Estimation of time delays from two blended light curves of gravitational lenses

TL;DR

This paper presents a computational method to estimate time delays in gravitational lens systems from blended light curves, enabling analysis with modest observational equipment.

Contribution

The authors develop and test a new algorithm that recovers all time delays from two blended light curves assuming equal magnification ratios.

Findings

Successfully recovers time delays from simulated blended light curves.

Method works under the assumption of equal magnification ratios.

Applicable to modest observational data with limited resolution.

Abstract

Long time photometric monitoring programs of gravitational lens systems are often carried on using modest equipment. The resolution of such observations is limited and some of the images may remain unresolved. It may be still possible to find a full set of time delays from such a blended data. We discuss here a particular but interesting case when we have two light curves that both are blends. A suitable computational algorithm is developed and tested to work with computer-generated model light curves. Our method combines both blended sequences using the hypothetical time delays between the initial components of the light curves as free input parameters. The combined curves are then compared using statistical distance estimation. It occurs that using an assumption of equal magnification ratios between the components of the blends, we can indeed recover the whole set of time delays.