A CCD-based Vertex Detector for TESLA

TESLA will provide a major challenge and opportunity for flavour identification. The small-radius beam-pipe and advances in detector technology will yield unprecedented performance for b- and charm-tagging, as well as more sophisticated tools such as the separate identification of quark and anti-quark jets for both b and charm. There are several technologies which may deliver the required performance, which comprises a combination of very small pixels (for clean 2-track resolution in the core of jets), excellent mechanical stability (< 5 mµ overall measurement precision) and thin layers for acceptable multiple scattering of low momentum tracks (preferably < 0.1 % 0X). The CCD technology, building on the 307 Mpixel SLD vertex detector, offers one promising approach. This paper outlines the conceptual design of such a detector, and the R&D programme which needs to be carried out over the next few years in order to establish the feasibility of this technology to achieve the design goals set by the physics requirements. If these can be realised, TESLA will be assured of a vertex detector able to play its part as a tool for new physics and for precision measurements in the TeV regime. 2