Phenomenology and detection of nuclear cosmic rays
May 24, 2011
Abstract: One century after the discovery of cosmic rays ÛÒ a flux of energetic charged particles which bombards the upper layers of EarthÛªs atmosphere ÛÒ many questions remain still open on its origin, nature and transport. The precise measurement of the cosmic-ray ion flux aims to study the acceleration and propagation processes. In particular, the measurement of secondary-to-primary ratios allows to constrain propagation models very effectively due to its direct dependency to the grammage seen by the particles during their transport. The knowledge and the characterisation of the processes related to the propagation make it possible to reconstruct the cosmic-ray source spectrum and thus to constrain the acceleration processes, but also to test the existence of exotic contributions such as the annihilation of dark-matter particles. My work treats two aspects of cosmic-ray physics: the phenomenology and the detection. Concerning the phenomenological aspect, the work presented here consists in evaluating and studying the constraints on galactic cosmic-ray propagation models provided by current measurements using a Markov Chain Monte Carlo. The experimental aspect of this work concerns the participation in the construction, the validation and the data analysis of the CherCam subdetector ÛÒ a Cherkov imager measuring the charge of cosmic-ray ions for the CREAM experiment ÛÒ whose preliminary results are presented.