Design and first results of the nuclear microprobe in Cracow

A new nuclear microprobe has been constructed at the Van de Graaff accelera tor (HVEC, KN-3000) in the Institute of Nuclear Physics in Cracow. The focu sing system is based on two doublets of magnetic quadrupole lenses forming a "Divided Russian Quadruplet" geometry. Numerical calculations of the ion optics are published elsewhere [V. Brazhnik, S. Lebed,W. Kwiatek, Z. Stachu ra, M. Cholewa, D. Jamieson, G. Legge, Nucl. Instr, and Meth. B 130 (1997) 104]. Tn the present work details of the design are shown and the first exp erimental results are compared with the theoretical expectations. The advan tage of the described construction is a short total length of the microprob e of 230 cm. A so short microprobe may be very convenient in some applicati on to biophysics where a vertical position of the beam line is preferable. Also, because of the short length of the system, spherical and chromatic ab errations only slightly influence the final resolution of the microprobe. ( C) 1999 Elsevier Science B.V. All rights reserved.