Search results for "Cyclotron"
showing 10 items of 320 documents
Investigation of the elastic and inelastic scattering of 4He from 11B in the energy range 29-50.5 MeV
2018
We have measured the angular distributions for the elastic and inelastic scattering of 4He from 11B in the isochronous cyclotron U-150 M INP RK. The extracted α-particles beam has been accelerated to energy 29 MeV and then directed to 11B target. The experimental results were analyzed within the framework of both the optical model using different complex potential and the double folding potential obtained with different density-dependent NN interactions which give the corresponding values of the nuclear incompressibility K in the Hartree-Fock calculation of nuclear matter.
The isomeric structure of132Pr
2012
The isomeric structure of the neutron deficient nucleus 132Pr, located in the rare-earth region of the nuclear chart, has been studied with the 98Mo(40Ar,5pn)132Pr reaction at beam energies of 150, 158 and 165 MeV. The experiment was performed at the University of Jyvaskyla, Finland where the 40Ar beam was accelerated onto the target by the K130 cyclotron. The JUROGAM II HPGe detector array was employed in conjunction with the RITU gas-filled recoil separator. The focal-plane chamber housed a multi wire proportional counter and a position-sensitive silicon strip detector used for the implantation and identification of recoiling nuclei. The recoil-isomer tagging technique was used to correla…
Effect of electron cyclotron resonance ion source frequency tuning on ion beam intensity and quality at Department of Physics, University of Jyväskyl…
2010
Ion beam intensity and quality have a crucial effect on the operation efficiency of the accelerator facilities. This paper presents the investigations on the ion beam intensity and quality after the mass separation performed with the Department of Physics, University of Jyvaskyla 14 GHz electron cyclotron resonance ion source by sweeping the microwave in the 14.05–14.13 GHz range. In many cases a clear variation in the ion beam intensity and quality as a function of the frequency was observed. The effect of frequency tuning increased with the charge state. In addition, clear changes in the beam structure seen with the beam viewer were observed. The results confirmed that frequency tuning ca…
Accurate mass determination of short-lived isotopes by a tandem Penning-trap mass spectrometer
1990
A mass spectrometer consisting of two Penning traps has been set up for short-lived isotopes at the on-line mass separator ISOLDE at CERN. The ion beam is collected and cooled in the first trap. After delivery to the second trap, high-accuracy direct mass measurements are made by determining the cyclotron frequency of the stored ions. Measurements have been performed for $^{118}--^{137}$Cs. A resolving power of over ${10}^{6}$ and an accuracy of 1.4\ifmmode\times\else\texttimes\fi{}${10}^{\mathrm{\ensuremath{-}}7}$ have been achieved, corresponding to about 20 keV.
Oscillations of ECR ion source beam current along the beam transport of the JYFL K-130 cyclotron
2013
A versatile measurement system has been developed to study the temporal characteristics of ion beams in millisecond time scale. The system is composed of data acquisition hardware and LabVIEW based measurement and analysis program. The measurement system and ion beam current oscillation results measured with a 14 GHz AECR-U type ion source at University of Jyv"askyl"a, Department of Physics (JYFL), are presented. It is shown that the ion beams exhibit periodic current fluctuations at frequencies from 100 Hz to 1.5 kHz with amplitudes ranging from 1 to 65 percent of the average beam current. It is argued that these oscillations originate from the ion source plasma since their characteristics…
Highly-charged ions in a penning trap: mass measurements, etc.
1991
The use of a Penning trap will start a new generation of precision experiments on highly charged ions. The long storage time of the ions in combination with a controlled confinement in a very small volume will enable accuracies in mass determination better than δm/m = 10-8.
Mass Determination of Francium and Radium Isotopes by a Penning Trap Mass Spectrometer
1992
Abstract A tandem Penning trap mass spectrometer is used for mass measurement of radioactive isotopes produced at the on-line isotope separator ISOLDE/CERN. The mass is determined directly and with high accuracy by measuring the cyclotron frequency of the stored ions. Measurements were performed on 209 210 211 212 221 222Fr and 226 230Ra. A resolving power of 5 × 105 was used and an accuracy of 1·8 × 10−7 has been achieved.
Generation of a DC Fiske current by coupling of Bloch and in-plane cyclotron oscillations in a semiconductor superlattice
2006
The coherent coupling between electron Bloch and in-plane cyclotron oscillations in semiconductor superlatices in tilted electric and magnetic fields induces a unidirectional quasi-DC current in analogy to the DC Fiske effect observed when a superconductor Josephson junction or a superfluid weak link is coupled to an electromagnetic respectively an acoustic resonator. In all cases, the coupling opens an elastic rectifying transport channel. We explore the effect for the case of a superlattice both experimentally and theoretically, and specifically address the influence of the coupling on the frequency of the magnetoBloch oscillations.
Direct determination of the mass of28Si as a contribution to a new definition of the kilogram
1993
The mass of 28Si has been determined to be m(28Si) = 27.976 926 57(30) u by comparing the cyclotron frequencies of the singly charged ions 12C+, 12C+3 and 28Si+ in a Penning trap mass spectrometer. The experimental technique and the setup are described. The obtained accuracy as well as possible improvements are discussed. Our measurements are related to current efforts to base the kilogram on atomic properties by using an almost perfect single crystal of silicon.
A semi-3D method of calculating the magnetic field in a conventional sector-focused cyclotron
1991
Abstract A semi-3D method to calculate the median plane magnetic field in a conventional sector-focused cyclotron was developed in order to avoid the need of model magnet studies in the design of the Jyvaskyla K130 cyclotron. The method gives reasonably good results especially at high fields. At low fields where the relative permeability of iron is high the field can be calculated assuming constant magnetic scalar potential on the iron surfaces and solving a three-dimensional Laplace equation. The field calculation methods will be described and the comparison of calculated and measured fields will be given.