Quantitative spectral classification

Table 4 contains the averaged values of the classification criteria (indices) for 54 stars used in our analysis. Each measurement in our analysis refers to an area confined by the border wavelengths for an interval, the spectral energy distribution and the zero level.

We chose the intervals for measurements in a such way that the sensitivity to spectral and/or luminosity effects were different for two adjacent or near-by intervals. The ratios of measurements in such intervals may then serve as classification criteria (indices) with minimum contamination by interstellar extinction. Table 2 contains the border wavelengths for the intervals with indications of the principal measured features.