VLBI in China and the Collaboration with NL Zhi-Qiang Shen Shanghai Astronomical Observatory Chinese Academy of Sciences CAS-NWO Workshop on Radio Astronomy ( 24-25 April 2017, NAOC, Beijing, China )

VLBI Development in China 1970s VLBI Network Concept 1980s Shanghai 25m 1990s Urumqi 25m 2000s Beijing 50m & Kunming 40m + correlator pre-study of Space VLBI 2010s Shanghai 65m, FAST (500m), QTT 110m … Chinese VLBI Network 南山 Shanghai 65m (2012) FAST (2016)

VLBI in China It takes 30+ years (1975-2006) to establish the so-called Chinese VLBI network (CVN)! Nowadays, the CVN of five VLBI stations plus a correlation center has gradually performed astrophysical and geodetic observations as well as the VLBI tracking of space probes. Member of VLBI Networks: EVN, IVS, EAVN … Participating in international collaborations in sciences and VLBI technologies, long-term Dutch-Chinese collaboration in VLBI

CN-NL collaboration in the area of VLBI 1985 Nan Rendong worked Prof. Win Brouw & Richard Schilizzi @ the Netherlands Foundation for Radio Astronomy (NFRA) personnel exchanges in VLBI techniques (Rx engineers/technicians) and sciences (researchers) 2000s initiated various projects by Hong Xiaoyu & Leonid Gurvits & Richard Strom Members of EVN; JIVE board Supervision of joint PhD projects In 2009 NWO awarded JIVE-ShAO grant for collaboration in the development of the Next Generation VLBI correlator and Space Science VLBI applications 2010 Shen Zhiqiang & Zsolt Paragi continued the Dutch-Chinese collaboration, prioritized to well-focused research projects under the CAS-KNAW(Royal Netherlands Academy of Arts and Sciences)-CEP (China Exchange Programme) Black Holes at the highest resolution: Exploring the scientific potentials of the EVN and the emerging Chinese VLBI Network

VLBI topics for the March 2017 joint CAS-NWO call in the field of Radio Astronomy bilateral cooperation (Sino-Dutch) in more general terms with broader scientific/technological interests/areas than just one VLBI observing project or a single method compact structures on the smallest angular scales (through VLBI) NL: EVN, JIV-ERIC host SFXC CN: CVN/EVN Science Targets: FRB (localization/identification) space-crafts (tracking & navigation; space sciences ) SMBH shadow … Developments: VLBI with FAST digital backends/correlator, e-VLBI space VLBI (ultra-long wavelengths, millimeter ) Africa VLBI Network

Space Millimeter VLBI Array Main Scientific Objectives: High-resolution imaging of emission structure surrounding super-massive black hole (SMBH) to study SMBH Shadow (e.g. M87) Disk structure & dynamics, SMBH mass (water mega-masers) Astrophysical Jet in Active Galactic Nuclei (AGN) Specifications: Two 10-m (in diameter) space antennas Three frequency bands (8, 22 & 43 GHz) Dual polarization (LCP/RCP) Date rate (1.2 Gbps , or 2.4 Gbps) Angular resolution: 20 micro-arc-second Optimized orbits for a better (u,v) coverage Apogee: 60,000 km Perigee: 1,200 km Inclination: 28.5 deg Life time: 3 year 相关计划表加入到PPT中 6

Review Mtg @CAST in June 2016! High precision reflector: 10m diameter with a surface accuracy better than 0.4mm (RMS)