Strongly Enhanced Low Energy Alpha-Particle Decay in Heavy Actinide Nuclei and Long-Lived Superdeformed and Hyperdeformed Isomeric States

Relatively low energy and very enhanced alpha-particle groups have been observed in various actinide fractions produced via secondary reactions in a CERN W target which had been irradiated with 24-GeV protons. In particular, 5.14, 5.27 and 5.53 MeV alpha-particle groups with corresponding half-lives of 3.8(+ -)1.0 y, 625(+ -)84 d and 26(+ -)7 d, have been seen in Bk, Es and Lr-No sources, respectively. The measured energies are a few MeV lower than the known g.s. to g.s. alpha-decays in the corresponding neutron-deficient actinide nuclei. The half-lives are 4 to 7 orders of magnitude shorter than expected from the systematics of alpha-particle decay in this region of nuclei. The deduced evaporation residue cross sections are in the mb region, about 4 orders of magnitude higher than expected. A consistent interpretation of the data is given in terms of production of long-lived isomeric states in the second and third wells of the potential-energy surfaces of the parent nuclei, which decay to the corresponding wells in the daughters. The possibility that the isomeric states in the third minimum are actually the true or very near the true ground states of the nuclei, and consequences regarding the production of the long-lived superheavy elements, are discussed.Comment: 27 pages including 8 figures and 4 table

UPON SOME PECULIARITIES OF STRUCTURE AND VASCULARIZATION OF SUPERFICIAL AND PROFOUND CRURAL VEINS

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CHARACTERISTIC FEATURES IN THE VASCULARIZATION OF THE WALL OF THE POPLITEAL VEIN

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Images of Roma through the language of Bulgarian state archives

This research has been carried out as part of the RomaInterbellum Project which studies the Roma civic emancipation between World War I and World War II. Trawling through the Bulgarian archival documents on Roma in this time period, a reader cannot help but begin to form a certain image about the Tsigani, the term with which Roma have been popularly referred to in the archives. Unsurprisingly, this image does not seem to differ much from the one of today—that of the uneducated, dirty, foreign, and that pose a threat not only to the prosperity and well-being of the Bulgarian population and culture at large but also to the state and the economy. The research is based on archived files, letters of complaints from Bulgarian citizens and other documents sourced from Bulgarian state archives. The article analyses the words and language employed in the archived documents, the connotations they bear and the images they build. It also tries to show how, in the interwar period, this dominant language was utilised by Roma individuals and leaders in order to react, counter and protect their image and future. More importantly, they sought ways to build a better integrated Roma society through the establishment of own organisations and associations. Understanding this historical narrative from the interwar period is essential in advancing knowledge of many major issues surrounding the Roma today, such as housing, health and their social inclusion.Publisher PDFPeer reviewe

New Outlook on the Possible Existence of Superheavy Elements in Nature

A consistent interpretation is given to some previously unexplained phenomena seen in nature in terms of the recently discovered long-lived high spin super- and hyper-deformed isomeric states. The Po halos seen in mica are interpreted as due to the existence of such isomeric states in corresponding Po or nearby nuclei which eventually decay by gamma- or beta-decay to the ground states of 210Po, 214Po and 218Po nuclei. The low-energy 4.5 MeV alpha-particle group observed in several minerals is interpreted as due to a very enhanced alpha transition from the third minimum of the potential-energy surface in a superheavy nucleus with atomic number Z=108 (Hs) and atomic mass number around 271 to the corresponding minimum in the daughter.Comment: 8 pages, 8 figures, 5 tables. Paper presented at VII Int. School-Seminar on Heavy Ion Physics, May 27 - June 1, 2002, Dubna, Russi

Analysis of Flat Coils’ System with Displaced Sensors for Eddy Current NDE of Ferromagnetic Metals

The existing theoretical models for the eddy current method [1–3] frequently cannot accommodate new developments, especially in terms of new coil designs. Among them is a use of flat coils with displaced exciting and sensor coils which already have found practical applications in some new eddy current instruments (4). It can also be useful for the eddy current testing of pipes in oil and gas wells in order to localize the area of inspection (Fig. 1)

INTERCELLULAR CONTACTS BETWEEN SMOOTH MUSCLE CELLS IN THE NEOINTIMA OF THE AUTOGENOUS REVERSED SAPHENOUS VEIN GRAFTS

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AGE PECULIARITIES OF NON MYOSIN AND MYOSIN ADENOSINE TRIPHOSPHATASE ACTIVITY OF RABBIT VENOUS WALL

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Exact Evolution Operator on Non-compact Group Manifolds

Free quantal motion on group manifolds is considered. The Hamiltonian is given by the Laplace -- Beltrami operator on the group manifold, and the purpose is to get the (Feynman's) evolution kernel. The spectral expansion, which produced a series of the representation characters for the evolution kernel in the compact case, does not exist for non-compact group, where the spectrum is not bounded. In this work real analytical groups are investigated, some of which are of interest for physics. An integral representation for the evolution operator is obtained in terms of the Green function, i.e. the solution to the Helmholz equation on the group manifold. The alternative series expressions for the evolution operator are reconstructed from the same integral representation, the spectral expansion (when exists) and the sum over classical paths. For non-compact groups, the latter can be interpreted as the (exact) semi-classical approximation, like in the compact case. The explicit form of the evolution operator is obtained for a number of non-compact groups.Comment: 32 pages, 5 postscript figures, LaTe