Abstract
From the analysis of the measurements of KM-type stars done in the near infrared (1 to 3.5 microns: the JHKL bands of Johnson's system), with a 83-cm reflector and a PbS detector at La Plata Observatory, we try to establish a new photometric classification system that discriminate luminosity class by means of certain parameters defined by infrared colours and infrared magnitudes. Data compiled and homogeneized by J. Koornneef of southern bright stars in those bands were also included. The results give us information about the spectral types and reddening of those stars. We also indicate how to calculate the radiation excess that those stars could have.
