Orbit determination of close binary systems using lucky imaging

Abstract

We present relative positions of visual binaries observed in 2009 with the FastCam 'luckyimaging' camera mounted on the 1.5-m Carlos Sánchez Telescope at the Observatorio del Teide. We obtained 424 CCD observations (averaged in 198 mean relative positions) of 157 binaries with angular separations in the range 0.14-15.40 arcsec, with a median separation of 0.51 arcsec. For a given system, each CCD image represents the sum of the best 10-25 per cent images from 1000-5000 short-exposure frames. Derived internal errors were 7 mas in ρ and 1. • 2 (9 mas) in θ . When comparing to systems with very well known orbits, we find that the rms deviation in ρ residuals is 23 mas, while the rms deviation in θ residuals is 0. • 73/ρ. We confirmed 18 Hipparcos binaries and we report new companions to BVD 36 A and J 621 B. For binaries with preliminary orbital parameters, the relative radial velocity was estimated as well. We also present four new revised orbits computed for LDS 873, BU 627 A-BC, BU 628 and HO 197 AB. This work discusses the first results on visual binaries using the FastCam lucky-imaging camera.

Dynamical Study of the Exoplanet Host Binary System HD 106515

“…Therefore, the dynamical study presented here includes 133 positions covering a time baseline of 189 yrs. We applied a weighting procedure to estimate the orbit following prescriptions detailed in Rica et al (2012). For θ values, the parabolic fit shows smaller RMS (root mean square) residuals than linear fit.…”

Binary Stars Observed With Adaptive Optics at the Starfire Optical Range

“…HIP 44127 = HR 3569 = 9 ι UMa Apparently, B and C (Figure 8) were not recorded separately from A until 2008. Therefore, the averages of the two AO measurements in 2008 (De Rosa et al 2011) are computed and used, as well as the two in 2010 (De Rosa et al 2011), the two CCD measurements in 2009 (Rica et al 2012), and our own in 2012. These last four observations are then given the higher AO/SI weight of 20 compared to unity for all others.…”