Classifying Algols A and C Using Low-Resolution Spectra

We present multi-epoch low-resolution optical spectra (3850 - 4950 Angstroms) of the Algol triple system which exhibit spectroscopic variability as a function of the close binary’s orbital phase. It is possible to identify spectral signatures associated with the two brightest components, Algols A and C, so we developed an algebraic method to disentangle Algol C’s contribution to the spectrum. This allows us to assign Algol C with a spectral type. Since spectral disentanglement is generally only performed on high-resolution spectra, where techniques can be used to separate lines based on their relative Doppler shifts as a function of orbital phase, this technique may be of interest to others with access to low-resolution spectra, particularly to those who are performing stellar spectral classification on spectroscopic binaries.