Summary of
KaVA/EAVN AGN
SWG activities

M. Kino (NAOJ/Kogakuin Univ) & BW Sohn (KASI)
on behalf of EAVN AGN SWG
2018/Sep

VERA Users Meeting 2018, at Mitaka

Science driverl What happens in the vicinity of black
holes (BHs)?
l M87 and Sgr A* are the best two targets
for looking into the vicinity of Black holes!
l KaVA-EAVN AGN SWG has focused on
M87 and Sgr A* since 2013~.

Tight collaboration with EHT-C
via M87 and Sg r A*VERA UM 2018

Publications using KaVA AGN LP (1st phase) data
1.
2.
3.
4.
5.

Performance evaluation of KaVA array with bright AGNs (2011 data)(Niinuma et al. 2014, PASJ).
Early result of KaVA pilot monitoring (during 2013-2014) at 22 GHz
conﬁrmed superluminal motions at sub-pc scale (Hada et al. 2017, PASJ).
Kinematics of 4C21.35 (during 2013-2014) (Lee T et al. 2018, MNRAS).
Scattering kernel of Sgr A* (one epoch in 2014) (Johnson et al. 2018, ApJ)

Detailed proﬁle of the velocity ﬁeld of M87 based on KaVA AGN LP(2015-2016 (Park et al. in prep).
6. The radial proﬁle of the spectral index map of M87 between 22 and 43 GHzwith KaVA AGN LP data (2015-2016) is investigated (Ro et al. in prep).
7.
Performance evaluation of EAVN (KaVA+Tia) w/ M87 data (Cui, Hada etal. in prep).
8. M87 kinematics during 2017 EAVN-EHT campaign data (Cui, Hada etal. in prep).
9. Performance evaluation of EAVN (KaVA+Tia) w/ Sgr A* data (Zhao et al. inprep).
10. Sgr A* long term monitoring (2013-2015) (Zhao et al. in prep)
11. etc

VERA UM 2018

News on 2017 EAVN-EHT campaign

M87 (1 mas = 140 Rs) is the best source for this study.

VERA UM 2018

!
VERA UM 2018

Cui, Hada+ in prep

Closer look at April 9th 2017

horizontal

EHT beam ~30 μas

super-resolution
w/ 0.2*0.4 mas

Cui, Hada+ in prep

Shortest interval (Apr 5th and 9th 2017)

Don’t miss the next talk by Y. Cui san!

VERA UM 2018

Persuade of non-Gaussianity inSgr A*

Sgr A*(1 mas = 100 Rs) is the unique source for thisstudy.

Long standing problem:“Observed radio images of Sgr A* isdominated by interstellar scattering.
So, an inference of Sgr A* image issensitive to an assumed scattering model.”Psaltis, Johnson+ 2018

Progress:a physically motivated model of interstellar scattering
red: 50 uas diameter

unscattered image
40 uas gaussian

Johnson+ 2018

KaVA 7mm data (2014 Nov) signiﬁcantly
contributes to constrain scattering kernel.

Zhao+ in prep

Longest baseline (OGA-TIA 300Mλ)detection in 2017 EAVN data!

!
200

250300VERA UM 2018

Further upgrade of EAVN
EAVN-high @ 3.5 mm

EAVN white paper

What’s next?

86GHz!

JSPS Grant-in-Aid for Scientiﬁc Research (A) Projects

JSPS Grant-in-Aid for Scientiﬁc Research (A) Projects

JSPS Grant-in-Aid for Scientiﬁc Research (A) Projects

JSPS Grant-in-Aid for Scientiﬁc Research (A) Projects

Upgrade of NRO45m:
VLBI backend system (PI: Niinuma-san) &Quasi-Optics (PI Imai-san)Don’t miss the relevant talk by Okada-san!

JSPS Grant-in-Aid for Scientiﬁc Research (A) Projects

ご支援のほどどうぞよろしくお願い申し上げますSummary of EAVN
AGN SWG activitiesl Wrapping up papers w/ 1st phase KaVA LP
data 2016-2017
ü both EAVN performance-evaluation of and KaVA
LP sciencel Development/Upgrade of EAVNü https://radio.kasi.re.kr/eavn/main_eavn.php
ü EAVN-high, NRO45

Timeline for W-band VLBI at NRO