EGU General Assembly 2021
© Author(s) 2021. This work is distributed under
the Creative Commons Attribution 4.0 License.

Estimation of the global occurrence rate of elves with Mini-EUSO

Matteo Battisti1,2, Enrico Arnone1,2, Mario Bertaina1,2, Marco Casolino3,4,5, Laura Marcelli3, and Lech Wiktor Piotrowski6
Matteo Battisti et al.
  • 1Università degli Studi di Torino, Department of Physics, Italy
  • 2Istituto Nazionale di Fisica Nucleare - Sezione di Torino, Italy
  • 3Istituto Nazionale di Fisica Nucleare - Sezione di Roma Tor Vergata, Italy
  • 4Università degli Studi di Roma Tor Vergata - Dipartimento di Fisica, Roma, Italy
  • 5RIKEN, Wako, Japan
  • 6Faculty of Physics, University of Warsaw, Warsaw, Poland

Elves are the most common type of transient luminous events, with estimates of their global occurrence rate ranging from a few to a few tens per minute. Here, we present the first derivation of the global occurrence rate of elves from Mini-EUSO observations. Mini-EUSO is a wide field of view, space-based telescope operating from a nadir-facing UV-transparent window in the Russian Zvezda module on the International Space Station. It observes the Earth’s atmosphere in the UV band with a spatial resolution of about 6.3 km and a temporal resolution of 2.5 μs. Its optical system made of two 25 cm diameter Fresnel lenses focuses the light into a square array of 48x48 pixels, each pixel being capable of single photon counting. Originally designed to detect the faint fluorescence light produced by extensive air showers induced by extreme energy cosmic rays, it was shown to be capable of detecting a wide range of atmospheric phenomena, including elves. Elves are dynamically traced by Mini-EUSO in their horizontally expanding, fast donut-shaped light emissions and can therefore be unequivocally identified. Mini-EUSO can usually detect elves whose center is just outside the field of view, following the expansion of the ring for hundreds of microseconds. Combining the number of detected elves with consideration of the time and geometries, it is possible to derive a first estimate of their global occurrence rate with Mini-EUSO, and to compare it to the literature. 

How to cite: Battisti, M., Arnone, E., Bertaina, M., Casolino, M., Marcelli, L., and Piotrowski, L. W.: Estimation of the global occurrence rate of elves with Mini-EUSO, EGU General Assembly 2021, online, 19–30 Apr 2021, EGU21-11004,, 2021.

Corresponding presentation materials formerly uploaded have been withdrawn.