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Integral Field Spectroscopy of Massive, Kiloparsec-Scale Outflows in the Infrared-Luminous QSO Mrk 231

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 نشر من قبل David S. N. Rupke
 تاريخ النشر 2011
  مجال البحث فيزياء
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 تأليف David S. N. Rupke




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The quasi-stellar object (QSO)/merger Mrk 231 is arguably the nearest and best laboratory for studying QSO feedback. It hosts several outflows, including broad-line winds, radio jets, and a poorly-understood kpc scale outflow. In this Letter, we present integral field spectroscopy from the Gemini telescope that represents the first unambiguous detection of a wide-angle, kpc scale outflow from a powerful QSO. Using neutral gas absorption, we show that the nuclear region hosts an outflow with blueshifted velocities reaching 1100 km/s, extending 2-3 kpc from the nucleus in all directions in the plane of the sky. A radio jet impacts the outflow north of the nucleus, accelerating it to even higher velocities (up to 1400 km/s). Finally, 3.5 kpc south of the nucleus, star formation is simultaneously powering an outflow that reaches more modest velocities of only 570 km/s. Blueshifted ionized gas is also detected around the nucleus at lower velocities and smaller scales. The mass and energy flux from the outflow are >~2.5 times the star formation rate and >~0.7% of the active galactic nucleus luminosity, consistent with negative feedback models of QSOs.

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