The GFTs, two robotic 1-meter class telescopes (one managed by France, an other one by China), will point automatically their field-of view towards the space-given error box within tens of seconds after the alert reception and will provide panchromatic follow-up (visible to near-infrared). They will contribute to the improvement of the link between the scientific payload and the largest telescopes by measuring the celestial coordinates with an accuracy better than 0.5'', and by providing an estimate of its photometric redshift in less than 5 min after the beginning of the observations. These information will be available to the scientific community through an alert message. Evenly placed on the Earth (one in South America in a place to be defined, the other one in China), they will be in a position to start the research of the GRB optical emission immediately after the alert reception in more than 40 % of the cases.

All the alerts of any new transient candidate will be transmitted from the scientific payload to the ground in real-time via a VHF real-time network, which is based on the successful experience of the Hete-II mission. The prompt alert will be distributed to the scientific community in the first minutes after the on-board detection through the GCN network. Main characteristics of the burst, the useful ones for follow-up campaigns, will be determined from a subset of data downlinked in real-time through the VHF network, before the full data are available through the X-band. A follow-up program more...