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Astro -G, KVN/VERA(EAVN), VLBA, ALMA の現状と今後

Astro -G, KVN/VERA(EAVN), VLBA, ALMA の現状と今後. H.Kobayashi(NAOJ) 2011, Sep.,27 多波長で探る AGN ジェット研究会. ASTRO-G Mission. Dual pol. @ 8, 22, 43 GHz Phase-referencing capability Switching Maneuver 10 cm Orbit Determination. 9.3 m Antenna with high surface accuracy (0.4mm rms)

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Astro -G, KVN/VERA(EAVN), VLBA, ALMA の現状と今後

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  1. Astro-G, KVN/VERA(EAVN), VLBA, ALMAの現状と今後 H.Kobayashi(NAOJ) 2011, Sep.,27 多波長で探るAGNジェット研究会

  2. ASTRO-G Mission Dual pol. @ 8, 22, 43 GHz Phase-referencing capability Switching Maneuver 10 cm Orbit Determination 9.3 m Antenna with high surface accuracy (0.4mm rms) precision pointing (0.005deg) 1 Gbps Data Downlink Target Life Time is 3 years.

  3. Cancellation of Astro-G • 2009.3-7 PDR • Uncertainty of deployment antenna repeatability • Problems of surface accuracy (thermal conditions, radiation conditions) • 2009.7-2010.8 Tiger team activity • Only 1mm rms is achievable. • Cost will overrun more than 50% of initial cost. • 2010.9 ISAS Science council recommended the cancellation. • 2010.12 ISAS advisory council also recommended it. • 2011.09宇宙開発委員会での結論

  4. East Asian VLBI Network array

  5. Current working VLBI stations in Eastern Asia • Japan(13) • VERA(4), Kashima, Tsukuba, Yamaguchi, Nobeyama, Usuda, Tomakomai,Gifu,Uchinoura, Takahagi, Hitachi • Korea(3) • KVN (3) Yonsei, Ulsan, Tamna • China(4) • Shanghai, Urumqi, Beijin, Kumming • Shanghai 65m

  6. Feature of East Asia VLBI network • Largest number of VLBI stations • 8GHz 13 stations • 22GHz 19 stations • 43GHz 8 stations • S/X geodesy 13 stations • Phase referencing • VERA 2 beam system • KVN multi-frequency + fast nodding • Good UV coverage • Minimum baseline length ; 50 km • Maximum baseline length ; 5000 km

  7. Observation features • Phase referencing observations • VERA 2 beam • KVN multi-frequency • Nodding -> high sensitivity observations for low Tb objects (RQQ, SNR, Galactic objects) ->astrometry for maser sources (H2O,SiO,CH3OH..) • High dynamic range observations • Ground array of VSOP-2

  8. Total effective aperture and baseline length

  9. Current status of astrometry with VERA

  10. Japanese VLBI Network (JVN) • Collaboration • NAOJ (VERA) • Hokkaido, Ibaraki, Tsukuba, Gifu, Osaka-Pref, Yamaguchi, Kagoshima university • JAXA, NICT, GSI • 13 telescopes (11m ~ 64m) • Purpose • A new, characteristic VLBI array • A Base of East-Asian VLBI • Progress • Started in 2004 • Steady Observation in 2005 • First Paper published in 2006 • Observing time ~200 hr/yr • EAVN test observation

  11. Constructions of three stations were completed on Dec. 2008 ! Simultaneous Multi-Frequency Obs. -Phase Compensation, mm-VLBI

  12. Receiver Prototype 43 GHz Receiver * 86, 129 GHz Receivers will be installed.

  13. Seoul VLBI correlator center 8Gbps x 16 station Largest VLBI correlator Opened on May 13th, 2010

  14. New Correlator at Seoul • Joint development with Korea and Japan – VERA/Tape terminal Korea/China (Mark-5b) VERA/Disk (VOA) Optical fiber (VSI-E) Wideband correlator 8Gbps 16 stations ＶＬＢＩdata server Data processing and archive Software correlator 1Gbpsx4 stations Operation System

  15. Schedule • ２０１０　　 • Test Observations with VERA+KVN • 2011 • Start of science observations with Japan (VERA,JVN) /Korea (KVN), and Japan(JVN)/China(CVN). • 2012 • Start of science observations with Japan, Korea and China

  16. VLBA Operational Status Ongoing and Possible Future Upgrades • Walter Brisken • NRAO, Socorro

  17. Current capabilities of the VLBA • 45 baselines from 10 identical 25m antennas • Peak / sustainable record rate is 512 Mbps • 64 MHz/polarization with 2-bit samples • Operates at select bands between 330 MHz and 90 GHz • Dual band 2.2 / 8.4 GHz supported • 1-hour continuum sensitivity at 8.4 GHz = 54 Jy RMS • Angular resolution at 8.4 GHz is 1x2 mas

  18. Current capabilities of the VLBA • Absolute astrometry to a precision of 100 as • Relative astrometry to a precision of 10 as • Flexible correlation with DiFX • Can correlate at ~700 Mbps x 10 antennas for typical projects • 16 playback Mark5 units available • Transient processor

  19. VLBA Sensitivity Upgrade Project(http://www.vlba.nrao.edu/memos/sensi/) • Began as a project in 2007 • Three major components of the upgrade are: • New correlator • DiFX software correlator was ultimately chosen • New data recorder • Mark5C, developed by Haystack/Conduant/NRAO • New antenna back-end electronics • ROACH FPGA-based Digital Back End (RDBE) in development • Project funded (including media) to complete 2 Gbps capability • Funding from NRAO, NSF MRI grant and Conacyt (via UNAM) • Initial availability to astronomers anticipated this summer

  20. VLBA　運用継続問題 • NSF：　VLBA運用経費（６M$/yr)半分以上をnon-NSF fundで運用しないと2011年10月からBudget cut • 2011年2月　VLBA future WS • サポートの目標 (3M$/yr) • NRAO 1M$/yr 自助努力 ○ • Naval Obs. 1M$/yr -> daily UT1決定　○ • FERMI0.15 M$/yr • Shanghai 0.2 M$/yr　　○ • ASISS 0.2 M$/yr　　○ • MPIfRA 0.2 M$/yr　　申請中 • CSIRO/ICRUR 0.15 M$/yr • NAOJ 0.2 M$/yr

  21. VLBI長期計画の必要性 • 国内問題 • Astro-Gの中止 • 次期スペースVLBIを提案するのか、しないか？ • AGNなどの研究をどのように発展させるのか？ • 国際的なVLBIロードマップの必要性 • 多波長や電波の他分野に対するVLBIの存在意義の明確化 • ALMA、SKAとの関係 • VLBILarge programの戦略 • Global array構想の浮上 • VLBAの運用スキームの変更 • 東アジアVLBI観測網の開始 • VLBA/EVNなどとの棲み分け • 位相補償・高い周波数・・・・

  22. 長期計画の策定について • 研究目的を明確にする • 研究目標の設定　 • 実現性（装置性能・マンパワー）の検討 • 開発計画を明確にする • 周波数バンド • 記録帯域 • eVLBI • 予算計画

  23. 来年のEAVNシンポに向けて • Need considerations by each countries and groups • White papersof research subjects (What do we want?) • Development schedule (What can we do?) • Realistic operation plan (How much can we do?) • Need to start activities of Road map creation • Science goal • Development scope • Operation scheme

  24. ALMA project 15th of August: 18 antennas at the AOS

  25. ＡＬＭＡ　Ｃｙｃｌｅ-０　time allocation

  26. ALMA Schedule • 2011Sep.Start of Early Science • 2013Mar. 開所式 • 2014Jan.66台フル運用 • Antenna • 20122nd Quarter : EA 16台完 • 20131stQuarter　：　NA25台完 • 20133rd Quarter : EU 25台完

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