New optical light curves of PS J0147+4630

We obtained r-band light curves of ABCD in the 2017-2022 period from monitoring with two 2m class telescopes. Applying state-of-the-art curve-shifting algorithms to these light curves led to measurements of time delays between images, and the three independent delays relative to image D are accurate enough to be used in cosmological studies (uncertainty of about 4%): {Delta}t_AD_=-170.5{\pm}7.0, {Delta}t_BD_=-170.4{\pm}6.0, and {Delta}t_CD_=-177.0{\pm}6.5days, where image D is trailing all the other images.

Our finely sampled light curves and some additional fluxes in the years 2010-2013 also demonstrated the presence of significant microlensing variations. From the measured delays relative to image D and typical values of the external convergence, recent lens mass models yielded a Hubble constant that is in clear disagreement with currently accepted values around 70km.s^-1^Mpc^-1^. We discuss how to account for a standard value of the Hubble constant without invoking the presence of an extraordinary high external convergence.