1. Institute of Electronic Materials Technology, Wólczyńska 133, PL-01-919 Warsaw, Poland
2. Institute of Experimental Physics, University of Warsaw, Hoża 69, PL-00-681 Warsaw, Poland
3. Institute of Atomic Energy, PL-05-400 Otwock-Świerk, Poland
4. HASYLAB at DESY, Notkestr. 85, D-22603 Hamburg, Germany