activity
20192026
most citedSystematics and accuracy of VLBI astrometry: What can be learned from a comparison with Gaia Data Release 2

15 citations · 40 across the 8 of their papers we have counts for

collaborators

8 papers

astro-ph.GA2026

First Trigonometric Parallax Measurements with the KVN and VERA Array (KaVA)

Nobuyuki Sakai, Daisuke Sakai, Noriyuki Kawaguchi +26

To demonstrate the astrometric capability of the combined Korean VLBI (Very Long Baseline Interferometry) Network (KVN) and VLBI Exploration of Radio Astrometry (VERA) Array (KaVA)…

astro-ph.IM2024

Secular aberration drift in stellar proper motions: An additional term due to the change in line-of-sight direction

Niu Liu, Zi Zhu, Jia-Cheng Liu

The motion of the barycenter of the Solar System (SSB), the origin of the International Celestial Reference System, causes a directional displacement known as secular aberration. T…

astro-ph.EP2023★ 4 cited

Systematics of planetary ephemeris reference frames inferred from pulsar timing astrometry

Niu Liu, Ziu Zhu, John Antoniadis +2

This study aims to investigate the systematics in planetary ephemeris reference frames through pulsar timing observations. We used the published data sets from several pulsar timin…

astro-ph.IM2022★ 8 cited

Comparison of dynamical and kinematic reference frames via pulsar positions from timing, Gaia, and interferometric astrometry

Niu Liu, Zi Zhu, John Antoniadis +3

Pulsars are special objects whose positions can be determined independently from timing, radio interferometric, and Gaia astrometry at sub-milliarcsecond (mas) precision; thus, the…

astro-ph.IM2022

Evaluate the ICRF3 axes stability via extragalactic source position time series

Niu Liu, Sebastien Lambert, Felicitas Arias +2

We present an updated study on assessing the axes stability of the third generation of the International Celestial Reference Frame (ICRF3) in terms of linear drift and scatter base…

astro-ph.IM2021★ 2 cited

Evaluation of the ICRF stability from position time series analysis

Niu Liu, Sebastien Lambert, Felicitas Arias +2

The celestial reference frame is realized by absolute positions of extragalactic sources that are assumed to be fixed in the space. The fixing of the axes is one of the crucial poi…

astro-ph.IM2021★ 11 cited

Comparison of multifrequency positions of extragalactic sources from global geodetic VLBI monitoring program and Gaia EDR3

Niu Liu, Sebastien Lambert, Patrick Charlot +5

We extend previous works by considering two additional radio frequencies (K band and X/Ka band) with the aim to study the frequency dependence of the source positions and its poten…

astro-ph.IM2019★ 15 cited

Systematics and accuracy of VLBI astrometry: What can be learned from a comparison with Gaia Data Release 2

Niu Liu, Sebastien Lambert, Zi Zhu +1

We aim to investigate the overall properties of the ICRF3 with the help of the Gaia Data release 2 (Gaia DR2). This could serve as an external check of the quality of the ICRF3. Th…