Measurements of supersymmetry with the ATLAS experiment at the LHC

Abstract: If supersymmetry exists at the electroweak scale, then it should be possible to discover it at CERN's next accelerator, the Large Hadron Collider (LHC). The phenomenology predicted by the supergravity inspired mimmal supersymmetric standard model (SUGRA) is examined in detail. It is demonstrated that the ATLAS experiment wiIl be able to messure masses and branching ratios of supersymmetric particles accurately, which will allow fundamental parameters of the SUGRA model to be constrained. The consequences of baryonic R-parity violation for measurements on supersymmetric particles are investigated.The development of an analogue optical link for the readout of LHC detectors is described. In particular, the design and performance of a silicon PIN-diode array is presented. The effect of neutron radiation on semiconductor light emitters and optical fibres at cryogenic temperature (-184°C) has been investigated.