A New Quadruply Lensed Quasar: SDSSJ125107.57+293540.5

TL;DR

This paper reports the discovery of a new quadruply imaged quasar from SDSS data, analyzing its lensing configuration and noting flux ratio anomalies that suggest small-scale structures in the lens.

Contribution

The paper presents the first identification and detailed analysis of a quadruply lensed quasar with observed flux ratio anomalies, indicating potential small-scale lens structures.

Findings

Discovery of a quadruply imaged quasar with 1.79" separation.

Standard mass models fit the image positions but not flux ratios.

Flux ratio discrepancies suggest small-scale lens structures.

Abstract

We report the discovery of a quadruply imaged quasar, SDSSJ125107.57+293540.5, selected from the Sloan Digital Sky Survey. Follow-up imaging reveals that the system consists of four blue point-like components in a typical cusp lens geometry surrounding a central red galaxy. The source redshift is 0.802 and the lens redshift is 0.410. The maximum image separation between the lensed components is 1"79. While the image configuration is well reproduced by standard mass models with reasonable parameter values, the flux ratios predicted by these models differ from the observed ratios in all bands. This is suggestive of small-scale structures in this lens, although the definitive identification of the anomaly requires more accurate photometry and astrometry.