Analysis of synchronism and response velocity in instrumental assemblies for the observation of stellar occultations

Abstract

Currently the stellar occultation technique is one of the most effective methods for observing minor bodies of the Solar System. Due to the collaborative nature of these observations, precise synchronization and short response times are necessary in instrumental assemblies. This paper presents the development of a methodology that allows for the evaluation of the temporal performance of the detectors used in the observation of stellar occultations. The software “TimesCCam” was developed, which, when being photographed by astronomical cameras, graphically represents the parameters of exposure time, dead time, and jitter referenced to UTC. The process of alignment and focus is obtained, thanks to a structure built with movement in the three axes. The methodology was applied in the evaluation of STF-8300M, ST-2000XM and QHY174M-GPS cameras, using different driver software, synchronization methods, and exposure times. In real exposure times, insignificant variations were identified. Dependency was found between the dead times and the configurations used for the CCD cameras, and it was determined that the dead time and its instability in the ST-2000XM camera prevent its use for the observation of stellar occultations. The results show that the STF-8300M camera is convenient for the observation of asteroid occultations, while the QHY174M-GPS camera given its dead time and synchronization, is suitable for the observation of occultations by trans-Neptunian objects.