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Search for Small Trans-Neptunian Objects by the TAOS Project

W. P. Chen·C. Alcock·T. Axelrod·F. B. Bianco·Y. I. Byun·Y. H. Chang·K. H. Cook·R. Dave·J. Giammarco·D. W. Kim·S. K. King·T. Lee·M. Lehner·C. C. Lin·H. C. Lin·J. J. Lissauer·S. Marshall·N. Meinshausen·S. Mondal·I. de Pater·R. Porrata·J. Rice·M. E. Schwamb·A. Wang·S. Y. Wang·C. Y. Wen·Z. W. Zhang
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Abstract

The Taiwan-America Occultation Survey (TAOS) aims to determine the number of small icy bodies in the outer reach of the Solar System by means of stellar occultation. An array of 4 robotic small (D=0.5 m), wide-field (f/1.9) telescopes have been installed at Lulin Observatory in Taiwan to simultaneously monitor some thousand of stars for such rare occultation events. Because a typical occultation event by a TNO a few km across will last for only a fraction of a second, fast photometry is necessary. A special CCD readout scheme has been devised to allow for stellar photometry taken a few times per second. Effective analysis pipelines have been developed to process stellar light curves and to correlate any possible flux changes among all telescopes. A few billion photometric measurements have been collected since the routine survey began in early 2005. Our preliminary result of a very low detection rate suggests a deficit of small TNOs down to a few km size, consistent with the extrapolation of some recent studies of larger (30--100 km) TNOs.

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W. P. Chen, C. Alcock, T. Axelrod, F. B. Bianco, Y. I. Byun, Y. H. Chang, K. H. Cook, R. Dave, J. Giammarco, D. W. Kim, S. K. King, T. Lee, M. Lehner, C. C. Lin, H. C. Lin, J. J. Lissauer, S. Marshall, N. Meinshausen, S. Mondal, I. de Pater, R. Porrata, J. Rice, M. E. Schwamb, A. Wang, S. Y. Wang, C. Y. Wen, Z. W. Zhang. 2006-11-16. Search for Small Trans-Neptunian Objects by the TAOS Project. https://doi.org/10.1017/s1743921307003079

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