GPU Accelerated Absorption Simulation (GAAS)

A python based rapid and accurate broadband gas spectrum simulator that supports both Voigt and HTP based line shapes. Orders of magnitude faster than HAPI for spectra with more than 1000 absorption transitions. Based on a natively written OpenCL implementation of the complex error function which is derived from [http://ab-initio.mit.edu/wiki/index.php/Faddeeva_Package].

Installation

Clone the repo

git clone https://github.com/CharlieCallahan/GPU_Accelerated_Absorption_Sim.git

Install the requirements

python install.py

Quick Start

The repo comes with an example GUI to get you started. Run it with the following command:

python gaasGUI.py

Example

Additionally, the repo includes some example code to demonstrate how to run spectrum simulations using GAAS (example_voigt.py and example_htp.py).

Paper

Please cite us if you use this code in your research. doi: https://doi.org/10.1016/j.jqsrt.2024.109307

Charles S. Callahan, Sean M. Bresler, Sean C. Coburn, David A. Long, Gregory B. Rieker, GAAS: GPU accelerated absorption simulator, Journal of Quantitative Spectroscopy and Radiative Transfer, Volume 333, 2025, 109307, ISSN 0022-4073