In the light of the preceding chapter, we know that there is a correlation between the form of the lightcurve and its luminosity to the maximum. We saw that the supernovæ with the rates of luminous decrease after the maximum of luminosity slowest, were also most luminous. In the continuation, we will detail how starting from this correlation it is possible to correct the luminosity of the supernovæ to the maximum to reduce dispersion to approximately 15%.
A second effect can bias in a significant way measurement of the luminosity of the supernovæ: the extinction by dust directly in the galaxy host or by intergalactic dust. We will detail how it is possible, starting from measurement of color, to make an estimate of this extinction.
Correlation factor of etirement/luminosity to the maximum