activity
20092026
most citedDiscovery of a Perseus-like cloud in the early Universe: HI-to-H2 transition, carbon monoxide and small dust grains at zabs=2.53 towards the quasar J0000+0048

79 citations · 1k across the 62 of their papers we have counts for

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astro-ph.HE2025

SRG/eROSITA-SDSS view on the relation between X-ray and UV emission for quasars

S. A. Prokhorenko, S. Yu. Sazonov, M. R. Gilfanov +5

Motivated by the idea of using quasars as standardizable candles for cosmology, we examine the relation between X-ray (at 2 keV, ) and ultraviolet (at 2500 Angstrom,…

astro-ph.HE2024

X-Ray Variability of SDSS Quasars Based on the SRG/eROSITA All-Sky Survey

S. A. Prokhorenko, S. Yu. Sazonov, M. R. Gilfanov +6

We examine the long-term (rest-frame time scales from a few months to years) X-ray variability of a sample of 2344 X-ray bright quasars from the SDSS DR14Q Catalogue, bas…