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
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 Zr to the first excited state of Mo
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 Zr to the excited state of
Mo at 871.1 keV is studied using a low background 230 cm 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 to the excited state of is y at 90% C.L., an improvement by a factor of
4 over the existing experimental limit at 90\% C.L. The sensitivity is
estimated to be 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
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 gd and one
above 1 MeV resulting in 532 gd. No signals were observed in all
channels under investigation. New improved limits for the neutrinoless double
beta decay of Zn70 of (90% CL), the longest
standing limit of all double beta isotopes, and 0EC of Te120 of
(90% CL) are given. For the first time a
limit on the half-life of the 2ECEC of Te of (90% CL) is obtained. In addition, limits on 2ECEC 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
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
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 Xe. The sensitivities of the different proposals are
reviewed.Comment: 8 pages, prepared for TAUP 201
Searches for neutrinoless double beta decay
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 Xe. The sensitivities of the different proposals are
reviewed.Comment: 8 pages, prepared for TAUP 201
Searches for neutrinoless double beta decay
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 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
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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