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This is a fork from the original BADASS repo here.

Ridiculous acronyms are a long-running joke in astronomy, but here, spectral fitting ain't no joke!

BADASS is an open-source spectral analysis tool designed for detailed decomposition of Sloan Digital Sky Survey (SDSS) spectra, and specifically designed for the fitting of Type 1 ("broad line") Active Galactic Nuclei (AGN) in the optical. The fitting process utilizes the Bayesian affine-invariant Markov-Chain Monte Carlo sampler emcee for robust parameter and uncertainty estimation, as well as autocorrelation analysis to access parameter chain convergence. BADASS can fit the following spectral features:

• Stellar line-of-sight velocity distribution (LOSVD) using Penalized Pixel-Fitting (pPXF, Cappellari et al. (2017)) using templates from the Indo-U.S. Library of Coudé Feed Stellar Spectra (Valdes et al. (2004)) in the optical region 3460 Å - 9464 Å.
• Broad and Narrow FeII emission features using the FeII templates from Véron-Cetty et al. (2004) or Kovačević et al. (2010).
• UV iron template from Vestergaard and Wilkes (2001)
• Individual narrow, broad, and/or absorption line features.
• AGN power-law continuum and Balmer pseudo-continuum.
• "Blue-wing" outflow emission components found in narrow-line emission.

A more-detailed summary of BADASS, as well as a case-study of ionized gas outflows, is given in Sexton et al. (2021).

All spectral components can be turned off and on via the Jupyter Notebook interface, from which all fitting options can be easily changed to fit non-AGN-host galaxies (or even stars!). BADASS uses multiprocessing to fit multiple spectra simultaneously depending on your hardware configuration. The code was originally written in Python 2.7 to fit Keck Low-Resolution Imaging Spectrometer (LRIS) data (Sexton et al. (2019)), but because BADASS is open-source and not written in an expensive proprietary language, one can easily contribute to or modify the code to fit data from other instruments. Out of the box, BADASS fits SDSS spectra, MANGA IFU cube data, and examples are provided for fitting user-input spectra of any instrument.

Credits

• Dr. Remington Oliver Sexton (USNO/GMU)
• Sara Doan (GMU)
• Michael Reefe (GMU)
• William Matzko (GMU)

License

MIT License

Copyright (c) 2022 Remington Oliver Sexton

Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.