A closer look at the quadruply lensed quasar PSOJ0147: spectroscopic redshifts and microlensing effect

TL;DR

This paper provides spectroscopic measurements of a newly discovered quadruply lensed quasar, determining key redshifts and analyzing microlensing effects, which are essential for future cosmological studies and understanding AGN structure.

Contribution

It offers precise redshift measurements for the lens and source, and demonstrates microlensing effects through difference spectra analysis, advancing gravitational lensing research.

Findings

Redshifts of lens (z=0.572) and quasar (z=2.341) determined.

Microlensing effects observed in difference spectra.

Foundation laid for future cosmography with this system.

Abstract

I present timely spectroscopic follow-up of the newly discovered, quadruply lensed quasar PSOJ0147 from the Pan-STARRS 1 survey. The newly acquired optical spectra with GMOS onboard the Gemini north telescope allow us to pin down the redshifts of both the foreground lensing galaxy and the background lensed quasar to be z=0.572 and 2.341, providing firm basis for cosmography with future high cadence photometric monitoring. I also inspect difference spectra from two of the quasar images, revealing the microlensing effect. Long-term spectroscopic follow-ups will shed lights on the structure of the AGN and its environment.