83 citations · 603 across the 24 of their papers we have counts for
6 papers · 1 filter
Gaia parallax bias via spherical harmonics: A Python tool and discussion of possible causes
Valeri V. Makarov, Ciprian T. Berghea
Parallaxes in Gaia DR3 are known to suffer from a complex set of sky-correlated and magnitude-dependent offsets or biases at the level of a few tens of as. Estimated from a samp…
A Highly Magnified Gravitationally Lensed Red QSO at z = 2.5 with a Significant Flux Ratio Anomaly
Eilat Glikman, Cristian E. Rusu, Geoff C. -F. Chen +12
We present the discovery of a gravitationally lensed dust-reddened QSO at z = 2.517, identified in a survey for QSOs by infrared selection. Hubble Space Telescope imaging reveals a…
The precious set of radio-optical reference frame objects in the light of Gaia DR2 data
Valeri V. Makarov, Ciprian T. Berghea, Julien Frouard +2
We investigate a sample of 3412 {\it International Celestial Reference Frame} (ICRF3) extragalactic radio-loud sources with accurate positions determined by VLBI in the S/X band, m…
A Search for Gravitationally Lensed Quasars and Quasar Pairs in Pan-STARRS1: Spectroscopy and Sources of Shear in the Diamond 2M11342103
Cristian E. Rusu, Ciprian T. Berghea, Christopher D. Fassnacht +4
We present results of a systematic search for gravitationally lensed quasars in Pan-STARRS1. Our final sample of candidates comprises of 91 systems, not including 25 rediscovered l…
Discovery of the first quadruple gravitationally lensed quasar candidate with Pan-STARRS
C. T. Berghea, G. J. Nelson, C. E. Rusu +2
We report the serendipitous discovery of the first gravitationally lensed quasar candidate from Pan-STARRS. The grizy images reveal four point-like images with magnitudes between 1…
Astrometric evidence for a population of dislodged AGN
Valeri V. Makarov, Julien Frouard, Ciprian T. Berghea +5
We investigate a sample of 2293 ICRF2 extragalactic radio-loud sources with accurate positions determined by VLBI, mostly active galactic nuclei (AGN) and quasars, which are cross-…