The Phase 2 Upgrade of the CMS Inner Tracker

Abstract

A new silicon tracker will be built for the Phase 2 Upgrade of the CMS experiment to fully exploit the increased luminosity delivered by the HL-LHC. The innermost part, called the Inner Tracker, will be exposed to extreme conditions such as unprecedented radiation levels of 1.2Grad and 2.3×1016neq/cm2 and hit rate of 3.2GHz/cm2. The new Inner Tracker relies on many novel solutions and technologies that allow for a design of a light and radiation-hard pixel detector of high performance. The hybrid pixel modules will be composed of pixel sensors with pixel size of 2500μm2 and a new ASIC, designed in 65 nm CMOS technology, developed by the RD53 collaboration. A novel scheme of serial powering will be deployed to power the pixel modules and new technologies will be used for a high bandwidth readout system. The mechanics will be lightweight, based on carbon-fibre material and two-phase CO2 cooling. In this contribution, the design of the CMS Inner Tracker system will be presented along with the prospective design choices.