Half-lives, neutron emission probabilities and fission yields of neutron-rich rubidium isotopes in the mass regionA=96 toA=100

Abstract

Neutron-rich rubidium isotopes were produced by thermal-neutron induced fission of 235U and were isolated by surface ionization and mass separation. The new isotope (51 _+ 17)ms a~176 was identified. The half-lives of the rubidium isotopes with mass number A =96 to A = 100 were measured using neutron multiscaling or gamma multispectrum analysis. Measurements of the delayed-neutron emission probability P, of 99Rb and of the fission yields of 97Rb, 98Rb, and 99Rb were performed.

Structure in the beta strength function of very neutron-rich Rb-isotopes

“…2). The same effect was observed earlier for core-polarized states in [15,[24][25][26], the dashed lines connect values calculated by the gross theory [8], the full squares correspond to microscopic calculations the y-decay of isobaric analog states in Sc, V, Cu [22,23]. The effect is reproduced by the calculation (Fig.…”

Discovery of rubidium, strontium, molybdenum, and rhodium isotopes

“…This half-life of 100 Rb is included in the weighted average of the accepted value of 51 (8) ms. The observation of 100 Rb was independently reported less than a month later by Peuser et al [61].…”

Reevaluation of Independent Fission Yields in Thermal-Neutron Fission of 235U

“…The compilation in this work also includes the relative IFY data of some alkali (Rb and Cs) and alkaline-earth (Sr and Ba) fission products obtained by using the mass separators "ISOL-MAINZ" [11], "OSTIS" [10], and "SOUS" [12] facilities. The detection limit of IFY determined by this method is about 10" 6 atom/fission.…”

“…To reduce the complexity of the fit, either the σ(Α) or F or both was fixed for all mass chains A in many data analyses [7,[9][10][11]13], More recently, DICKENS and McCONNELL [23] also proposed a direct correlation between σ(Α) and Z p (A) to further reduce the number of fit parameters. Since more than 200 experimental IFY values are compiled in this work, the simplifications and assumptions used previously become unnecessary.…”

“…More recently, new IFY data in 23S U(n th , f) were published, including absolute low-yield data using radiochemical method [7][8][9], relative values of IFY of some alkali, alkaline-earth, and representative elements using on-line mass separation techniques [10][11][12][13], and partial yield of fractional IFY data using direct recoil mass separation method [14][15][16][17], Only some of these data have been compiled in the latest evaluations by MEEK and RIDER [6]; therefore, data newly released in a collective manner can provide a critical test of existing evaluation methods. The systematics of low-yield data, in particular, can provide modifications and steer the extrapolation to unknown regions.…”