Optical Interferometry Continuation of Cavendish Astrophysics Rolling Grant

The success of the Hubble Space Telescope and the motivation for its successor, the James Webb Space Telescope, have been largely driven by the desire for images with resolutions an order of magnitude better than routinely achieved by ground-based telescopes. However, even this may be inadequate for understanding the physics underlying many important astrophysical phenomena and in many cases resolutions 10-100 times better than these flagship missions are required. Such milli- and sub-milli-arcsecond resolutions can only be delivered by optical/infrared interferometers which synthesize effective telescope diameters of 100s of meters using arrays of smaller telescopes. The Magdalena Ridge Observatory Interferometer (MROI) is an optical/IR imaging interferometer currently under construction in New Mexico in a partnership between New Mexico Tech (NMT) and the Cavendish Laboratory, Cambridge. Its Phase 1 implementation will combine light from six 1.4 m telescopes, separated by up to 350m, to permit imaging in the near-infrared with an angular resolution of 0.7 milli-arcseconds, i.e. 10 times better than a diffraction-limited 30 m-class telescope. The MROI builds on the success of other interferometers such as Georgia State's CHARA Array, the Keck Interferometer and the VLTI, which are now routinely used to tackle important astrophysical questions and which have demonstrated that interferometry can be a valuable tool for astronomers who are not interferometric specialists. By optimizing its design for the imaging of faint astrophysical targets, the MROI is expected to have a limiting sensitivity 10-100 times greater than has been realized by any optical/IR interferometer to date. It is the MROI's unique capability to deliver model-independent images at ultra-high resolution, efficiently, and at much higher sensitivity than has been previously realised that offers the most exciting potential for new science. The scope of this research will be very broad. Studies with first-generation IR-arrays have spanned topics as diverse as fundamental parameter estimation of stars, the molecular envelopes of evolved giants, the geometrical extension and evolution of novae ejecta, and the structure of AGN cores. All of these will be accessible at the MROI, though with much higher efficiency, sensitivity and completeness than has hitherto been available with the VLTI and similar current-generation arrays. The MROI is a joint activity of NMT and the Cavendish Laboratory. NMT are providing the majority of the capital funds, while Cavendish researchers - who pioneered interferometry at optical/IR wavelengths - are providing technical leadership and oversight of the array deployment. The proposed research reflects this partnership and will involve staff at the Cavendish completing three key tasks related to the commissioning of the MROI. These will be: * The development and delivery of the real-time control algorithms for the first-light instrument, a fringe tracking beam combiner. Here the goals will be to deliver the critical algorithms necessary to detect and track fringes on the faintest sources with high precision. * The design and coding of the first-light data reduction pipeline for the MROI. This software will be used to produce diagnostic measures critical for optimising the performance of the interferometer as well as producing the first science results from the MROI. * To lead the technical and scientific commissioning effort to deliver first fringes with the MROI. This activity will be led by two of the senior staff at the Cavendish who have had considerable experience of the alignment, integration and commissioning of a number of other interferometric arrays. These activities will form a significant contribution towards the completion of the array and put the UK in a leading position to exploit the science which will result from its operation.