[en] The β⁺/EC decays of ¹⁸³Hg and ¹⁸³Au have been studied on-line with mass-separated sources from the ISOCELE facility. A conversion-electron measurement was performed by means of a 180⁰ spectrograph and abnormally converted transitions were found. Level schemes of ¹⁸³Au and ¹⁸³Pt have been established. The isomeric state of ¹⁸³Pt has been located at 34.6 keV with respect to the ground state. A prolate shape for ¹⁸³Pt can be deduced from these results and for the first time there is good evidence to believe that the positive-parity states in odd-A gold isotopes correspond to oblate-shaped nuclei. The existence of a high-spin isomeric state in ¹⁸³Hg is discussed. (orig.)

[en] The decay of ¹⁸¹Au (T_1/2 = 11.4s) has been investigated using mass-separated radioactive sources produced by the ISOCELE facility. Level schemes of ¹⁷⁷Ir, ¹⁸¹Ir and ¹⁸¹Pt have been obtained. Most of the levels located at low excitation energy in ¹⁸¹Ir and ¹⁸¹Pt are identified as states corresponding to prolate-shaped nuclei. However the highly-converted transitions observed in ¹⁸¹Pt could indicate a new region of shape transition in the very neutron-deficient platinum isotopes (data, 13 figs., 6 tabs)

[en] The βsup(+)/EC decay of sup(181,183,185)Au was studied with mass-separated sources from the Isocele facility. These studies are the first step of a systematic approach to the neutron-deficient platinum nuclei. The stability of the 1/2 - [521] band through the sup(177-185)Pt isotopes is pointed out. (author)

[en] The decay of ¹⁸¹Au (T_1/2=11.4 s) has been investigated using mass-separated radioactive sources produced by the ISOCELE facility. Level schemes of ¹⁷⁷Ir, ¹⁸¹Ir and ¹⁸¹Pt have been obtained. Most of the levels located at low excitation energy in ¹⁸¹Ir and ¹⁸¹Pt are identified as states corresponding to prolate-shaped nuclei. Numerous highly converted transitions have been found in ¹⁸¹Pt. (orig.)

[en] In the present paper we stress on the characteristics of the longlived isomeric states we have established in ¹⁸⁵Hg, ¹⁸³Pt and ¹⁸⁵Pt. A brief description of the experimental techniques are given and some interpretations are presented. (orig./HSI)