The Luminosity/Spectral Lag Relations of the Short GRBs with Extended Emission

The Gamma-Ray Bursts (GRBs) are classified into the long GRBs (LGRBs) and the short GRBs (SGRBs). Their progenitors are expected to be different because they have its own distinct characteristics. Occasionally, the SGRBs having faint extended emission (EGRBs) are observed. The EGRBs exhibit the analogous properties that the SGRBs have, but observed T90 of the EGRBs is longer than two seconds as the LGRBs. Because the EGRBs have characteristics of the LGRBs and the SGRBs, study of the EGRBs is important to understand origins of the GRBs. In this study, we obtain the luminosity relations of the EGRBs observed by Swift/BAT. We compare these results with luminosity relations on the LGRBs and SGRBs. In addition, we examine the spectral lag relations of spike and extended emission component of the EGRBs detected by CGRO/BATSE, Konus/WIND, Swift/BAT, Fermi/GBM and compare to each other. We find that the luminosity relations of the EGRBs present different results with the LGRBs and the SGRBs. In the spectral lag relations, extended emission component expresses opposite results compared with spike component. Furthermore, the spectral lag relations from the four instruments came up with different outcomes to each other.