Investigation of203, 205Hg with the (d, p?) reaction ? Identification of thei 13/2 neutron hole state in205Hg

Abstract

Low lying levels in 2~and 2~were studied with the (d, p) deuteron break-up reaction at Ee = 14 and 18 MeV. Gamma-rays and conversion-electrons were measured in coincidence with protons. In addition delayed spectra were recorded with gs and ms beam pulsing. The i13/2 neutron hole state was identified in 2~and confirmed in 2~The known level structure of 2~ below 2 MeV is confirmed and extended. For 2~we observe the 7-decay of several levels below 1.5 MeV, which were previously known from transfer reactions.

Investigation of new neutron-rich gold isotopes203Au and205Au

“…3 the A=203 7-ray spectra are given in (a) total projection and (b) gated with 1 to 2 MeV /?--rays. We observed an agreement of our 7-ray energies, see Table 2, with the level energies from [5,7] and thus we could assign these activities to the decay of/~ Their half-life was measured to be T1/2--60 (6) s. This value is in contradiction to the earlier estimate of TU2 < 10 s [2]. We also performed a Q-value determination by the measurement of fl-spectra coincident with the y-rays 44, 51, 218, 318, and 369 keV, respectively.…”

“…2. The levels in 2~ are known from the reactions 2~ t) and 2~ [5,7]. We measured 7-rays in coincidence with/?-rays in the energy window 1 < E~ < 2 MeV (cf.…”

Metastable states from multinucleon excitations in Tl202 and Pb203

“…For comparison, the half-life of the I π = 19/2 + state in 201 Pb, also populated in this experiment, is illustrated; the extracted value of 3.3(3) ns from the present work is consistent with the previously reported one: 3.2(6) ns [40]. [9,33]. The increase in the 12 − energy from 202 Tl to 206 Tl may be understood in terms of the neutron Fermi level moving farther away from the i 13/2 orbital, a situation similar to that invoked in the case of the 7 + state.…”

“…Different energy scales are used for the two panels of the figure in order to account for the contribution of the h 11/2 proton in the Tl case. N = 121 201 Hg and 203 Pb, and N = 123 isotones 203 Hg and 205 Pb, respectively[9,33]. The increase in the 12 − energy from202 Tl to206 Tl may be understood in terms of the neutron Fermi level moving farther away from the i 13/2 orbital, a situation similar to that invoked in the case of the 7 + state.…”

“…The experiment using INGA was performed at the Inter-University Accelerator Centre (IUAC), New Delhi, India. Excited levels in 202 Tl were populated through the 198 Pt( 7 Li, 3n) fusion-evaporation reaction at incident energies of [31][32][33][34][35][36] MeV with the 7 Li beam obtained from the Pelletron accelerator. The 198 Pt target was isotopically enriched (≈92%) and had a thickness ≈10 mg/cm 2 .…”