ON THE X-RAY POSITION AND DEEP OPTICAL IMAGING OF THE NEUTRON-STAR CANDIDATE RXJ1856.5-3754

We present X-ray and optical studies of the ROSAT source RXJ1856.5-375 4, a neutron star candidate. With recent optical observations of a pot ential optical counterpart to another Xray source in the field and cor recting the X-ray positions for two effects not taken into account bef ore, we determine the ROSAT X-ray source position and its error, both different from previous work. Also, we present deep optical imaging in B and V obtained with the ESO - MPI 2.2 m telescope on La Silla and i n B and R obtained with the Keck telescope.