TRASGO: A proposal for a timing RPCs based detector for analyzing cosmic ray air showers

The study of the properties of primary cosmic rays with energies above 100 TeV is only accessible indirectly through the use of detector arrays at the Earth surface. Despite the extremely high multiplicity of the air showers produced in their interactions at the highest layers of the atmosphere, only a fraction of those particles arrive to the ground over surfaces from ∼0.1∼0.1 to ∼100km2. The lack of information on the primary interaction and the low density of particles at the detection plane make the event by event analysis very complicated and usually only mean analysis are possible, sometimes with the help of simulation programs.The necessity of covering big surfaces to gather a significant sample of information usually leads to the use of big volume detectors with limited performances, giving only access to a small part of the information carried out by the swarm of secondary particles of the shower. In this article, we propose the development of an affordable detector, the TRASGO, based on timing RPCs (Resistive Plate Chambers) offering at the same time very good timing and tracking performances. TRASGO would allow a better and more accurate reconstruction of the air shower properties either working stand-alone or in big surface arrays.