High-energy neutrinos from late-time jets of GRBs

Short gamma-ray bursts are sometimes accompanied by a component called extended emission, while long gamma-ray bursts are sometimes accompanied by an X-ray emission component called an X-ray flare. These emission components last for several hundred seconds after the prompt emission, suggesting that the central engine of the gamma-ray burst is active for a long time, producing a jet. However, the nature of the jet produced by such long-term activity (the late jet) is not clear. To explore the nature of the late jet, we have studied the observability of high-energy neutrinos associated with the late emission as a function of the jet parameters. In this talk I will show them and how the observability of neutrinos can provide insight into the nature of the late jets.