https://github.com/hongwanliu/DarkHistory

DarkHistory

arXiv

DarkHistory is a Python code package that calculates the global temperature and ionization history of the universe given an exotic source of energy injection, such as dark matter annihilation or decay. DarkHistory is described in a paper available at arXiv:1904.09296. Please cite this paper if you use DarkHistory in a scientific publication. For detailed information, please visit our readthedocs webpage here.

Installation

Updated 2025/06/16

• Clone this repository and checkout the branch you wish to use. The currently active branches are: master, lowengelec_upgrade, and early_halo_cooling.
• Create a new virtual environment for DarkHistory (recommended). For example, using conda:

conda create -n darkhistory python=3.12 pip
conda activate darkhistory

• Install the package via pip in the DarkHistory/ directory

pip install .

• Download the data files required to run DarkHistory and save them to a preferred location.
• Inform DarkHistory of the data files' location by either:
  • Setting the environment variable DH_DATA_DIR to the directory containing data files,
  • Setting the variable data_path_default in darkhistory/config.py directly.

DarkHistory is now ready to use. You can test your installation with the example code below. Additionally, familiarize yourself with DarkHistory by exploring the notebooks in the examples/ directory.

Recent updates

• 2025/06/16: Fixed installation. Update scipy compatibility (1.15.3).
• 2025/02/23: Custom injection now passes tracked state (Tm, xHII, xHeII, photon spectrum) to injection function.
• 2024/10/14: Downgraded float128 arrays to float64 in code and dataset. This does not result in changes beyond machine precision.