Chinese VLBA Programs and Chinese VLBI Network Xiaoyu
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 Si. O 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 B 3 1633+382 Y. Liu, D. R. Jiang, Z. -Q. Shen & M. Karouzos 2010 A&A FS QSO EGRET source z=1. 814 OVV 14 epochs of VLBI observations of B 3 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.
VLBA Monitoring of 1633+382 during a Major Millimeter-Flare Y. Liu, T. P. Krichbaum, J. A. Zensus & D. R. Jiang in preparation 1633+382: OVV, z=1. 814, core dominated 22 & 37 GHz gamma-ray bright AGN H. Teräsranta 90, 150 & 230 GHz major mm flare 2001 -2003. H. Ungerechts 3 C 345: QSO, z=0. 593, well known for its helical motion. 1749+096: BL Lac, z=0. 322, also very active QSO, and. VLBA a very monitoring compact mm-source.
Multiwaveband VLBA polarimetric observations of NRAO 530 Chen, 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 OQ 172 A High-z Laboratory for Studies of the Circumnuclear Environment Y. Liu, D. R. Jiang, L. Gurvits & A. B. Fletcher in preparation 3 VSOP images for high-z GPS High-z GPS (FFA/SSA) What is the GPS absorption mechanism? (FFA or SSA) the jet suffers a large band at ~ 3 mas Why is the jet strongly bent and curved, and how do physical properties vary along its length? the most compact region in the 4 mas map was resolved into two components Which is the core? extremely high rest-frame RM (RM>20, 000 rad m-2) very steep RM gradient (at 7 mas, RM<100 rad m-2) Hβ FWHM 3, 700 kms-1 3 x 108 M⊙ [O III] FWHM 2, 200 kms-1 What is the magnetic field topology? And why is the RM extremely high, and the inner jet depolarized? OQ 172 z=3. 522 0642+449 z=3. 396 0201+113 z=3. 639 multiband VLBA polarimetry observation
Studies of red supergiant Si. O masers with the VLBA — VX Sgr; 3 -epoch VLBA data at 1999 Apr. 24 Proper motion 1999 May. 23 1999 Apr. 31 ü Our observations provide the first direct evidence for an inward motion of S i O-m a s e r s h e l l a r o u n d a r e d supergiant. Chen, Shen, Imai & Kamohara 2006, Ap. J Φ=0. 75 -0. 80 Vinfall=4. 1 km/s ü The estimated distance of 1. 57± 0. 27 kpc to VX Sgr from the “statistical parallax” analysis to proper motions of Si. O masers. Chen, Shen & Xu 2007, Ch. JAA
Studies of red supergiant Si. O masers with the VLBA — AH Sco; 2 -epoch VLBA data 2004 Mar. 8 2004 Mar. 20 Chen & Shen 2008, Ap. J Model fitting: Proper motion Best-fit model for the Si. O maser kinematics in AH Sco ü V 1 = - 1 4 k m s- 1 a n d α ~ 0. 5 support the presence of a real inward flow in the Si. O maser region around AH Sco under the gravitation of the central star. ü 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 Si. O 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 06, Dec EPOCH 3 08, Aug 08, Feb EPOCH 1 EPOCH 2 EPOCH 4 EPOCH 5
4 epochs at 15, 43, and 86 GHz Helical jet structure driven by K-H instability : multiple jet bendings in 1156+295 on pc--kpc scales, derived from VLBA observations
1229 -021 VLA, VLBA images Hong et al. in preparation
Hot spot Nucleus Knotty radio jet of 3 C 48 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
L, C, S/X, K VLBI in China Major Facilities for RA in China S/X L, C(5/6 G), S/X, K 21 CMA Delingha 13. 7 m S/X L, C: 2012 K : ? Black: recent status L, C, S/X: 2012 Ku, K, Ka: Q: 2015 Yellow: plan L, C, X: 2014
• 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 e. VLBI, in 5 min. )
Digital BBC for 4 stations • 4 Processing Boards • One for data Selecting • 4 Ifs input, 2 GHz 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 KM BJ SH Network 34 Mbps 2)、数据传输网络 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 (256 Mbps) 2008 June 17: Shanghai –Australia & Japan (512 Mbps) 2009 January 6: Shanghai-Urumqi (256 Mbps) 2009 January 15 -16: IYA marathon obs. (Asia, Australia, Europe, America) 2009 February - : Shanghai 25 -m participates in the routine e. EVN sessions 23
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 24
Shanghai 65 m Radio Telescope • 65 -m in diameter fully steerable radio telescope • Active surface system • Cover 1. 4 – 46 GHz with 8 bands: – – – – L(1. 6 GHz) S/X(2. 3/8. 4 GHz) C(5 GHz) Ku(15 GHz) K(22 GHz) Ka(30 GHz) Q(43 GHz) • General-purpose (radio astronomy, geodynamics, single-dish, VLBI, • VLBI tracking for Chinese Lunar projects ) 25
Project Timeline • 2008:funded, contract to CETC 54 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 26
Some photos of the site
Active system parts
Structure of the antenna CETC 54
By the end of 2012 Thank you!
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