Large-scale exploration of exoplanetary atmospheres using JWST and E-ELT.

The JWST and EELT observatories will be coming on line in the next few years, with new capabilities at thermal infrared wavelengths (longward of 3 microns) which will open unexplored regions of parameter space, in terms of spatial and spectral resolution and for raw sensitivity. At the ATC in Edinburgh, we have both programmatic and technical leadership in the two most important instruments in this field, namely the JWST-MIRI instrument and the EELT-METIS-LMS spectrometer.

For the study of exoplanets, they will move the focus of research beyond the straightforward discovery and measurement of basic physical parameters (mass, size, orbit), into the spectroscopic measurements at a signal to noise which is sufficient to identify the rich mix of chemical constituents, abundances and excitations in a large number of targets.

Building on the foundations of terrestrial atmospheric physics, several groups around the world are developing models of exoplanet atmospheres which have the complexity necessary to interpret these spectra, including the University of Edinburgh. However, the ability to take the measured spectra and extract the chemical and physical information (the so-called 'inverse problem') requires not just a good atmospheric model, but also a rugged and accurate simulation of the spectral signature imprinted on an observation by the observatory and instrument. At the ATC we have invested a good deal of effort in developing these simulators, with MIRI's now up and running and being used to simulate planned MIRI observations of hot exo-Jupiters, where the problem of extracting the atmospheric spectra from the glare of its parent star is heavily dependent on the simultaneous accurate modelling of the planet, star and instrument.

This project includes two streams of simulator development, one one side the instrument simulators, with the incorporation of in-house expertise and knowledge about the systems they represent and on the other, the development of exoplanet atmospheric models and their parametrisation as part of the optimisation for solving the 'inverse problem'. Finally, the full system of astronomical target and observing train will be brought together in the interpretation of early science spectra.