TY - JOUR
T1 - High-resolution imaging of two radio quasars at the end of the reionization epoch
AU - Perger, Krisztina
AU - Zhang, Yingkang
AU - Frey, Sándor
AU - An, Tao
AU - Gabányi, Krisztina E.
AU - Gurvits, Leonid I.
AU - Hwang, Chorng Yuan
AU - Koptelova, Ekaterina
AU - Paragi, Zsolt
AU - Wang, Ailing
N1 - Publisher Copyright:
© 2023 Sissa Medialab Srl. All rights reserved.
PY - 2023/8/22
Y1 - 2023/8/22
N2 - There are approximately 250 quasars discovered at redshift z ≥ 6, of which only a handful were detected in radio bands, and even fewer were imaged with the highest resolution very long baseline interferometry (VLBI) technique. Here we report the results of our dual-frequency observations with the Very Long Baseline Array (VLBA) of two such recently discovered quasars, VIKING J231818.35-311346.3 at z = 6.44 and FIRST J233153.20+112952.11 at z = 6.57. Both extremely distant sources were imaged with VLBI for the first time. The radio properties of the former are consistent with those of quasars with young radio jets. The latter has an UV/optical spectrum characteristic of BL Lac objects, of which no others have been found beyond redshift 4 so far. Our VLBA observations revealed a flat-spectrum compact radio source.
AB - There are approximately 250 quasars discovered at redshift z ≥ 6, of which only a handful were detected in radio bands, and even fewer were imaged with the highest resolution very long baseline interferometry (VLBI) technique. Here we report the results of our dual-frequency observations with the Very Long Baseline Array (VLBA) of two such recently discovered quasars, VIKING J231818.35-311346.3 at z = 6.44 and FIRST J233153.20+112952.11 at z = 6.57. Both extremely distant sources were imaged with VLBI for the first time. The radio properties of the former are consistent with those of quasars with young radio jets. The latter has an UV/optical spectrum characteristic of BL Lac objects, of which no others have been found beyond redshift 4 so far. Our VLBA observations revealed a flat-spectrum compact radio source.
UR - http://www.scopus.com/inward/record.url?scp=85150160922&partnerID=8YFLogxK
M3 - 會議論文
AN - SCOPUS:85150160922
SN - 1824-8039
VL - 428
JO - Proceedings of Science
JF - Proceedings of Science
M1 - 024
T2 - 15th European VLBI Network Mini-Symposium and Users' Meeting, EVN 2022
Y2 - 11 July 2022 through 15 July 2022
ER -