First results from the FINUDA experiment at DA phi NE

In spring 2003 the FINUDA detector was installed at the 0 factory DA Phi NE in the Laboratori Nazionali di Frascati of INFN (Italy). In October 2003 the commissioning of the apparatus was accomplished and the first data taking started with a set of nuclear targets (6)Li, (7)Li, (nat)C, (27)Al, (51)V. The data collection will continue until a total integrated luminosity of 250 pb(-1) is recorded. Light and medium A hypernuclei will be abundantly produced by the strangeness exchange reaction induced by the stopped K(-) coming from the decay of phi (1020) mesons. The aim of the experiment is to simultaneously measure the excitation energy spectra of the produced hypemuclei, with a resolution better than 1 MeV, the lifetime of the A embedded in the different hypernuclei and the partial widths Gamma(pi), Gamma(np) and Gamma(nn) for mesonic and non-mesonic hypernuclear decays. Information on neutron-rich hypernuclei and rare hypernuclear two-body decays might be available too, with the statistics that will be collected at the end of the run. In the present paper, first results concerning in-beam detector calibration, spectrometer performances and very preliminary hypernuclear formation and decay spectra will be presented. (c) 2005 Elsevier B.V. All rights reserved