ATLAS Insertable B-Layer Technical Design Report Addendum

This document is an addendum of the ATLAS IBL TDR of September 2010. This document describes the most significant changes to the project since that time and provides an update on several technology choices. In particular it discusses the “Mixed Scenario” where staves are considered to be populated in the centre with two-chip planar sensor modules and with single-chip 3D sensors at the two extremities. Several related changes to the services design and a more detailed description of the stave assembly procedure are included. Finally, the proposed diamond beam monitor is presented, which uses the same FE-I4 ASIC together with diamond sensors originally developed as part of the IBL R&D programme.