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arXiv · 2003.06539

Measures of 62 Southern Pairs

Matthew James·Rod Letchford·Graeme L White·Meg Emery·Stephen Bosi
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Abstract

We report lucky imaging observations of 62 pairs at mid-southern declinations sourced from the WDS with separations larger than 4 arc seconds and magnitude less than 10. The measures comprise separations and PA calibrated against Alpha Centauri AB and drift scans, presented as weighted means of these two calibration methods, with formal internal uncertainties \delta\rho = 80 mas and \delta PA = 0.056(deg). We also compare our measures against 1) extrapolated historic measures, 2) GAIA DR2 data and 3) measures determined from HIPPARCOS and GAIA observations. Our best estimate of our bias against these 3 databases are \rho \approx 10 \pm 30 mas and PA \approx 0.04 \pm 0.08(deg). These formal uncertainties are consistent with the internal uncertainties of \delta\rho = 80 mas and \delta PA = 0.056(deg). We also report Rectilinear Elements for 61 pairs, Grade 5 Orbital Elements for 5 pairs and suggest 5 pairs as optical doubles (4 of which are new).

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Matthew James, Rod Letchford, Graeme L White, Meg Emery, Stephen Bosi. 2020-03-14. Measures of 62 Southern Pairs. https://arxiv.org/abs/2003.06539

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