Key	  Science	  Observa/on	  	  of	  AGNs	  with	  KaVA	  array	  	M.	  Kino	  (KASI)	  &	  B.W.	  Sohn	  (KASI)	  on	  behalf	  of	  KaVA	  AGN	  sub-­‐WG	  	  	  VERA	  UM	  2014	  (NAOJ	  Mitaka)	

Announcement	  from	  directors	  (copy	  &	  paste	  of	  Honma-­‐san’s	  e-­‐mail)	

ScienOﬁc	  MoOvaOons	  lUnderstanding	  physical	  mechanism	  of	  AGN(BH)	  acOviOes	  in	  the	  Universe.	  
ltesOng	  “B-­‐driven	  jet	  paradigm”	  	  lprobing	  “real	  vicinity	  of	  BH”	  	  	  lexploring	  “universality	  &	  diversity	  of	  jets”	  KaVA	  KVN:	  	  3	  baselines	  （300	  –	  500	  km）	  +	  VERA:	  	  6	  baselines	  （1000	  -­‐	  2300	  km）	  =	  KaVA:	  	  21	  baselines	  （300	  –	  2300	  km）	  Synthesized	  beam	  of	  VERA	  &	  KaVA	  KaVA	  	  1010VERA	  	  h-10-10-5-50055e

10-0.2

500

0.2

0.4

-50.6

0.8

-10

101-0.2

5000.20.4-50.6-100.8

KaVA	  has	  a	  beauOful	  synthesized	  beam!	  It	  enables	  us	  to	  perform	  imaging	  analysis	  for	  extended-­‐jet	  structure.	  

1Imaging	  capability	  of	  KaVA	  3C273
010VERA 23 GHz(d)54Niinuma,	  Lee+	  (2014)	  in	  pJy/beamress	  0 (arXiv:1406.4356)	  2
43C273102013 Apr 13

513.5 pc

0

MilliArc seconds

MilliArc seconds

2Jy/beam-5-10

KaVA 23 GHz(e)2013 Apr 13
13.5 pc

0-5-10-15-15

Image rms = 14.2 mJy/beam
Peak = 5158.7 mJy/beam-20
50-5-10-15
MilliArc seconds-20-25Image rms = 4.0 mJy/beam
Peak = 5239.8 mJy/beam-20
50-5-10-15
MilliArc seconds-20-25

Dynamic	  Range	  is	  improved	  by	  a	  factor	  of	  3.	  	  VERA	  UM	  2014	

Key	  Science	  Program	  of	  AGN	  Sub-­‐WG	  M87	  (1	  mas	  =	  140	  Rs):	  	  tes/ng	  B-­‐driven	  jet	  paradigm	  Sgr	  A*(1	  mas	  =	  100	  Rs):	  probing	  real	  vicinity	  of	  SMBH	

TesOng	  “B-­‐driven	  jet	  	  paradigm”(1/2)	  GRMHD	  Model	  predicts	  jet-­‐acceleraOon	  around	  100~1000	  Rs.	  	  	  		  TesOng	  B-­‐driven	  jet	  paradigm	  (2/2):	  KaVA	  can	  probe	  “acceleraOon”-­‐zone!	

Distance	  from	  the	  core	  (mas)	  Hada (2014) finds a sign of acceleration
at 1~3mas region with VERA.

Date	  (year)	  Monthly monitoring @1~10mas by KaVA is the requirement.

Proving	  real	  vicinity	  of	  BH	  (1/4):	  KVN+VERA	  has	  beeer	  (u,v)	  coverage	  than	  VLBA+GBT	  @	  43GHz.	  	

KaVA	  VLBA+GBT	  Sgr	  A*	  vis.	  amp	  Sgr	  A*	  vis.	  amp	  Pink: KVN only
Orange: KaVA
Yellow: VERA only	

Pink: VLBA+GBT
Orange: VLBA only	Proving	  real	  vicinity	  of	  BH	  (2/4)	  With	  angular-­‐size	  of	  the	  radio	  core	  (θobs),	  	  Ue/UB	  is	  uniquely	  determined.	
Kino	  et	  al.	  (2014)	  ApJ,	  786,	  id.5	  	  Since the radio core of Sgr A* is the SSA-thick surface, SSA
turnover frequency is identical to the observing frequency itself.

Beeer	  measurements	  of	  θobs	  by	  KaVA	  is	  criOcal	  because	  Ue/UB	  has	  strong	  dependence	  on	  θobs.	  	  	  Proving	  real	  vicinity	  of	  BH	  (3/4):	  KaVA	  image	  of	  Sgr	  A*@43GHz,	  2013	  Oct	  7	  (by	  G.	  Zhao)	  	We	  are	  on	  the	  way	  of	  carefully	  checking	  of	  visibility	  data	  in	  details.	  	Proving	  real	  vicinity	  of	  BH	  (4/4):	  	  “Large-­‐When-­‐Brighter?”	

VERA measurement
by K. Akiyama+

KaVA is able to get better measurements of θobs. Then, we will clarify theorigin of the radio emission (RIAF? expanding plasma? jet? ).

Assignment	  of	  data	  analysis	  in	  AGN	  SWG	  (based	  on	  one’s	  performance	  and	  wishes)	

Inclusions	  of	  these	  AGN	  sources	  will	  tell	  us	  new	  insights	  on	  “universality	  &	  	  diversity	  of	  jets	  ”(structural	  evoluOon/magneOsm/radio/γ-­‐connecOons).	  	Summary	  1st	  paper	  showing	  KaVA	  imaging	  capability	  has	  been	  published	  (Niinuma,	  Lee	  et	  al.	  2014,	  PASJ,	  in	  press).	  Now,	  we	  go	  ahead	  with	  AGN	  KSP.	  	  	  l Towards	  understanding	  physical	  mechanism	  of	  AGN	  (BH)	  acOviOes	  in	  the	  Universe,	  we	  will	  ltest	  “B-­‐driven	  jet	  paradigm”	  (M87)	  lprobe	  “real	  vicinity	  of	  BH”	  	  (Sgr	  A*)	  lexplore	  “universality	  &	  diversity	  of	  jets”	  	  	  	  (4C39.25,	  4C21.35,	  3C379,	  	  M87,	  Sgr	  A*)	  Appendix

Estimate of request time (~180 hr/yr)
We started AGN f2f meeting at Mizusawa in 2012
July and in this Sci. meeting we present the current
version of of KaVA AGN KSP.
• M87@23GHz + three sources (80 hr/yr)– Monthly monitoring: 10epoch *8hr = 80 hr• Sgr A*@43GHz (60hr/yr)– Monthly monitoring: 10epoch *6hr = 60 hr• EHT campaign (40hr/yr)– Short monitoring (Spring): 5epoch *8hr = 40hr	  CombinaOon	  of	  M87	  &	  Sgr	  A*	  observaOons	  might	  be	  economical.	  (This	  is	  the	  way	  indeed	  used	  in	  EHT	  observaOons.)	  	  comment	  by	  Akiyama	Doeleman et al. (2008), Nature

measured & intrinsic sizes of Sgr A*	
measuredmajor-axis

Intrinsic
major-axis

λ^(1.44±0.07)

Lu et al. (2011) A&ASize-variability of Sgr A* (~10% level at Q-band)has been claimed. “Larger-When-Brighter”	

SNU	  team	  aims	  to	  prove	  	  “rapid	  structure	  evoluOon”.	

Yonsei	  Univ.	  team	  aims	  to	  	  “Young	  Radio	  Source	  4C39.25”.	

Long-term monitoring is by KaVA is essential
since young sources shows year-scale evolutions.
(See also Chida-san’s talk on
year-scale monitoring of 3C84 by GENJI!)