35 research outputs found
Results of a search for monopoles and tachyons in horizontal cosmic ray flux
A search for monopoles and tachyons at ground level was carried out using an arrangement consisting of an ionization calorimeter and two hodoscope detectors. No clear evidence for these particles was obtained. The flux of monopoles with velocities beta approximately 0.01 is found to be less than 5.1 x 10 to the minus 13th power square centimeters s(-1) sr(-1) (95% cl.). The upper limit on the tachyon flux density is set as a 6 x 10 the minus 9th power particle/square centimeter event
Energy spectrum of cascade showers induced by cosmic ray muons in the range from 50 GeV to 5 TeV
The energy spectrum of cascade showers induced by electromagnetic interactions of high energy muons of horizontal cosmic ray flux in iron absorber was measured. The total observation time exceeded 22,000 hours. Both the energy spectrum and angular distributions of cascade showers are fairly described in terms of the usual muon generation processes, with a single power index of the parent meson spectrum over the muon energy range from 150 GeV to 5 TeV
Study of 2b-decay of Mo-100 and Se-82 using the NEMO3 detector
After analysis of 5797 h of data from the detector NEMO3, new limits on
neutrinoless double beta decay of Mo-100 (T_{1/2} > 3.1 10^{23} y, 90% CL) and
Se-82 (T_{1/2} > 1.4 10^{23} y, 90% CL) have been obtained. The corresponding
limits on the effective majorana neutrino mass are: m < (0.8-1.2) eV and m <
(1.5-3.1) eV, respectively. Also the limits on double-beta decay with Majoron
emission are: T_{1/2} > 1.4 10^{22} y (90% CL) for Mo-100 and T_{1/2}> 1.2
10^{22} y (90%CL) for Se-82. Corresponding bounds on the Majoron-neutrino
coupling constant are g < (0.5-0.9) 10^{-4} and < (0.7-1.6) 10^{-4}.
Two-neutrino 2b-decay half-lives have been measured with a high accuracy,
T_{1/2} Mo-100 = [7.68 +- 0.02(stat) +- 0.54(syst) ] 10^{18} y and T_{1/2}
Se-82 = [10.3 +- 0.3(stat) +- 0.7(syst) ] 10^{19} y.Comment: 5 pages, 4 figure
Recent advances in neutrinoless double beta decay search
Even after the discovery of neutrino flavour oscillations, based on data from
atmospheric, solar, reactor, and accelerator experiments, many characteristics
of the neutrino remain unknown. Only the neutrino square-mass differences and
the mixing angle values have been estimated, while the value of each mass
eigenstate still hasn't. Its nature (massive Majorana or Dirac particle) is
still escaping. Neutrinoless double beta decay (-DBD) experimental
discovery could be the ultimate answer to some delicate questions of elementary
particle and nuclear physics. The Majorana description of neutrinos allows the
-DBD process, and consequently either a mass value could be measured or
the existence of physics beyond the standard should be confirmed without any
doubt. As expected, the -DBD measurement is a very difficult field of
application for experimentalists. In this paper, after a short summary of the
latest results in neutrino physics, the experimental status, the R&D projects,
and perspectives in -DBD sector are reviewed.Comment: 36 pages, 7 figures, To be publish in Czech Journal of Physic
ИССЛЕДОВАНИЯ БИОЛОГИЧЕСКИХ ОБЪЕКТОВ НА КЛЕТОЧНОМ И СУБКЛЕТОЧНОМ УРОВНЕ С ПОМОЩЬЮ ФЕМТОСЕКУНДНОГО ЛАЗЕРНОГО ОПТИЧЕСКОГО ПИНЦЕТА-СКАЛЬПЕЛЯ
The aim of this work was developing of elements of the precise three-dimensional positioning technology of one or several micron and submicron size biological objects. Thereto a laboratory unit of hardware-software complex of optical femtosecond laser tweezers-scalpel was developed and constructed in the Joint institute for high temperatures RAS using material resources of Russia. Experimental data concerning a maximal manipulation speed of CHO and cells, produced from mammalian spinal ganglia (using protocols for producing pure culture of Schwann cells) was received. Besides facts of interaction of laser radiation with intracellular structures that lead to unexpected behavior of cell in the zone of optical trap and change of maximal speed of cell manipulation were determined. Целью данной работы является разработка элементов технологии прецизионного трехмерного позицио- нирования одного или нескольких биологических объектов микронного и субмикронного размеров. Для этого в Объединенном институте высоких температур РАН разработан и изготовлен лабораторный обра- зец программно-аппаратного комплекса оптического фемтосекундного лазерного пинцета-скальпеля на основе приборной базы, производимой в России. Получены экспериментальные результаты о максималь- ной скорости манипулирования CHO и клетками культуры, полученной из спинального ганглия млекопи- тающего (по протоколам получения очищенных культур шванновских клеток), а также о взаимодействии излучения с внутриклеточными структурами, которое приводит к изменению предполагаемого поведе- ния клетки в области оптической ловушки и максимальной скорости манипулирования последней.