Diffractive $\rho^0$ photoproduction at HERA

From a sample of over 989'000 events taken at the experiment H1 using the new Fast Track Trigger (Ftt), a new measurement of the differential cross section for diffractive p" photoproduction is performed in the kinematic range 20 < W-m < 90 GeV and |r| < 3 GcV2. The large data sample allows for a measurement of the cross section double differentially in W1[, and t and thus the energy dependence of this process for eight / values in a single experiment. From this data, the pomeron trajectory in elastic p° photoproduction is determined to be aF (f) = 1.097 ± 0.004 (ataf)tU öos (*W*) + (0.133 ± 0.027 (stat) 1 o o^o («tf*)) GeV-2 • t. In 2002 the first complete readout chip (PS143) for the pixel detector at the Compact Muon Solenoid (CMS) became available at the Paul Scherrer Institut (PSI), Villigen. After extensive tests of the single readout chip, the first prototype modules were assembled and tested electrically. The experience obtained from these modules was used to optimize the next generation of modules and to establish an efficient and simple assembly line for mass production of these modules for the CMS experiment at the Large Hadron Collider (LHC).