activity
20242026
collaborators

7 papers

astro-ph.HE2026

The X-Ray Continuum Emission Region in the Lensed Quasar SDSS J133907.23+131038.6 is Much Smaller than the Accretion Disk

Christopher W. Morgan, James B. Margeson, Gilberto Garcia +4

We analyze microlensing variability in 15 seasons of optical monitoring data and 4 epochs of new X-ray observations of the doubly-imaged gravitationally lensed quasar SDSS J133907.…

astro-ph.GA2026

Joining forces: 30 years of optical monitoring of the Einstein Cross

V. N. Shalyapin, L. J. Goicoechea, R. Gil-Merino +5

We present an extended optical monitoring of the quadruply-imaged gravitationally lensed quasar QSO 2237+0305, the Einstein Cross, including observations from different observatori…

astro-ph.CO2026

Time-delay and lens galaxy redshift in the doubly imaged quasar PS J2305+3714

O. A. Burkhonov, V. N. Shalyapin, A. V. Sergeyev +6

We present results from a seven-season (2018-2024) monitoring campaign of the gravitationally lensed quasar system PS J2305+3714 using the 1.5-m Maidanak Telescope in the optical R…

astro-ph.GA2025

Primordial black holes in the main lensing galaxy of FBQ 0951+2635

Daniel Isla, Luis J. Goicoechea, Ana Esteban-Gutiérrez +4

Although dark matter in galaxies may consist of elementary particles different from those that make up ordinary matter and that would be smoothly distributed (still undetected), th…

astro-ph.GA2025

SDSS J1001+5027: Strong microlensing-induced chromatic variation caught in the act

Luis J. Goicoechea, Vyacheslav N. Shalyapin

We conducted long-term monitoring of the doubly imaged gravitationally lensed quasar SDSS J1001+5027 consisting of spectro-photometric observations separated by 120 days (tim…

astro-ph.GA2025

Optical+NIR analysis of a Newly Confirmed Einstein ring at z1 from the Kilo-Degree Survey: Dark matter fraction, total and dark matter density slope and IMF

Rui Li, Nicola R. Napolitano, Giuseppe D Ago +16

We report the spectroscopic confirmation of a bright blue Einstein ring in the Kilo Degree Survey (KiDS) footprint: the Einstein ``blue eye''. Spectroscopic data from X-Shooter at…