J. Phys. IV France 09 (1999) Pr6-145-Pr6-148
New developments in surface (e,2e) experimentsS. lacobucci1, S. Rioual2, A. Ruocco3, M. Mastropietro1 and G. Stefani3
1 IMAI-CNR, Area della Ricerca di Roma, via Salaria km 29.300, CP. 10, 00016 Monterontodo, Italy
2 LCEA, Université de Brest, 6 avenue Le Gorgeu, 29285 Brest cedex, France
3 Unita INFM Roma 3 and Dipartimento di Fisica E. Amaldi, Università di Roma Tre, via della Vasca Navale 84, 00146 Roma, Italy
This work presents the implementation of a position-sensitive detector in the Montelibretti surface (e,2e) apparatus that allows to fully define the direction of the ejected electron from the surface, and hence to improve the momentum resolution. The coincidence electronic chain and the acquisition software have been upgraded in order to achieve high data collection speed, storage of large dimension data files and fast visualisation of the results. Preliminary angle resolved (e,2e) data relative to the ionisation of the Å-1 band of highly oriented pyrolitic graphite show that a momentum resolution better than 0.2 Å-1 has been achieved without degrading the overall speed of acquisition.
© EDP Sciences 1999