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arXiv · 1108.5780

EURONEAR - Recovery, Follow-up and Discovery of NEAs and MBAs using Large Field 1-2m Telescopes

O. Vaduvescu·M. Birlan·A. Tudorica·A. Sonka·F. Pozo N.·A. Barr D.·D. J. Asher·J. Licandro·J. L. Ortiz·E. Unda-Sanzana·M. Popescu·A. Nedelcu·D. Dumitru·R. Toma·I. Comsa·C. Vancea·D. Vidican·C. Opriseanu·T. Badescu·M. Badea·M. Constantinescu
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Abstract

We report on the follow-up and recovery of 100 program NEAs, PHAs and VIs using the ESO/MPG 2.2m, Swope 1m and INT 2.5m telescopes equipped with large field cameras. The 127 fields observed during 11 nights covered 29 square degrees. Using these data, we present the incidental survey work which includes 558 known MBAs and 628 unknown moving objects mostly consistent with MBAs from which 58 objects became official discoveries. We planned the runs using six criteria and four servers which focus mostly on faint and poorly observed objects in need of confirmation, follow-up and recovery. We followed 62 faint NEAs within one month after discovery and we recovered 10 faint NEAs having big uncertainties at their second or later opposition. Using the INT we eliminated 4 PHA candidates and VIs. We observed in total 1,286 moving objects and we reported more than 10,000 positions. All data were reduced by the members of our network in a team effort, and reported promptly to the MPC. The positions of the program NEAs were published in 27 MPC and MPEC references and used to improve their orbits. The O-C residuals for known MBAs and program NEAs are smallest for the ESO/MPG and Swope and about four times larger for the INT whose field is more distorted. The incidental survey allowed us to study statistics of the MBA and NEA populations observable today with 1--2m facilities. We calculate preliminary orbits for all unknown objects, classifying them as official discoveries, later identifications and unknown outstanding objects. The orbital elements a, e, i calculated by FIND_ORB software for the official discoveries and later identified objects are very similar with the published elements which take into account longer observational arcs; thus preliminary orbits were used in statistics for the whole unknown dataset. (CONTINUED)

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O. Vaduvescu, M. Birlan, A. Tudorica, A. Sonka, F. Pozo N., A. Barr D., D. J. Asher, J. Licandro, J. L. Ortiz, E. Unda-Sanzana, M. Popescu, A. Nedelcu, D. Dumitru, R. Toma, I. Comsa, C. Vancea, D. Vidican, C. Opriseanu, T. Badescu, M. Badea, M. Constantinescu. 2011-08-29. EURONEAR - Recovery, Follow-up and Discovery of NEAs and MBAs using Large Field 1-2m Telescopes. https://doi.org/10.1016/j.pss.2011.07.014

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