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An Interesting Story of Gamma-Ray Bright AGNs by the iMOGABA and AiMOGABA (A KVN Key Science Program) Sang-Sung Lee (KASI) and the iMOGABA team 2018 September 6 East Asia VLBI Workshop Pyeoung Chang :

  1. An Interesting Story of Gamma-Ray Bright AGNs 
 by the iMOGABA and … AiMOGABA 
 (A KVN Key Science Program) Sang-Sung Lee (KASI) and the iMOGABA team 2018 September 6 East Asia VLBI Workshop Pyeoung Chang

  2. 출처: http://server7.wikisky.org/snapshot? M87 (Virgo) img_size=&img_res=&ra=12.5138&de=12.3896&angle=0.0293&projection=tan& rotation=0.0&survey=astrophoto&img_id=905632&width=2160&height=2160 &img_borders=&interpolation=bicubic&jpeg_quality=0.8 Spectrum of NGC 1068 
 http://homework.uoregon.edu/pub/class/321/sspher.html The Discoveries • Discoveries of non-stellar activities – Strong broad emission line in NGC 1068 
 (Fath 1909) – Jet in M87 (Curtis 1918 ): 
 apparently connected with the nucleus 
 by a thin line of matter 


  3. Unified scheme of AGN Blazars… Doppler boosted, violent 
 (Angel & Stockman 80) Graphic courtesy of Marie-Luise Menzel (MPE)

  4. AGNs visible on Gamma-ray sky 75 % are blazars Ajello+17

  5. Scientific Goals • Studying the origins of the gamma-flares – What is the location of the gamma-ray flares? : Down stream the relativistic jets? (e.g., an orphan flare) : much inner region of the jets? (e.g., radio counter part time-lagged) – What cause the gamma-ray flares of AGNs? : A relativistic jet of high energy plasma (e.g., Marscher et al. 2008) : Doppler boosting of synchrotron radiation of the jet (e.g., Dermer 1995) : Inverse Compton scattering by relativistic electrons

  6. Origins of Gamma-ray Flares in AGNs 
 (A KVN Key Science Program) • Project I (Single Dish): MOGABA (Monitoring of Gamma-ray Bright AGNs) – radio polarization light curves after a gamma-ray flare of 32 AGNs – dense monitoring at 22, 43, 86 (129) GHz – weekly monitoring for 3-4 months – Lee et al. 2013, Kang et al. 2015, JKAS, 48, 257 (Case study for 3C 279) • Project II (VLBI): iMOGABA (Interferometric MOGABA) – Monthly VLBI monitoring of the MOGABA sources ( ~34 ) – correlated flux of inner-jet structure after gamma-ray flare – Multi-freq. (22/43/86/129GHz) monitoring – Requirement: 
 accurate amplitude calibration with careful Tsys measurements 
 (antenna gain measurement every hour) – Lee et al. 2016, ApJS, 227, 8 (Project overview and single-epoch results)

  7. Collaborations of our KSP (17 people) including 6 students + 5 postdocs • KASI (Korea) – Do-Young Byun (MOGABA data reduction pipeline) – Jeffrey Hodgson (iMOGABA data reduction pipeline, 3C84) – Sincheol Kang (MOGABA observations/data reduction, iMOGABA data reduction,1156+295) – Jeong-Sook Kim (CygX-3) – Sang-Hyun Kim (MOGABA observations/data reduction, iMOGABA data reduction, CTA102) – Soon-Wook Kim (CygX-3) – Jee Won Lee (iMOGABA data reduction, 0716+714/OJ287) – Sang-Sung Lee (PI) – Kiyoaki Wajima (iMOGABA data reduction, faint AGNs) – Guangyao Zhao (iMOGABA with frequency phase transfer) 
 • Seoul National University (Korea) – Juan-Carlos Algaba-Marcos (iMOGABA data reduction, 1633+382) – Dae-Won Kim (iMOGABA data reduction, BL Lac/1749+096) – Jongho Park (iMOGABA data reduction, 1510-089) – Sascha Trippe (bright AGNs) 
 • Chungbuk National University (Korea) – Sung-Min Yoo (iMOGABA data reduction, 3C 279) 
 • Kogakuin University (Japan) – Motoki Kino (bright AGNs) 
 • MPIfR (Germany) – Jae-Young Kim (iMOGABA data reduction, M87)

  8. 
 
 References • Published (16 SCI papers, since 2015) – First detection of 350 micron polarization of 3C 279 (Lee et al. 2015, ApJL ) – iMOGABA II: Frequency Phase Transfer (Algaba et al., 2015 JKAS, 14 citations ) – Amplitude correction factors of KVN (Lee et al. 2015 JKAS, 14 citations ) – Polarization monitoring of 3C 279 (Kang et al. 2015 JKAS, 7 citations ) – The KVN Pipeline (Hodgson et al. 2016 JKAS, 9 citations ) – Detection of mm polarization IDV of S5 0716+714 (Lee et al. 2016 A&A Letter ) – iMOGABA I: Single-epoch imaging results (Lee et al. 2016 ApJS ) – Proving the gamma-ray IDV in 3C279 (Rani et al. 2017 MNRAS ) – iMOGABA : S5 0716+714 (Lee et al. 2017 ApJ ) – iMOGABA : BL Lac (Dae-Won Kim et al. 2017 JKAS, 3 citations ) – iMOGABA : 1633+382 I (Algaba et al. 2018 ApJ ) : highlights – iMOGABA : FPT2 (Zhao et al. 2018 AJ ) : highlights – iMOGABA : 3C 84 (Hodgson et al. 2018 MNRAS ) : highlights – iMOGABA : M87 (Jae-Young Kim et al. 2018 A&A Letter ) : highlights – iMOGABA : 1633+382 II (Algaba et al. 2018 ApJ ) – iMOGABA : 1749+096 (Dea-Won Kim et al. 2018 MNRAS ) 


  9. 
 
 References • Published (16 SCI papers, since 2015) – First detection of 350 micron polarization of 3C 279 (Lee et al. 2015, ApJL ) – iMOGABA II: Frequency Phase Transfer (Algaba et al., 2015 JKAS, 14 citations ) – Amplitude correction factors of KVN (Lee et al. 2015 JKAS, 14 citations ) – Polarization monitoring of 3C 279 (Kang et al. 2015 JKAS, 7 citations ) Student – The KVN Pipeline (Hodgson et al. 2016 JKAS, 9 citations ) (UST) – Detection of mm polarization IDV of S5 0716+714 (Lee et al. 2016 A&A Letter ) – iMOGABA I: Single-epoch imaging results (Lee et al. 2016 ApJS ) – Proving the gamma-ray IDV in 3C279 (Rani et al. 2017 MNRAS ) – iMOGABA : S5 0716+714 (Lee et al. 2017 ApJ ) – iMOGABA : BL Lac (Dae-Won Kim et al. 2017 JKAS, 3 citations ) Student (SNU) – iMOGABA : 1633+382 I (Algaba et al. 2018 ApJ ) : highlights – iMOGABA : FPT2 (Zhao et al. 2018 AJ ) : highlights – iMOGABA : 3C 84 (Hodgson et al. 2018 MNRAS ) : highlights – iMOGABA : M87 (Jae-Young Kim et al. 2018 A&A Letter ) : highlights Student (SNU) – iMOGABA : 1633+382 II (Algaba et al. 2018 ApJ ) – iMOGABA : 1749+096 (Dae-Won Kim et al. 2018 MNRAS ) 
 Student (SNU)

  10. Upcoming papers • Submitted (1 SCI papers) – iMOGABA : Core-blending effect I (Algaba et al. JKAS special issue 2018 ) 
 • In preparation (11 SCI papers) – iMOGABA : Evaluation of imaging quality (Wajima et al. JKAS ) Student – iMOGABA : 1156+295 (Kang et al. ApJ ) : See the poster by Kang, Sincheol (UST) – iMOGABA : OJ 287 (Lee et al. ApJ ) : See the poster by Lee, Jee Won – iMOGABA : Core-blending effect II (Lee et al.) – iMOGABA : Variability time scales (Lee et al.) Student – iMOGABA : 1510-089 (Park et al. ApJ ) (SNU) – MOGABA : S5 0716+714 (Kang et al. ApJ ) Student – MOGABA : 3C 454.3 (Lee et al. ApJ ) (UST) – MOGABA : Multi-frequency Polarization Survey (MFPOL) (Lee et al. ApJ ) Student – iMOGABA : CTA 102 (Kim et al. ApJ ) (UST) – iMOGABA : 3C 279 (Yoo et al. ApJ ) 
 Student (CNU)

  11. Highlight 1. FPT envies FPT-square Zhao et al. 2018, AJ FPT-square (cf. FPT=Frequency Phase Transfer) – implementing a further phase transfer between two FPT residuals (i.e., calibrating dispersive effect) – Increase the coherence time up to 8 hr (i.e., much higher sensitivity) phase phase solution solution after 
 after 
 FPT FPT-square FPT-square can help to detect/image sources at high (>43 GHz) frequencies – Successfully performed with iMOGABA – Suitable also for high frequency all-sky survey (e.g., MASK)

  12. Hightlight 2. A Sad Orphan Gamma-ray Flare Dae-Won Kim et al. 2017, JKAS We observed BL Lacertae - 2013 Jan - 2016 Mar 
 - a radio loud AGN (< 9 Jy) 
 - gamma-ray bright - two outbursts on 2013/2015 KVN images No radio counter parts - gamma-ray downstream the jet - radio counterparts under a https://fermi.gsfc.nasa.gov/ssc/data/ variability access/lat/msl_lc/source/BL_Lac - variation of Doppler boosting - actually no radio counter part (a sad orphan flare) A sad orphan flare might occur due to inverse Compton scattering by seed photons from e.g., a jet sheath (ring of fire model) 


  13. Hightlight 2. A Sad Orphan Gamma-ray Flare Dae-Won Kim et al. 2017, JKAS We observed BL Lacertae - 2013 Jan - 2016 Mar 
 - a radio loud AGN (< 9 Jy) 
 - gamma-ray bright - two outbursts on 2013/2015 KVN images No radio counter parts - gamma-ray downstream the jet - radio counterparts under a https://fermi.gsfc.nasa.gov/ssc/data/ variability access/lat/msl_lc/source/BL_Lac - variation of Doppler boosting - actually no radio counter part (a sad orphan flare) A sad orphan flare might occur due to inverse Compton scattering by seed photons from e.g., a jet sheath (ring of fire model) 


  14. Highlight 2. A Sad Orphan Gamma-ray Flare Dae-Won Kim et al. 2017, JKAS We observed BL Lacertae - 2013 Jan - 2016 Mar 
 - a radio loud AGN (< 9 Jy) 
 - gamma-ray bright - two outbursts on 2013/2015 No radio counter parts - gamma-ray downstream the jet - radio counterparts under a variability - variation of Doppler boosting - actually no radio counter part (a sad orphan flare) A sad orphan flare might occur due to inverse Compton scattering by seed photons from e.g., a jet sheath (ring of fire model) 


  15. Highlight 3. A Gamma-ray Flare offset from the Radio Emitting Regions Algaba et al. 2018, ApJ We observed 1633+382 - 2012 Mar - 2015 Aug 
 - a radio loud AGN (< 5 Jy) 
 - gamma-ray bright - five outbursts correlated with multi-band Cross correlation - flux at different bands are significantly correlated - gamma-ray leads radio by about 70 days (i.e., 40 pc) - gamma-ray flare offset from radio emitting regions by 40 pc Algaba+ submitted A happy correlated flare might occur in the inner regions of the jet, due to a shock propagating a radio emitting regions.

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