6 papers
Optical-morphology-based assessment of astrometric quality in Gaia-CRF3 quasars
Qiqi Wu, Shilong Liao, Zhaoxiang Qi +3
Context. Several studies have shown that host-galaxy structure or extended optical morphology in AGNs can induce spurious parallaxes and proper motions in Gaia DR3. However, it rem…
Refining the Gaia DR3 Parallax Zero-point: A Hybrid Approach Combining Global Parametric Correction with Local Refinement
Ye Ding, Shilong Liao, Zhaoxiang Qi +3
The Gaia Data Release 3 (GDR3) parallaxes are affected by a complex bias that depends on stellar magnitude, color, and celestial position, with amplitudes reaching tens of microarc…
Constraining the inclination of binary system orbits with the astrometric excess noise from Gaia DR3
Shilong Liao, Ye Ding, Shangyu Wen +2
Orbital inclination is crucial in determining the binary mass. The astrometric excess noise contains the orbital motion information, which can be used to constrain the inclination.…
A Gaia-linked High-purity QSO Candidate Catalog in Selected Fields with Extinction-binned Calibration and Spectrum-informed Training
Zi-Huang Cao, Zhao-Xiang Qi, Juan-Juan Ren +11
We present an extinction-calibrated, Gaia-source-level QSO candidate catalog for selected fields, designed as a high-purity input catalog for fiber-spectroscopic follow-up rather t…
Building a Radio AGN Sample from Cosmic Morning -- The Radio High-Redshift Quasar Catalog (RHzQCat): I. Catalog from SDSS Quasars and Radio Surveys at
Yingkang Zhang, Ruqiu Lin, Krisztina Perger +5
Radio-loud high-redshift quasars (RHRQs) provide crucial insights into the evolution of relativistic jets and their connection to the growth of supermassive black holes. Beyond the…
A pilot VLBI study of the SQUAB quasar sample featuring multiple Gaia detections
Yingkang Zhang, Tao An, Xiang Ji +5
Our previous work identified a class of SDSS quasars exhibiting multiple Gaia detections, classifying them as candidates for various astrophysical systems such as quasar-star pairs…