Technological coaxial plasma accelerator

Plasma sources for accelerators intended for separation processes and surface treatment have been investigated. The conditions for the choice of system parameters, as well as plasma flux, injection system, and power source have been discussed. These parameters have been obtained experimentally. A conclusion about the role of metal erosion products of the electrodes has also been drawn.Исследуются плазменные источники-ускорители для процессов сепарации и обработки поверхностей. Обсуждаются условия выбора параметров системы, плазменного потока, системы напуска газа, источника питания. Экспериментально получены их параметры. Сделан вывод о роли металлических продуктов эрозии электродов.Досліджуються плазмові джерела прискорювачів для процесів сепарації та обробки поверхонь. Обговорюються умови вибору параметрів системи, плазмового потоку, системи напуску газа, джерела живлення. Експериментально одержані їх параметри. Зроблені висновки щодо металевих продуктів ерозії електродів

Condensed matter and AdS/CFT

I review two classes of strong coupling problems in condensed matter physics, and describe insights gained by application of the AdS/CFT correspondence. The first class concerns non-zero temperature dynamics and transport in the vicinity of quantum critical points described by relativistic field theories. I describe how relativistic structures arise in models of physical interest, present results for their quantum critical crossover functions and magneto-thermoelectric hydrodynamics. The second class concerns symmetry breaking transitions of two-dimensional systems in the presence of gapless electronic excitations at isolated points or along lines (i.e. Fermi surfaces) in the Brillouin zone. I describe the scaling structure of a recent theory of the Ising-nematic transition in metals, and discuss its possible connection to theories of Fermi surfaces obtained from simple AdS duals.Comment: 39 pages, 12 figures; Lectures at the 5th Aegean summer school, "From gravity to thermal gauge theories: the AdS/CFT correspondence", and the De Sitter Lecture Series in Theoretical Physics 2009, University of Groninge

Search for α\alpha decay of naturally occurring osmium nuclides accompanied by γ\gamma quanta

International audienceA search for α decay of naturally occurring osmium isotopes to the lowest excited levels of daughter nuclei has been performed by using an ultra-low-background broad-energy germanium γ detector with a volume of 112 cm3 and an ultrapure osmium sample with a mass of 118 g at the Gran Sasso National Laboratory of the INFN (Italy). The isotopic composition of the osmium sample has been measured with high precision using negative thermal ionization mass spectrometry. After 15851 h of data taking with the γ detector, no effect has been detected, and lower limits on the α decays were set at level of limT1/2≈1015–1019 yr. The limits for the α decays of Os184 and Os186 to the first excited levels of daughter nuclei, T1/2(Os184)≥6.8×1015 yr and T1/2(Os186)≥3.3×1017 yr (at 90% C.L.), exceed the present theoretical estimates of the decays' half-lives. For Os189 and Os192 also decays to the ground states of the daughter nuclei were searched for due to the instability of the daughter nuclides relative to β decay

New experimental limits on double-beta decay of osmium

International audienceDouble-beta processes in 184Os and 192Os were searched for over 15 851 h at the Gran Sasso National Laboratory (LNGS) of the I.N.F.N. by using a 118 g ultra-pure osmium sample installed on the endcap of a 112 cm3 ultra-low-background broad-energy germanium detector. New limits on double-electron capture and electron capture with positron emission in 184Os were set at the level of lim T 1/2 ∼ 1016–1017 years. In particular the 2ν2K and 2ν KL decays of 184Os to the ground state of 184W are restricted as T 1/2 ⩾ 3.0 × 1016 years and T 1/2 ⩾ 2.0 × 1016 years, respectively. A lower limit on the half-life for the double-beta decay of 192Os to the first excited level of 192Pt was set as lim T 1/2 = 2.0 × 1020 years at 90% confidence leve

Search for 2-beta decays of 96^Ru and 104^Ru by ultralow-background HPGe gamma spectrometry at LNGS: Final Results

An experiment to search for double-β decay processes in 96Ru and 104Ru, which are accompanied by γ rays, has been realized in the underground Gran Sasso National Laboratories of the I.N.F.N. (Italy). Ruthenium samples with masses of ≈0.5–0.7 kg were measured with the help of ultralow-background high-purity Ge γ -ray spectrometry. After 2162 h of data taking the samples were deeply purified to reduce the internal contamination of 40K. The last part of the data has been accumulated over 5479 h. New improved half-life limits on 2β+/εβ+/2ε processes in 96Ru have been established on the level of 1020 yr, in particular for decays to the ground state of 96Mo: T 2ν2β+ 1/2 1.4 × 1020 yr, T 2νεβ+ 1/2 8.0 × 1019 yr, and T 0ν2K 1/2 1.0 × 1021 yr (all limits are at 90% C.L.). The resonant neutrinoless double-electron captures to the 2700.2 and 2712.7 keV excited states of 96Mo are restricted as T 0νKL 1/2 2.0 × 1020 yr and T 0ν2L 1/2 3.6 × 1020 yr, respectively. Various two-neutrino and neutrinoless 2β half-lives of 96Ru have been estimated in the framework of the quasiparticle random-phase approximation approach. In addition, the T1/2 limit for 0ν2β− transitions of 104Ru to the first excited state of 104Pd has been set as 6.5 × 1020 yr.peerReviewe