CUBES - Phase A

Understanding the origins of the elements in the periodic table has a prominent role in both astronomy and nuclear physics. Indeed, production of the chemical elements that we are made of and use every day in our lives is one of the most profound questions we can ask. Each chemical isotope has a complex production channel, which includes numerous nuclear reactions to synthesise a single isotope. The spectral features of more than a quarter of the chemical elements are only observable at near-UV wavelengths, but the low efficiencies of current instrumentation limit studies to a handful of the brightest objects. To calibrate and test theoretical predictions of stellar evolution and nucleosynthesis we require access to near-UV observations of a much larger number and wider diversity of stars in the Milky Way.
The Extremely Large Telescopes (ELTs) under construction are optimised for infrared observations, such that the current 8-10m class observatories will remain competitive in the near-UV for the foreseeable future. Indeed, there has been a community aspiration for an optimised near-UV spectrograph on ESO's VLT for over a decade. CUBES will deliver this, providing a factor of ten gain in efficiency, combined with the spectral resolving power needed for quantitative stellar spectroscopy. With access to the spectral richness of the near UV, CUBES will provide answers to fundamental questions on nucleosynthesis of chemical elements in the Galaxy.