TH-PHD-2018-010

The success of cluster-jet targets in hadron, lepton, and laser beam physics depends highlyon their performance. Therefore, a precise determination and optimisation of the targetproperties and understanding of the cluster formation process is essential.Within the work presented in this thesis, investigations and developments for andmeasurements using three different cluster-jet targets were performed: thePANDA cluster-jet target prototype for thePANDA experiment at FAIR, the MCT1S for CryoFlash atthe University of D ̈usseldorf and the jet target MCT-M for MAGIX at MESA.Laval nozzles, as key components of jet targets, originating from production processesdeveloped at the University of M ̈unster are reviewed with respect of their performance andbased upon that their developed processes were further improved yielding an optimisednozzle geometry, production processes, and a deeper insight into the complex clusterformation process.A new record hydrogen target thickness of(4.85±0.24)×10*15 atoms/cm*2 in a distanceof 2.1 m from the nozzle was achieved within this thesis work with thePANDA cluster-jettarget prototype.The high performance, state-of-the-art jet target for MAGIX at MESA was designed,built up, and set into operation. The suitability of a Mach-Zehnder interferometer toinvestigate the jet beam characteristics was shown and a well defined cluster beamwith a high range of constant target thickness of more than 30mmand a thickness of(2.1±0.2)×10*18 atoms/cm*2 directly behind the nozzle was recorded and the resultswere published [G+18]. Beam times at the MAinz MIcrotron results in elastic electron-proton cross sections and the feasibility to perform precise low energy physics like the determination of the proton radius using the jet target.The installation of a cluster-jet target at the high intensity ARCTURUS laser systemof the University of D ̈usseldorf resulted in accelerated protons with energies up to(88.0±14.5) keV, accelerated electrons, and X-rays within the framework of this thesis.Novel in this field is the stability and reproducibility of the accelerated particles. Moreover,a plasma temperature in the range of 1600 K to 4500 K by the cluster-laser interactionwith the U1 laser system was determined by the observation of Balmer spectral lines.Based on these successful results and the gained experience within this thesis, a newpowerful cluster-jet target was designed to perform extended measureme