Very proton rich nuclei withN?82

Abstract

Postaccelerated 58Ni and 6~ beams from the Munich MP tandem have been used to study the compound reactions 58Ni---,93Nb, 92Mo, 94Mo and 6~The final nuclei 148Er, 15~ and 147Ho have been investigated with in-beam 7-spectroscopic methods, such as excitation functions, 77 coincidences, bunched-beam and pulsed-beam techniques. Level schemes of a48Er, 15~ and 147Ho have been established with the following level energies, spins, parities and half-lives:The level scheme of 15~ has been discussed in the framework of the seniority scheme. Perfect agreement with the experiment has been found for the predictions of this scheme for the half-lives of 10 + states in N = 82 isotones. This is the first nuclear region where the predictions of the seniority scheme have been observed without strong perturbation.

Level structure of 68 149 Er81 and high-spin isomerism in proton-richN=81, 82, 83 nuclei

“…Further, the three y-rays appeared in coincidence with Er K X-rays, establishing them as 149Er transitions. They are clearly identical with the v-rays tentatively assigned by Nolte et al [2] to the decay of an 149Er isomer with tl/2=2.5 +0.9 gs, although our measurements show that the half-life is significantly longer. Subsequently, more detailed measurements for 149Er were performed by bombarding a 1 mg/cm 2 92Mo foil with 255 MeV 6~ ions, the most favorable beam-energy for *49Er production.…”

Beta delayed proton emission from the 14s 21/2+ spin gap isomer in95Pd

“…In the present work we describe the 7 spectroscopic study of the 13 decay of this 95pd high-spin isomer and the successful search for 13 delayed proton emission from this isomer. First results of the 13 decay of 95pd have been briefly communicated in a letter [2] and a conference report [3].…”

Identification of high spin states in146Dy throughγ-recoil coincidences

“…Low lying (~rh~l/2) 10 + aligned states are observed in all even-even nuclei and are generally isomeric [1,2,3]. In the N=80 isotone 146Dy a 150 ms 10 + isomer was identified at 2.9 MeV [3].…”