2. SELEX experiment

     The SELEX experiment (E781) at Fermilab is a fixed target experiment aimed at studying charm baryon production in the forward hemisphere and charm baryon spectroscopy. However, the versatility of the apparatus also allowed for the study of such reactions as elastic scattering of electrons on S - -hyperons (in inverse kinematics), scattering of S - , p - and p on nuclei and some others. PNPI has made a significant contribution to the apparatus of the SELEX experiment, providing good particle identification (beam and electron transition radiation detectors) and tracking, capabilities (multiwire proportional chambers). The readout electronics for these detectors and for some other detectors used at SELEX was also fabricated at PNPI. SELEX has measured the differential cross sections for ,, , , and production by S - , p - and p beams at nuclear targets as functions of xF and pt. Lifetimes of , D0, D+, D- and Ds have been measured. A Cabibbo suppressed --> pK- p + decay has been observed for the first time. SELEX has measured the total cross sections for interaction of S - , p - and p on nuclear targets (Cu, Be, C) in a broad momentum range around 600 GeV/c. For the first time, the S - -hyperon charge radius has been measured. New data on L 0 and S + polarization have been obtained. Also, the radiative decay width of the a2(1320)- meson has been measured and doubly charmed baryon has been observed for the first time.
(See SELEX)
(For more detail review see articles "Physics Results from SELEX" in PNPI HEPD Report "Main Scientific Activities 1997-2001"
and
"NEW RESULTS FROM SELEX" in PNPI HEPD Report " Main Scientific Activities 2002-2006" - pages 73-83).

Current projects and recent results