Present and future of RIKEN RI Beam Factory (RIBF)


T. Motobayashi;


RIKEN Nishina Center, Japan


Five years have passed since the first beam of the new facility of RIKEN RIBF (RI Beam Factory) was extracted in the end of 2006.  RIBF is an accelerator complex providing wide range of light- and heavy-ion beams.  Especially its capability of creating nuclei very far from the stability via projectile fragmentation and projectile fission was demonstrated by several new results of isotope production, lifetime measurements for several r-process nuclei, Q-moment measurements with a noble technique, direct reaction experiments including inelastic, nucleon removal, charge exchange reactions in inverse kinematics.  These studies used the BigRIPS fragment separator, ZeroDegree spectrometer for analysis of reaction products, high-resolution spectrograph SHARAQ, and NaI(Tl) based gamma-ray detector array DALI2.  To fully use the research opportunities, RIBF host recently the RISING Ge detector array from GSI.  The collaboration program called EURICA (EUro ball RIken Cluster Array) has started, and a variety of experiments of beta-gamma and isomeric-gamma measurements will be performed in this and next years.  Another program with the spectrometer SAMURAI, the major part of which has been completed in this spring, will start with several neutron-ion coincidence experiments for studying unbound states in light neutron-rich nuclei.   SAMURAI is a superconducting spectrometer with large-gap, large momentum bite, and large solid angle, which enables measurements of n-gamma, p-gamma or multi-particle correlation.  Several international collaborations are developing detectors attached to SAMURAI.  In near future, the facility SR2 for electron-RI scattering using the idea of SCRIT (Self Confining RI Target) will start its operation.  The talk will cover also other projects such as the "Rare RI-ring".  Its major objective is mass-measurements of nuclei that are "rarely" produced and injected to the ring event-by-event.