6.3.4. Combo Correlation

The correlation represents the combination of the Amati correlation and the *E* X iso–*E*iso– *E*<sup>p</sup> correlation and, like the Amati correlation, it holds for LGRBs only [140]. It relates the prompt emission *E*<sup>p</sup> and the X-ray afterglow luminosity *L*<sup>0</sup> and rest-frame duration *τ* of the plateau phase, and the late power-law decay index *α*, i.e., *L*<sup>0</sup> ∝ *E* 0.90 <sup>p</sup> *τ* −1 |1 + *α*|. The main drawback is that it is much more complicated than other correlations, as it depends upon four parameters. For details, see Ref. [141].
