EUSO-SPBII mission and calibration

The Extreme Universe Space Observatory - Super Pressure Balloon (EUSO-SPBII) mission will measure \v{C}erenkov- and fluorescence-emission of ultra-high energy cosmic rays (UHECR) and search for $\tau$-neutrinos. The instrument will have UV/UV-visible sensitivity to measure PeV and EeV-scale cosmic rays. The planned launch date is 2023 from Wanaka, New Zealand, with a flight duration target of 100 days. \\ The payload consists of two optical 1-meter aperture telescopes. The fluorescence telescopes points down. Its field of view is FoV$_{FD} = 3\times \left(11 \times 11\right)^o$. The \v{C}erenkov telescopes points towards the Earth's limb. Its field of view is FoV$_{CH} = \left( 6.4\times 12.8 \right) ^o$. Telescope integration and laboratory calibration will be performed in Golden, Colorado. The main parameters determined in laboratory tests are the the point spread function (PSF) and the efficiency of the integrated telescope. An 1-m diameter parallel test beam will be used in these tests. Field tests will include an end-to-end test of the fully integrated instruments with the help of a steerable laser system, point sources and stars. A goal of the field campaign is the validation of the trigger threshold.