The central regions of active galaxies are known to contain clumpy gas including supersonic clouds. Fast moving clouds are also observed in galactic winds. Clouds are in fact central components of…

This is a research grant award from the National Aeronautics and Space Administration (NASA) to the Board of Regents of the Nevada System of Higher Education, doing business as the University of Nevada, Las Vegas (UNLV). The $461,194.14 grant will support a project to develop a comprehensive and quantitative theory for the formation, destruction, and acceleration of clumpy gas clouds in the central regions of active galaxies. The research aims to better understand the radiation-hydrodynamics and -magnetodynamics of these clouds through high-resolution three-dimensional simulations, which will produce observational diagnostics to be compared with data from current and future NASA missions. This grant does not have a set-aside designation. The Nevada System of Higher Education, through its Sponsored Programs Office, serves as the parent organization overseeing UNLV's federal research contracts and grants.

The central regions of active galaxies are known to contain clumpy gas including supersonic clouds. Fast moving clouds are also observed in galactic winds. Clouds are in fact central components of unification models for active galactic nuclei (AGN) and form the basis of many photoionization and dynamical modelling efforts. However, despite many years of intensive studies, the origin and dynamics of clouds remain uncertain, mostly because multi-dimensional geometrical effects and the radiation-hydrodynamics and -magnetodynamics are poorly understood. We propose to continue our quest to develop a comprehensive and quantitative theory for cloud formation, destruction, and acceleration based on high resolution local simulations. Our earlier simulations showed, from first principles, that thermal instability and radiation pressure can facilitate the formation, regeneration and acceleration of clouds. However, these simulations did not capture some important physical and geometrical aspects of clouds as they were one- and two-dimensional and neglected magnetic fields. Here we propose to make three natural, yet transformative extensions of our earlier work: 1) add magnetic fields and anisotropic conduction; 2) carry out the simulations in three-dimensions; and 3) compute many observational diagnostics such as profiles of the optical, UV, and x-RAY lines, emission line ratios, and broad-band continuum spectra. The results of this project will reveal the basic physical properties of flows in AGN with unprecedented accuracy and detail. The observational diagnostics will be compared with observations by both current NASA missions such as HST, chandra, spitzer, swift, and nustar as well as future missions such as jwst.