A NIR spectral sequence of O-type supergiants

GIUDICI MICHILINI, F.; MORRELL, N I; FERRERO, G; BARBÁ, R H; GAMEN, R. C.

Rosario

Congreso; Reunión Anual de la AAA; 2020

AAA

The study of spectral morphology is a powerful tool for understanding the fundamental properties of stars. The spectral classification scheme for O stars was revisited and a new set of spectral standard stars was proposed for all sub-types between O2 and B0 and for all luminosity classes. We are working on the construction of a spectral atlas with high quality observations between 0.85-2.5 μ m. Observations for this project have begun seven years ago, and they are carried out with the GNIRS (Gemini Observatory) and FIRE (Las Campanas Observatory) spectrographs. We present here a second batch of results, including the spectra of a complete temperature sequence of supergiant standard stars in the J, H and K-bands. The analysis of this data set implies that {it} is possible to define spectral classification criteria using the He I and He II lines present in it.