A simple method to determine the time delays in presence of microlensing: application to HE 0435-1223 and PG1115+080

TL;DR

This paper introduces a straightforward method for measuring time delays in gravitationally lensed quasars that effectively accounts for microlensing effects, validated through simulations and applied to real quasar data.

Contribution

It presents a novel, simple approach based on orthogonal polynomial expansions to accurately determine time delays despite microlensing influences.

Findings

Successfully tested on simulated light curves from TDC0 campaign.

Provided new time delay estimates for HE 0435-1223 and PG 1115+080.

Results are consistent with previous studies, confirming method validity.

Abstract

A method for determining the time delays in gravitationally lensed quasars is proposed, which offers a simple and transparent procedure to mitigate the effects of microlensing. The method is based on fundamental properties of representation of quadratically integrable functions by their expansions in orthogonal polynomials series. The method was tested on the artificial light curves simulated for the Time Delay Challenge campaign TDC0. The new estimates of the time delays in the gravitationally lensed quasars HE 0435-1223 and PG 1115+080 are obtained and compared with the results reported by other authors earlier.