University of Hertfordshire

From the same journal

From the same journal

By the same authors

Violent quenching: Molecular Gas Blown to 1000 km s -1 during a Major Merger

Research output: Contribution to journalArticle


  • 1807.09789

    Accepted author manuscript, 2.65 MB, PDF document

  • J. E. Geach
  • C. Tremonti
  • A. M. Diamond-Stanic
  • P. H. Sell
  • A. A. Kepley
  • A. L. Coil
  • G. Rudnick
  • R. C. Hickox
  • J. Moustakas
  • Yujin Yang
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Original languageEnglish
Article numberL1
Pages (from-to)1
Number of pages5
JournalAstrophysical Journal Letters
Publication statusPublished - 23 Aug 2018


We present Atacama Large Millimeter/submillimeter Array observations of a massive () compact ( pc) merger remnant at z = 0.66 that is driving a 1000 km s -1 outflow of cool gas, with no observational trace of an active galactic nucleus (AGN). We resolve molecular gas on scales of approximately 1-2 kpc, and our main finding is the discovery of a wing of blueshifted CO J(2 → 1) emission out to-1000 km s -1 relative to the stars. We argue that this is the molecular component of a multiphase outflow, expelled from the central starburst within the past 5 Myr through stellar feedback, although we cannot rule out previous AGN activity as a launching mechanism. If the latter is true, then this is an example of a relic multiphase AGN outflow. We estimate a molecular mass outflow rate of approximately 300 M o yr -1, or about one third of the 10 Myr-Averaged star formation rate. This system epitomizes the multiphase "blowout" episode following a dissipational major merger-a process that has violently quenched central star formation and supermassive black hole growth.


Accepted for publication in ApJ Letters

ID: 15274119