Astrometric Apparent Motion of High-redshift Radio Sources

被引：6

作者：

Titov, Oleg ^{[1
]}

Frey, Sandor ^{[2
,3
,4
]}

Melnikov, Alexey ^{[5
]}

Shu, Fengchun ^{[6
]}

Xia, Bo ^{[6
]}

Gonzalez, Javier ^{[7
]}

Tercero, Belen ^{[7
]}

Gurvits, Leonid ^{[8
,9
]}

de Witt, Aletha ^{[10
]}

McCallum, Jamie ^{[11
]}

Kharinov, Mikhail ^{[5
]}

Zimovsky, Vladimir ^{[5
]}

Krezinger, Mate ^{[2
,12
]}

机构：

[1] Geosci Australia, POB 378, Canberra, ACT 2601, Australia

[2] ELKH Res Ctr Astron & Earth Sci, Konkoly Observ, Konkoly Thege Miklos Ut 15-17, H-1121 Budapest, Hungary

[3] MTA Ctr Excellence, CSFK, Konkoly Thege Miklos Ut 15-17, H-1121 Budapest, Hungary

[4] Eotvos Lorand Univ, Inst Phys, Pazmany Peter Setany 1-A, H-1117 Budapest, Hungary

[5] Russian Acad Sci, Inst Appl Astron, Kutuzova Embankment 10, St Petersburg 191187, Russia

[6] Chinese Acad Sci, Shanghai Astron Observ, 80 Nandan Rd, Shanghai, Peoples R China

[7] Observ Yebes IGN, Apartado 148, E-19180 Yebes, Spain

[8] Joint Inst VLBI ERIC, Oude Hoogeveensedijk 4, NL-7991 PD Dwingeloo, Netherlands

[9] Delft Univ Technol, Fac Aerosp Engn, Kluyverweg 1, Delft, Netherlands

[10] South African Radio Astron Observ, 2 Fir St,Black River Pk, ZA-7925 Cape Town, South Africa

[11] Univ Tasmania, Hobart, Tas, Australia

[12] Eotvos Lorand Univ, Inst Geog & Earth Sci, Dept Astron, Pazmany Peter Setany 1-A, H-1117 Budapest, Hungary

来源：

ASTRONOMICAL JOURNAL | 2023年 / 165卷 / 02期

关键词：

VLBA CALIBRATOR SURVEY; POLARIZATION PROPERTIES; PROPER MOTIONS; LOUD QUASARS; INTERFEROMETRY; SPECTRA; LIMITS;

D O I：

10.3847/1538-3881/aca964

中图分类号：

P1 [天文学];

学科分类号：

0704 ;

摘要：

Radio-loud quasars at high redshift (z >= 4) are rare objects in the universe and rarely observed with Very Long Baseline Interferometry (VLBI). But some of them have flux density sufficiently high for monitoring of their apparent position. The instability of the astrometric positions could be linked to the astrophysical process in the jetted active galactic nuclei in the early universe. Regular observations of the high-redshift quasars are used for estimating their apparent proper motion over several years. We have undertaken regular VLBI observations of several high-redshift quasars at 2.3 GHz (S band) and 8.4 GHz (X band) with a network of five radio telescopes: 40 m Yebes (Spain), 25 m Sheshan (China), and three 32 m telescopes of the Quasar VLBI Network (Russia)-Svetloe, Zelenchukskaya, and Badary. Additional facilities joined this network occasionally. The sources have also been observed in three sessions with the European VLBI Network in 2018-2019 and one Long Baseline Array experiment in 2018. In addition, several experiments conducted with the Very Long Baseline Array in 2017-2018 were used to improve the time sampling and the statistics. Based on these 37 astrometric VLBI experiments between 2017 and 2021, we estimated the apparent proper motions of four quasars: 0901+697, 1428+422, 1508+572, and 2101+600.

引用

页数：12