Initial impact parameter resolution of the new SLD vertex detector

During 1996 the SLD collaboration completed the construction of, and began the operation of, a new vertex detector (VXD3). This detector, based on 96 CCD’s each of 13cm2 area, is an upgrade of the original vertex detector of SLD (VXD2), and is made possible by advances in the technology of CCD detectors. New front-end electronics and a new data acquisition system were developed for this upgrade. Its improved characteristics will enhance many SLD measurements, and open the possibility to observe Bs0-mixing. More than 50000 Z events obtained with the new vertex detector have been analyzed. Results on the new detector performance (including resolution evaluation) from this first data are presented.