Dust in the Wind: insights into the supermassive black hole - galaxy connection with the James Webb Space Telescope

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Active Galactic Nuclei (AGN) are the powerhouses of the Cosmos. They are the sites where supermassive black holes, lurking in the hearts of galaxies, generate enormous amounts of energy as they draw material from interstellar space into their deep gravitational wells. Some of this energy is liberated in the form of fast outflows or winds of matter that can travel thousands of light years away from the AGN, taking with them the capacity to heat up and expel gas from the galaxy at large, forever affecting its future evolution. A thorough understanding of the physics of such outflows is an important part of our modern picture of the fate of galaxies and matter in the Universe.The James Webb Space Telescope (JWST) is the greatest and most-awaited advance of this decade in astronomy. Through a highly competitive selection process, we have obtained unprecedented observations of 11 well-known and well-studied nearby AGN, which consist of a gallery of images across the mid-infared bands of the electromagnetic spectrum, and, for a subset of 6 targets, a set of three-dimensional spectroscopic cubes spanning the same wavelengths. With this exceptional dataset, our study will examine the evidence for winds of dusty gas heated and accelerated by AGN out into their host galaxies. We will be able to identify the tell-tale structural signatures of dusty winds, such their biconical form seen at right angles to the discs of gas that feed the central black holes. We will be able to determine the composition and dust properties of the winds, and measure their masses and heat content.Our work is part of a major international research enterprise called the Galaxy Activity, Torus and Outflow Survey (GATOS). Over the years, GATOS has obtained some spectacular data for all the AGN in our programme, including images from the Hubble Space Telescope, and maps of molecular gas from the Atacama Large Millimeter/sub-millimeter Array (ALMA). Using these, we will explore how these AGN influence the gaseous environment of their galaxy centres. We will determine the ways that energy is transferred between different components of the interstellar gas as it rises out of the nucleus and dissipates into the wider galaxy. This has the potential to revolutionise our understanding of the feedback loop that connects gas, galaxies, and supermassive black holes.