On the spectra and photometry of M-giant stars

From a sample of 97 very bright M-giant stars in the Solar neighbourhood, high-quality intrinsic spectra in the spectral range 380≤λ[nm]≤900 for all M-spectral subtypes of the Case and MK classification systems are obtained. The results are fitted to photospheric synthetic spectra in the range 99≤λ[nm]≤12500 in order to infer the corresponding continua. The synthetic spectra are also compared to the intrinsic spectra. The effective temperatures are derived and mathematical spectral classification criteria are found. The (UB) j (VRI) c (JHKLM) ESO photometric data of the sample are also given. The data are available on the Strasbourg Astronomical Data Centre (CDS)