CODEX (COsmic Dynamics and EXo-earth experiment) is an optical, very stable, high spectral resolution instrument proposed for the European Extremely Large Telescope (E-ELT). CODEX is currently undergoing the Phase A feasibility study, which is led by ESO in collaboration with the Cambridge Institute of Astronomy (UK), Instituto de Astrofísica de Canarias (Spain), Osservatorio Astronomico di Trieste-INAF and Osservatorio Astronomico de Brera-Merate-INAF (Italy), and the Observatoire Astronomique de l'Université de Genève (Switzerland).
CODEX is designed as a single-object fibre-fed spectrograph with a spectral coverage of 350-720 nm and with a wavelength resolution of R >= 120,000, working under natural seeing conditions, and capable of radial velocity measurements with an accuracy of 2 cm/s over decades. Key to reaching this ambitious stability goal is the laser frequency comb - a novel calibration source.
CODEX will allow us to tackle a variety of exciting scientific questions which are part of the formidable science case for the E-ELT. The phase A study team has picked the following five Show Cases to demonstrate the ground-breaking capabilities CODEX will offer:
- a measurement of the change of the expansion rate of the Universe with time;
- the detection of Earth twins in the Habitable Zone of solar-type stars;
- the study of the assembly history of the Milky Way through nucleochronometry of metal-weak stars;
- the study of the interplay of galaxies and the instergalactic medium from which they form;
- a much improved test of the stability of the fundamental constants of Physics.
CODEX consortium formed by: