Letter of Intent for the LHCb Upgrade

The primary goal of LHCb is to measure the effects of new particles or forces beyond the Standard Model. Results obtained from data collected in 2010 show that the detector is robust and functioning well. While LHCb will be able to measure a host of interesting channels in heavy flavour decays in the upcoming few years, a limit of about 1 fb^ 121 of data per year cannot be overcome without upgrading the detector. The LHC machine does not face such a limitation. With the upgraded detector, read out at 40MHz, a much more flexible software-based triggering strategy will allow a large increase not only in data rate, as the detector would collect 5 fb^ 121 per year, but also the ability to increase trigger efficiencies especially in decays to hadronic final states. In addition, it will be possible to change triggers to explore different physics as LHC discoveries point us to the most interesting channels. Our physics scope extends beyond that of flavour. Possibilities for interesting discoveries exist over a whole variety of phenomena including searches for Majorana neutrinos, exotic Higgs decays and precision electroweak measurements. Here we describe the physics motivations and proposed detector changes for exploring new phenomena in proton-proton collisions near 14 TeV centre-of-mass energy