The decay of the isotopes176Ir and177Ir

Abstract

176A77tr were produced by, irradiation of 141pr with 4~ I~-delayed y-rays of 176"17qr were observed for the first time. From yy-coincidence data decay schemes could be constructed. A new half-life of 1771r was obtained yielding tl/2 = 30 ( 2 ) s. c~-branching ratios of 3.1 ( 6 ) % for 761r and 0.06(1)% for 1771r were measured.

Laser-assisted decay spectroscopy for the ground states of Au180,182

“…1(a)]. However, as this decay branch is small [b α ( 176 Ir) = 3.1(6)%] [21], its contribution is regarded as negligible in the branching ratio calculation for 180 Au. Figure 5 shows the background-subtracted singles γ -ray spectrum recorded by the LEGe detector.…”

“…and of low-energy excitations in α-decay daughter nuclide 176 Ir are not well established. Several β-γ decay studies of 176 Ir have been performed [21][22][23]. In particular, based on the predominant feeding of I π = 4 + and 6 + states in the β-decay daughter 176 Os, the study [21] proposed a most-likely spin-parity of I = (5 + ) for the 8(1) s ground state of 176 Ir, see the summary in NNDC [24]; the latter evaluation, however, refrains from providing the spin value for the g.s.…”

Beta-decays of172?175Ir neutron-deficient isotopes

“…By using systematics on heavier odd-A Os isotopes [16] in addition with the Nilsson diagrams [17] for a//2 deformation around 0.18 and 0.20, the weakly fed levels at 147.9, 285.2 and 295.5keV respectively, in lV3Os, (Fig. In practice, it appears that the 173Ir //decay strongly favors the 9/2 + state with no observable 7/2 + state feeding.…”

The decay of the isotopes179Ir and180Ir

“…The observation of 1791r and 18~ is part of the extended spectroscopic investi9ations of neutron deficient hafniumto-platinum isotopes [1][2][3][4][5][6]. For 1791r, only the [3 half-life is known from the analysis of the decrease of the dau9hter isotope lines [7].…”

“…Rotational bands of 179'18~ have been studied by means of in-beam experiments [9][10][11]. We used a He-jet and a tape transport system to move the activity into measurement position [1][2][3][4][5][6]. Tar9ets of 2.3mg/cm 2 148Nd (93.2% enriched) were irradiated by a ~50enA 36Ar beam with a primary ener9y of 240MeV.…”