To fulfil its objectives, the SVOM mission will use ground facilities in addition to the systems dedicated to space platform control and command tasks:
- GFT (Ground Follow-up Telescope) (1 French GFT and 1 Chinese GFT)
Robotic telescopes designed to mease the burst celestial coordinates with high accuracy in less than four minutes after receiving an alert (location accuracy of one arcsecond), to measure the photometric evolution of the afterglow in several spectral bands and to supply a photometric evaluation of its redshift.
The French GFT located in Mexico, has a 1.30 m diameter mirror with one visible and one infrared band (0.4 – 1.8 microns)
The Chinese GFT, located in China, is equipped with a 1 m diameter mirror that observes in the visible (0.4 – 0.95 microns)
- GWAC (Ground Wide Angle Camera, supplied by China)
Set of ground telescopes pointing towards the same region of the sky as the ECLAIRs instrument. Designed to detect any emission in the visible domain before a burst in the gamma-ray domain.
The GWAC cameras are equipped with an 18 cm diameter telescope in the visible band (0.5 – 0.85 microns).
- Alert network (supplied by France)
Entity assuring permanent contact from the satellite to ground, able to receive at any time the alert signal delivered by the satellite and to transmit it in less than a minute to the French Science Centre (FSC). This network is also used to transmit part of the science data in near-real time.
- FSC (French Science Centre)
Science centre where alert data are automatically analysed in near-real time by automata, which then relay the alert to the large telescopes. Alert data are also analysed by several French and Chinese scientists taking turns to ensure 24/7 operational scientific monitoring.
Animation showing how the satellite and ground segment interact after an alert, courtesy of CEA.