This is the coefficent $N_0$ used for calculating cable partial transient temperature rise acc. to IEC 60853-2.

Symbol
$N_{\mathrm{0}}$
Unit
Formulae
$Q_{\mathrm{A}} Q_{\mathrm{B}} T_{\mathrm{A}} T_{\mathrm{B}}$
Related
$Q_{\mathrm{A}}$