Low-resolution spectroscopic surveys with CONCERTO at APEX
CONCERTO is a new instrument planned to be installed in the APEX Cassegrain Cabin in early 2021. It is a spectrometer with an instantaneous field of view exceeding 300 Sq. arcmin. and a spectral resolution of 1.5 GHz. It covers the frequency band 120-360 GHz. The main scientific aim of CONCERTO is to map in three dimensions the fluctuations of the CII line intensity in the reionisation and post-reionisation epoch (z=4.5-8.5). This technique, known as "intensity mapping", will allow to answer the questions of whether dusty star-formation contributes to early galaxy evolution, and whether dusty galaxies play an important role in shaping cosmic reionization. CONCERTO will be one of two instruments in the world to perform intensity mapping of the CII line. 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 follow-up of Herschel and SCUBA-2 deep surveys (with the longer wavelength of CONCERTO probing to higher redshifts, and simultaneous redshift identification available through lines), the observation of local and intermediate-redshift galaxies, and the study of Galactic star-forming clouds. CONCERTO will also observe the CO intensity fluctuations arising from galaxies at z=0.3-2, giving the spatial distribution and abundance of molecular gas over a broad range of cosmic time. In this talk, I will present the CONCERTO experiment and review its major scientific goals.