Mass measurement of right-handed scalar quarks and time measurement of hadronic showers for the compact linear collider

The Compact Linear Collider (CLIC) is a concept for a 48.3km long e+ e- accelerator with a center-of-mass energy of 3TeV. Its purpose is the precise measurement of particles discovered by the LHC as well as the discovery of yet unknown particles. The International Large Detector (ILD) is one of its detector concepts which was specifically designed for the usage of the Particle Flow Algorithm. This thesis is divided into two parts, both within the context of CLIC. In the first part of this thesis the unprecedented measurement on time structure of hadronic showers in calorimeters with tungsten absorber material, which is used in the ILD concept for CLIC, will be presented. It shows the development and the construction of a small testbeam experiment called Tungsten Timing Testbeam (T3B) which consists of only 15 scintillator tiles of 30mm x 30mm x 5mm, read out with Silicon Photomultipliers which in turn were connected to USB oscilloscopes. T3B was placed downstream of the CALICE tungsten analog hadron calorimeter (W-AHCal) during beam tests performed at CERN in 2010 and 2011. The resulting data is compared to simulation obtained with three different hadronic shower physics models of the \geant~simulation toolkit: QGSP_BERT, QGSP_BERT_HP and QBBC. The results from 60GeV high statistics run show that QBBC and QGSP_BERT_HP are mostly consistent with the testbeam data, while QBBC, which is lacking a sophisticated treatment of neutrons, overestimates the late energy depositions. The second part of this thesis presents one out of the six benchmark processes that were part of the CLIC Conceptual Design Report (CDR) to verify the detector performance at CLIC. This benchmark process is the measurement of the mass and cross-section of two supersymmetric right-handed scalar quarks. In the underlying SUSY model these almost exclusively decay into the lightest neutralino (missing energy) and the corresponding standard model quark (jet). Within this analysis pile-up from beam induced background of gamma gamma -> hadron is rejected by choosing the hadron variant of the kt-algorithm as it is implemented in the FastJet library. Standard Model processes mimicking the signal event topography are rejected with a forest of Boosted Decision Trees using the Toolkit for Multivariate Analysis (TMVA). The squark mass is extracted by constructing the MC distribution and fitting it to templates generated with different squark masses. The results for the mass and cross-section are consistent with the input generator values and show that sub-percent accuracy for the masses of heavy strongly interacting particles can be reached with CLIC.