The Scrit Electron Scattering Facility At Riken RI Beam Factory

Abstract

The SCRIT (Self-Confining Radioactive-Isotope Ion Target) electron scattering facility has been constructed at the RIKEN RI Beam Factory. In the commissioning experiment, the ion-trapping properties of the SCRIT system were studied using stable ions. By using an electron spectrometer, the momentum transfer distribution of the electron elastic scattering of 132 Xe was measured at 150, 200, and 300 MeV, and the charge density distribution was deduced. During the measurements, a luminosity of 1.8×10 27 cm −2 s −1 was achieved with a 250-mA electron beam and only 10 8 trapped ions. Production of RIs has begun in an electron-beam-driven RI separator, and developments are underway to increase the production rate of short-lived nuclei. Soon, measurements of electron elastic scattering by short-lived nuclei will be performed.

Elastic magnetic electron scattering from deformed nuclei

“…The luminosity L, defined as the ratio of the event rate per time to the cross-section, is a key parameter to asses the feasibility of the experiment. Luminosities over 10 27 cm −2 s −1 have been already achieved at the SCRIT facility in the 132 Xe experiment [17] and similar luminosities are expected for unstable nuclei in the next future [16] that will allow to measure them. The luminosities expected in ELISe are also within similar ranges [14].…”

“…[14]. In SCRIT (Self-Confining Radioactive Ion Target), a circulating beam of electrons scatters off ions stored in a trap [15,16], and the first elastic electron scattering experiment on 132 Xe has already been performed [17].…”

The Performance Of The Scrit Detectors For Electron-RI Scattering Experiment

“…A chamber which contains the SCRIT device is installed at one of the straight lines of SR2. A detailed information and a recent progress on the SCRIT device is reported elsewhere in this proceedings [4]. To obtain the angular distribution of electron-nucleus scattering cross-section while its crosssection is still unknown, the absolute luminosity of electron-nucleus scatterings has to be measured…”