ausblenden:
Schlagwörter:
Hyperon Lambda Xi Omega pA-collisions silicon sensors tracking HERA-B LHCb QGP
Zusammenfassung:
The topics of this thesis are the measurements of hyperon production in proton-nucleus collisions at a center-of-mass energy of 41.6 GeV with the Hera-B detector located at DESY, Hamburg (Germany), and the design of silicon microstrip sensors for the LHCb experiment at CERN, Geneva (Switzerland). Lambda, Xi and Omega hyperons and their antiparticles were reconstructed from 113.5*10^6 inelastic collisions of protons with fixed carbon, titanium and tungsten targets. With these samples, antiparticle-to-particle ratios, cross sections integrated for the accessible kinematic region of Hera-B and single differential cross sections as function of transverse momentum, $d\sigma/dp_T^2$ (for Lambda and Xi) and rapidity, $d\sigma/dy$ (for Lambda only), have been been measured as well as the dependence of these quantities on the atomic number of the target nucleus, as parameterized using the Glauber model. The obtained ratios follow the same trend as found for the energy dependence of measurements from nucleus-nucleus collisions. Silicon microstrip sensors have been designed for the tracking system of the LHCb detector. Evaluating the performance in beam tests at CERN, the strip geometry and sensor thickness were varied optimizing for a large signal-to-noise ratio, a small number of read-out channels and a low occupancy. The detector is currently being built to be operational for first proton-proton collisions in autumn 2007.
