Beta decay half-lives of neutron rich Ti–Co isotopes around

Low-energy structure of2766Co39and2768CoLiddick1, Abromeit2, Ayres3 et al. 2012Phys. Rev. C285291View full textAdd to dashboardCite

“…The beta-decay curve was fit with contributions from the decay of 66 Fe, 66 Co, and a constant background and shows the characteristic behavior expected when the daughter nucleus has a halflife that is shorter than the parent. The half-life of the daughter, 66 Co, was fixed in the fit at a value of 180 ms [9,27,28]. The resulting half-life extracted for 66 Fe was 351 (6) ms consistent with previously obtained literature values [9,29,30].…”

“…Radioactive ions from Sc to Ni were produced using the Coupled Cyclotron Facility at the National Superconducting Cyclotron Laboratory by impinging a 130 MeV/A 86 Kr primary beam onto a 9 Be target located at the object position of the A1900 fragment separator [23]. The fragmentation products were separated using the A1900 and a thin kapton wedge placed at the intermediate dispersive image of the separator.…”

“…Such behavior is not completely unexpected given the rapid development of collectivity in other regions with the addition or subtraction of a few nucleons [5,6]. Within the N =40 region, the influence of the neutron g 9/2 , and to a lesser extent the d 5/2 , singleparticle states on the development of collectivity has been explored theoretically [7][8][9][10] and compared to a wealth of experimental signatures in the 24 Cr, 25 Mn, 26 Fe, and 27 Co isotopic chains. The systematics of the E(2 + 1 ) states in both Fe and Cr isotopes do not display a peak at N = 40 [11,12] but monotonically decrease in energy starting at N = 36 and N = 32, respectively.…”

Analogous intruder behavior near Ni, Sn, and Pb isotopes

“…Without the γ-ray coincidence requirement, the 69 Co decay curve yields a half-life of 206 (20) ms. Previously reported 69 Co half-life values without the γ-ray coincidence include 229(24) [25], 220(20) [6], 170(30) [26], and 270(50) ms [27].…”

Low-energy level schemes of66,68Fe and inferred proton and neutron excitations acrossZ=28Liddick1, Abromeit2, Ayres3 et al. 2013Phys. Rev. C217126View full textAdd to dashboardCite

“…2. The half-life of the daughter, 66 Fe and granddaughter 66 Co were fixed at 351 ms [17,[26][27][28] and 180 ms [27,29,30] respectively. The errors on the daughter (6 ms) and granddaughter (10 ms) did not contribute significantly to the error of the extracted 66 Mn half-life.…”