Time Delay Cosmograpy of SDSSJ1433 with the 2.1m Wendelstein Telescope

Abstract

AbstractTime delay cosmography is based on the study of multiply gravitationally lensed images of a variable source. Their time delay differences are linearly dependent on the Fermat potential differences at the images’ positions and the Hubble parameter, whose exact value is to this date strongly debated in the framework of the Hubble tension. In this paper we present the study of SDSSJ1433, a quadruply lensed QSO, the time delays of which have been obtained after a 3-year observational campaign from the 2.1m Wendelstein telescope in the optical ǵ filter, and the corresponding mass model was constrained from multi-band archival HST observations. The resulting H0 value is $$77.4\frac{{km}}{{s\,Mpc}}$$ with a precision of∼ 6 %.