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The article presents results of comparative tests for the determination of deuterium fluxes permeating through walls of austenitic stainless steel AISI304 (DIN 1.4301) chamber and Al{sub 2}O{sub 3} based ceramic F99.7 chamber. Both chambers represent a piece of φ(ext)=26*φ(int)=22*117 mm{sup 3} tube with spherical bottom ending. It is shown that at 773 K and deuterium pressure of 1200 mbar the permeated deuterium flux through the stainless steel chamber constituted 8*10{sup -5} cm{sup 3}/s, while the flux through ceramic one it did not exceed the sensitivity of the measurement method threshold, namely about 1.5*10{sup -7} cm{sup 3}/s. The ceramic chamber turned out to survive more than 10{sup 3} cycles of heating up to 773 K with no damages. It did not lose its tightness up to 10 bar of internal deuterium pressure. The authors also present test results of a prototype bed for reversible tritium storage. The bed's case was made of alumina based ceramic F99.7, titanium being used as tritide making metal and high frequency induction used for heating the tritide metal. (authors)

The low-lying spectra of 8He and 10He nuclei were studied in the 3H(6He, p)8He and 3H(8He, p)10He transfer reactions. The 0+ ground state (g.s.) of 8He and excited states, 2+ at 3.6–3.9 MeV and (1+) at 5.3–5.5 MeV, were populated with cross sections of 200, 100–250, and 90–125 μb/sr, respectively. Some evidence for a 8He state at about 7.5 MeV was obtained. We discuss a possible nature of the nearthreshold anomaly above 2.14 MeV in 8He and relate it to the population of a 1− continuum (soft dipole excitation) with a peak value at about 3 MeV. The lowest energy group of events in the 10He spectrum was observed at ∼ 3 MeV with a cross section of ∼ 140 μb/sr. We argue that this result is consistent with the previously reported observation of 10He providing the new 10He g.s. position at about 3 MeV

Automated system feeding into ion source hydrogen isotopes as molecules with preset ratio of the fluxes is described. The control system automatically maintained the working parameters and provided graphic and digital representation of the controlled processes. Theradio-frequency (RF) ion source installed at the axial injection line of the cyclotron produced ion beams of HD + , HT + , DT + , D 2 H + , etc. At a several months DT + beam acceleration the tritium consumption was less than 108 Bq/hr. The intensity of a 58.2 MeV triton beam (T + ions) extracted from the cyclotron chamber was about 10 nA.

The paper presents results of tritium-structural materials interaction modeling by simultaneous exposure to radiogenic helium-3 and hydrogen (both dissolved and external). This method of synergetic effect of radiogenic helium-3 and hydrogen is a radiation-safe technique to study the tritium impact on mechanical properties of structural materials. Applicability of the method is illustrated by technique and research results on the impact of high-pressure hydrogen (80MPa), helium-3 (concentration ∼140appm) and their synergetic (hydrogen+ 3 He) effecs on mechanical properties of CrNi40MoCuTiAl alloy in temperature range from 20 to 600°C. It has been shown that joint effect of radiogenic helium-3 and hydrogen on mechanical properties of alloy can not be represented as the result of a simple summation of helium and hydrogen embrittlement. Proposed technique of synergetic impact of radiogenic helium-3 and hydrogen allows more correct simulation and investigation in the tritium impact on mechanical properties of materials than individual research in helium or hydrogen embrittlement.

For the experiment on the measurement of the electron antineutrino magnetic moment we suggest a new approach to the tritium source design, namely, a configuration of annular cells filled with TiT{sub 2} that are stacked into a hollow cylinder. Detectors are mounted in the hole inside.We present results of the optimization of geometrical and physical parameters of the source with respect to its experimental effectiveness and safety guaranty at all stages of its lifecycle. We discuss the choice of the construction materials and specify technological issues relevant to radiation purity of the source, being of the special concern in the experiment on the electron antineutrino magnetic moment measurement.

The superpermeability phenomenon was suggested to use in fusion machines to separate the fuel mixture from helium ashes, to arrange in-vessel fuel recirculation contours and effective evacuation of...

To measure muon catalyzed fusion (MC) parameters in liquid tritium with the accuracy better than 10% in the reaction ttμ → 4 He + n +n+ μ, a cryogenic tritium target (CTT) of a 8.1 cm 3 volume was created. The CTT is a radiation-safe complex containing chemically bound tritium in the form of uranium tritide in a special source. In 2003, using the CTT, two runs of measurements with liquid tritium MC parameters were made on the synchrocyclotron muon channel in the Dzhelepov Laboratory of Nuclear Problems, Joint Institute for Nuclear Research (DLNP JINR).

The paper presents designs of a set of high-pressure targets developed by RFNC-VNIIEF and JINR collaboration to study muon-catalyzed fusion at high density of hydrogen isotopes in a wide temperature range. Designs, technical and operating characteristics of the targets and service results are described.In 1997-2002 these targets were used to measure basic characteristics of muon catalysis in pure deuterium, binary D/T mixture and triple H/D/T mixture as a function of density ([variant phi] = 0.2 - 1.2 LHD{sup *}), temperature (T = 20-800 K) and concentration of hydrogen isotopes in a mixture.

Low-energy spectra of the He-8,He-10 nuclei were investigated in the (t, p)-type reactions at small centre-of-mass angles using similar to 25AMeV beams of He-6 and He-8 nuclei. The 0(+) ground state (g.s.) of He-8 and excited states, 2(+) at 3.6-3.9MeV and (1(+)) at 5.3-5.5 MeV, were populated with cross-sections of 200, 100-250, and 90-125 mu b/sr, respectively. To account for a near-threshold anomaly observed in the He-8 spectrum the population of a 1(-) continuum (soft dipole excitation) was considered. The lowest-energy group of events in the He-10 spectrum was observed at similar to 3MeV with a cross-section of similar to 140 mu b/sr. This result is consistent with the previously reported observation of He-10 providing a new g.s. position for He-10 at about 3MeV.

The nuclear system {sup 5}H was studied using the {sup 3}H(t,p){sup 5}H transfer reaction at a laboratory energy of 57.7 MeV and small center of mass angles. The energy and angular correlations among the {sup 5}H decay fragments were obtained by complete kinematical reconstruction. A broad structure in the {sup 5}H missing mass spectrum above 2.5 MeV with a typical width of several MeV was identified as a mixture of 3/2{sup +} and 5/2{sup +} states. Analysis of interference patterns observed in the measured angular correlations disclosed the 1/2{sup +} ground state of {sup 5}H concealed in the smooth missing mass spectrum. The deduced values for the resonance energy and width are E{sub g.s.}{approx_equal}1.8 MeV and {gamma}{sub g.s.}{approx_equal}1.3 MeV. The estimated cross sections for population of the ground state and the doublet of excited states at {theta}{sub c.m.}=5 deg. are 150{+-}50 {mu}b/sr and 4.6{+-}2 mb/sr, respectively.

International audience; The $^{5}$H system was produced in the $^{3}$H(t, p) $^{5}$H reaction studied at small CM angles with a 58MeV tritium ion beam. High statistics data were used to reconstruct the energy and angular correlations between the $^{5}$H decay fragments. A broad structure in the $^{5}$H missing-mass spectrum showing up above 2.5MeV was identified as a mixture of the $3/2^+$ and $5/2^+$ states. The data also present an evidence that the $1/2^+$ ground state of $^{5}$H is located at about 2MeV. Then, the $^{5}$H and $^{5}$He systems were explored by means of transfer reactions occurring in the interactions of 132MeV $^{6}$He beam nuclei with deuterium. In the $^{2}$H( $^{6}$He, $^{3}$H) reaction a T = 3/2 isobaric analog state of $^{5}$H in $^{5}$He was observed at an excitation energy of 22.0±0.3MeV with a width of 2.5±0.3MeV.

The 5H system was produced in the 3H(t,p)5H reaction studied with a 58 MeV tritium beam at small c.m. angles. High statistics data were used to reconstruct the energy and angular correlations between the 5H decay fragments. A broad structure in the 5H missing mass spectrum showing up above 2.5 MeV was identified as a mixture of the 3/2+ and 5/2+ states. The data also present evidence that the 1/2+ ground state of 5H is located at about 2 MeV.

The experimental setup is put in operation designed to study the phenomenon of the superpermeation of hydrogen isotopes, including tritium, through metals and to demonstrate the possibility of membrane pumping. The permeation of atomic hydrogen through the niobium membrane was shown to occur in the superpermeation regime. For the first time superpermeation of tritium through a metallic membrane was experimentally observed. The possibility of effective pumping, compression and recuperation of hydrogen isotopes by means of superpermeable membrane was demonstrated.