A new vertex detector made of glass capillaries

We have developed a new detector technique that allows high quality imaging of ionizing particle tracks with very high spatial and time resolution. Central to this technique are liquid-core fibres of about 20 mu m diameter read out by an optoelectronic system including a CCD. The fibres act simultaneously as target, detector and light guides. A large-volume prototype, consisting of 5 x 10(5) capillaries of 20 mu m diameter and 180 cm length, has been tested in the CERN wide-band neutrino beam. A sample of high-multiplicity neutrino interactions was recorded, demonstrating the imaging quality of this detector. First results from the reconstruction of these events are reported, A track residual of 28 mu m and a vertex resolution of 30 mu m has been achieved. Future applications of capillary detectors for neutrino and beauty physics are being investigated within the framework of the RD46 collaboration