A Candidate Recoiling SMBH in a Local Active Galaxy?

ORAL

Abstract

Merging Supermassive Black Holes are a predicted key feature of models describing the co-evolution of galaxies and Active Galactic Nuclei (AGN). Following the merger, the SMBH is expected to undergo gravitational recoil velocities on the order of hundreds to thousands of km/s due to the anisotropic emission of gravitational radiation. Given that the majority of (massive) galaxies are thought to host a SMBH in the center, such events are expected to be relatively common. However, there have been only few candidates with no secure case so far. We present preliminary results of a recoiling SMBH candidate, discovered in a spectroscopic study of local AGNs selected from the SDSS. The SDSS image shows a blue knot offset from the center of the host galaxy by 1.5 arcsec, and SDSS fiber-spectra show asymmetric broad emission lines. Keck spectra centered on the host galaxy do not show broad lines; follow-up Lick spectroscopy associates AGN emission with the location of the blue knot. While these features are expected for a SMBH undergoing recoil, we discuss other possibilities such as a type IIn supernova or an ongoing merger.

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Authors

  • Bryan Scott

    California Polytechnic State University, San Luis Obispo

  • Vardha Bennert

    California Polytechnic State University, San Luis Obispo

  • Sergey Savrasov

    Hartnell College, Cal State Univ- Long Beach, University of California, Davis, School of Natural Science, University of California, Merced, Seagate Technology, Materials Science and Engineering, National Tsing Hua University, Taiwan, University of California - Berkeley, University of Colorado, Boulder -- Dept of Physics, University of California, Berkeley -- Dept of Chemistry, UC Merced, California State University, Fresno, California Institute of Technology, California State University, Long Beach, La Canada Flintridge, CA, Department of Physics, Florida A\&M University, Tallahassee, FL-32307, Physical and Life Sciences, Lawrence Livermore National Laboratory, Livermore, CA-94550, Cal State Univ East Bay, American River College, UC Santa Cruz, Notre Dame High School, Benedict College, Lawrence Livermore National Laboratory, Tuskegee University, California State University, Dominguez Hills, Sonoma State University, Carnegie Observatories, University of California, Los Angeles, Institute of Astronomy, University of Cambridge, UK, University of California, Santa Barbara, University of Alabama, MPIfR, Bonn, Germany, Stanford University, University of California - Davis

  • Sergey Savrasov

    Hartnell College, Cal State Univ- Long Beach, University of California, Davis, School of Natural Science, University of California, Merced, Seagate Technology, Materials Science and Engineering, National Tsing Hua University, Taiwan, University of California - Berkeley, University of Colorado, Boulder -- Dept of Physics, University of California, Berkeley -- Dept of Chemistry, UC Merced, California State University, Fresno, California Institute of Technology, California State University, Long Beach, La Canada Flintridge, CA, Department of Physics, Florida A\&M University, Tallahassee, FL-32307, Physical and Life Sciences, Lawrence Livermore National Laboratory, Livermore, CA-94550, Cal State Univ East Bay, American River College, UC Santa Cruz, Notre Dame High School, Benedict College, Lawrence Livermore National Laboratory, Tuskegee University, California State University, Dominguez Hills, Sonoma State University, Carnegie Observatories, University of California, Los Angeles, Institute of Astronomy, University of Cambridge, UK, University of California, Santa Barbara, University of Alabama, MPIfR, Bonn, Germany, Stanford University, University of California - Davis

  • Sergey Savrasov

    Hartnell College, Cal State Univ- Long Beach, University of California, Davis, School of Natural Science, University of California, Merced, Seagate Technology, Materials Science and Engineering, National Tsing Hua University, Taiwan, University of California - Berkeley, University of Colorado, Boulder -- Dept of Physics, University of California, Berkeley -- Dept of Chemistry, UC Merced, California State University, Fresno, California Institute of Technology, California State University, Long Beach, La Canada Flintridge, CA, Department of Physics, Florida A\&M University, Tallahassee, FL-32307, Physical and Life Sciences, Lawrence Livermore National Laboratory, Livermore, CA-94550, Cal State Univ East Bay, American River College, UC Santa Cruz, Notre Dame High School, Benedict College, Lawrence Livermore National Laboratory, Tuskegee University, California State University, Dominguez Hills, Sonoma State University, Carnegie Observatories, University of California, Los Angeles, Institute of Astronomy, University of Cambridge, UK, University of California, Santa Barbara, University of Alabama, MPIfR, Bonn, Germany, Stanford University, University of California - Davis

  • Sergey Savrasov

    Hartnell College, Cal State Univ- Long Beach, University of California, Davis, School of Natural Science, University of California, Merced, Seagate Technology, Materials Science and Engineering, National Tsing Hua University, Taiwan, University of California - Berkeley, University of Colorado, Boulder -- Dept of Physics, University of California, Berkeley -- Dept of Chemistry, UC Merced, California State University, Fresno, California Institute of Technology, California State University, Long Beach, La Canada Flintridge, CA, Department of Physics, Florida A\&M University, Tallahassee, FL-32307, Physical and Life Sciences, Lawrence Livermore National Laboratory, Livermore, CA-94550, Cal State Univ East Bay, American River College, UC Santa Cruz, Notre Dame High School, Benedict College, Lawrence Livermore National Laboratory, Tuskegee University, California State University, Dominguez Hills, Sonoma State University, Carnegie Observatories, University of California, Los Angeles, Institute of Astronomy, University of Cambridge, UK, University of California, Santa Barbara, University of Alabama, MPIfR, Bonn, Germany, Stanford University, University of California - Davis

  • Sergey Savrasov

    Hartnell College, Cal State Univ- Long Beach, University of California, Davis, School of Natural Science, University of California, Merced, Seagate Technology, Materials Science and Engineering, National Tsing Hua University, Taiwan, University of California - Berkeley, University of Colorado, Boulder -- Dept of Physics, University of California, Berkeley -- Dept of Chemistry, UC Merced, California State University, Fresno, California Institute of Technology, California State University, Long Beach, La Canada Flintridge, CA, Department of Physics, Florida A\&M University, Tallahassee, FL-32307, Physical and Life Sciences, Lawrence Livermore National Laboratory, Livermore, CA-94550, Cal State Univ East Bay, American River College, UC Santa Cruz, Notre Dame High School, Benedict College, Lawrence Livermore National Laboratory, Tuskegee University, California State University, Dominguez Hills, Sonoma State University, Carnegie Observatories, University of California, Los Angeles, Institute of Astronomy, University of Cambridge, UK, University of California, Santa Barbara, University of Alabama, MPIfR, Bonn, Germany, Stanford University, University of California - Davis

  • Sergey Savrasov

    Hartnell College, Cal State Univ- Long Beach, University of California, Davis, School of Natural Science, University of California, Merced, Seagate Technology, Materials Science and Engineering, National Tsing Hua University, Taiwan, University of California - Berkeley, University of Colorado, Boulder -- Dept of Physics, University of California, Berkeley -- Dept of Chemistry, UC Merced, California State University, Fresno, California Institute of Technology, California State University, Long Beach, La Canada Flintridge, CA, Department of Physics, Florida A\&M University, Tallahassee, FL-32307, Physical and Life Sciences, Lawrence Livermore National Laboratory, Livermore, CA-94550, Cal State Univ East Bay, American River College, UC Santa Cruz, Notre Dame High School, Benedict College, Lawrence Livermore National Laboratory, Tuskegee University, California State University, Dominguez Hills, Sonoma State University, Carnegie Observatories, University of California, Los Angeles, Institute of Astronomy, University of Cambridge, UK, University of California, Santa Barbara, University of Alabama, MPIfR, Bonn, Germany, Stanford University, University of California - Davis