TY - JOUR
T1 - The impact of new estimates of models of stellar motion from VLBI on the alignment of the optically bright Gaia frame to ICRF3
AU - Lunz, Susanne
AU - Anderson, James M.
AU - Xu, Ming H.
AU - Heinkelmann, Robert
AU - Titov, Oleg
AU - Lestrade, Jean François
AU - Johnson, Megan C.
AU - Shu, Fengchun
AU - Chen, Wen
AU - Melnikov, Alexey
AU - McCallum, Jamie
AU - Lopez, Yulia
AU - Mikhailov, Andrei
AU - de Vicente Abad, Pablo
AU - Schuh, Harald
N1 - Funding Information:
The authors acknowledge use of the Very Long Baseline Array under the US Naval Observatory's time allocation. This work supports USNO's ongoing research into the celestial reference frame and geodesy. We thank also the Socorro correlator for reliably and quickly providing the correlated data. The National Radio Astronomy Observatory is a facility of the National Science Foundation operated under cooperative agreement by Associated Universities, Inc. This project is supported by the DFG grants No. SCHU 1103/7-2, No. HE 5937/2-2, and SCHU 1103/26-1. M. H. Xu was supported by the Academy of Finland project No. 315721. This work has made use of the data from the European Space Agency mission Gaia processed by the Gaia Data Processing and Analysis Consortium. Funding for the DPAC has been provided by national institutions, in particular the institutions participating in the Gaia Multilateral Agreement.
Funding Information:
The authors acknowledge use of the Very Long Baseline Array under the US Naval Observatory’s time allocation. This work supports USNO’s ongoing research into the celestial reference frame and geodesy. We thank also the Socorro correlator for reliably and quickly providing the correlated data. The National Radio Astronomy Observatory is a facility of the National Science Foundation operated under cooperative agreement by Associated Universities, Inc. This project is supported by the DFG grants No. SCHU 1103/7-2, No. HE 5937/2-2, and SCHU 1103/26-1. M. H. Xu was supported by the Academy of Finland project No. 315721. This work has made use of the data from the European Space Agency mission Gaia processed by the Gaia Data Processing and Analysis Consortium. Funding for the DPAC has been provided by national institutions, in particular the institutions participating in the Gaia Multilateral Agreement.
Publisher Copyright:
© Copyright owned by the author(s) under the terms of the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License (CC BY-NC-ND 4.0).
PY - 2021
Y1 - 2021
N2 - The reference frame determined by Gaia EDR3, Gaia-CRF3, is aligned to the International Celestial Reference System by referring to counterparts in its latest realization, the third International Celestial Reference Frame (ICRF3), which is calculated from very long baseline interferometry (VLBI) observations of extragalactic objects at radio frequencies. The objects in ICRF3, although bright at radio frequencies, are mostly faint at optical frequencies. The non-rotation of the optically bright Gaia frame to ICRF3 has to be tested separately because the Gaia dataset is known to be magnitude-dependent in terms of astrometric calibration. This can be done by identifying additional counterparts besides objects in ICRF3. Suitable counterparts are radio stars observed by VLBI relative to extragalactic objects in ICRF3 using phase-referencing. We discuss the rotational differences, i.e., orientation and spin, between the optically bright Gaia EDR3 and models of stellar motion from VLBI. In particular, we show the effects of improved models of stellar motion, for which we extended the time series from literature or archives with new VLBI results.
AB - The reference frame determined by Gaia EDR3, Gaia-CRF3, is aligned to the International Celestial Reference System by referring to counterparts in its latest realization, the third International Celestial Reference Frame (ICRF3), which is calculated from very long baseline interferometry (VLBI) observations of extragalactic objects at radio frequencies. The objects in ICRF3, although bright at radio frequencies, are mostly faint at optical frequencies. The non-rotation of the optically bright Gaia frame to ICRF3 has to be tested separately because the Gaia dataset is known to be magnitude-dependent in terms of astrometric calibration. This can be done by identifying additional counterparts besides objects in ICRF3. Suitable counterparts are radio stars observed by VLBI relative to extragalactic objects in ICRF3 using phase-referencing. We discuss the rotational differences, i.e., orientation and spin, between the optically bright Gaia EDR3 and models of stellar motion from VLBI. In particular, we show the effects of improved models of stellar motion, for which we extended the time series from literature or archives with new VLBI results.
UR - http://www.scopus.com/inward/record.url?scp=85129775746&partnerID=8YFLogxK
M3 - Conference article
AN - SCOPUS:85129775746
SN - 1824-8039
VL - 399
JO - Proceedings of Science
JF - Proceedings of Science
M1 - 032
T2 - European VLBI Network Symposium and Users Meeting
Y2 - 12 July 2021 through 14 July 2021
ER -