Exploring the structure of hadronic showers and the hadronic energy reconstruction with highly granular calorimeters

Prototypes of electromagnetic and hadronic imaging calorimeters developed and operated by the CALICE collaboration provide an unprecedented wealth of highly granular data of hadronic showers with a variety of active sensor elements and different absorber materials. In this article, we discuss detailed measurements of the spatial and the time structure of hadronic showers to characterise the different stages of hadronic cascades in the calorimeters and perform particle identification techniques. The high granularity of the detectors is exploited in the reconstruction of hadronic energy, both in individual detectors and combined electromagnetic and hadronic systems, making use of software compensation and semi-digital energy reconstruction algorithms. The results on hadronic shower measurements are obtained using different electromagnetic and hadronic calorimeters, with silicon, scintillator and gaseous active elements, and confronted with GEANT4-based simulations using different hadronic physics models.