The Tracking Ultraviolet Setup (TUS) was the first orbital detector aimed to check the possibility of recording ultra-high energy cosmic rays (UHECRs) at E≳100 EeV by measuring the fluorescence ...signal of extensive air showers in the atmosphere. TUS was an experiment funded by the Russian Space Agency ROSCOSMOS, and it operated as a part of the scientific payload of the Lomonosov satellite since April 2016 till late 2017. During its mission, TUS registered almost 80,000 events in its main operation mode, with a few of them being sufficiently interesting to be more deeply scrutinized as they showed light profile and duration similar to UHECR events, even though much brighter. At the same time, the data acquired by TUS in different acquisition modes have been used to search for more exotic matter such us strangelets and nuclearites, and to measure occurrence, time profile and signal amplitude of different classes of transient luminous events among other scientific objectives, showing the interdisciplinary capability of a space-based observatory for UHECRs. In this paper, we report a selection of studies and results obtained with the TUS telescope which will be presented and placed in the contest of the present and future missions dedicated to the observation of UHECRs from space such as Mini-EUSO, K-EUSO and POEMMA.
Radio-detection is becoming an established technique for the detection of air showers induced by cosmic particles. This is in particular true at the highest energies, where very large detection areas ...are required. A proper description of the shape of the radio wavefront emitted by air showers may allow to reconstruct the properties of its parent particle. In this article, we show that for showers with zenith angles larger than 60° – those targeted by giant radio arrays detecting extensive air showers induced by cosmic particles –, a point-source-like description of the radio wavefront allows to constraint the lateral position of the shower axis within a few meters.
Following, we show that the reconstructed longitudinal position of this point source is correlated with the nature of the cosmic rays initiating the shower. Further systematic studies are pending to determine the robustness of this parameter and its validity as a proxy for cosmic ray composition studies.
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