The SpectromeTer for Exotic Fission Fragments (STEFF)is a 2E-2v device. It allows measurement of the velocities and energies of both fragments from the fission event. Mass may be measured either independently in each arm (Ev), or, by ignoring the momentum and kinetic energy contributions of the emitted fast neutrons and target effects, by the 2E or the 2v methods. STEFF also includes an array of 12 (5"x4") NaI scintillation detectors for gamma detection and is used in conjunction with the Manchester array of NE213 fast-neutron detectors.The fission fragments stop in two Bragg detectors the output of which are digitized as a function of time. The digitized traces may be used to measure energy loss (dE/dx) and range of the fission fragments.

STEFF is currently sited in Grenoble and is being used in experiments at the LPSC and the ILL.

The programme overlaps with experiments that use the Lohengrin mass spectrometer to futher develop the algorithms used to process data from the Bragg detectors.

This is a website for the download of data, news and information relating to STEFF.