Masanori Wakasugi

First Elastic Electron Scattering from Xe132 at the SCRIT Facility

The first elastic electron scattering has been successfully performed at the self-confining radioactive-isotope ion target (SCRIT) facility, the worlds first electron scattering facility for SCRIT technique achieved high luminosity (over 10^{27}  cm^{-2} s^{-1}, sufficient for determining the nuclear shape) with only 10^{8} target ions. While ^{132}Xe used in this time as a target is a stable isotope, the charge density distribution was first extracted from the momentum transfer distributions of the scattered electrons by comparing the results with those calculated by a phase shift calculation.

BEAM OPTICS SIMULATION OF RARE-RI RING AT RI BEAM FACTORY IN RIKEN

The cyclotron-like storage ring dedicated to Rare-RI Ring project consists of 6 magnetic sectors and 6 straight sections, having a circumference of 56.13 m. The magnetic sector works for both bending and focusing. The total circulation is assumed to be 1,000 turns. Over the momentum range from -1% to +1% in ∆p/p, the required isochronisity is 10-6 while the beam emittance is sevaral tens of π mm-mrad. To examine the design of cyclotron-like storage ring and fix its parameters, we have developed a high precision beam optics simulation. To achieve the precision as high as possible within a feasible computational time, we have adopted a geometrical tracking assuming a circular orbit for a small spatial segment. For that purpose, it is enough that the magnetic sector is divided into 150 sub-sectors in calculation. In each sub-sector, the magnetic field is given as a function of radial position but uniform around the vicinity of beam trajectory. The beam trajectory is evaluated in 4th order Runge-Kutta algorithm. Finally, we have achieved a precision of 10-9 in ∆T/T and a computational time of 1.8 sec on a typical PC server for ray tracing of single particle undergoing a circulation of 1,000 turns.

Ultralow-background photon-detection system for collinear laser spectroscopy of high-energy highly charged ion beams

Abstract An ultralow-background fluorescence-photon detection system has been successfully developed for the collinear laser spectroscopy of highly charged ion beams having a relativistic velocity. We applied the technology of a cryopump to a photon-detection system. A charcoal panel, optical filters and four movable collimators strongly reduced the background due to scattered photons of the incident laser beam. The background due to collisions between the ion beam and residual gas was also suppressed by improving the vacuum using a cryopump technique. With this system, we clearly observed the laser-induced fluorescence spectra of the 2S 1/2 -2P 1/2,3/2 transitions in an Li-like 11 B 2+ ion beam with a signal-to-noise ratio of 200. The ion-beam energy was 11.25A MeV and the intensity was 10 4 ions/bunch. We also demonstrated that the system has the capability of measuring the lifetimes of excited states.

First Result from Scrit Electron Scattering Facility : Charge Density Distribution Of 132 Xe

We have constructed the SCRIT electron scattering facility at RIKEN in order to realize electron scattering off unstable nuclei. Because electron scattering is the most powerful and reliable tool to study the internal structure of the atomic nuclei as demonstrated for many stable nuclei in the latter half of the 20th century, actualization of electron scattering for the unstable nuclei has been long awaited. Recently, we have performed a series of elastic electron scattering experiments with

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

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Commissioning of the Rare-RI Ring at RIKEN RI Beam Factory

Xe target. The high luminosity of around 10

Performance of a Resonant Schottky Pick-up in the Commissioning of Rare-RI Ring

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SCRIT Electron Scattering Facility — Present Status and Physics Program —

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Present status of Rare-RI Ring project in RIKEN RI Beam Factory

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A Novel Radioactive Isotope Ion Target SCRIT

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