352 research outputs found

    Feasibility study of the observation of the neutrino accompanied double beta-decay of Ge-76 to the 0+(1) excited state of Se-76 using segmented germanium detectors

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    Neutrino accompanied double beta-decay of Ge-76 can populate the ground state and the excited states of Se-76. While the decay to the ground state has been observed with a half-life of 1.74 +0.18 -0.16 10^21 years, decays to the excited states have not yet been observed. Nuclear matrix elements depend on details of the nuclear transitions. A measurement of the half-life of the transition considered here could help to reduce the uncertainties of the calculations of the nuclear matrix element for the neutrinoless double beta decay of Ge-76. This parameter relates the half-life of the process to the effective Majorana neutrino mass. The results of a feasibility study to detect the neutrino accompanied double beta-decay of Ge-76 to the excited states of Se-76 are presented in this paper. Segmented germanium detectors were assumed in this study. Such detectors, enriched in Ge-76 to a level of about 86%, will be deployed in the GERDA experiment located at the INFN Gran Sasso National Laboratory, Italy. It is shown that the decay of Ge-76 to the 1122 keV 0+ level of Se-76 can be observed in GERDA provided that the half-life of the process is in the range favoured by the present calculations which is 7.5 10^21 y to 3.1 10^23 y.Comment: 18 pages, 4 figures. Submitted to Nucl. Phys.

    New limit for the half-life of double beta decay of 94^{94}Zr to the first excited state of 94^{94}Mo

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    Neutrinoless Double Beta Decay is a phenomenon of fundamental interest in particle physics. The decay rates of double beta decay transitions to the excited states can provide input for Nuclear Transition Matrix Element calculations for the relevant two neutrino double beta decay process. It can be useful as supplementary information for the calculation of Nuclear Transition Matrix Element for the neutrinoless double beta decay process. In the present work, double beta decay of 94^{94}Zr to the 21+2^{+}_{1} excited state of 94^{94}Mo at 871.1 keV is studied using a low background \sim 230 cm3^3 HPGe detector. No evidence of this decay was found with a 232 g.y exposure of natural Zirconium. The lower half-life limit obtained for the double beta decay of 94Zr\rm^{94}Zr to the 21+2^{+}_{1} excited state of 94Mo\rm^{94}Mo is T1/2(0ν+2ν)>3.4×1019T_{1/2} (0\nu + 2\nu)> 3.4 \times 10^{19} y at 90% C.L., an improvement by a factor of \sim 4 over the existing experimental limit at 90\% C.L. The sensitivity is estimated to be T1/2(0ν+2ν)>2.0×1019T_{1/2} (0\nu + 2\nu) > 2.0\times10^{19} y at 90% C.L. using the Feldman-Cousins method.Comment: 11 pages, 7 figures, Accepted in Eur. Phys. J.

    A Search for various Double Beta Decay Modes of Cd, Te and Zn Isotopes

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    Various double beta decay modes of Cd, Zn and Te isotopes are explored with the help of CdTe and CdZnTe semiconductor detectors. The data set is splitted in an energy range below 1 MeV having a statistics of 134.5 g\cdotd and one above 1 MeV resulting in 532 g\cdotd. No signals were observed in all channels under investigation. New improved limits for the neutrinoless double beta decay of Zn70 of T1/2>1.31016yrsT_{1/2} > 1.3 \cdot 10^{16} yrs (90% CL), the longest standing limit of all double beta isotopes, and 0νβ+\nu\beta^+EC of Te120 of T1/2>2.21016yrsT_{1/2} > 2.2 \cdot 10^{16} yrs (90% CL) are given. For the first time a limit on the half-life of the 2ν\nuECEC of 120^{120}Te of T1/2>9.41015yrsT_{1/2} > 9.4 \cdot 10^{15} yrs (90% CL) is obtained. In addition, limits on 2ν\nuECEC for ground state transitions of Cd106, Cd108 and Zn64 are improved. The obtained results even under rough background conditions show the reliability of CdTe semiconductor detectors for rare nuclear decay searches.Comment: Extended introduction and summar

    Correlative Microscopy: A Potent Tool for Biomedicine

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    The correlative microscopy method based on a combination of optical and electronic techniques that is increasingly widely used now, has a number of limitations. Here, an alternative approach is considered that uses scanning probe microscopy (SPM) technique to get high-resolution and ultra-high-resolution data. SPM greatly increases the possibilities of collecting new information (on topological, morphological, electrical, magnetic etc. properties). To obtain three-dimensional distributions of different parameters of the sample, ultramicrotomography is used, which allows to scan the sample in steps of up to 20 nm. The principal advantage of the approach is that spectral data are used which due to the combination in near field microscopy can be gained with high and ultrahigh resolution. All above mentioned features are implemented in a single instrument, which allows to have 3-D data and their distributions at the same instrumental platform. A special feature of the approach is the possibility to use all the power of micro(nano)spectral methods. Therefore, it would be more correct to name the proposed approach ”Correlative microspectroscopy”. Keywords: correlative microscopy, correlative microspectroscopy, scanning near-ielf optical microscopy, ultramicrotomography, Raman, TER

    Searches for neutrinoless double beta decay

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    Neutrinoless double beta decay is a lepton number violating process whose observation would also establish that neutrinos are their own anti-particles. There are many experimental efforts with a variety of techniques. Some (EXO, Kamland-Zen, GERDA phase I and CANDLES) started take data in 2011 and EXO has reported the first measurement of the half life for the double beta decay with two neutrinos of 136^{136}Xe. The sensitivities of the different proposals are reviewed.Comment: 8 pages, prepared for TAUP 201

    Searches for neutrinoless double beta decay

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    Neutrinoless double beta decay is a lepton number violating process whose observation would also establish that neutrinos are their own anti-particles. There are many experimental efforts with a variety of techniques. Some (EXO, Kamland-Zen, GERDA phase I and CANDLES) started take data in 2011 and EXO has reported the first measurement of the half life for the double beta decay with two neutrinos of 136^{136}Xe. The sensitivities of the different proposals are reviewed.Comment: 8 pages, prepared for TAUP 201

    Searches for neutrinoless double beta decay

    Full text link
    Neutrinoless double beta decay is a lepton number violating process whose observation would also establish that neutrinos are their own anti-particles. There are many experimental efforts with a variety of techniques. Some (EXO, Kamland-Zen, GERDA phase I and CANDLES) started take data in 2011 and EXO has reported the first measurement of the half life for the double beta decay with two neutrinos of 136^{136}Xe. The sensitivities of the different proposals are reviewed.Comment: 8 pages, prepared for TAUP 201

    SPATIAL PLANNING OF LAND USE IN THE SCIENTIFIC RESEARCH SYSTEM OF THE NATIONAL ACADEMY OF AGRARIAN SCIENCES OF UKRAINE

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    The issue of spatial organization and interactions, the influence of spatial development processes of research land use in the NAAS system is investigated. The spatial development of multidimensional ecological-economic systems in modern conditions requires a new methodological substantiation of approaches to the synergetic study of the economics of scientific research as the interaction of microeconomic agents, regional, national and global interactions, including the study of various spatial forms of land-use organization of scientific institutions and enterprises as centers coordination and accumulation of environmental, economic and social relationships between individual economic entities, territorial associations or regions. It has been substantiated that, in the NAAS system, the effectiveness of the spatial economy of research land use is determined by the zonal, territorial, and intrafarm features of the organization of research land use. Also justified is the need to establish a differentiated mode of use, protection and reproduction of land (soil) and other natural resources in accordance with the functional zoning of research land use, in particular, the allocation of such zones: 1) the area of research fields; 2) the area of growing elite seeds and planting material of agricultural crops; 3) a zone of regulated use; 4) the zone of conservation of agro-soil, environmental, historical and cultural complexes and objects valuable for agrarian science; 5) economic zone
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