Status and future of East Status and future of East Asia VLBI networkAsia VLBI network
H.Kobayashi(NAOJ)H.Kobayashi(NAOJ)2009.3.182009.3.18
East Asia VLBI WS@SeoulEast Asia VLBI WS@Seoul
Current working VLBI stationsCurrent working VLBI stations
Japan(13)Japan(13)• VERA(4), Kashima, Tsukuba, Yamaguchi, NobeyVERA(4), Kashima, Tsukuba, Yamaguchi, Nobey
ama, Usuda, Tomakomai,ama, Usuda, Tomakomai, Gifu,Gifu, Uchinoura, Uchinoura, Takahagi, HitachiTakahagi, Hitachi
Korea(3)Korea(3)• KVN (3) KVN (3) Seoul, Ulsan, JejuSeoul, Ulsan, Jeju
China(4)China(4)• Shanghai, Urumqi, Beijin, KummingShanghai, Urumqi, Beijin, Kumming• Shanghai 64mShanghai 64m
-> Possible largest array in the world
East VLBI Network array configuration
Feature of East Asia VLBI networkFeature of East Asia VLBI network
Largest number of VLBI stationsLargest number of VLBI stations• 8GHz 13 stations8GHz 13 stations• 22GHz 19 stations22GHz 19 stations• 43GHz 8 stations43GHz 8 stations
Phase referencingPhase referencing• VERA 2 beam systemVERA 2 beam system• KVN multi-frequency + fast noddingKVN multi-frequency + fast nodding
Good UV coverageGood UV coverage• Minimum baseline length ; 50 kmMinimum baseline length ; 50 km• Maximum baseline length ; 6000 kmMaximum baseline length ; 6000 km
Scientific objectives of EAVNScientific objectives of EAVN Astrometry and phase referencing VLBIAstrometry and phase referencing VLBI
• VERA + KVN : 20m x 7stations @22/43 GHzVERA + KVN : 20m x 7stations @22/43 GHz• JVN + CVN : methanol maser observation JVN + CVN : methanol maser observation
@[email protected] Sensitive imaging array @ 8/22 GHzSensitive imaging array @ 8/22 GHz
• JVN+KVN+CVN : >15 stations arrayJVN+KVN+CVN : >15 stations array• Ground array for VSOP-2 (2013 launch)Ground array for VSOP-2 (2013 launch)
Joint array with other networkJoint array with other network• Asian Pacific Telescope with LBAAsian Pacific Telescope with LBA• EVN + EAVN ; powerful global arrayEVN + EAVN ; powerful global array
East Asia VLBI consortium(under East Asia Core
Observatory Association)~ 2004
Japanese VLBI networkIncluding VERA Korean VLBI network
Chinese VLBI network
Assumption of Observation Time Assumption of Observation Time (2010~)(2010~)
EAVN 2,000 H/Y
2,500 2,5001,500
1,000Geodesy
1,000
1,000
KVN5,000 H/Y
VERA5,000 H/Y
Seoul 6,000 H/Y
Mitaka 2,500 H/Y
VSOP-2
Science (Dec. 5,2008)Science (Dec. 5,2008)
Results of VERA measurementsResults of VERA measurements
Sun
S269
Milky way galaxy
Illustration courtesy: NASA/JPL-Caltech/R. Hurt (SSC/Caltech)
NGC 281
NGC 281
ρ oph
S CrtOrion
NGC 1333
Sun neighborhood
VY CMa
Parallax + Proper motion Proper motion
Sgr A
OH43
W49NON2
Kaguya (RISE) missionKaguya (RISE) mission
Precise gravity field of moon
-> cooling time differences between farside and nearside
Takahagi/Hitachi; New VLBI stationTakahagi/Hitachi; New VLBI station
Takahagi/Hitachi
Kashima
Tsukuba
Usuda
100km
50km
200km
Takahagi/Hitachi
32m x 2
6-8GHz
22GHz
Sensitive array with short baselines
See Yonekura’s poster
Simultaneous Multi-Frequency Obs. -Phase Compensation, mm-VLBI
Constructions of three stations were completed on Dec. 2008 !
First fringe between Seoul and First fringe between Seoul and VERA@2008,308dVERA@2008,308d
1993 (25m)
1987(25m)
2006 (40m)
2006(50m)
Chinese VLBI NetworkChinese VLBI Network
2006
CorrelatorCorrelator
4 station software VLBI correlator4 station software VLBI correlator 5 stations hardware VLBI correlator5 stations hardware VLBI correlator
(128MHz bandwidth)(128MHz bandwidth)
e-VLBI (16Mbiteps) for 4 stations in e-VLBI (16Mbiteps) for 4 stations in 10 minutes 10 minutes
VLBI CorrelatorVLBI Correlator
Data reductionData reduction
Angle position calculationAngle position calculation
Orbit determinationOrbit determination
delay delay rate
R.A. Dec.
VLBI centerVLBI center
Chang’E satellite tracking as lunar mission succeeded
Lunar map obtained by Chang’E
FAST FAST (Five hundred meter Aperture Spherical radio Telescope)(Five hundred meter Aperture Spherical radio Telescope)
Korea-Japan Collaboration for new corKorea-Japan Collaboration for new correlator and data center developmentrelator and data center development
2005-20092005-2009• KASI and NAOJ signed MOU for developmentKASI and NAOJ signed MOU for development
Correlator at SeoulCorrelator at Seoul 8Gbps x 16 stations8Gbps x 16 stations UsageUsage
• KVNKVN• East Asia VLBI networkEast Asia VLBI network• VSOP-2VSOP-2
VERA
terminal
Korea/China
(Mark-V)
Japan Univ. (K-5)
Optical fiber
(VSI-E)
VLBI data server
Wideband correlator
8Gbps
16 stations Data processing and archive
Operation System
New Correlator at Seoul -Joint development with Korea and Japan –
Software correlator
1Gbpsx4 stations
VSOP-2VSOP-2
Talk of Doi-san
AGN accretion disk imagingAGN accretion disk imaging
AGN jet uniform schemeAGN jet uniform scheme
ConclusionConclusion
East Asia VLBI network has large possibilitEast Asia VLBI network has large possibilityy• 100 mas 100 mas ~ ~ 1010 μas (including VSOP-2)μas (including VSOP-2)• Around 20 stations are possible.Around 20 stations are possible.• CVN, KVN, JVN are started individually.CVN, KVN, JVN are started individually.• EAVN test observations have been started.EAVN test observations have been started.
Need actual organization scheme of observNeed actual organization scheme of observations and sciencesations and sciences