The particle versus the future event horizon in an interacting holographic dark energy model

Choosing the future event horizon as the horizon of the. at Friedmann - Lemaitre - Robertson - Walker universe, we show that the interacting holographic dark energy model is able to explain the phantom divide line crossing. We show that if we take the particle event horizon as the horizon of the universe, besides describing the omega = - 1 crossing ( based on astrophysical data), we are able to determine appropriately the ratio of dark matter to dark energy density at the transition time. In this approach, after the first transition from the quintessence to the phantom phase, there is another transition from the phantom to the quintessence phase which avoids the big rip singularity.