous discovery of a rare low-redshift strong lens highlights the critical role of IFU observations in expanding the lens census and advancing our understanding of galaxy mass profiles and evolution.

Accepted by A&A Letters, 6 pages

References in corpus (16)

• Euclid. I. Overview of the Euclid mission
• UV-extended E-MILES stellar population models: young components in massive early-type galaxies
• The Sloan Lens ACS Survey. V. The Full ACS Strong-Lens Sample
• Full spectrum fitting with photometry in pPXF: stellar population versus dynamical masses, non-parametric star formation history and metallicity for 3200 LEGA-C galaxies at redshift z~0.8
• The Near-Infrared Spectrograph (NIRSpec) on the James Webb Space Telescope III. Integral-field spectroscopy
• The SINFONI Nearby Elliptical Lens Locator Survey: Discovery of two new low-redshift strong lenses and implications for the initial mass function in giant early-type galaxies
• PyAutoLens: Open-Source Strong Gravitational Lensing
• Automated galaxy-galaxy strong lens modelling: no lens left behind
• Substructure Detection Reanalyzed: Dark Perturber shown to be a Line-of-Sight Halo
• Abell 1201: Detection of an Ultramassive Black Hole in a Strong Gravitational Lens
• Systematic errors induced by the elliptical power-law model in galaxy-galaxy strong lens modeling
• A Survey for High-redshift Gravitationally Lensed Quasars and Close Quasars Pairs. I. the Discoveries of an Intermediately-lensed Quasar and a Kpc-scale Quasar Pair at $z\sim 5$
• GLaD: Gravitational Lensing and Dynamics, combined analysis to unveil properties of high-redshift galaxies
• Euclid: A complete Einstein ring in NGC 6505
• AGEL: Is the Conflict Real? Investigating Galaxy Evolution Models using Strong Lensing at 0.3 < z < 0.9
• Systematics in ETG Mass Profile Modelling: Strong Lensing & Stellar Dynamics