Improving the Photometry of the Pi of the Sky System

The “Pi of the Sky” robotic telescope was designed to monitor a significant fraction of the sky with good time resolution and range. The main goal of the “Pi of the Sky” detector is to look for short timescale optical transients arising from various astrophysical phenomena, mainly for the optical counterparts of Gamma Ray Bursts (GRB). The system design, the observation methodology and the algorithms that have been developed make this detector a sophisticated instrument for looking for novae and supernovae stars and for monitoring blasars and AGNs activity. The final detector will consist of two sets of 12 cameras, one camera covering a field of view of 20◦ ×20◦. For data taken with the prototype detector at the Las Campanas Observatory, Chile, photometry uncertainty of 0.018–0.024 magnitudo for stars 7–10m was obtained. With a new calibration algorithm taking into account the spectral type of reference stars, the stability of the photometry algorithm can be significantly improved. Preliminary results from the BGInd variable are presented, showing that uncertainty of the order of 0.013 can be obtained.

“Pi of the Sky” Detector

“Pi of the Sky” experiment has been designed for continuous observations of a large part of the sky, in search for astrophysical phenomena characterized by short timescales, especially for prompt optical counterparts of Gamma Ray Bursts (GRBs). Other scientific goals include searching for novae and supernovae stars and monitoring of blasars and AGNs activity. “Pi of the Sky” is a fully autonomous, robotic detector, which can operate for long periods of time without a human supervision. A crucial element of the detector is an advanced software for real-time data analysis and identification of short optical transients. The most important result so far has been an independent detection and observation of the prompt optical emission of the “naked-eye” GRB080319B.