first_spec_class second_spec_class prob_first_spec_class prob_second_spec_class taxonomy wavelength author ref method S D 0.508000 0.237000 Bus-DeMeo VIS Erasmus 2018ApJS..237...19E PHOT S D 0.510000 0.227000 Bus-DeMeo VIS Erasmus 2019ApJS..242...15E PHOT