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SPIE, Orlando, May 2006, A. Szomoru, JIVE VLBI in Transition Arpad Szomoru Joint Institute for VLBI in Europe
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SPIE, Orlando, May 2006, A. Szomoru, JIVE EVN & JIVE European VLBI Network: collaboration of radio astronomy observatories in Europe, China, South Africa, USA Central correlator facility in Dwingeloo, the Netherlands: Joint Institute for VLBI in Europe Operations, user data Network support Visitor facilities Technology development
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SPIE, Orlando, May 2006, A. Szomoru, JIVE Principle of VLBI
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SPIE, Orlando, May 2006, A. Szomoru, JIVE
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Price recording media ($/GB)
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SPIE, Orlando, May 2006, A. Szomoru, JIVE Data Acquisition Move from tape to disk recording Reliability Cost Bandwidth Efficiency eVLBI: the next step No consumables Higher bandwidth Fast turn-around ToO support Disk based recording eVLBI using fiber
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SPIE, Orlando, May 2006, A. Szomoru, JIVE e-VLBI Proof-of-Concept Project DANTE/GÉANT Pan-European Network SURFnetDutch NREN GARR Italian NREN UKERNAUK NREN PSNC Polish NREN DFN German NREN KTHNOC/NORDUnet Nordic NREN Manchester UniversityNetwork application software JIVEEVN Correlator Westerbork telescopeNetherlands Onsala Space Observatory Sweden MROFinland MPIfRGermany Jodrell Bank UK TCfAPoland CNR IRA Italy
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SPIE, Orlando, May 2006, A. Szomoru, JIVE 0 SISI GRGR CZCZ IEIE LULU EEEE SKSK ILIL LTLTCYCY ESES HUHU ITIT FRFR UKUK BEBE NLNL DEDE SESE CHCH PTPT ATAT GEANT GEANT 2.5 G 1.2 G 622M 155 M BGBG LVLV RORO HRHR PLPL 45 M 34 M 310 M GÉANT: Access of NRENs to GÉANT EVN telescope
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SPIE, Orlando, May 2006, A. Szomoru, JIVE for the EVN and JIVE Standards:- Protocols, parameter tuning, procedures at telescope and correlator. New Capabilities:- Higher data rates, improved reliability, quicker response. for GÉANT and the NRENs To see significant network usage with multiple Gbit streams converging on JIVE. Minimum is three telescopes (not including Westerbork) Must be seen to enable new science and not just solve an existing data-transport problem Real-time operation is seen as the ultimate aim, buffered operation accepted as a development stage. POC targets:
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SPIE, Orlando, May 2006, A. Szomoru, JIVE
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Fibre pair from Amsterdam Optical Splitters GE lines to correlator LX Optics converters Cisco ONS 15252 Correlator Interface Current status: JIVE: 6 lambdas via Netherlight, each capable of 1 Gbps; 16 * 1 Gbps soon 1 Gbps connections to Westerbork, Torun, Onsala, Jodrell Bank, Medicina 155 Mbps to Arecibo, 128 to Cambridge Metsahovi being connected at 10 Gbps Current status: JIVE: 6 lambdas via Netherlight, each capable of 1 Gbps; 16 * 1 Gbps soon 1 Gbps connections to Westerbork, Torun, Onsala, Jodrell Bank, Medicina 155 Mbps to Arecibo, 128 to Cambridge Metsahovi being connected at 10 Gbps
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SPIE, Orlando, May 2006, A. Szomoru, JIVE
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First real-time eVLBI Image, 3 telescope observation of gravitational lens, May 2004 First eVLBI science observation, OH masers around IRC10420, Richards et al, Oct 2004 First broadband eVLBI science, detection of the Hypernova SN2001em, Paragi et al, astro-ph/0505468
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SPIE, Orlando, May 2006, A. Szomoru, JIVE Huygens descent tracking Detection of carrier signal during descent Salvage of Doppler experiment Building up experience with spacecraft tracking Special purpose, extreme narrow band software correlator Parachute flight dynamics
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SPIE, Orlando, May 2006, A. Szomoru, JIVE
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POC results Demonstration of feasibility Identification of problems Has led to closer ties with networking community and generated political interest Has laid the foundation for the next step forward (EXPReS)
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SPIE, Orlando, May 2006, A. Szomoru, JIVE The next step… e-VLBI & EXPReS I3 proposal to the EC (Communication & Network Development Call) Ranked first out of 43 proposals; nearly fully funded to an amount of 3.9 MEuro. EXPReS = EXpress Production Real-time e-VLBI Service
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SPIE, Orlando, May 2006, A. Szomoru, JIVE EXPReS aims Upgrade EVN to e-EVN 16 station real-time array Help solve last mile problem Including connections on a global scale Software in field and correlator to become real real-time Investigate/apply lambda switching And look beyond 1 Gb/s More capacity on digital sampling, more bandwidth As being implemented for eMERLIN in UK Hardware (PC-based) and protocols for transport Correlator with more capacity: distributed correlation
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SPIE, Orlando, May 2006, A. Szomoru, JIVE Expanding the e-VLBI Network
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SPIE, Orlando, May 2006, A. Szomoru, JIVE Field of View limitation Limited by t int Time smearing Shorter integrations Enable wide field surveys Study μJy sources Discriminate AGNs But, enormous increase of output data volume.. VLBI FoV x 100 6 arcmin [FWHP] Effelsberg beam
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SPIE, Orlando, May 2006, A. Szomoru, JIVE PCInt, high speed read-out VLBI field of view limited by correlator output rate New hardware enabling high speed parallel read-out of correlator boards to dedicated cluster Achieved 1/16s sampling At 24 MB/s data output Users seem to be ready for 800 GB data-sets…
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SPIE, Orlando, May 2006, A. Szomoru, JIVE Archive All output data on line Several TB, dominated by few projects Public one year after last epoch Together with calibration info All meta-data, schedules etc. Quality control plots Will need strategy to deal with data increase
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SPIE, Orlando, May 2006, A. Szomoru, JIVE RadioNet project JBO, MPIfR, ASTRON Addresses calibration issues for radio-interferometry, in particular VLBI Ionosphere, troposphere Improved data product with T sys and PC Data distribution selection tools Parallelization for large data sets eMERLIN, EVN and WSRT will produce user data sets of up to 1TB Focus on high-level parallelization Wide band and wide field imaging Advanced Long Baseline User Software
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SPIE, Orlando, May 2006, A. Szomoru, JIVE Conclusions eVLBI is changing the nature of VLBI Fast response, ToO capability better quality control, rapid data delivery New science, higher bandwidths Large fields of view Allows one to study μJy sources Or many masers over a large star formation region Data archive will contain millions of weak sources Introduction of new algorithms Improved calibration Methods to deal with vast data sets
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