0000000000909414
AUTHOR
P. O. Larsson
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%.
Intense mass-separated beams of halogens and beta-delayed neutron emission from heavy bromine isotopes
Improved production yields of short-lived halogens were obtained from a ThO2 target, irradiated with 600 MeV protons, in combination with a negative surface ionization source. Mass-separated samples were studied by decay spectroscopy. Production yields of radioactive isotopes of chlorine, bromine, iodine and astatine are presented. Half-lives and relative neutron emission probabilities were measured for the heavy bromine isotopes89−92Br. Normalizing to earlier publishedPn values for89Br, the results are:89Br (4.30±0.14s,P n =13.6±0.8%),90Br (1.92±0.06s,P n =24.8±1.5%),91Br (0.53 ±0.03 s,P n =30.1 ±2.1%), and92Br (0.31 ±0.02 s,P n =34.6±2.5%). Energy spectra ofβ-delayed neutrons were measure…