We started a follow-up investigation of the Deep X-ray Radio Blazar Survey objects with declination >-10 deg. We undertook a survey with the EVN at 5GHz to make the first images of a complete sample of weak blazars, aiming at a comparison between high- and low-power samples of blazars. All of the 87 sources observed were detected. Point-like sources are found in 39 cases, and 48 show core-jet structure. According to the spectral indices previously obtained, 58 sources show a flat spectral index, and 29 sources show a steep spectrum or a spectrum peaking at a frequency around 1-2 GHz. Adding to the DXRBS objects we observed those already observed with ATCA in the southern sky, we found that 14 blazars and a SSRQ, are associated to gamma-ray emitters. We found that 56 sources can be considered blazars. We also detected 2 flat spectrum NLRGs. About 50% of the blazars associated to a gamma-ray object are BL Lacs, confirming that they are more likely detected among blazars gamma-emitters. We confirm the correlation found between the source core flux density and the gamma-ray photon fluxes down to fainter flux densities. We also found that weak blazars are also weaker gamma-ray emitters compared to bright blazars. Twenty-two sources are SSRQs or CSSs, and 7 are GPSs. The available X-ray ROSAT observations allow us to suggest that CSS and GPS quasars are not obscured by large column of cold gas surrounding the nuclei. We did not find any significant difference in X-ray luminosity between CSS and GPS quasars.
Milliarcsecond-resolution Radio-imaging Survey of Blazar Candidates at 4 < z < 5.4
Konkoly Observatory, HUN-REN Research Centre for Astronomy and Earth Sciences（孔科利天文台，匈牙利研究与教育网络天文学与地球科学研究中心）；CSFK, MTA Centre of Excellence（匈牙利科学院卓越研究中心）；INAF – Osservatorio Astronomico di Brera（意大利国家天体物理研究所布雷拉天文台）；Dipartimento di Astronomia, Università di Bologna（博洛尼亚大学天文学系）；INAF – Istituto di Radioastronomia（意大利国家天体物理研究所无线电天文研究所）；Center for Astrophysics – Harvard & Smithsonian（哈佛-史密森尼天体物理中心）；Institute of Physics and Astronomy, ELTE Eötvös Loránd University（罗兰大学物理与天文学研究所）
本研究通过VLBI技术对4 < z < 5.4的高红移类Blazar候选体进行毫米弧秒分辨率射电成像调查，确认其Blazar性质并分析核心结构特征。
SKA-VLBI Probes of High-energy Emission Processes in Relativistic Jets
University of Manchester（曼彻斯特大学）；University of Bristol（布里斯托大学）；Max Planck Institute for Radio Astronomy（马克斯·普朗克射电天文研究所）；Joint Institute for VLBI ERIC（甚长基线干涉测量联合研究所）；University of Turku（图尔库大学）；Aalto University（阿尔托大学）
Polarization Angle Swings in Blazars Detected in the Millimeter-wave with the South Pole Telescope
University of Chicago（芝加哥大学）；Kavli Institute for Cosmological Physics, University of Chicago（芝加哥大学卡弗里宇宙物理学研究所）；Department of Astronomy and Astrophysics, University of Chicago（芝加哥大学天体物理系）；Fermi National Accelerator Laboratory（费米国家加速器实验室）；School of Physics, University of Melbourne（墨尔本大学物理学院）；Sorbonne Université（索邦大学）
