Feeding the Black-Holes: From Cooling Filaments to H2 Accretion Disks

JWST’s observations will detect a range of molecular hydrogen emission lines from molecular filaments that are part of the cooling flow phenomenon. Ferland’s will develop and apply a new grid of spectral emission templates that will make it possible to understand the observations on a physical basis and will be made openly available. A 2007 – 2011 series of papers (2007MNRAS.382.1246J, 2008MNRAS.386L..72F, 2009MNRAS.392.1475F, 2010A&A...518L..46E, 2011MNRAS.411..411C, 2011MNRAS.417..172F, 2011MNRAS.417.3080C) resulted from Ferland’s last major effort to understand molecular hydrogen emission in clusters. These used the best available molecular data and were possible because of the continuous development of the Cloudy spectral synthesis code. Cloudy is openly available and a NASA ADS cross-search shows that 111 JWST investigations cited Cloudy in 2023. This project will advance and apply Cloudy to JWST observations and make it possible for many others to do similar calculations. Much has changed in the dozen years since the 2010 series of papers. The advances that are needed and will be made possible by our work include the following: • The greatest change, and the greatest uncertainty, involves collisions exciting molecular hydrogen. These have a direct effect on the observed intensities of the JWST lines. Molecular data papers appear scattered across the astronomy, physics, and chemistry literature and some diligence is required to find them. The literature survey and conversation of published basic data into a format that can be used by Cloudy’s solvers will take two weeks. • Grids of non-equilibrium molecular spectral templates will be generated using Cloudy. These include a full simulation of the chemical and thermal state of the gas. A range of densities, grain abundances (very important because grains mediate the chemistry) and energy sources will be adopted. These grids will be made publicly available. This effort will require one week. • Cloudy development is driven by observational challenges. The effort will be spread over two years so that reduced JWST spectra will be available as the spectral grids are derived. • Both the spectral grids and an improved version of Cloudy will be publicly available. The Cloudy project has an open GitLab repository at wiki.nublado.org. All products of our work will be posted here. These last two steps will complete the remaining effort.