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[en] The Ag isotopes demonstrate a rich diversity of structure phenomena. These can be linked to the single particle configurations and the collective rotation of a tri-axial core. The presentation will cover the experimental evidences which have been established using the heavy ion beams from the Pelletron accelerators at Mumbai and Delhi and comparisons with different nuclear structure models
[en] The so-called signature inversion has recently attracted a lot of attention both in experimental and theoretical aspects. In order to gather more information about this phenomenon in new mass regions the πg9/2νh11/2 and πg9/2ν(h11/2)2 bands were studied in the A ∼ 100 nuclei. It has been revealed that signature inversion systematically occurs in these bands. Two types of signature inversion have been observed in this region. (R.P.)
[en] The silver nuclei are placed in the verge between the classical shell model and collective nuclear regions. As such, properties often attributed to one or another mode are observed to co-exist at low excitation energies. Of particular interest is the competition between the π g9/2-3 configuration and the core excitations, which has been challenging for a number of theoretical models to describe. This work presents a systematical study of low-lying excited states in the silver nuclei. A correlation between the (j,j-1) energy gap and the core's 2+ level energy is observed, which seems to be coherent, to certain extent, with both the particle-core coupling and the shell model approaches.
[en] Full text: The fission process produces neutron-rich nuclides far from stability with comparable excitation energy and relatively high angular momentum. Therefore it is used as an important tool to study the variety of different nuclear structures . The collective band around neutron-rich Ag isotopes have configuration of two intruder orbitals πg9/2n * νh11/2m which presents triaxiality [2, 3]. The interpretations of these nuclei towards the mid-shell were usually carried out by the deformed basis collective shell models assuming deformation in the core and few quasi particles. The view from large-scale shell model with spherical basis could bring new perspective in this region, such as unexpected breaking of natural seniority in In arising from proton neutron interaction . The 113-121Ag isotopes which lie at the borderline of spherical and deformed basis shell model calculations were studied by exploiting the prompt γ-ray spectroscopy of the isotopically identified fission fragments using the VAMOS++ spectrometer and the EXOGAM Ge-array at GANIL . Low-lying high-spin states of neutron-rich 113,118-121Ag have been established for the first time . The excited states of both odd-A and even-A isotopes followed the smooth systematics of those in Cd core. A large signature splitting in odd-A isotopes and a signature inversion in even-A isotopes, which is often used as a finger print of triaxial deformation, through out long chain of isotopes in 50 < N < 82 region, is striking. The large-scale shell model calculations reproduce the experimental spectra and the signature splitting, revealing their microscopic nature. The natural seniority ordering was broken more severely than In isotopes  inducing strong mixed wave functions. The main features of signature splitting are reproduced by crude shell model including only πg9/2 and νh11/2, indicating the yrast band in the Ag isotopes can be essentially understood based on πg9/2n * νh11/2m multiplet, without any particular assumption about the deformation. This simplicity behind the complex structures in the wave function could be owing to the strong contribution from both proton and neutron intruder orbitals with unique parity, which makes the configuration of the band fairly pure. Perspectives of the recent experiment with VAMOS++ and AGATA γ-ray tracking detectors will be discussed.
[en] Massive radionuclides were released into the environment due to the Fukushima Daiichi nuclear power plant (FDNPP) accident in March 2011. The concentrations of Pu and 110mAg in a soil sample that was collected in Futaba-machi located at 4 km north-west of FDNPP were measured by α-spectrometry and γ-spectrometry, respectively. The analytical result suggests that Pu isotopes are deposited in the soil as particles with high radioactivity (hot particles), although the 110mAg isotope is deposited uniformly like as Cs isotopes in a soil sample. (author)