Busan APAN eScience: Minh, Song, & Kim 1

Y. C. Minh, M.-G. Song, and H.-G. KimKorea Astronomy Observatory

Korean VLBI Network (KVN)

and e-VLBI

Contents

Project Summary Special System Characteristics

Science TargetsTime Table

System ConfigurationSite Construction: Yonsei, Ulsan, Tamna

e-KVN

Busan APAN eScience: Minh, Song, & Kim 2

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. (7 년 )

Busan APAN eScience: Minh, Song, & Kim 3

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

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mm-VLBI

• Insterstellar Maser study: - SiO: Simultaneous 43, 86, (129) GHz Observations

- 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,..

Science Targets: Astronomical Key ProjectsMira variable (Pulsating star)

Diamond & Kemball

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Science Targets

Geodesic Targets: • Reference Frames: ICRF, ITRF, CORE, ..

• Tectonic Motions of Korea: Fault plans, Jeju island, ..

• Earth Rotation, ..

Astronomical Targets:

From Cosmology to Solar System:• AGN, Quasar, Radio Galaxies, Jets, Gravitational Lens ,..

• Maser Lines: Star-forming regions, Stellar Envelopes ...

• Interstellar Molecules, Astrochemistry ...

KVN Resolution: - ~0.001 arc-second at 100 GHz

- 2mm at 500 km distance

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KVN Construction Time Table

Site Construction

Antenna Installation

Receiver Development

2002

Ⅳ Ⅰ

2007

Ⅱ Ⅲ

Japan-Korea VLBIExperiments

CorrelatorDevelopment

VLBI RecorderDevelopment

DASDevelopment

ⅣⅢⅡⅠⅣⅢⅡⅠⅣⅢⅡⅠⅣⅢⅡⅠⅣⅢⅡⅠⅣⅢⅡⅠ

20062005200420032001

Site Selection SiteDesign

Civil EngineeringWorks

BuildingConstruction

KVN ResearchCenter Const.

Specifications Contract Foundation Installation Calibration

Design Preparation22/42GHz

Rx Manufacturing2/8GHz

Rx Manufacturing Test

Design Manufacturing Software Development

Mk5 Development Manufacturing Installation

Design Manufacturing

KVN ExperimentJ-K 43GHz86J-K

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Recorder

DAS

Recorder

FIR, Formatter

H-Maser Clock

Frontend Rxs

System Configuration

IF Selector, BBC

Sampler

RecorderRecorder

KVN

Center

• System/Observation Remote Control

• Real-time & e-VLBI Operation/Data Synthesis

KVN

Correlator

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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

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Rx 2 GHz 8 GHz 22 GHz 43 GHz 100 GHz 150 GHzFreq. Range 2.2~2.8 GHz 8~9 GHz 21.5~23.5GHz 42~44 GHz 85~115 GHz 120~150GHz

Rx Noise < 25 K < 25 K < 30 K < 50 K < 50 K --1st IF / BW 2.5G/600MHz 8.5G/1GHz 8.5G/2GHz 8.5G/2GHz 8.5G/2GHz 8.5G/2GHzIF Power -20 dBm -20 dBm -20 dBm -20 dBm -20 dBm -20 dBm

Polarization LCP/RCP LCP/RCP LCP/RCP LCP/RCP LCP/RCP LCP/RCP

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

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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

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KVN Recorder

Mk 5 Prototype (Mk5p)

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~)

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KVN Site Construction

KVN Observatory Locations :

- Seoul: Yonsei University - Ulsan: University of Ulsan - Jejudo: Tamna University

“KVN-Expanded”: a total of 6 antennas

KVN Data Center and Research Center : - Seoul: Yonsei University

UV coverage and synthesized beam shape of

the KVN+TRAO sites (for the Dec=40o source)

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KVN Yonsei Observatory

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KVN Ulsan Observatory

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KVN Tamna Observatory

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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.

Data Recording 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:

e-KVN

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Status of KOREN Korea 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)

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Seoul

KOREN

Daejon

Daegu

BusanGSR

GSR

GSR

GSR

USA

6 M

10 M

45 M

Japan

1 G

ATM Switch

155Mbps

2.5Gbps

Router

LEGEND

DWDM

40 Gbps

Gigabit Switch

> 2.5Gbps(plan)

TAP

GSR

GSR

Singapore

Europe

Suwon

Gwangju

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StarTAP

10G

CA*net 3

6M

SingAREN

Singapore

Canada

USA

622M×2

WIDE, JGN

Japan

Tokyo-XP

Seoul

Daejon

Gwangju

Busan

Daegu

8M

Suwon

TEN-155

10MNIO

TEIN

TransPAC

45M

vBNS, Abilene

APII Test-bed (Asia Pacific Information Infra.)

TEIN(Trans Eurasia Information Network)

1G

China

Malaysia

Europe KOREN

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e-KVN Configuration

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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

e-KVN Summary