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astro-ph.GA2022
Revisiting Andromeda's Parachute
Vyacheslav N. Shalyapin, Luis J. Goicoechea, Karianne Dyrland +1
The gravitational lens system PS J0147+4630 (Andromeda's Parachute) consists of four quasar images ABCD and a lensing galaxy. We obtained -band light curves of ABCD in the 2017$…
astro-ph.CO2022
A tale of two double quasars: Hubble constant tension or biases?
Luis J. Goicoechea, Vyacheslav N. Shalyapin
For a flat CDM (standard) cosmology, a small sample of gravitationally lensed quasars with measured time delays has recently provided a value of the Hubble constant in ten…