UltraVISTA

UltraVISTA is a deep near-infrared imaging survey of the central 2 square degrees of the COSMOS field. The observations were carried out over 14 observing seasons, from December 2009 to March 2023, using the VIRCAM wide-field imager on the VISTA 4-meter telescope. The field was imaged in Y, J, H and Ks, and half of the area also in the narrow-band filter NB118. We are currently working on the final data release, DR6, based on all data ever taken, which after quality cuts amounts to 100,000 images corresponding to 2300 hours of integration. The four broad-band stacks will have a uniform depth over the field with around 175 hours of integration per pixel. The image quality in the final stacks is excellent, with a FWHM of ~0.75 arcsec. Already from the previous data releases UltraVISTA has proven to be a powerful and productive public survey. It is utilised in essentially all studies of the COSMOS field, and it provides the critical near-infrared imaging in the multi-wavelength photometry and photometric redshift catalogues of the COSMOS field such as COSMOS2020. UltraVISTA has provided breakthrough results on bright high-redshift galaxies into the reionization era at z ~ 5-8, state-of-the-art galaxy stellar mass functions out to z ~ 4, and played a key role in identifying and studying dusty star-forming galaxies. UltraVISTA continues to be relevant even in the era of JWST and Euclid. A recording of the talk is provided by ESO at https://www.youtube.com/watch?v=mzOXbOpL3hE