Search results for "Physics::Accelerator Physics"
showing 10 items of 1235 documents
Small angle scattering from oriented latent nuclear tracks
1984
Abstract Using X-ray and neutron small-angle scattering we studied the defects in mica created by irradiation with uranium ions delivered from the UNILAC accelerator at GSI (Darmstadt, Germany). The defects are regions of reduced density and are best described as cylinders with Gaussian radial density distribution. Scaling laws are given for the time development and the energy dependence of the track parameters.
A Møller polarimeter for CW and pulsed intermediate energy electron beams
1990
The Moller polarimeter was mainly designed for the cw electron beam of the Mainz microtron (MAMI). The described polarimeter covers an energy range between 25 and 185 MeV and can relatively simply be upgraded to the maximum MAMI energy of 840 MeV. The Moller-scattered electrons are momentum-analyzed in the defocusing plane of a quadrupole magnet and both Moller electrons can be detected in coincidence for symmetrical scattering with ⊖cm=90°. All polarization components of the electron beam can be measured by suitable choices of the orientation of the target polarization. For pulsed electron beams with a small duty factor and a high peak current the polarimeter can also be operated with sing…
Cooling of radioactive ions with the Penning trap REXTRAP
2005
Abstract Cooling of radioactive ion beams in a Penning trap is an essential component of the post-accelerator REX-ISOLDE at CERN. Prior to their charge-breeding and acceleration, ions from the on-line mass separator ISOLDE are accumulated, cooled and bunched with REXTRAP. This beam preparation provides short ion pulses with low emittance, key ingredient for a high efficiency of REX-ISOLDE. Two different cooling techniques have been investigated with REXTRAP. Both rely on the use of a buffer gas as the coolant but differ in the way the transversal compression of the stored ion cloud is achieved. Sideband cooling with a light buffer gas as coolant is the standard technique used at REXTRAP so …
A dedicated decay-spectroscopy station for the collinear resonance ionization experiment at ISOLDE
2013
A newdecay-spectroscopystation(DSS)has been developed to be coupled to the collinear resonance ionization spectroscopy (CRIS) beam line at CERN-ISOLDE. The system uses a rotatable wheel with ten 20 mg=cm2 carbon foils as beam implantation sites for the efficient measurement of charged decay products. Silicon detectors are placed on either side of the carbon foil in an optimal geometry to cover a large solid angle for detecting these charged particles. In addition to the silicon detectors at the on-beam axis position, a second pair of off-beam axis detectors are placed at the wheel position 108 deg. away, allowing longer-lived species to be studied. Up to three high purity germanium detector…
The ISOLDE Silicon Ball
2003
The development of new spectroscopy devices with the capability of detecting charged particles and precisely determining their energy, angular distribution and nature has become one of the requirements for the investigation of weakly bound nuclei close to the particle driplines. With this aim the ISOLDE Silicon Ball is under construction. It is a charged particle spectroscopy device allowing for the investigation of the exotic nuclei produced at ISOLDE and at other similar facilities. Very high geometrical efficiency and broad energy range coverage are required. In order to allow for particle identification the simultaneous use of the Time of Flight and Pulse Shape Discrimination techniques…
Performance of HPGe detectors in high magnetic field
2006
A new generation of high-resolution hypernuclear gamma$-spectroscopy experiments with high-purity germanium detectors (HPGe) are presently designed at the FINUDA spectrometer at DAPhiNE, the Frascati phi-factory, and at PANDA, the antiproton proton hadron spectrometer at the future FAIR facility. Both, the FINUDA and PANDA spectrometers are built around the target region covering a large solid angle. To maximise the detection efficiency the HPGe detectors have to be located near the target, and therefore they have to be operated in strong magnetic fields B ~ 1 T. The performance of HPGe detectors in such an environment has not been well investigated so far. In the present work VEGA and EURO…
Study of medium-spin states of neutron-rich 87, 89, 91Rb isotopes
2019
International audience; Excited states of the rubidium isotopes$_{37}^{87, 89, 91}$Rb have been studied at the INFN Legnaro National Laboratory. Measurements of the $\gamma$ -ray decay of fragments produced in binary grazing reactions resulting from the interaction of a beam of 530 MeV$^{96}$Zr ions with a$^{124}$Sn target have been complemented by studies of the $\gamma$ -ray decay of fission fragments produced in the interaction of a beam of 230 MeV$^{36}$S ions with a thick$^{176}$Yb target. The structure of the yrast states of$_{37}^{87, 89, 91}$Rb has been discussed within the context of spherical shell-model and cranked Nilsson-Strutinsky calculations.
Spectroscopy of the neutron-deficientN=50nucleusRh95
2014
The neutron-deficient semimagic (neutron number N = 50) Rh-95 nucleus has been produced at high spins using the projectile-target system Ca-40 + Ni-58 at 125 MeV beam energy. The gamma-decays of le ...
Nuclear spins, moments, and changes of the mean square charge radii of sup.(140-153)Eu
1985
The hyperfine structures and isotope shifts of 14 isotopes of Eu (Z=63) in the mass range 140≦A≦153, partly with isomeric states, have been measured in the atomic transitions at 4,594 A and 4,627 A, using the technique of collinear fast-beam laser spectroscopy at the ISOLDE facility at CERN. The nuclear spins, the magnetic dipole and electric quadrupole moments, and the changes in the mean square charge radii have been evaluated. These nuclear parameters clearly reflect the effects of theN=82 neutron-shell closure in the single-proton hole states with respect to the semi-magic gadolinium (Z=64), and theN=88−90 shape transition.
Continuous Stern–Gerlach effect and the magnetic moment of the antiproton
2004
Abstract The measurement of the magnetic moment (or g-factor ) of the antiproton and of the proton is a sensitive test of CPT invariance. We discuss the possibility of applying the continuous Stern–Gerlach effect to detect quantum jumps between the two spin states (spin up and spin down) of the antiproton. The measurement will be performed on a single antiproton stored in a Penning trap. The g -factor of the antiproton is determined by measuring its cyclotron frequency and its spin precession frequency in the magnetic field of the trap. With the double Penning trap method the g -factor of the antiproton can be determined with an accuracy of 1 ppb.