Search results for "nuclear fusion"
showing 10 items of 437 documents
STUDY OF SHORT-LIVED SILVER ISOTOPES WITH A LASER ION-SOURCE
1995
A chemically selective laser ion source based on resonance ionization of atoms in a hot cavity has been applied for the study of short-lived silver isotopes at CERN/ ISOLDE. Silver atoms were ionized by two resonant excitations and final laser ionization into the continuum. Decay properties of the neutron-rich isotopes121–127Ag were studied with a neutron long-counter and aβ-detector.
Precision measurement of the conversion electron spectrum of 83mKr with a solenoid retarding spectrometer
1992
This paper reports on precision measurements of conversion lines in the decay of 83mKr with nuclear transition energies of 32.1 keV and 9.4 keV, respectively. The spectra were taken from a submonolayer surface of 83mKr frozen onto a cold backing, using the new Mainz solenoid retarding spectrometer. The high luminosity and resolution of this instrument enables the observation of all allowed conversion lines up to the N-shell and to fully separate the elastic component from inelastic satellites. The combined analysis of the data yields the transition energies Ey=32151.5±1.1 eV and 9405.9±0.8 eV, respectively. The experiment served also to pilot the application of this spectrometer to the ques…
Collinear laser spectroscopy on108g, 108m In using an ion source with bunched beam release
1986
The hyperfine structure and isotope shift of108gIn and108mIn have been investigated by means of collinear fast-beam laser spectroscopy in the resonance line atλ=451 nm. The indium isotopes were prepared at the GSI on-line mass separator following a fusion evaporation reaction. For the first time, a FEBIAD ion source with bunched release of indium was used. Magnetic dipole moments, electric quadrupole moments and isotope shifts were determined. The present results lead us to assign the spinI=2 to the108In (T 1/2=40 min) state. Spins and moments are discussed in the framework of thejj-coupling model.
Excitation energy dependence of fragment-mass distributions from fission of 180,190 Hg formed in fusion reactions of 36 Ar + 144,154 Sm
2015
Physics letters / B 748, 89 - 94 (2015). doi:10.1016/j.physletb.2015.06.068
Non-adiabatic treatment of fission mass distribution
1975
The influence of dynamical corrections to fission mass yields has been studied within the frame work of the macroscopic-microscopic approach and solving the time-dependent Schrodinger equation for the asymmetry degree of freedom, treating the fragment separation classically. The results indicate that the actual motion lies in between the adiabatic and sudden approximations. In particular the dynamic effects tend to increase considerably the probability for symmetric fission as compared to the static case.
Peculiarities in fragment mass distribution in the 238U + 40Ar (243 MeV) reaction
2001
A pronounced fine structure (FS) in the form of distinct peaks was observed in neutron gated mass spectra from the decay of the 278110 composite system produced in the reaction 238U + 40Ar (243 MeV) at an initial excitation energy E * > 70 MeV. The FS peaks are located in the vicinity of mass numbers 70-80, 100, and 130, which correspond to those of magic nuclei (clusters). In the data there is also evidence for a new type of decay -- collinear cluster tripartition of an excited nucleus.
Meson exchange and isobar current effects in nuclear photon scattering
1980
Explicit expressions of meson exchange and isobar current contributions to the nuclear two-photon amplitude are derived in the non-relativistic limit. In connection with this amplitude the requirement of gauge invariance on the photon scattering amplitude and on the nuclear electromagnetic interaction operator is discussed in detail.
Einzelnachweis von Elektronen (15 bis 50 keV) in Kernphotoplatten
1960
Nuclear track emulsions (Ilford G 5) were used for counting of single slow electrons. They had to be accelerated by high voltage of about 30 kV and were incident vertically. The pulsed electron-beam was measured in a cage, single pulses were shot on the emulsion. The developed plates were photographed under the microscope and the tracks counted on the enlarged copies. The results are: about 40% of incoming electrons can be found as tracks in the emulsions. This number varies between different emulsions (of same type G 5), within one plate the number of tracks is better proportional to the number of electrons than between different plates. With a counting resultx one may expect the true resu…
Evidence for molecular-cluster states in222Th
1983
The groundstate and a negative parity band of222Th have been observed in the208Pb (180, 4n)222Th reaction by conversion electron and γ-ray spectroscopy identifying the evaporation residues in a recoil separator. The de-excitation pattern is characterized by strong El transitions interconnecting the levels of alternating parity. The yrast levels may be interpreted as a molecularcluster band.
Helium burning of22Ne
1989
The22Ne(α, γ)26Mg and22Ne(α, n)25Mg reactions were investigated forE α(lab) from 0.71 to 2.25 MeV. Neon gas enriched to 99% in22Ne was recirculated in a differentially pumped gas target system of the extended type. Theγ-ray transitions were observed with Ge(Li) detectors and the neutrons with3He ionization chambers. A previously known resonance at ER(lab)=2.05 MeV was verified and 15 new resonances were found in the energy range covered, with the lowest at ER(lab)=0.83 MeV. Information on resonance energies, widths, strengths,γ-ray branching ratios, as well asJ π assignments, is reported. The energy range investigated corresponds to the important temperature range ofT 9 from 0.3 to 1.4 (109…