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Y. Gotberg, 27 June 2023

This zenodo directory contains the spectral fitting function used in 
the manuscript "Stellar properties of observed stars stripped in binaries 
in the Magellanic Clouds" by Gotberg, Drout, Ji, Groh, Ludwig, Crowther, 
Smith, de Koter & de Mink. The directory contains the following files:

o S41_compressed_grid.tar.gz
o spectral_fitting_routine.tar.gz 

Both of the above .tar.gz files contain a collection of files, which we 
describe in more derail below. 

# # # S41_compressed_grid.tar.gz # # # 
When inflated, this .tar.gz contains a compressed version of the 
spectral model grid presented in the manuscript (see section 4.1). Each 
model folder contains a set of pieces of the normalized spectrum that
each corresponds to a spectral line (e.g. line_HeII4686.txt), the full 
spectral energy distribution and the normalized spectra (SED.txt), 
absolute magnitudes of each model assuming a sequence of extinctions (AV) 
and following average extinction curves of the LMC, SMC, and Milky Way 
from Gordon and collaborators (labeled absolute_AB_magnitudes_LMC.txt, 
absolute_AB_magnitudes_SMC.txt, and absolute_AB_magnitudes_MW.txt) and 
the CMFGEN file MOD_SUM, which contains various useful information about 
the model properties. The model folders are each labeled according to the 
surface gravity, temperature and surface hydrogen mass fraction (e.g. 
logg5.5_T140000.0_H01 has log g=5.5, T=140 kK, and X_H,surface = 0.1). 

The full CMFGEN models are available in the zenodo repository with DOI: 
10.5281/zenodo.7976200
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# # # spectral_fitting_routine.tar.gz # # # 
When inflated this .tar.gz contains the following: 
o fitting_routine.py (main fitting routine)
o input_fit.txt (input file)
o reflat_pieces.txt 
o functions (contains the functions adjust_errors.py, chi2.py, 
  constants.py, estimate_vobs.py, extrapolate.py, smear.py, vacuum_air.py)
o filters (folder containing filter transmission functions and zeropoints)
o data (LMC_final_combined_photom.csv, SMC_final_combined_photom.csv, 
  evolutionary_grid_002.txt, evolutionary_grid_006.txt)

# fitting_routine.py 
This is the file to run for running the fitting routine. 

# input_fit.txt 
This is the input file - fill it out to adjust what to fit. We provide the
M-L relations in the data folder (evolutionary_grid_002/6.txt) and the photometry
of the 10 stars we analyze in the manuscript in the data folder 
(S/LMC_final_combined_photom.csv). For testing purposes, we have also added 
the spectrum for Star 6 (star6.txt) in the data folder, which also is available
in the zenodo directory with DOI: 10.5281/zenodo.8075920. 

# functions 
This folder contains a set of functions that are used in fitting_routine.py. 
o chi2.py contains chi2 minimizations used on the input spectral lines
o estimate_vobs.py is used for inferring a velocity shift of the data compared 
  to the models.
o smear.py adjusts the models to the spectral resolution set by the parameter R.
  The default value is adjusted to MagE spectra.
o vacuum_air.py contains functions that converts wavelengths between vacuum and air. 
o adjust_errors.py makes a rough estimate for errors in observed spectra based
  on fluctuations of the continuum (connected to the wavelength ranges set by 
  the input quantity lambda_ranges_error_estimate). 
o constants.py contains a few constants. 
o extrapolate.py is only used for extrapolating the evolutionary mass beyond the 
  edges of the M-L relation modeled data.