Ultrahigh-energy cosmic rays with AugerPrime
Advisor: Petr Travnicek, Alexey Yushkov or Martina Bohacova (IP CAS)
Funding: Fully funded
The Pierre Auger Observatory  is the largest cosmic ray physics experiment in the world. It registers cosmic particles of energies far beyond the reach of any terrestrial accelerator over an area of 3000 sq. kms of Argentine pampa. The aim of the Observatory is to determine the energy spectrum and arrival directions of the particles and answer the question of their origin - whether they are produced in unknown cosmic accelerators or during the decay of hypothetical dark matter particles. The Observatory is in fact indispensable to the whole field of ultra-high energy cosmic ray physics. As this scientific field rapidly evolves, the structure, size and complexity of the Observatory need to be modified to answer the newly appearing questions in sufficient detail. This is the major motivation for the ongoing upgrade of the Observatory called AugerPrime. While the flux suppression above the GZK energies was unambiguously established by the Observatory and some hints towards the origin of cosmic ray sources were recently found, the questions of the cosmic ray composition at ultra-high energies, location of sources of these rare particles and the characteristics of hadronic interactions remain open and will be addressed by the upgraded Observatory. The AugerPrime upgrade includes installation of scintillator detectors above each surface detector station as well as a replacement of electronics with a faster and a more powerful system that provides channels for the additional detectors, increased dynamic range and processing capability, higher sampling frequency, and improved timing, calibration and monitoring. The Prague laboratory became responsible for climate tests and accelerated aging of the produced electronics boards .
We offer an experimentally focused PhD. student position based on high level data analysis. The student is supposed to contribute to the analysis topics of the Czech group of the Pierre Auger Observatory - cosmic ray composition and hadronic interactions . An alternative, hardware focused work is equally welcome. It would be related to the hardware contribution of the Prague group, which is currently focusing on new electronics for the Auger surface detector stations. The project would include the performance analysis of the new electronic systems.
Candidates for this project will be considered jointly with the project Extensive air showers as probes of hadronic interactions beyond the LHC energies.
 A. Aab et all. (The Pierre Auger
Collaboration): The Pierre Auger Cosmic Ray Observatory: Nucl. Instrum. Meth. A 798 (2015) 172 - 213.
 M. Boháčová for the Pierre Auger Collaboration: Test benches for the upgrade of the Pierre AugerObservatory electronics: POS(ICRC2019)199.
 A. Aab et al.(The Pierre Auger Collaboration): Evidence for a mixed mass composition at the 'ankle' in the cosmic-ray spectrum: Phys. Lett. B 762 (2016) 288 - 295.