COOL-LAMPS. V. Discovery of COOL J0335$-$1927, a Gravitationally Lensed Quasar at $z$=3.27 with an Image Separation of 23.3"

Author:

Kate Napier, Mike Gladders, Keren Sharon, Håkon Dahle, Aidan P. Cloonan, Guillaume Mahler, Isaiah Escapa, Josh Garza, Andrew Kisare, Natalie Malagon, Simon Mork, Kunwanhui Niu, Riley Rosener, Jamar Sullivan Jr., Marie Tagliavia, Marcos Tamargo, Raul Teixeira, Kabelo Tsiane, Grace Wagner, Yunchong Zhang, Megan Zhao

Keyword:

Astrophysics, Astrophysics of Galaxies, Astrophysics of Galaxies (astro-ph.GA), Cosmology and Nongalactic Astrophysics (astro-ph.CO)

journal:

date:

2023-05-22 16:00:00

Abstract

We report the discovery of COOL J0335$-$1927, a quasar at z = 3.27 lensed into three images with a maximum separation of 23.3" by a galaxy cluster at z = 0.4178. To date this is the highest redshift wide-separation lensed quasar known. In addition, COOL J0335$-$1927 shows several strong intervening absorbers visible in the spectra of all three quasar images with varying equivalent width. The quasar also shows mini-broad line absorption. We construct a parametric strong gravitational lens model using ground-based imaging, constrained by the redshift and positions of the quasar images as well as the positions of three other multiply-imaged background galaxies. Using our best-fit lens model, we calculate the predicted time delays between the three quasar images to be $\Delta$t$_{AB}=$ $499^{+141}_{-146}$ (stat) and $\Delta$t$_{AC}=$ $-127^{+83}_{-17}$ (stat) days. Folding in systematic uncertainties, the model-predicted time delays are within the ranges $240 < \Delta$t$_{AB} < 700$ and $-300 < \Delta$ t$_{AC} <-30$. We also present g-band photometry from archival DECaLS and Pan-STARRS imaging, and new multi-epoch observations obtained between September 18, 2022 UT and February 22, 2023 UT, which demonstrate significant variability in the quasar and which will eventually enable a measurement of the time delay between the three quasar images. The currently available light curves are consistent with the model-predicted time delays. This is the fifth paper from the COOL-LAMPS collaboration.

PDF: COOL-LAMPS. V. Discovery of COOL J0335$-$1927, a Gravitationally Lensed Quasar at $z$=3.27 with an Image Separation of 23.3".pdf