Enhancing the limiting sensitivity of optical/infrared interferometry with natural guide star adaptive optics: happy couples or bad bed-fellows?

摘要

Enhancing the limiting sensitivity of optical/infrared interferometry is one of the "holy grails" of interferometricresearch. While the use of adaptive optics is in principle attractive, a number of issues suggest that its abilityto enhance the sensitivity of ground-based arrays is less clear. Indeed, the ultimate sensitivity of an array maybe limited by any of the multiple active and photon-hungry subsystems that comprise its whole. In this paperwe investigate the limiting sensitivity of interferometer arrays using unit telescopes of moderate size (i.e. withD ≤ 4 m) equipped with natural guide star adaptive optics systems. We focus on how to realise the best limitingsensitivity for observations in the near-infrared. We nd that for Vega-type targets, i.e. those that have similarmagnitudes at all wavelengths, the use of an adaptive optics system can provide enchancements in limitingsensitivity of up to 1.5 magnitudes. However, for redder targets this improvement can decrease dramatically, andvery similar sensitivity (Δim/isublimiting/sub ≤ 0.5) can be obtained with arrays using 1.5m-class apertures and tip-tilt correction alone.© (2012) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.