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Transient Optical Phenomena

The advent and use of CCD detectors has been the panacea for increasing the accuracy and the sampling of photometric data in crowded fields. However, for obtaining a high signal to noise ratio are necessary in the most popular telescopes exposure times of the order of several minutes. This fact represents a strong limit for the detection and the analysis of optical phenomena which takes place on shorter time scales. In the broad class of transient and/or rapid optical phenomena are included several groups of variable stars such as the Flare and Flashes stars and the UV Ceti stars. Even though these objects have been observed both in the field and in stellar systems up to now we still lack detailed and homogeneous sample of photometric data. Both the large field and the very high time resolution of this detector would allow extensive detecting and measuring of these objects. Thus providing useful suggestions on the time-scale within which they approach the main sequence and on their pulsation behavior. In passing we note that the fast photometry technique can also play a key role in the detection of optical phenomena associated to soft X-ray sources belonging to Galactic stellar systems or to hard X-ray sources in the field. Finally we mention that the coupling between a large field detector, the fast photometry and the spectroscopic facilities of LBT would allow investigating the optical emission and the spectroscopic properties of transient phenomena in situ.

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next up previous contents
Next: White Dwarfs Up: The Scientific Cases for Previous: Globular Cluster and PNe
Guido Buscema
1999-01-29