Related papers: The 2017 Release of Cloudy
We present the 2025 release of the spectral synthesis code Cloudy, highlighting significant enhancements to the scope and accuracy of the physics which have been made since the previous release. A major part of this development involves…
We describe the 2023 release of the spectral synthesis code Cloudy. Since the previous major release, migrations of our online services motivated us to adopt git as our version control system. This change alone led us to adopt an annual…
This is a summary of the 2013 release of the plasma simulation code Cloudy. Cloudy models the ionization, chemical, and thermal state of material that may be exposed to an external radiation field or other source of heating, and predicts…
The gas that is present in the interstellar medium is usually very far removed from (local) thermodynamic equilibrium, and in some cases may also not be in a steady-state equilibrium with its surroundings. The physics of this material is…
We describe a new atomic and molecular database we developed for use in the spectral synthesis code Cloudy. The design of Stout is driven by the data needs of Cloudy, which simulates molecular, atomic, and ionized gas with kinetic…
X-ray missions with microcalorimeter technology will resolve spectral features with unprecedented detail. In this work, we improve the H-like K$\alpha$ energies for elements between 6 $\leq Z \leq$ 30 for the release version of the spectral…
We announce the C23.01 update of Cloudy. This corrects a simple coding error, present since $\sim$ 1990, in one routine that required a conversion from the line-center to the mean normalization of the Ly$\alpha$ optical depth. This affects…
The upcoming X-ray missions based on the microcalorimeter technology require exquisite precision in spectral simulation codes in order to match the unprecedented spectral resolution. In this work, we improve the fluorescence K$\alpha$…
We developed a new quick pseudo-3D photoionization code based on Cloudy (G. Ferland) and IDL (RSI) tools. The code is running the 1D photoionization code Cloudy various times, changing at each run the input parameters (e.g. inner radius,…
Here we present our current updates of the gas-phase chemical reaction rates and molecular lines in the spectral synthesis code CLOUDY, and its implications in spectroscopic modelling of various astrophysical environments. We include energy…
We discuss new functionality of the spectral simulation code CLOUDY which allows the user to calculate grids with one or more initial parameters varied and formats the predicted spectra in the standard FITS format. These files can then be…
With the launch of the XRISM microcalorimeter mission, space-based X-ray observations will achieve a record spectral resolving power of $R\equiv E/\Delta E\sim$1200. With this resolving power, emission features associated with…
We use the spectral synthesis code Cloudy to tabulate the properties of gas for an extensive range in redshift (z=0 to 9), temperature (log T [K] = 1 to 9.5), metallicity (log Z/$\mathrm{Z}_{\odot}$ = -4 to +0.5, Z=0), and density (log…
Absorption-line spectroscopy is a powerful tool used to estimate element abundances in the nearby as well as distant universe. The accuracy of the abundances thus derived is, naturally, limited by the accuracy of the atomic data assumed for…
We present a simple, yet powerful column density diagnostic for plasmas enabled by X-ray microcalorimeter observations. With the recent developments of the spectral simulation code Cloudy, inspired by the high spectral resolution of the…
The COS Legacy Archive Spectroscopic SurveY (CLASSY) is designed to provide the community with a spectral atlas of 45 nearby star-forming galaxies which were chosen to cover similar properties as those seen at high-z (z>6). The prime high…
The James Webb Space Telescope has ushered in an era of abundant high-redshift observations of young stellar populations characterized by strong emission lines, motivating us to integrate nebular emission into the new Maraston stellar…
This paper describes the most important differences between Cloudy 90 and Cloudy 94, the most recent upgrade of the code which has now been posted on the WWW. It also describes the upgrade of the grain model in Cloudy which is currently…
High precision atomic data is indispensable for experiments involving studies of fundamental interactions, astrophysics, atomic clocks, plasma science, and others. We develop new parallel atomic structure codes and explore the difficulties…
Atomic and molecular data are required to conduct detailed calculations of microphysical processes performed by CLOUDY to predict the spectra of a theoretical model. One of the three databases CLOUDY currently utilizes is CHIANTI version…