8-th VERA Userʼs Meeting, 16-17 Sep. 2010

東アジアVLBIネットワーク現状と観測に向けて
A. Miyazaki, S. Sawada-Satoh, H. Kobayashi, N. Kawaguchi(Mizusawa VLBI Observatory/NAOJ)
S.-S. Lee, B.W. Sohn, KVN group (KVN/KASI)
Z.-Q. Shen, Q.-B. Ling, SHAO VLBI group (SHAO/CAS)

BackgroundEast-Asia VLBI Network
Korea : KVN (Yonsei, Ulsan, Tamna)
China : CVN (Shanghai, Urumqi, Beijing, Kunming)
Japan : JVN (with VERA)
Diﬀerent recording systems and correlation processing
systems in each VLBI network. We are going to install“K4/VSOP terminal” in some antennas in Korea andChina in order to construct the ﬁrst phase East Asia
VLBI network.
In the future, wideband observation using Gbps recording
systems and the KJJVC.

East Asia VLBI Network array configuration

Mizusawa
Urumqi
Beijing

East Asia VLBI network✓ Korea : KVN✓ China : CVN✓ Japan : JVN (/ VERA)

Yonsei

Tamna
Shanghai

Kunmingmax. baseline ~6,000km

Ulsan

Ishigaki-jima

IrikiOgasawara

K4/VSOP terminal

Sampler
DFC-2000

Cassette changer
DMS-24

RecorderDIR-1000

Recording RateJVN : 128Mbps (16MHzBW, 2bit, 2ch)
max : 256Mbps (16MHzBW, 2bit, 4ch)

Korea：KVN
Antenna：21-m x３• Yonsei (延世 in Seoul)• Ulsan（蔚山）KVN Yonsei• Tamna (耽羅 in Jeju)
Frequency：(129/86GHz), 43/22GHz
Terminal：Mark5B,
DIR1000(K4)• 43/22GHz-bands receivers in Yonsei had installed in Oct. 2008.
• The receivers in Ulsan and Tamna have installed from Sep. to Oct. 2009.

Korea：KVN

DMS-24, Control PC, etc.
installed in KVN 3 station

KVN Yonsei
KVN Ulsan

Cassette changer
DMS-24

control PCDigital filter

KVN Tamna

China：Sheshan (Shanghai)

Sheshan 25-m

Antenna：25-m
Frequency：K, S/X, C, L -bands etc.
Terminal：MarkIV/VLBA,
Mark5A, Mark5B,K4(DIR1000)
Now 6.7GHz Methanol maser (C-band) receiver is available.

China：Sheshan (Shanghai)
Installation of K4/VSOP terminal system
in Sheshan station
Sheshan 25-m

VLBA terminal
Cassette changer
DMS-24Control PC
Sampler

Antenna console

Korea：KVN
KVN Yonsei KVN Ulsan KVN Tamna
Installation of K-4 terminal• KVN Yonsei & Ulsan（End of Oct. 2008）• KVN Tamna（Dec. 2008）
Fringe detection in test observations•1&3 Nov. 2008（K-band）
KVN Yonsei＋VERA KVN ﬁrst fringe detection @ K-band•12&13 Mar. 2009（Q-band）
KVN Yonsei＋VERA Fringe detection @ Q-band•16/23&22 Oct. 2009（K/Q-bands）
KVN Yonsei/Ulsan/Tamna＋VERA
KVN ３stations K/Q-band fringe detection

Test observation for system evaluation is carried out between KVN
and VERA.

KVN Yonsei-VERA K/Q-band
Nov 1, 2008

W49N

Nov 3, 2008

H2O maser

NRAO150First Fringe of KVN !

KVN Yonsei(Seoul) - VERA Mizusawa K-band
Mar 12, 2009 NRAO150
Mar 13, 2009 NRAO150

KVN Yonsei(Seoul) - VERA Mizusawa Q-band

KVN 3 antennas- VERAK/Q-band
Oct 16, 2009
・KVN internal baselines
・VERA-KVN baselines
Fringe detection !
Q-band obs. on Oct 22, 2009
Fringe detection !
KVN Yonsei/Ulsan/Tamna - VERA Iriki K-bandImaging of KVN-VERA: Continuum source
J0721+7120
Dec=+71.3deg

J0303+4716
Dec=+47.3deg

J0238+1636

J0825+0309

Dec=+16.6deg

Dec=+3.2deg

J0840+1312

J0501-0159Dec=+13.2deg

Dec=-2.0deg

Dec. 22, 2009KVN Yonsei, Ulsan - VERA 4 stations Q-bandImaging of KVN-VERA: Maser source
SiO maser
KVN+VERA (1hr)
I_rms = ~20 Jy/beam

Dec. 22, 2009
VERA (8hr) : previous obs.
I_rms = ~0.3 Jy/beamOrion KLSiO v=2

Kim et al. 2008
KVN Yonsei, Ulsan - VERA 4 stations Q-band

China：Sheshan (Shanghai)
Installation of K-4 terminal• Feb. 2009
Fringe detection in test observations•22 May 2009（K-band）
Sheshan 25-m
KVN Yonsei＋Sheshan＋VERAShanghai-KVN-VERA (EAVN) ﬁrst fringe detection•29 Nov. 2009（X-band）
Shanghai ＋JVN (VERA/Yamaguchi/Kashima)
X-band fringe detection•28&29 Aug. 2010（6.7GHz-band）
Shanghai ＋JVN
Scientiﬁc observation about methanol maser.
Waiting for the correlation process.

EAVN (China-Korea-Japan) K-band
KVN Yonsei - Mizusawa

Sheshan - KVN Yonsei

Sheshan - Mizusawa

May 22, 2009
NRAO150

Sheshan (Shanghai) - KVN Yonsei (Seoul) - VERAK-band

EAVN (China-Korea-Japan) K-band
Preliminary maps

May 22, 2009
UV coverage

NRAO150

3C236

Sheshan (Shanghai) - KVN Yonsei (Seoul) - VERA

K-bandShanghai-JVN X-band
Nov. 29, 2009
3C345
Sheshan - VERA Mizusawa

Sheshan - Yamaguchi

Sheshan (Shanghai) - Yamaguchi - VERA Mizusawa X-band
Sheshan - JVN(VERA, Yamaguchi 32-m, Kashima 34-m)

Shanghai-JVN X-band
Imaging

1928+738
VLBA 15GHz

UV coverage

Nov. 29, 2009
Clean map

Sheshan-JVN(VERA, Yamaguchi 32-m, Kashima 34-m)

Observing Frequency
and Antennas
VERA
Yonsei

KVN

Ulsan
Tamna
Shanghai

K4○○Q-band(43GHz)K-band(22GHz)○ fringe○ fringedetection

detection(2009/03)○ fringe(2008/11)○ fringedetection

detection(2009/10)(2009/10)○ fringe○CVN
otherJVN△（in the future）△（in the future）○ Waiting fordetection

detectioncorrelation(2009/05)（2009/11）
Urumqi, Kunming,(2010/08)

Kashima, Gifu,
Kashima, Nobeyama

C-band
(6.7GHz)○ fringe

Urumqi○X-band(8GHz)Tomakomai,
Tsukuba,(Yamaguchi, Ibaraki)

Beijing
Yamaguchi, Usuda,
Kashima, Tsukuba,
Uchinoura, (Ibaraki)

Yamaguchi, Usuda,Ibaraki

Present status
Recently/Near future for KVN- Terminal trouble in KVN
Ulsan DMS-24
Tamna DIR-1000

Now cassette tapes are changed by hand.
Spare recorder DIR-1000M in Feb 2010.

- KVN+VERA test observations every 1~2 months
Performance evaluation of KVN
Sensitivity check and Imaging test observations,
Geodesic observation to decide antenna position,
Phase reference observation, etc.
- System evaluation of KJJVC
Gbps recording for wideband observation andcorrelation process of Mark5B-DIR2000 using the KJJVC.
Gbps recording for KJJVC test
Parallel recording DIR-1000/DIR-2000 of VERA

Present status
Recently/Near future for CVN- Test observation with Shanghai=> Scientiﬁc observation
Methanol maser observations on the end of Aug. 2010
- Chinese second lunar satellite Chang'E-2（嫦娥2号）
Not available over half - one year
- Extension to the other chinese antennas
Urumqi (<= very long baseline), Kunming, Beijing
X K4/VSOP terminal ?
Mark5B recording and correlation process by KJJVC
Mark5B was installed in each antenna of CVN.
Under investigation of data format in CVN

FutureRecently/Near future- Regularly scientiﬁc observation
among KVN, Shanghai, and JVN/VERA- Key science / Project science for KVN+VERA array
Korea-Japan joint science WG

In the future- Common Use observation as the East Asia VLBI Network・KVN+VERA
・East Asia VLBI network (CVN+KVN+JVN/VERA)- Ground-based telescope array for VSOP-2

おしまい
East Asia VLBI Network array configuration

Mizusawa
Yonsei

Urumqi

BeijingKunming

UlsanTamna

Shanghai

Ishigaki-jimaIriki

Ogasawara