A Forward Silicon Strip System for the ATLAS HL-LHC Upgrade

The LHC is successfully accumulating luminosity at a centre-of-mass energy of 8 TeV this year. At the same time, plans are rapidly progressing for a series of upgrades, culminating roughly eight years from now in the High Luminosity LHC (HL-LHC) project. The HL-LHC is expected to deliver approximately five times the LHC nominal instantaneous luminosity, resulting in a total integrated luminosity of around 3000 fb-1 by 2030. The ATLAS experiment has a rather well advanced plan to build and install a completely new Inner Tracker (IT) system entirely based on silicon detectors by 2020. This new IT will be made from several pixel and strip layers. The silicon strip detector system will consist of single-sided p-type detectors with five barrel layers and six endcap (EC) disks on each forward side. Each disk will consist of 32 trapezoidal objects dubbed “petals”, with all services (cooling, read-out, command lines, LV and HV power) integrated into the petal. Each petal will contain 18 silicon sensors grouped in to six rings with as many different sensor designs. The groups involved in the petal project have now entered the prototyping phase, where a small version of a petal (the “petalet”) will be build to study a number of EC-related issues. For this petalet, dedicated sensors have been designed and produced by CNM Barcelona. Matching front-end readout electronics have been developed in house, and have been glued onto the sensors to form the first petalet modules. This presentation summarises the status of the R&D and prototyping work for the petal program. After an overview of the design of the new strip tracker, we will motivate the layout of the EC system. We will then present the assembly of modules and discuss the performance of the first set of EC modules that has been build.