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Korean VLBI Network (KVN) and e -VLBI. Y. C. Minh, M.-G. Song, and H.-G. Kim Korea Astronomy Observatory. Contents Project Summary Special System Characteristics Science Targets Time Table System Configuration Site Construction: Yonsei, Ulsan, Tamna e-KVN. Project Summary.
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Korean VLBI Network (KVN) and e-VLBI Y. C. Minh, M.-G. Song, and H.-G. Kim Korea Astronomy Observatory Contents Project Summary Special System Characteristics Science Targets Time Table System Configuration Site Construction: Yonsei, Ulsan, Tamna e-KVN Busan APAN eScience: Minh, Song, & Kim
Project Summary • For the VLBI study of astronomy, • geodesy, and earth science: • KVN Observatories: • Radio Telescopes of 20m-diameter • VLBI Facilities at Seoul, Ulsan, and Jeju • Receiving Frequencies: • 22, 43, 100, 150 GHz • 2/8 GHz (for geodesy) • VLBI System: • DAS, Recorder, Correlator • Project Period: • 2001. 1. - 2007. 12. (7년) Busan APAN eScience: Minh, Song, & Kim
Special System Characteristics • Optimized to mm-VLBI: • High-precision antennas: • - High surface accuracy at 100-150 GHz • - High slew speed • Multi-channel Frontend Receivers: • - Low noise cryogenic HEMT receivers • - Multi-channel selections: 22, 43, 100, (150) GHz • Flexible and High-speed DAS: • - Selectable 4 IF streams of wide bandwidth • - High sampling rate of 2 Gsps, 4 bits/sample • Hard Disk-based Recorder and e-VLBI Performance Busan APAN eScience: Minh, Song, & Kim
Science Targets: Astronomical Key Projects Mira variable (Pulsating star) Diamond & Kemball • mm-VLBI • Insterstellar Maser study: • - SiO: Simultaneous 43, 86, (129) GHzObservations • - H2O, CH3OH maser lines • AGN Study: • - Surveys: Spectral indices at mm-wavelengths,.. • - Gamma-ray bursts, X-ray variables,.. • Astrochemistry: • - Absorption lines toward compact cores • - Interstellar molecule studies at mm-wavelengths • Gravitational Lensing • - Microlensing,.. Busan APAN eScience: Minh, Song, & Kim
Science Targets KVN Resolution: - ~0.001 arc-second at 100 GHz - 2mm at 500 km distance • Astronomical Targets: • From Cosmology to Solar System: • AGN, Quasar, Radio Galaxies, Jets, Gravitational Lens ,.. • Maser Lines: Star-forming regions, Stellar Envelopes ... • Interstellar Molecules, Astrochemistry ... • Geodesic Targets: • Reference Frames:ICRF, ITRF, CORE, .. • Tectonic Motions of Korea: Fault plans, Jeju island, .. • Earth Rotation, .. Busan APAN eScience: Minh, Song, & Kim
2001 2002 2003 2004 2005 2006 2007 Ⅰ Ⅱ Ⅲ Ⅳ Ⅰ Ⅱ Ⅲ Ⅳ Ⅰ Ⅱ Ⅲ Ⅳ Ⅰ Ⅱ Ⅲ Ⅳ Ⅰ Ⅱ Ⅲ Ⅳ Ⅰ Ⅱ Ⅲ Ⅳ Ⅰ Ⅱ Ⅲ Ⅳ Site Construction Site Selection Site Design Civil Engineering Works Building Construction KVN Research Center Const. Antenna Installation Specifications Contract Foundation Installation Calibration Receiver Development Design Preparation 22/42GHz Rx Manufacturing 2/8GHz Rx Manufacturing Test DAS Development Design Manufacturing Software Development VLBI Recorder Development Mk5 Development Manufacturing Installation Correlator Development Design Manufacturing Japan-Korea VLBI Experiments J-K 86 J-K 43GHz KVN Experiment KVN Construction Time Table Busan APAN eScience: Minh, Song, & Kim
System Configuration • KVN • Center • System/Observation Remote Control • Real-time & e-VLBI Operation/Data Synthesis Frontend Rxs KVN Correlator D A S IF Selector, BBC H-Maser Clock Sampler FIR, Formatter Recorder Recorder Recorder Recorder Busan APAN eScience: Minh, Song, & Kim
KVN Antennas • Slew Velocity: 3 o/sec (in AZ, EL) • Operating Range: • AZ: +270 o ~ -270 o • EL: 0 ~ 90 o • Tolerable Wind Speed: • Precision Observation: up to 10 m/s • Maximum Survival Velocity: 60, 90 m/s • Type: AZ/EL, Cassegrain focus • Diameter: 20m • Dish: Aluminum • Total Surface Tolerance: < 150 microm Busan APAN eScience: Minh, Song, & Kim
Front-end Receivers Low-Noise Cryogenic HEMT Receivers- 2/8 GHz: Geodesy - 22, 43, 100, 150 GHz: Astronomy - Multi-channel receivers: mm-VLBI: Phase correction Busan APAN eScience: Minh, Song, & Kim
DAS (VLBI Data Acquisition System) IF Inputs: Simultaneous Selection of up to 4 Ifs, Center Frequency: 3 GHz Bandwidth: 2 GHz High-speed Samplers: 2 Gsps, 4 bits per sample Digital Filters: 16 independent channels, 8/16/32 MHz BW Busan APAN eScience: Minh, Song, & Kim
KVN Recorder Hard-Disk Type VLBI Recorder: Mk 5 • MIT Haystack Observatory’s Mk5 Project: • Development Consortium(2001. 10.-2003. 10.): • MIT, NASA, NRAO, JIVE, BKG, MPI, KVN • Specifications: • 16 hard discs • maximum recording rate: 1 Gbps (expandable) • Standard PC and IDE hard discs • VSI Interface • KVN Production Plan of Mk 5 (2003~) Mk 5 Prototype (Mk5p) Busan APAN eScience: Minh, Song, & Kim
KVN Site Construction KVN Observatory Locations : - Seoul:Yonsei University - Ulsan:University of Ulsan - Jejudo:Tamna University KVN Data Center and Research Center : - Seoul:Yonsei University “KVN-Expanded”: a total of 6 antennas UV coverage and synthesized beam shape of the KVN+TRAO sites (for the Dec=40o source) Busan APAN eScience: Minh, Song, & Kim
KVN Yonsei Observatory Busan APAN eScience: Minh, Song, & Kim
KVN Ulsan Observatory Busan APAN eScience: Minh, Song, & Kim
KVN Tamna Observatory Busan APAN eScience: Minh, Song, & Kim
e-KVN • KVN: National Facility for VLBI (Very Long Baseline Interferometry) • Data syntheses using the data from remote sites: at present, from 4 sites in Korea, and possibly from foreign countries (e.g. Japan, Europe, USA, etc.) • To send the observed radio data: it will be very efficient, if using Information Infrastructures, instead of using postal mail of tapes and/or hard-disks. • DataRecording rate: 1 Gbps (> 2 Gbps) • Real-time/e-VLBI Operation: > 1 Gbps • Expected total amount of data to be sent: ~ a few Tbyte/day • KOREN: Busan APAN eScience: Minh, Song, & Kim
Status of KORENKorea Advanced Research Network • Special Features • Service for next generation Internet research environment (1999 ~), no commercial service • Service of latest internet technologies (IP Multicast, IPv6, etc.) • Small amount of annual fees, for research purposes • Data transfer rate: 155Mbps ~ 1Gbps (Local), 2.5 ~ 40Gbps (Backbone) • Equipment: IPv4, IPv6, IP Multicast, IP QoS, WDM, ATM Switches, Routers, Servers • Plan • All over the country: > 2.5 Gbps • Data speed between Korea-USA: 155 Mbps (2003. 7.) • Data speed between Korea-EU: to 45 Mbps (15 Mbps at present) Busan APAN eScience: Minh, Song, & Kim
GSR GSR GSR KOREN Singapore 6 M TAP Europe Seoul 10 M GSR USA 45 M Daegu Suwon GSR LEGEND GSR DWDM Daejon ATM Switch Router Gigabit Switch 1 G 40 Gbps Busan 2.5Gbps Japan 155Mbps > 2.5Gbps(plan) Gwangju Busan APAN eScience: Minh, Song, & Kim
vBNS, Abilene TEN-155 CA*net 3 KOREN Europe Canada TEIN 10G 10M Seoul NIO China 45M Suwon USA StarTAP Malaysia Daejon Daegu 622M×2 Busan 6M SingAREN Gwangju TransPAC Japan 1G Singapore 8M Tokyo-XP APII Test-bed (Asia Pacific Information Infra.) WIDE, JGN TEIN(Trans Eurasia Information Network) Busan APAN eScience: Minh, Song, & Kim
e-KVN Configuration Busan APAN eScience: Minh, Song, & Kim
e-KVN Summary • KVN: VLBI for Astronomy, Geodesy, and Earth Science - National Project • KVN Data Speed: 1 Gbps (2-4 Gbps at 2007) • Expected Use: ~a few Tbyte/day • Time Schedule for e-VLBI: - e-VLBI experiment between Japan-Korea: 2004 ~ - e-KVN: 2006 ~ • e-KVN: • - Radio Telescope Remote Control • - VLBI Observing Program Execution • - Real-time VLBI Operation: Interferometric fringe test, Real-time image • syntheses • - Domestic e-VLBI (IPoDWDM ?): Observed Radio Data Transfer, Quasi-real-time • Data Synthesis • - International e-VLBI Projects Busan APAN eScience: Minh, Song, & Kim