CONCERTO is a new instrument that has been successfully installed in the Cassegrain Cabin of the APEX telescope in April 2021. It is a spectrometer with an instantaneous field of view exceeding 260 square arcminute and a spectral resolution up to 1.3 GHz. It is covering the frequency band 130-310 GHz. The main scientific aim of CONCERTO is to map in 3D the fluctuations of the [CII] line intensity in the reionisation and post-reionisation epoch (z>5). This technique, known as "intensity mapping", will allow us to address questions about the contribution of the dust-enshrouded star formation at z > 5, the history of metal enrichment, and the role of star-forming galaxies in shaping cosmic reionization. In addition to the main [CII] survey, we expect CONCERTO to bring a significant contribution in a number of areas, including the study of galaxy clusters (via the thermal and kinetic SZ effect), the observation of local galaxies, and the study of Galactic star-forming clouds. CONCERTO will also observe the CO intensity fluctuations arising from 0.3<z<2 galaxies, giving the spatial distribution and abundance of molecular gas at cosmic noon.
In this talk I will tell you the story of the CONCERTO adventure, from its conception to the first light. I will also review the major scientific goals of CONCERTO and show some first results.
