Upgrade 1 & Upgrade 2 Studies of the VELO detector

Upgrade 1 Study: Removing or disabling stations in the VELO detector The Vertex LOcator (VELO) detector, part of the LHCb experiment at CERN, is a silicon pixel detector which tracks particles produced in collisions and reconstructs primary vertices of b-hadrons. Upgrade 1 of the VELO detector consists of twenty-six stations, numbered from zero to 25, each composed of two hybrid silicon pixel modules. A limited number of modules will be produced, and should some of them be faulty, it is useful to know where to place them with minimal effect on the performance of the detector. The goal of this study is therefore to observe what effect removing or disabling one of these stations might have on detector performance, specifically the acceptance and IP resolution. The stations which are removed or disabled are the last three stations in the detector: station 23, station 24, and station 25.