Suche nach solaren Axionen mit dem CCD-Detektor in CAST (CERN Axion Solar Telescope)

The CERN Axion Solar Telescope (CAST) experiment at CERN searches for solar axions with energies in the keV range. Axions could be produced in the Sun's core by the interaction of thermal photons with virtual photons of the strong electromagnetic field. In this experiment, the solar axions can be converted to photons in the field of a 9 Tesla superconducting magnet. At both ends of the 10 m long dipole magnet, three different X-ray detectors were installed, which are sensitive in the interesting photon energy range. This thesis is devoted to the determination of an upper limit on the axion-photon coupling constant g$_{a\gamma}$. The analysis is based on the data taken by the CCD detector in the CAST experiment during the years 2003 and 2004. First results of the 2003 data taking were published showing no significant signal above background. However, these results constrain the upper limit of the axion-photon coupling constant by a factor 5 compared to previous axion search experiments. Moreover, the result of the 2004 data improved the previous constraints from other experiments by a factor of 7. For the first time, the experimental result is better than the astrophysical bound from globular clusters.