R&D in preparation for an upgrade of CMS for the Super-LHC

The LHC machine will be upgraded to increase the luminosity by an order of magnitude to 10^35 cm-2.s-1. The date for the upgrade is not yet defined but is expected to be about 10 years after LHC starts operating. The machine parameters are not yet frozen but the clock speed is expected to be 20MHz instead of the current 40MHz. The motivation is to extend the physics reach of the LHC and to study with greater precision the discoveries expected to be made at LHC since, after several years at maximum luminosity, the statistical gains gradually decline with time, or integrated luminosity. The major part of the CMS upgrade will be to construct a new tracking detector to operate with similar performance in conditions of greatly increased secondary particle fluences, by a factor of about 20 in each bunch crossing. There are major technical challenges to copy with increased radiation damage and deliver power to the detector. If the overall performance of the present tracker is to be equalled or exceeded, lower power operation and a reduced material budget are important objectives to achieve. There is an additional new challenge to maintain the first level trigger rate at below 100kHz. The main innovation to make this possible will be to include data from the tracker in the first level hardware trigger decision, which is very novel and extremely challenging. Simulation studies form an important element of designing a new tracker and achieving the triggering objective. UK CMS plans to build on its existing expertise to contribute to the simulations, readout and triggering activities. It expects to maintain a prominent position in a future CMS where we hold well established important scientific management roles, in detector construction, computing, and physics analysis.