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[en] Many of us grew up being taught that the standard atomic weights we found in the back of our chemistry textbooks or on the Periodic Table of the Chemical Elements hanging on the wall of our chemistry classroom are constants of nature. This was common knowledge for more than a century and a half, but not anymore. The following text explains how advances in chemical instrumentation and isotopic analysis has changed the way we view atomic weights and why they are no longer constants of nature.
[en] An attempt has been made to establish a simple rule by which one can calculate the value of the mass number of the stable isotope of an element with a fair degree of accuracy. The rule is expressed by the relation: X=2Z+number of d and f electrons, where X=mass number, Z=atomic or protonic number of the element in question. Some more relations are also obtained for ranges of atomic number. It is claimed that they give more accurate mass numbers. (M.G.B.)
[en] We construct effective 2- and 3-body Hamiltonians for the p-shell by performing 12(hbar)(Omega) ab initio no-core shell model (NCSM) calculations for A=6 and 7 nuclei and explicitly projecting the many-body Hamiltonians onto the 0(hbar)(Omega) space. We then separate these effective Hamiltonians into 0-, 1- and 2-body contributions (also 3-body for A=7) and analyze the systematic behavior of these different parts as a function of the mass number A and size of the NCSM basis space. The role of effective 3- and higher-body interactions for A > 6 is investigated and discussed
[en] The centre at the Institute for Nuclear Research (MTA Atomki) consists of two evaluators who devote altogether 0.5 FTE to mass-chain evaluation work. We have been working on mass-chain evaluations since 2009, and our permanent responsibilities are A=101-105. Our evaluation work is currently supported non-financially by MTA Atomki.
[en] Recently, the first nuclei to lie along an arc of regularity in the collective symmetry triangle were identified. These nuclei are predicted to display significantly more ordered spectra than their neighbors. The nuclei identified all lie in the rare earth region from A=156-180. Here we present the results of a search of all known nuclei from A=90-208 and have identified an additional set of such candidates for regular nuclei using a particular degeneracy condition as a signature