BOOTES

BOOTES, the Burst Observer and Optical Transient Exploring System, is a network of astronomical observatories with sites in Southern Spain, New Zealand, China, parts of the United States in Michigan and Mexico (mostly 0.6m diameter telescope with EMCCD camera at the Cassegrain focus and a g'r'i'ZY filterset. The main goal of the network is to quickly observe transient events within seconds or minutes of being detected by scientific satellites.

BOOTES provides an automated real time response to the detection of Gamma Ray Bursts GRBs. Error box size depending, it uses wide field cameras (WFC), ultra wide field cameras (UWFC) and narrow field cameras (NFC) attached to small robotic telescopes, or the telescopes themselves.

To study GRBs, it is of the utmost importance to perform prompt optical follow-up observations to detect longer wavelength transient emission associated to the GRBs; BOOTES can perform such follow ups. Its scientific objectives include:

• Simultaneous and quasi-simultaneous observations of GRB error boxes.

• Detection of optical flashes of cosmic origin.

• All-sky monitoring with the CASANDRA cameras down to 10th magnitude every 60 seconds.

• Monitoring of different types of variable objects (galactic or extragalactic) down to 20th magnitude in order to search for optical variability.

• Discovery of comets, meteors, asteroids, variable stars, novae and supernovae.

BOOTES is part, within the framework of an international collaboration led by Spain, which was initiated in order to support the ESA's satellite INTEGRAL with ground-based observations. The project also focused on performing rapid follow up observations of events detected by several spacecraft (BATSE, BeppoSAX, RossiXTE, IPN, Hete-2, Swift, and Fermi). Results in the GRB field are multifold:

• Pre-detection images: BOOTES sets up upper limits for any possible precursors.

• Simultaneous images: The first was achieved by BOOTES on February 20th, 2001, but no counterpart was detected.

• Follow-up images: Images detected with several gamma-ray bursts being discovered or monitored starting several dozens of seconds after the onset of the event.