0000000000006408
AUTHOR
D. Schardt
The new neutron-rich isotope183Lu
The new neutron-rich isotope183Lu was produced in multinucleon transfer reactions by irradiatingnatW/Ta targets with 11.7 MeV/u136Xe ions, and identified by mass separation and decay spectroscopy. The measured half-life of183Lu is 58±4 s. The properties of the excited states of183Hf are discussed.
Collinear laser spectroscopy on108g, 108m In using an ion source with bunched beam release
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.
In-beam tests of scintillating fibre detectors at MAMI and at GSI
The performance of scintillating fibre detectors was studied with electrons at the spectrometer facility of the Mainz microtron MAMI, as well as in a C-12 beam of 2 AGeV energy and in a beam of different particle species at GSI. Multi-anode photomultipliers were used to read out one or more bundles of 128 fibres each in different geometries. For electrons a time resolution of FWHM = 1 ns was measured in a single detector plane with a detection efficiency epsilon > 99%. A time resolution of 310 ps (FWHM) between two planes of fibres was achieved for carbon ions, leading to a FWHM = 220 ps for a single detector. The hit position residual was measured with a width of FWHM = 0.27 mm. The var…
The decay of 0.57 s114Cs
Fusion reactions between58Ni projectiles and58Ni target nuclei were used to produce114Cs activity, which was studied by on-line mass separation and decay spectroscopy. The obtained half-life of 0.57±0.02 s and the probability ratio of 44±3 between betadelayed proton and beta-delayed alpha emission represent data with improved precision. The absolute branching ratios for both particle decay modes were determined to be (7 ±2)×10−2 and (1.6±0.6)×10−3, respectively. These branching ratios and the shapes of particle spectra are discussed with reference to the statistical model calculations. Groundstate alpha decay of114Cs was observed with an alpha energy of 3,226±30 keV and a branching ratio of…
Nuclear moments and charge radii of107?111in determined by laser spectroscopy
Collinear fast beam laser spectroscopy has been used to measure the hyperfine structure and isotope shift in the atomic 5s 2 5p 2 P 3/2-5s 2 6s 2 S 1/2 transition (λ=451 nm) of107–111In. Secondary beams of neutron deficient indium isotopes were prepared at the GSI on-line mass separator following fusion evaporation reactions. Magnetic dipole moments and electric quadrupole moments have been determined. The isotope shifts are discussed in terms of the change of the mean square nuclear charge radii and compared with the droplet model predictions and the deformation values calculated from the quadrupole moments.
Intense beams of mass-separated, neutron-deficient indium, tin, thallium and lead isotopes
A discharge ion source of the FEBIAD-type that delivers intense beams of neutron-deficient isotopes of indium, tin, thallium and lead produced in heavy-ion-induced fusion reactions is described. After mass separation the isotopically pure beams with intensities of up to 3 × 107 ions/s were available for gamma and laser spectroscopy. This corresponds to an overall separation efficiency of about 30%.
Nuclear moments and charge radii of105, 106In
With high resolution collinear fast beam laser spectroscopy in the 451 nm-line of Indium nuclear moments and the change in the mean square radii of the nuclear charge distribution of105,106 In have been determined.