EUSO-Balloon: The first flight

摘要

EUSO-Balloon is a pathfinder mission for JEM-EUSO, the near-UV telescope proposed to be installed on board the International Space Station (ISS). The main objective of this pathfinder mission is to perform a full scale end-to-end test of all the key technologies of JEM-EUSO detectors and to measure the UV background. The JEM-EUSO instrument consists of UV telescope designed to focus the signal of the UV tracks generated by Extreme Energy Cosmic Rays propagating in Earth's atmosphere, onto a finely pix-elized UV camera. The EUSO-Balloon instrument, smaller than the one designed for the ISS, was launched on August 2014 from Timmins (Ontario, Canada). The flight lasted about five hours and the instrument reached a float altitude of about 40 km. From this altitude the telescope registered, at a rate of 400 000 frames/s, the nightglow background on forests, lakes and clouds, as well as city lights and artificial air showers tracks generated by means of a laser installed on an helicopter flying inside its field of view. In this contribution we will describe the instrument and its performance during the first flight.