The road map for Cloudy development

This page outlines the general directions in which the code is now being developed. Plasma simulations are a research field of their own. A conference, published as an ASP Conference volume 247, Spectroscopic Challenges of Photoionized Plasmas, Ferland & Savin, editors, my review article in 2003 Annual Reviews Astronomy & Astrophysics, 41, 517 (available  here), and the graduate text Osterbrock & Ferland Astrophysics of Gaseous Nebulae and Active Galactic Nuclei (the publisher's web site is  here) summarize the current state of plasma codes, the physics of ionized gas, and what needs to be done next.

The goal is to do a complete simulation of what happens in nature. The capabilities of the code have always been limited by available computer power. As machines grow more powerful it becomes possible to increase the physical fidelity of the simulation. The highest priority has been to include physics processes that affect the physical state of the gas - that is, its kinetic temperature, ionization, and chemical state, together with its observed spectrum.

C13 - new - newmole - the revised chemistry network

Robin Williams largely rewrote the chemistry solvers using a more modular approach. With further expansion the chemistry network, originally described in Abel et al. 2005ApJS..161...65A, could become an external database. It would then be simple to switch between different networks such as UMIST or Ohio. The network will be easier to maintain since it will be a matter of changing an entry in the database rather than a modification of the source code in several places.

The newmole branch has existed for several years and has been extensively tested. We believe this to be a more robust solver due to the design and features Robin built in. It should come onto the trunk soon and we expect it to be part of the 2013 release of Cloudy.

C13 - new - database driven atomic and molecular structure and emission

Up to now the structure and rates for models molecules, atoms, and ions were coded by hand. This makes expansion of these models, and updates to the rates, a difficult job. We are working to use the  Lambda and  Chianti databases to replace the models now in the code. This will increase the number of species with internal structure and observed spectra and will make the code and its data much easier to maintain.

The following lists directions in which Cloudy is now being developed.

time dependence


higher order dimensionality

radiative transfer methods

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