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Tracing the Milky Ways Vestigial Nuclear Jet

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 Added by Gerald Cecil
 Publication date 2021
  fields Physics
and research's language is English




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MeerKAT radio continuum and XMM-Newton X-ray images have recently revealed a spectacular bipolar channel at the Galactic Center that spans several degrees ($sim$0.5 kpc). An intermittent jet likely formed this channel and is consistent with earlier evidence of a sustained, Seyfert-level outburst fueled by black-hole accretion onto SgA* several Myr ago. Therefore, to trace an intermittent jet that perhaps penetrated, deflected, and percolated along multiple paths through the interstellar medium, relevant interactions are identified and quantified in archival X-ray images, Hubble Space Telescope Paschen-$alpha$ images and ALMA mm-wave spectra, and new SOAR telescope IR spectra. Hydrodynamical simulations are used to show how a currently weak jet can explain these structures and inflate the ROSAT/eROSITA X-ray and Fermi $gamma$-ray bubbles that extend $pm$60 deg from the Galactic plane. Thus, our Galactic outflow has features in common with energetic, jet-driven structures in the prototypical Seyfert galaxy NGC 1068.



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