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Probing Black Hole Accretion in Low Luminosity AGNs using ALMA Polarimetry

Research Project

Project/Area Number 15K17619
Research Category

Grant-in-Aid for Young Scientists (B)

Allocation TypeMulti-year Fund
Research Field Astronomy
Research InstitutionNational Astronomical Observatory of Japan

Principal Investigator

Nagai Hiroshi  国立天文台, アルマプロジェクト, 特任准教授 (00455198)

Research Collaborator Nakanishi Kouichiro  
Fujita Yutaka  
Asada Keiichi  
Project Period (FY) 2015-04-01 – 2019-03-31
Project Status Completed (Fiscal Year 2018)
Budget Amount *help
¥2,600,000 (Direct Cost: ¥2,000,000、Indirect Cost: ¥600,000)
Fiscal Year 2017: ¥650,000 (Direct Cost: ¥500,000、Indirect Cost: ¥150,000)
Fiscal Year 2016: ¥780,000 (Direct Cost: ¥600,000、Indirect Cost: ¥180,000)
Fiscal Year 2015: ¥1,170,000 (Direct Cost: ¥900,000、Indirect Cost: ¥270,000)
Keywords活動銀河核 / ブラックホール降着流 / ALMA / VLBI / アルマ望遠鏡 / 偏波観測 / ブラックホール質量降着流 / 電波観測 / アルマ / 超巨大ブラックホール / 質量降着現象 / ミリ波サブミリ波偏波観測
Outline of Final Research Achievements

Low-luminosity AGNs (LLAGNs) constitutes the largest population of AGNs in the nearby Universe, and thus the physical origin of those activities is quite important for the understanding of black hole accretion and its relation with the galaxy evolution in the present day of Universe. The polarization angle of the emission from AGNs is rotated as a passage through the accretion flow, so-called Faraday rotation effect. The measurement of Faraday rotation is a key method to constrain the accretion flow properties. We conducted ALMA and VLBI observations on the two nearby low luminosity AGNs. We found that the measured Faraday rotation is not consistent with the radiatively inefficient accretion flow (RIAF) model, which is the most favored model to explain the low luminosity. Alternatively, we propose that both RIAF and standard accretion disk co-exist or the accretion flow is highly inhomogeneous for these sources.

Academic Significance and Societal Importance of the Research Achievements

ブラックホールの重力エネルギーを起源として光り輝く活動銀河核は、天体毎の明るさに大きなばらつきが見られる。明るさのばらつきは、ブラックホール近傍における物質の降着の仕方に起因していると考えられる。我々の観測結果は、従来考えられてきた理論的な描像では説明が難しく、ブラックホールへ物質が落ちる過程は想像以上に複雑であることを示唆している。
先日、ブラックホールシャドウ撮影の成功が報告されたことにより、ますますブラックホールへの関心が高まりつつある。本科研費による研究成果ならびに今後の発展によって、ブラックホール周辺の物理についての理解がますます進むと考えられる。

Report

(5 results)
  • 2018 Annual Research Report   Final Research Report ( PDF )
  • 2017 Research-status Report
  • 2016 Research-status Report
  • 2015 Research-status Report
  • Research Products

    (21 results)

All 2018 2017 2016 2015 Other

All Int'l Joint Research (4 results) Journal Article (10 results) (of which Int'l Joint Research: 9 results,  Peer Reviewed: 10 results,  Open Access: 2 results,  Acknowledgement Compliant: 4 results) Presentation (7 results) (of which Int'l Joint Research: 5 results,  Invited: 1 results)

  • [Int'l Joint Research] INAF/Bologna University(イタリア)

    • Related Report
      2018 Annual Research Report
  • [Int'l Joint Research] ASIAA(Taiwan)

    • Related Report
      2016 Research-status Report
  • [Int'l Joint Research] ASIAA(台湾)

    • Related Report
      2015 Research-status Report
  • [Int'l Joint Research] The Istituto di Radioastronomia of INAF(イタリア)

    • Related Report
      2015 Research-status Report
  • [Journal Article] Revealing the Broad Line Region of NGC 1275: The Relationship to Jet Power2018

    • Author(s)
      Punsly Brian、Marziani Paola、Bennert Vardha N.、Nagai Hiroshi、Gurwell Mark A.
    • Journal Title

      The Astrophysical Journal

      Volume: 869 Issue: 2 Pages: 143-143

    • DOI

      10.3847/1538-4357/aaec75

    • Related Report
      2018 Annual Research Report
    • Peer Reviewed / Int'l Joint Research
  • [Journal Article] VERA monitoring of the radio jet 3C?84 in the period of 2007?2013: Detection of non-linear motion2018

    • Author(s)
      Hiura Koichiro、Nagai Hiroshi、Kino Motoki、Niinuma Kotaro、Sorai Kazuo、Chida Hikaru、Akiyama Kazunori、D’Ammando Filippo、Giovannini Gabriele、Giroletti Marcello、Hada Kazuhiro、Honma Mareki、Koyama Shoko、Orienti Monica、Orosz Gabor、Sawada-Satoh Satoko
    • Journal Title

      Publications of the Astronomical Society of Japan

      Volume: 70 Issue: 5

    • DOI

      10.1093/pasj/psy078

    • Related Report
      2018 Annual Research Report
    • Peer Reviewed / Int'l Joint Research
  • [Journal Article] Evidence of Jet?Clump Interaction: A Flip of the Radio Jet Head of 3C 842018

    • Author(s)
      Kino M.、Wajima K.、Kawakatu N.、Nagai H.、Orienti M.、Giovannini G.、Hada K.、Niinuma K.、Giroletti M.
    • Journal Title

      The Astrophysical Journal

      Volume: 864 Issue: 2 Pages: 118-118

    • DOI

      10.3847/1538-4357/aad6e3

    • Related Report
      2018 Annual Research Report
    • Peer Reviewed / Int'l Joint Research
  • [Journal Article] A wide and collimated radio jet in 3C84 on the scale of a few hundred gravitational radii2018

    • Author(s)
      Giovannini, G., 他計25名(M. Honma 14番目)
    • Journal Title

      Nature Astronomy

      Volume: in press Issue: 6 Pages: 472-477

    • DOI

      10.1038/s41550-018-0431-2

    • Related Report
      2018 Annual Research Report 2017 Research-status Report
    • Peer Reviewed / Open Access / Int'l Joint Research
  • [Journal Article] Enhanced Polarized Emission from the One-parsec-scale Hotspot of 3C 84 as a Result of the Interaction with the Clumpy Ambient Medium2017

    • Author(s)
      Nagai H.、Fujita Y.、Nakamura M.、Orienti M.、Kino M.、Asada K.、Giovannini G.
    • Journal Title

      The Astrophysical Journal

      Volume: 849 Issue: 1 Pages: 52-52

    • DOI

      10.3847/1538-4357/aa8e43

    • Related Report
      2017 Research-status Report
    • Peer Reviewed / Int'l Joint Research
  • [Journal Article] Discovery of a new subparsec counterjet in NGC 1275: the inclination angle and the environment2017

    • Author(s)
      Y. Fujita, & H. Nagai
    • Journal Title

      Monthly Notices of the Royal Astronomical Society, Letters

      Volume: 465 Issue: 1 Pages: L94-L98

    • DOI

      10.1093/mnrasl/slw217

    • Related Report
      2017 Research-status Report 2016 Research-status Report
    • Peer Reviewed / Acknowledgement Compliant
  • [Journal Article] ALMA Science Verification Data: Millimeter Continuum Polarimetry of the Bright Radio Quasar 3C 2862016

    • Author(s)
      Nagai, H., Nakanishi, K., Paladino, R., Hull, C. L. H., Cortes, P., Moellenbrock, G., Fomalont, E., Asada, K., Hada, K.
    • Journal Title

      The Astrophysical Journal

      Volume: 824 Issue: 2 Pages: 132-141

    • DOI

      10.3847/0004-637x/824/2/132

    • Related Report
      2016 Research-status Report
    • Peer Reviewed / Int'l Joint Research
  • [Journal Article] Submillimeter Polarization Observation of the Protoplanetary Disk around HD 1425272016

    • Author(s)
      Kataoka, A., Tsukagoshi, T., Momose, M., Nagai, H., Muto, T., Dullemond, C. P., Pohl, A., Fukagawa, M., Shibai, H., Hanawa, T., & Murakawa, K.
    • Journal Title

      The Astrophysical Journal Letters

      Volume: 831 Issue: 2 Pages: 6-12

    • DOI

      10.3847/2041-8205/831/2/l12

    • Related Report
      2016 Research-status Report
    • Peer Reviewed / Open Access / Int'l Joint Research / Acknowledgement Compliant
  • [Journal Article] Nature of radio feature formed by re-started jet activity in 3C 84 and its relation with γ-ray emissions2016

    • Author(s)
      Nagai, H., Chida, H., Kino, M., Orienti, M., D'Ammando, F., Giovannini, G., Hiura, K.
    • Journal Title

      Astronomische Nachrichten

      Volume: 337 Issue: 1-2 Pages: 69-72

    • DOI

      10.1002/asna.201512267

    • Related Report
      2015 Research-status Report
    • Peer Reviewed / Int'l Joint Research / Acknowledgement Compliant
  • [Journal Article] ALMA Science Verification Data: Millimeter Continuum Polarimetry of the Bright Radio Quasar 3C 2862016

    • Author(s)
      Nagai, H., Nakanishi, K., Paladino, R., Hull, C. L. H., Cortes, P., Moellenbrock, G., Fomalont, E., Asada, K., Hada, K.
    • Journal Title

      Astrophysical Journal

      Volume: 未定

    • Related Report
      2015 Research-status Report
    • Peer Reviewed / Int'l Joint Research / Acknowledgement Compliant
  • [Presentation] What does ALMA tell us about extragalactic magnetic field?2018

    • Author(s)
      Hiroshi Nagai
    • Organizer
      New Insights in Extragalactic Magnetic Fields, Focus Meeting 8 at the XXX IAU General
    • Related Report
      2018 Annual Research Report
    • Int'l Joint Research / Invited
  • [Presentation] Accretion Flow Property of 3C 84: A View Through Faraday Rotation2017

    • Author(s)
      Nagai, H.
    • Organizer
      Polarised Emission from Astrophysical Jets
    • Place of Presentation
      Ierapetra, Greece
    • Year and Date
      2017-06-12
    • Related Report
      2016 Research-status Report
    • Int'l Joint Research
  • [Presentation] ALMA Polarimetric Observations of Centaurus A2017

    • Author(s)
      Hiroshi Nagai
    • Organizer
      Submm/mm/cm QUESO Workshop 2017: Centimetre-Sub-Millimetre Q&U (and V) European Southern Observatory Workshop
    • Related Report
      2017 Research-status Report
    • Int'l Joint Research
  • [Presentation] ファラデー回転で探るNGC1275の核周環境2017

    • Author(s)
      永井 洋
    • Organizer
      2017年日本天文学会秋季年会
    • Related Report
      2017 Research-status Report
  • [Presentation] Accretion Flow Properties of NGC 12752017

    • Author(s)
      Hiroshi Nagai
    • Organizer
      Polarised Emission from Astrophysical Jets
    • Related Report
      2017 Research-status Report
    • Int'l Joint Research
  • [Presentation] アルマ偏波観測で探るCentaurus Aの質量降着流2016

    • Author(s)
      永井洋
    • Organizer
      2016年日本天文学会秋季年会
    • Place of Presentation
      愛媛大学(愛媛県、松山)
    • Year and Date
      2016-09-14
    • Related Report
      2016 Research-status Report
  • [Presentation] Long-term Radio and Gamma-ray Properties of 3C 842015

    • Author(s)
      永井 洋
    • Organizer
      5th Workshop on Compact Steep Spectrum and GHz-Peaked Spectrum Radio Sources
    • Place of Presentation
      Riccione, Italy
    • Year and Date
      2015-05-27
    • Related Report
      2015 Research-status Report
    • Int'l Joint Research

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Published: 2015-04-16   Modified: 2022-03-01  

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