CERIDWEN Stellar Population Grids: Standard SSPs, BPASS, and Alpha Enhancement

Stellar population synthesis grids ssp_data_mist_miles.h5 FSPS v3.2 grid generated with python-fsps v0.4.7 using MIST isochrones, MILES spectra, and a Chabrier (2003) IMF. Property Value Isochrones MIST Spectral library MILES IMF Chabrier (2003), imf_type = 1 FSPS version 0.5.0 Schema version 1.0 Build arguments {'imf_type': 1} Metallicity grid 13 points in log10(Z), spanning [-4.233, -1.233] Age grid 107 points in log10(age/Gyr), spanning [-4.000, +1.300] Age range 0.0001-20 Gyr Wavelength grid 5,994 points spanning 91-100,000,000 Angstrom Flux-array shape (13, 107, 5994) Axis order (n_met, n_age, n_wave) Flux units L_sun Hz^-1 M_sun^-1 Data type float64 Approximate size 63.6 MB The metallicity values represent the absolute metallicity mass fraction, Z, rather than Z/Z_sun. ssp_data_bpass.h5 Grid generated from the pre-integrated BPASS v2.x simple stellar population models. The IMF and binary stellar-evolution assumptions are fixed by the BPASS SSP tables. Property Value Isochrone type bpss Spectral library bpass Recorded FSPS parameters {'imf_type': 1} FSPS version 0.4.9.dev16+gc18b87021 Schema version 1.0 Metallicity grid 12 points in log10(Z), spanning [-4.000, -1.398] Age grid 43 points in log10(age/Gyr), spanning [-3.000, +1.200] Age range 0.001-15.8 Gyr Wavelength grid 15,000 points spanning 1-100,000,000 Angstrom Flux-array shape (12, 43, 15000) Axis order (n_met, n_age, n_wave) Flux units L_sun Hz^-1 M_sun^-1 Data type float64 Approximate size 59.1 MB The metallicity values represent the absolute metallicity mass fraction, Z, rather than Z/Z_sun. amist_c3k_lr_chab_afe.h5 FSPS grid generated using MIST isochrones, the low-resolution C3K spectral library, and a Chabrier-type IMF. The grid includes an additional alpha-enhancement dimension. Property Value Isochrones MIST Spectral library c3k_lr IMF imf_type = 1 FSPS version 0.4.9.dev16+gc18b87021 Schema version 2.0 Build arguments {'imf_type': 1} Alpha-enhancement grid 5 points: [-0.2, 0.0, 0.2, 0.4, 0.6] Metallicity grid 13 points in log10(Z), spanning [-4.233, -1.233] Age grid 107 points in log10(age/Gyr), spanning [-4.000, +1.300] Age range 0.0001-20 Gyr Wavelength grid 1,936 points spanning 100.0-99,595,854.9 Angstrom Flux-array shape (5, 13, 107, 1936) Axis order (n_afe, n_met, n_age, n_wave) Flux units L_sun Hz^-1 M_sun^-1 Data type float64 Approximate size 102.7 MB Here, Z is the absolute total metallicity mass fraction. It is neither Z/Z_sun nor [Fe/H]. ssp_data_mist_c3k_lr.h5 FSPS grid generated using MIST isochrones, the low-resolution C3K spectral library, and a Chabrier-type IMF. Property Value Isochrones MIST Spectral library c3k_lr IMF imf_type = 1 FSPS version 0.5.0 Schema version 1.0 Build arguments {'imf_type': 1} Recorded wavelength limits 100.0-99,595,854.9 Angstrom Metallicity grid 13 points in log10(Z), spanning [-4.233, -1.233] Age grid 107 points in log10(age/Gyr), spanning [-4.000, +1.300] Age range 0.0001-20 Gyr Wavelength grid 1,936 points spanning 100.0-99,595,854.9 Angstrom Flux-array shape (13, 107, 1936) Axis order (n_met, n_age, n_wave) Flux units L_sun Hz^-1 M_sun^-1 Data type float64 Approximate size 20.5 MB The metallicity values represent the absolute metallicity mass fraction, Z, rather than Z/Z_sun.