Velasco et al. (2016) find two resolved components, LkHα 263 A and B, at 0.41 arcsec separation, and marginal evidence for an unresolved binary or a disc in LkHα 262. The presence of
discs in some of the components offers an interesting opportunity to investigate the formation and
evolution of discs in the early stages of multiple very low-mass systems.
The AOLI data combined with previously available and newly obtained optical and infrared imaging show that the 3 components of LkHα 263 (A, B and double-disc) are co-moving,
that there is orbital motion in the AB pair, and remarkably that LkHα 262/263 is a common proper-motion system with less than 1 mas/year relative motion. So this is likely a
five-component gravitationally-bound system.
The AO system in AOLI is being commissioned at the WHT in 2016. The system includes a novel, low-order non-linear curvature wave-front sensor (WFS)
together with a 241-actuator deformable mirror, a science array of four 1024×1024 EMCCDs, allowing a range of fields of view from 120×120 down to 36×36 arcseconds and a calibration subsystem.
Thanks to the revolutionary WFS, AOLI is able to use faint reference stars (I ∼ 16.5-17.5), and thus it can be used over a
much wider part of the sky than with common Shack-Hartmann AO systems. Once AOLI is fully commissioned astronomers expect it will deliver images of only 0.04 arcsec FWHM, close to the diffraction limit of the WHT at the wavelength of the observations.
- Velasco et al., 2016, "High spatial resolution optical imaging of the multiple T Tauri system LkHα 262/LkHα 263", MNRAS, doi: 10.1093/mnras/stw1071 [ arXiv ].
- AOLI-related publications.