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Chinese VLBA Programs and Chinese VLBI Network. Xiaoyu HONG Shanghai Astronomical Observatory , CAS (xhong@shao.ac.cn). 2011.01.27. VLBA USERS in China. SHAO : D. R. Jiang , Z. Q. Shen, A. Tao, Y. Liu, X. Chen, Y. J. Chen, W. Zhao
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Chinese VLBA Programs and Chinese VLBI Network Xiaoyu HONG Shanghai Astronomical Observatory,CAS (xhong@shao.ac.cn) 2011.01.27
VLBA USERS in China • SHAO:D. R. Jiang,Z. Q. Shen, A. Tao, Y. Liu, X. Chen, Y. J. Chen, W. Zhao B. Zhang, W. H. Wang,X. Hong et al. • PMO: Y. Xu, et al. • NJU: X. W. Zheng, et al. • NAOC: H. Y. Zhang, C. J. Jin, R. D. Nan, B. Peng et al. • XJAO(Urumq): X. Liu et al. …
Sgr* A • Helical jet in AGNs • Radio jet of AGNs with gamma ray emission • Studies of red supergiant SiO masers • et al.
Z. Q. Shen, K. Y. Lo, M. C. Liang, P. T. P. Ho, J. H. Zhao. (Shen et al.. 2005, Nature)
A kinematic study of the compact jet in quasar B3 1633+382Y. Liu, D. R. Jiang, Z.-Q. Shen & M. Karouzos2010 A&A 14 epochs of VLBI observations of B3 1633+382 at 22 GHz with the VLBA two different possibilities of component classification two corresponding kinematical models are adopted to explain the tracks of the three components. One is a linear motion, while another is a helical model. FS QSO EGRET source z=1.814 OVV
VLBA Monitoring of 1633+382 during a Major Millimeter-Flare Y. Liu, T. P. Krichbaum, J. A. Zensus & D. R. Jiang in preparation 22 & 37 GHz H.Teräsranta 90, 150 & 230GHz H. Ungerechts VLBA monitoring 1633+382: OVV, z=1.814, core dominated gamma-ray bright AGN major mm flare 2001-2003. 3C345: QSO, z=0.593, well known for its helical motion. 1749+096: BL Lac, z=0.322, also very active QSO, and a very compact mm-source.
Multiwaveband VLBA polarimetric observations of NRAO530Chen, Shen, Feng, 2010,MNRAS Transverse Fractional Polarization (TFP): low in jet spine, high at edges Interpretation in helical magnetic fields: TFP: low in spine, high at edges (Lyutikov et al. 2005); Signature of bifurcation of EVPA at low and top Interpretation in magnetic compression and shear: Bottom and top EVPA: approximately parallel; Undetectable linear polarization in the middle (cancellation of emission from surface and deep magnetic) Color: Fractional Polarization Left contour: total intensity Right contour: linear intensity
Multifrequency VLBA Polarimetry of GPS Quasar OQ172 A High-z Laboratory for Studies of the Circumnuclear Environment Y. Liu, D. R. Jiang, L. Gurvits & A. B. Fletcher in preparation What is the GPS absorption mechanism? (FFA or SSA) Why is the jet strongly bent and curved, and how do physical properties vary along its length? Which is the core? What is the magnetic field topology? And why is the RM extremely high, and the inner jet depolarized? 0642+449 z=3.396 0201+113 z=3.639 multiband VLBA polarimetry observation 3 VSOP images for high-z GPS High-z GPS (FFA/SSA) the jet suffers a large band at ~3 mas the most compact region in the 4 mas map was resolved into two components extremely high rest-frame RM (RM>20,000 rad m-2) very steep RM gradient (at7 mas, RM<100 rad m-2) Hβ FWHM 3,700 kms-1 3x108M⊙ [O III] FWHM 2,200 kms-1 OQ172 z=3.522
Studies of red supergiant SiO masers with the VLBA • VX Sgr;3-epoch VLBA data at 1999 1999 Apr. 24 1999 May. 23 1999 Apr. 31 • Our observations provide the first direct evidence for an inward motion of SiO-maser shell around a red supergiant. Proper motion Chen, Shen, Imai & Kamohara 2006, ApJ • The estimated distance of1.57± 0.27 kpc to VX Sgr from the “statistical parallax” analysis to proper motions of SiO masers. Φ=0.75-0.80 Vinfall=4.1 km/s Chen, Shen & Xu 2007, ChJAA
Studies of red supergiant SiO masers with the VLBA • AH Sco; 2-epoch VLBA data • Chen & Shen 2008, ApJ 2004 Mar. 8 2004 Mar. 20 Model fitting: Proper motion Best-fit model for the SiO maser kinematics in AH Sco • V1=-14 km s-1 and α~0.5support the presence of a real inward flow in the SiO maser region around AH Sco under the gravitation of the central star . • The estimated distance d=2.26 kpc from the model fitting is in a good agreement with its near kinematic distance of about 2.0 kpc.
5 epochs VLBA Observations of SiO Masers around VX Sgr (Su et al. 2011, JAA, in press) VX Sgr: v=1 J=1-0, v=2 J=1-0 06,Jul 07,Aug 08,Aug EPOCH 1 06,Dec 08,Feb EPOCH 2 EPOCH 5 EPOCH 4 EPOCH 3
4 epochs at 15, 43, and 86GHz Helical jet structure driven by K-H instability : multiple jet bendings in 1156+295 on pc--kpc scales, derived from VLBA observations
Hot spot Nucleus Knotty radio jet of 3C48 revealed by the VLBA – indicative of jet-NIR clouds interactions – good case for studying AGN evolution and feedback Wilkinson et al. 1984; Feng et al. 2004; Worrall et al. 2005; An et al. 2010
Major Facilities for RA in China VLBI in China L,C,S/X,K S/X L,C(5/6G),S/X,K 21CMA Delingha 13.7m S/X L,C,S/X:2012 Ku,K,Ka:Q:2015 L,C:2012 K :? L,C,X:2014 Yellow:plan Black:recent status
Sheshan and Urumq are the full members if EVN and IVS
CVN --VLBI data processing center Hardware correlator (5 stations) Software correlator (10 stations) Output data: CE-1 format FITS format Software for CE-1 data processing (near real time eVLBI, in 5 min.)
Digital BBC for 4 stations • 4 Processing Boards • One for data Selecting • 4Ifs input, 2GHz total BW • 16 Ch output / VSI-H • 2 VSI-H interface • 1 / 2 / 4 bit output • Dual redundant system
VLBI tracking for Chang’E 1 &2 CE-1 CE -2
How VLBI work together with USB? 1)、VLBI测站 stations UR SH KM BJ 2)、数据传输网络 Network 34 Mbps 3)、VLBI中心 VLBI center VLBI data in 5 m Beijing center USB data
VLBI tracking for Chinese Lunar Project • VLBI plays important role for Chinese Lunar project. • VLBI is famous to people in China this moment. 2007.12 for CE-1 2010.12 for CE-2
e-VLBI 2007 August 28: Shanghai –Australia & Europe (256Mbps) 2008 June 17: Shanghai –Australia & Japan (512Mbps) 2009 January 6: Shanghai-Urumqi (256Mbps) 2009 January 15-16: IYA marathon obs. (Asia, Australia, Europe, America) 2009 February - : Shanghai 25-m participates in the routine eEVN sessions
CVN (Km+My+Sh+Ur) + Onsala 20-m + Medicina 32-m; 2009 Aug 5-6; 24 hr; X-band; 5 GPS sources JIVE Correlator CVN (An et al. 2010, in prep) 0129+560
Shanghai 65m Radio Telescope • 65-m in diameter fully steerable radio telescope • Active surface system • Cover 1.4 – 46 GHz with 8 bands: • L(1.6GHz) • S/X(2.3/8.4GHz) • C(5GHz) • Ku(15GHz) • K(22GHz) • Ka(30GHz) • Q(43GHz) • General-purpose (radio astronomy, geodynamics, single-dish, VLBI, • VLBI tracking for Chinese Lunar projects ) 25
2008:funded, contract to CETC54 for the antenna construction 2009: complete design, start manufacturing 2010: ground breaking, foundation completed 2011: antenna completed 2012: L/S/C/X band test observations, ready for participation in the Chinese Lunar Mission 2013-14: active surface tested, Ku/K/Ka/Q band test observations 2015: project accomplished, in full operation Project Timeline 26
Structure of the antenna CETC54
By the end of 2012 Thank you!