Radiative and nonradiative lifetimes in excited states of Ar, Kr and Xe atoms in Ne matrix

International Nuclear Information System (INIS)

Hahn, U.; Schwentner, N.

1979-10-01

Synchrotron radiation with its intense continuum and its excellent time structure has been exploited for time resolved luminescence spectroscopy in the solid state. By selective excitation of n = 1, n' = 1 and n = 2 exciton states of Xe, Kr and Ar atoms in Ne matrix we were able to identify the emitting states involved. Lifetimes within the cascade of radiative and radiationless relaxation between excited states as well as the radiative lifetimes for transitions to the ground state have been derived from the decay curves. Energy positions and radiative lifetimes of the emitting states correspond quite well with those of the free atoms. Radiative and radiationless relaxation processes take place within the manifold of excited states of the guest atoms. The rate constants for radiationless decay confirm an energy gap law. The order of the radiationless processes reaches in some cases extremely high values. Selection rules for spin and angular momentum are essential to understand the observed radiationless transition rates. (orig.)

Energies, wavelengths, and transition probabilities for Ge-like Kr, Mo, Sn, and Xe ions

International Nuclear Information System (INIS)

Nagy, O.; El Sayed, Fatma

2012-01-01

Energy levels, wavelengths, transition probabilities, and oscillator strengths have been calculated for Ge-like Kr, Mo, Sn, and Xe ions among the fine-structure levels of terms belonging to the ([Ar] 3d 10 )4s 2 4p 2 , ([Ar] 3d 10 )4s 4p 3 , ([Ar] 3d 10 )4s 2 4p 4d, and ([Ar] 3d 10 )4p 4 configurations. The fully relativistic multiconfiguration Dirac–Fock method, taking both correlations within the n=4 complex and the quantum electrodynamic effects into account, have been used in the calculations. The results are compared with the available experimental and other theoretical results.

Static electric polarizabilities and first hyperpolarizabilities of molecular ions RgH + (Rg = He, Ne, Ar, Kr, Xe): ab initio study

Science.gov (United States)

Cukras, Janusz; Antušek, Andrej; Holka, Filip; Sadlej, Joanna

2009-06-01

Extensive ab initio calculations of static electric properties of molecular ions of general formula RgH + (Rg = He, Ne, Ar, Kr, Xe) involving the finite field method and coupled cluster CCSD(T) approach have been done. The relativistic effects were taken into account by Douglas-Kroll-Hess approximation. The numerical stability and reliability of calculated values have been tested using the systematic sequence of Dunning's cc-pVXZ-DK and ANO-RCC-VQZP basis sets. The influence of ZPE and pure vibrational contribution has been discussed. The component αzz has increasing trend in RgH + while the relativistic effect on αzz leads to a small increase of this molecular parameter.

Nature of the bonding in the AuNgX (Ng = Ar, Kr, Xe; X = F, Cl, Br, I) molecules. Topological study on electron density and the electron localization function (ELF).

Science.gov (United States)

Makarewicz, Emilia; Gordon, Agnieszka J; Berski, Slawomir

2015-03-19

Topological analysis of the electron localization function (ELF) has been carried out for the AuNgX (Ng = Ar, Kr, Xe; X = F, Cl, Br, I) molecules using the wave function approximated by the CCSD, MP2, and DFT(B3LYP, M062X) methods including zero-order regular approximation (ZORA). In the Ng-F bond, the bonding disynaptic attractor V(Ng,F) is missing; therefore, there are no signs of the covalent binding. The nature of the Au-Ng bond depends on the computational method used. Analysis of the ELF carried out for the AuArF and AuXeF molecules, with the wave function approximated by the CCSD and MP2 methods, shows the V(Au,Ng) attractor possibly corresponding to a partially covalent binding between the gold and noble gas atom. However, its very small basin population (<1e) and a very large value of the variance of the basin population suggest that the Au-Ng bond has a very delocalized character. Such bond nature may be related to the charge shift concept with a resonance of the Au(-+)NgX, Au(+-)NgX hybrids. The weakest Au-Ng bond, in terms of the smallest amount of electron density for the V(Au,Ng) basin, is found for the AuKrF molecule with the CCSD method (0.13e). The MP2 method, however, does not yield any V(Au, Ng) population; hence, the covalent Au-Kr bond is not confirmed. Because the V(Au,Ng) attractor is also not observed with the DFT method, the proper characterization of the Au-Ng bond requires proper description of correlation effects. Additional studies on the Au2 and [AuXe](+) molecules, performed at the CCSD and B3LYP levels, exhibit no V(Au,Au) and V(Au,Xe) bonding basins either.

Influence of Xe and Kr impurities on x-ray yield from debris-free plasma x-ray sources with an Ar supersonic gas jet irradiated by femtosecond near-infrared-wavelength laser pulses

Science.gov (United States)

Kantsyrev, V. L.; Schultz, K. A.; Shlyaptseva, V. V.; Petrov, G. M.; Safronova, A. S.; Petkov, E. E.; Moschella, J. J.; Shrestha, I.; Cline, W.; Wiewior, P.; Chalyy, O.

2016-11-01

Many aspects of physical phenomena occurring when an intense laser pulse with subpicosecond duration and an intensity of 1018-1019W /cm2 heats an underdense plasma in a supersonic clustered gas jet are studied to determine the relative contribution of thermal and nonthermal processes to soft- and hard-x-ray emission from debris-free plasmas. Experiments were performed at the University of Nevada, Reno (UNR) Leopard laser operated with a 15-J, 350-fs pulse and different pulse contrasts (107 or 105). The supersonic linear (elongated) nozzle generated Xe cluster-monomer gas jets as well as jets with Kr-Ar or Xe-Kr-Ar mixtures with densities of 1018-1019cm-3 . Prior to laser heating experiments, all jets were probed with optical interferometry and Rayleigh scattering to measure jet density and cluster distribution parameters. The supersonic linear jet provides the capability to study the anisotropy of x-ray yield from laser plasma and also laser beam self-focusing in plasma, which leads to efficient x-ray generation. Plasma diagnostics included x-ray diodes, pinhole cameras, and spectrometers. Jet signatures of x-ray emission from pure Xe gas, as well as from a mixture with Ar and Kr, was found to be very different. The most intense x-ray emission in the 1-9 KeV spectral region was observed from gas mixtures rather than pure Xe. Also, this x-ray emission was strongly anisotropic with respect to the direction of laser beam polarization. Non-local thermodynamic equilibrium (Non-LTE) models have been implemented to analyze the x-ray spectra to determine the plasma temperature and election density. Evidence of electron beam generation in the supersonic jet plasma was found. The influence of the subpicosecond laser pulse contrast (a ratio between the laser peak intensity and pedestal pulse intensity) on the jets' x-ray emission characteristics is discussed. Surprisingly, it was found that the x-ray yield was not sensitive to the prepulse contrast ratio.

Multiple photoionization from 3p excitation of Kr and 4p excitation of Xe

International Nuclear Information System (INIS)

Hayaishi, T.

1986-01-01

The photoionization cross sections for multiply charged ions produced by 3p excitation of Kr and 4p excitation of Xe have been obtained by means of a time-of-flight mass spectrometer and synchrotron radiation. It is found that the main formation of doubly to quadruply charged ions in both Kr and Xe is caused from the each initial p-hole state through a Coster-Kronig transition followed by Auger of double Auger processes. The formation of singly charged ions in these excitation energy regions is caused by direct photoionization from outermost shell electrons in both Kr and Xe. Triply charged ions are prominently produced among the multiply charged ions. The quadruple photoionization cross sections show clearly the structures due to the Rydberg series, 3p -1 nl of Kr and 4p -1 nl of Xe. Their main structures were assigned to the 3p -1 nd series in Kr and the 4p -1 nd series in Xe. (orig.)

Theoretical treatment of the spin-orbit coupling in the rare gas oxides NeO, ArO, KrO, and XeO

Science.gov (United States)

Langhoff, S. R.

1980-01-01

Off-diagonal spin-orbit matrix elements are calculated as a function of internuclear distance for the rare gas oxides NeO, ArO, KrO, and XeO using the full microscopic spin-orbit Hamiltonian, including all one- and two-electron integrals, and POL-CI wave functions comparable to those of Dunning and Hay (1977). A good agreement was found when comparing these results in detail with the calculations of Cohen, Wadt and Hay (1979) that utilize an effective one-electron one-center spin-orbit operator. For the rare gas oxide molecules, it is suggested that the numerical results are a more sensitive test of the wave functions (particularly to the extent of charge transfer) than the exact evaluation of all terms in the full spin-orbit operator.

Hg-Xe exciplex formation in mixed Xe/Ar matrices: molecular dynamics and luminescence study.

Science.gov (United States)

Lozada-García, Rolando; Rojas-Lorenzo, Germán; Crépin, Claudine; Ryan, Maryanne; McCaffrey, John G

2015-03-19

Luminescence of Hg((3)P1) atoms trapped in mixed Ar/Xe matrices containing a small amount of Xe is reported. Broad emission bands, strongly red-shifted from absorption are recorded which are assigned to strong complexes formed between the excited mercury Hg* and xenon atoms. Molecular dynamics calculations are performed on simulated Xe/Ar samples doped with Hg to follow the behavior of Hg* in the mixed rare gas matrices leading to exciplex formation. The role of Xe atoms in the first solvation shell (SS1) around Hg was investigated in detail, revealing the formation of two kinds of triatomic exciplexes; namely, Xe-Hg*-Xe and Ar-Hg*-Xe. The first species exists only when two xenon atoms are present in SS1 with specific geometries allowing the formation of a linear or quasi-linear exciplex. In the other geometries, or in the presence of only one Xe in SS1, a linear Ar-Hg*-Xe exciplex is formed. The two kinds of exciplexes have different emission bands, the most red-shifted being that involving two Xe atoms, whose emission is very close to that observed in pure Xe matrices. Simulations give a direct access to the analysis of the experimental absorption, emission, and excitation spectra, together with the dynamics of exciplexes formation.

Single electron capture in N^+ -(Ne, Kr, Xe) collisions

Science.gov (United States)

Reyes, Pedro G.; Castillo, Fermin; Martinez, Horacio

2001-05-01

Total cross sections for single electron capture of N^+ ions impinging on Ne, Kr and Xe were measured in the energy range of 1.5 to 5.0 keV. The electron capture cross sections for all the targets studied are found to be in excellent agreement with previous data in the low-energy range. The present data together with previous measurements give a general shape of the whole curve of single electron capture cross sections for the N^+ - Ne system. For the cases of N^+ - (Kr, Xe) systems, semiempirical calculation using the two-state approximation are in very good agreement with present cross sections data. Research supported by DGAPA IN-100392 and CONACyT 32175-E

Independent yields of Kr and Xe isotopes for the photofission of heavy nuclei

CERN Document Server

Gangrskij, Y P; Mishinskij, G V; Penionzhkevich, Yu E; Szoelloes, O; Zhemenik, V I

2002-01-01

Presented are the yields of primary fission fragments (produced in the process of the rupture of the nucleus) of Kr (A = 87- 93) and Xe (A 148-143) for the photofission of sup 2 sup 3 sup 2 Th, sup 2 sup 3 sup 8 U and sup 2 sup 4 sup 4 Pu, which were measured using Bremsstrahlung from a microtron, the energy of accelerated electrons being 25 MeV. A technique was used that includes transportation of fragments escaped from the target with a gas flow through a capillary and the condensation of Kr and Xe inert gases in a cryostat at the temperature of liquid nitrogen. Fragments of all the other elements were retained with a filter at the entrance of the capillary. Kr and Xe isotopes were identified by the gamma spectra of their daughter products. The mass number distributions are obtained of the independent yields of Kr and Xe isotopes, which are compared with the similar characteristics for the fission induced by thermal and fast neutrons; the charge shifts for the fragments under study relative to the unchanged...

Independent Yields of Kr and Xe Isotopes for the Photofission of Heavy Nuclei

CERN Document Server

Gangrsky, Yu P; Maslova, N Yu; Penionzhkevich, Yu E; Szöllös, O; Zhemenik, V I

2002-01-01

Presented are the yields of primary fission fragments (produced in the process of the rupture of the nucleus) of Kr (A=87-93) and Xe (A=148-143) for the photofission of ^{232}Th, ^{238}U and ^{244}Pu, which were measured using bremsstrahlung from a microtron, the energy of accelerated electrons being 25 MeV. A technique was used that includes transportation of fragments escaped from the target with a gas flow through a capillary and the condensation of Kr and Xe inert gases in a cryostat at the temperature of liquid nitrogen. Fragments of all the other elements were retained with a filter at the entrance of capillary. Kr and Xe isotopes were identified by the gamma-spectra of their daughter products. The mass number distributions are obtained of the independent yields of Kr and Xe isotopes, which are compared with the similar characteristics for the fission induced by thermal and fast neutrons; the charge shifts for the fragments under study relative to the unchanged charge distribution are determined. The pe...

Independent yields of Kr and Xe isotopes in the photofission of heavy nuclei

International Nuclear Information System (INIS)

Gangrsky, Yu.P.; Zhemenik, V.I.; Maslova, N.Yu.; Mishinsky, G.V.; Penionzhkevich, Yu.E.; Szoelloes, O.

2003-01-01

The yields of Kr (A = 87-93) and Xe (A = 138-143) primary fission fragments produced in 232 Th, 238 U, and 244 Pu photofission upon the scission of a target nucleus and neutron emission were measured in an experiment with bremsstrahlung from electrons accelerated to 25 MeV by a microtron, and the results of these measurements are presented. The experimental procedure used involved the transportation of fragments that escaped from the target by a gas flow through a capillary and the condensation of Kr and Xe inert gases in a cryostat at liquid-nitrogen temperature. The fragments of all other elements were retained with a filter at the capillary inlet. The isotopes of Kr and Xe were identified by the γ spectra of their daughter products. The mass-number distributions of the independent yields of Kr and Xe isotopes are obtained and compared with similar data on fission induced by thermal and fast neutrons; the shifts of the fragment charges with respect to the undistorted charge distribution are determined. Prospects for using photofission fragments in studying the structure of highly neutron-rich nuclei are discussed

Evidence of interatomic Coulombic decay in ArKr after Ar 2p Auger decay

International Nuclear Information System (INIS)

Morishita, Y; Saito, N; Suzuki, I H; Fukuzawa, H; Liu, X-J; Sakai, K; Pruemper, G; Ueda, K; Iwayama, H; Nagaya, K; Yao, M; Kreidi, K; Schoeffler, M; Jahnke, T; Schoessler, S; Doerner, R; Weber, T; Harries, J; Tamenori, Y

2008-01-01

We have identified interatomic Coulombic decay (ICD) processes in the ArKr dimer following Ar 2p Auger decay, using momentum-resolved electron-ion-ion coincidence spectroscopy and simultaneously determining the kinetic energy of the ICD electron and the KER between Ar 2+ and Kr + . We find that the spin-conserved ICD processes in which Ar 2+ (3p -3 3d) 1 P and 3 P decay to Ar 2+ (3p -2 ) 1 D and 3 P, respectively, ionizing the Kr atom, are significantly stronger than the spin-flip ICD processes in which Ar 2+ (3p -3 3d) 1 P and 3 P decay to Ar 2+ (3p -2 ) 3 P and 1 D, respectively

Effect of Xe ion (167 MeV) irradiation on polycrystalline SiC implanted with Kr and Xe at room temperature

International Nuclear Information System (INIS)

Hlatshwayo, T T; Kuhudzai, R J; Njoroge, E G; Malherbe, J B; O’Connell, J H; Skuratov, V A; Msimanga, M

2015-01-01

The effect of swift heavy ion (Xe 167 MeV) irradiation on polycrystalline SiC individually implanted with 360 keV Kr and Xe ions at room temperature to fluences of 2  ×  10 16 cm −2 and 1  ×  10 16 cm −2 respectively, was investigated using transmission electron microscopy (TEM), Raman spectroscopy and Rutherford backscattering spectrometry (RBS). Implanted specimens were each irradiated with 167 MeV Xe +26 ions to a fluence of 8.3  ×  10 14 cm −2 at room temperature. It was observed that implantation of 360 keV Kr and Xe ions individually at room temperature amorphized the SiC from the surface up to a depth of 186 and 219 nm respectively. Swift heavy ion (SHI) irradiation reduced the amorphous layer by about 27 nm and 30 nm for the Kr and Xe samples respectively. Interestingly, the reduction in the amorphous layer was accompanied by the appearance of randomly oriented nanocrystals in the former amorphous layers after SHI irradiation in both samples. Previously, no similar nanocrystals were observed after SHI irradiations at electron stopping powers of 33 keV nm −1 and 20 keV nm −1 to fluences below 10 14 cm −2 . Therefore, our results suggest a fluence threshold for the formation of nanocrystals in the initial amorphous SiC after SHI irradiation. Raman results also indicated some annealing of radiation damage after swift heavy ion irradiation and the subsequent formation of small SiC crystals in the amorphous layers. No diffusion of implanted Kr and Xe was observed after swift heavy ion irradiation. (paper)

Separation of Kr-Xe system by thermal diffusion method

International Nuclear Information System (INIS)

Yoshida, Hiroshi; Numata, Kazuyoshi; Matsuda, Yuji; Ouchi, Misao; Naruse, Yuji

1979-11-01

Separation experiments of Kr-Xe system were carried out to study the possibility of adapting thermal diffusion method for concentration of krypton in a fuel reprocessing off-gas treatment process. The results are as follows. (1) A batchwise thermal diffusion column of hot tube diameter 21 mm, cold tube diameter 32 mm, effective hight 1000 mm and volume -- 500 CC is the best in separation characteristics and in ease of operation under the different conditions. (2) The overall separation factor increases with increase of the operating temperature in the column with and without reservoir. (3) The optimum operating pressure (about 400 Torr) is independent of the operating conditions such as temperature, reservoir volume and feed gas content. (4) A preliminary design of the Kr-Xe separating plant for a reprocessing plant (1500 ton-U/yr) shows the required number of columns and the total electric power. (author)

Elastic helium scattering studies of ordered overlayers of Ar, Kr, and Xe physisorbed on Ag(111)

International Nuclear Information System (INIS)

Gibson, K.D.; Cerjan, C.; Light, J.C.; Sibener, S.J.

1988-01-01

We describe experiments that measured the angle resolved intensity of He (E/sub i/ = 18 and 66 meV) elastically scattering from the surfaces of rare gas overlayers physisorbed on Ag(111). These studies were done on a layer-by-layer basis for 1, 2, 3, and ∼25 ordered overlayers of Ar, Kr, and Xe. Two types of experiments are described. The first is diffraction, where the scattered He intensity was measured as a function of the detector angle, with the incident polar and azimuthal angles held constant. In the second type of experiment, selective adsorption, we measured the specular intensity as a function of incident angle. The purpose of these experiments was to examine the He--surface potential, to assess the relative contributions that various He--rare gas pair potentials, nonadditive multibody terms, and He--substrate interactions make to the systems studied. The experiments are compared with the results of accurate close-coupling calculations, in order to quantitatively perform these assessments. The comparisons between the selective adsorption data and scattering calculations demonstrate the extreme sensitivity that such measurements have to the He--surface potential. In particular, observable changes in the calculated selective adsorption spectra appear when different He--rare gas potentials are tested, or when various nonadditive terms are included in the potential. The results suggest that further refinements in the He-heavy--rare gas pair potentials may be in order

Direct Observation of Xe and Kr Adsorption in a Xe-Selective Microporous Metal-Organic Framework

NARCIS (Netherlands)

Chen, X.; Plonka, A.M.; Banerjee, D.; Krishna, R.; Schaef, H.T.; Ghose, S.; Thallapally, P.K.; Parise, J.B.

2015-01-01

The cryogenic separation of noble gases is energy-intensive and expensive, especially when low concentrations are involved. Metal organic frameworks (MOFs) containing polarizing groups within their pore spaces are predicted to be efficient Xe/Kr solid,state adsorbents, but no experimental insights

Observation of site-specific decay processes in Ar-Kr mixed clusters following K-shell excitation of Kr

International Nuclear Information System (INIS)

Nagaya, K.; Murakami, H.; Iwayama, H.; Yao, M.

2008-01-01

Multiple ion coincidence momentum imaging measurements have been performed for an Ar-Kr mixed rare-gas cluster with an average cluster size = 100 in the 1s threshold region of Kr. The signals resulting due to the photoabsorption by Kr have been extracted on the basis of the difference in the spectra between 14.08 and 14.50 keV, i.e., on both sides of the 1s threshold for Kr. The time-of-flight spectra for the clusters reveal that multiply charged cluster ions produced as a result of inner-core excitation emit many singly charged ions such as Kr + , Ar + , ArKr + , and Ar 2 + . The abundance of daughter ions suggests the transfer of positive charges from the X-ray absorbing atom to the surrounding atoms before the Coulomb explosion is suggested from. The momentum of daughter ions is deduced from the time-of-flight and position data, and the momentum distribution shows the characteristic size dependence of the ions on the number of coincidence signals N coin , i.e., the average momentum of the Ar + ions increases with N coin , while that of the Kr + ions decreases. The N coin dependence of momentum is interpreted according to the site-dependent decay processes

CDW-EIS calculations for multiple ionization of Ne, Ar, Kr and Xe by the impact of H{sup +} and He{sup +}, including post-collisional electron emission

Energy Technology Data Exchange (ETDEWEB)

Montanari, C C; Miraglia, J E [Instituto de AstronomIa y FIsica del Espacio, casilla de correo 67, sucursal 28, C1428EGA, Buenos Aires (Argentina); Montenegro, E C, E-mail: mclaudia@iafe.uba.a [Instituto de FIsica, Universidade Federal de Rio de Janeiro, Caixa Postal 68528, Rio de Janeiro 21945-970, RJ (Brazil)

2010-08-28

We present theoretical single to quintuple ionization cross sections for Ne, Ar, Kr and Xe bombarded by H{sup +} and He{sup +}. Post-collisional contributions due to Auger-like processes are taken into account using recent photoionization data. The present continuum distorted wave-eikonal initial state (CDW-EIS) and first Born approximation results are compared with the experimental data available in the energy range of 50-10 000 keV amu{sup -1} for H{sup +} on Ne and Ar, and 50-1000 keV amu{sup -1} for the other cases. In general, the combination of the CDW-EIS with the post-collisional branching ratios describes well the multiple ionization data above 300 keV amu{sup -1}, showing a clear tendency to coalesce with the first Born approximation at high energies. The surprising result of this work is the good performance of the first Born approximation which describes rather well the experimental data of double and triple ionization, even in the intermediate energy range (50-300 keV amu{sup -1}), where direct ionization is the dominant contribution.

Measurement of the Auger decay after resonance excitation of Xe 4d and Kr 3d resonance lines

International Nuclear Information System (INIS)

Eberhardt, W.; Kalkoffen, G.; Kunz, C.

1978-03-01

The Nsub(4,5) 0sub(2,3) 0sub(2,3) Auger spectra from Xe and the Msub(4,5) Nsub(2,3) Nsub(2,3) Auger spectra from Kr are investigated for different photon energies around threshold of ionization. When exciting at the resonance line (4d 9 5s 2 5p 6 6p for Xe and 3d 9 4s 2 4p 6 5p for Kr) we observe the usual Auger multiplet structure to be shifted to higher kinetic energies. Additionally, new lines appear which can be assigned to shake-up processes int he Xe + and Kr + ions. (orig.) [de

Adsorption properties of fission gases Xe and Kr on pristine and doped graphene: A first principle DFT study

Energy Technology Data Exchange (ETDEWEB)

Vazhappilly, Tijo, E-mail: tijoj@barc.gov.in [Theoretical Chemistry Section, Chemistry Group, Bhabha Atomic Research Centre, Mumbai 400 085 (India); Ghanty, Tapan K., E-mail: tapang@barc.gov.in [Theoretical Chemistry Section, Chemistry Group, Bhabha Atomic Research Centre, Mumbai 400 085 (India); Homi Bhabha National Institute, Training School Complex, Anushakti Nagar, Mumbai 400094 (India); Jagatap, B.N. [Theoretical Chemistry Section, Chemistry Group, Bhabha Atomic Research Centre, Mumbai 400 085 (India)

2017-07-15

Graphene has excellent adsorption properties due to large surface area and has been used in applications related to gas sorption and separation. The separation of radioactive noble gases using graphene is an interesting area of research relevant to nuclear waste management. Radioactive noble gases Xe and Kr are present in the off-gas streams from nuclear fission reactors and spent nuclear fuel reprocessing plants. The entrapment of these volatile fission gases is important in the context of nuclear safety. The separation of Xe from Kr is extremely difficult, and energy intensive cryogenic distillation is generally employed. Physisorption based separation techniques using porous materials is a cost effective alternative to expensive cryogenic distillation. Thus, adsorption of noble gases on graphene is relevant for fundamental understanding of physisorption process. The properties of graphene can be tuned by doping and incorporation of defects. In this regard, we study the binding affinity of Xe and Kr in pristine and doped graphene sheets. We employ first principle calculations using density functional theory, corrected for dispersion interactions. The structural parameters obtained from the current study show excellent agreement with the available theoretical and experimental observations on similar systems. Noble gas adsorption energies on pristine graphene match very well with the available literature. Our results show that the binding energy of fission gases Xe and Kr on graphene can be considerably improved through doping the lattice with a heteroatom. - Graphical abstract: The adsorption of radioactive fission gases Xe and Kr on pristine/doped graphene is an interesting topic in the context of nuclear waste management. Previous experimental and computational studies about Xe/Kr adsorption on graphene were limited to only on pristine graphene. The doping by hetero atom changes the electronic properties of graphene and creates active sites in the lattice. Based

Independent Yields of Kr and Xe Fragments at Photofission of Odd Nuclei ^{237}Np and ^{243}Am

CERN Document Server

Gangrsky, Yu P; Myshinskii, G V; Penionzhkevich, Yu E

2004-01-01

he independent yields of fragments Kr (A=89-93) and Xe (A=135-142) at photofission of odd nuclei 237Np and 243Am are presented. The experiments were performed using the bremsstrahlung of 25 MeV electrons on the microtron of FLNR, JINR. A technique was used that included the transportation of fragments which escaped from the target with the gas flow through a capillary and the condensation of inert gases in a cryostat at the temperature of liquid nitrogen. Kr and Xe isotopes were identified by the spectra of their daughter products. The mass number distributions of the independent yields of Kr and Xe isotopes and of the complementary fragments (Y and La at the photofission of ^{237}Np and Nb and Pr at the photofission of ^{243}Am) were obtained.

Cryogenics free production of hyperpolarized 129Xe and 83Kr for biomedical MRI applications

Science.gov (United States)

Hughes-Riley, Theodore; Six, Joseph S.; Lilburn, David M. L.; Stupic, Karl F.; Dorkes, Alan C.; Shaw, Dominick E.; Pavlovskaya, Galina E.; Meersmann, Thomas

2013-12-01

As an alternative to cryogenic gas handling, hyperpolarized (hp) gas mixtures were extracted directly from the spin exchange optical pumping (SEOP) process through expansion followed by compression to ambient pressure for biomedical MRI applications. The omission of cryogenic gas separation generally requires the usage of high xenon or krypton concentrations at low SEOP gas pressures to generate hp 129Xe or hp 83Kr with sufficient MR signal intensity for imaging applications. Two different extraction schemes for the hp gasses were explored with focus on the preservation of the nuclear spin polarization. It was found that an extraction scheme based on an inflatable, pressure controlled balloon is sufficient for hp 129Xe handling, while 83Kr can efficiently be extracted through a single cycle piston pump. The extraction methods were tested for ex vivo MRI applications with excised rat lungs. Precise mixing of the hp gases with oxygen, which may be of interest for potential in vivo applications, was accomplished during the extraction process using a piston pump. The 83Kr bulk gas phase T1 relaxation in the mixtures containing more than approximately 1% O2 was found to be slower than that of 129Xe in corresponding mixtures. The experimental setup also facilitated 129Xe T1 relaxation measurements as a function of O2 concentration within excised lungs.

Cryogenics free production of hyperpolarized 129Xe and 83Kr for biomedical MRI applications☆

Science.gov (United States)

Hughes-Riley, Theodore; Six, Joseph S.; Lilburn, David M.L.; Stupic, Karl F.; Dorkes, Alan C.; Shaw, Dominick E.; Pavlovskaya, Galina E.; Meersmann, Thomas

2013-01-01

As an alternative to cryogenic gas handling, hyperpolarized (hp) gas mixtures were extracted directly from the spin exchange optical pumping (SEOP) process through expansion followed by compression to ambient pressure for biomedical MRI applications. The omission of cryogenic gas separation generally requires the usage of high xenon or krypton concentrations at low SEOP gas pressures to generate hp 129Xe or hp 83Kr with sufficient MR signal intensity for imaging applications. Two different extraction schemes for the hp gasses were explored with focus on the preservation of the nuclear spin polarization. It was found that an extraction scheme based on an inflatable, pressure controlled balloon is sufficient for hp 129Xe handling, while 83Kr can efficiently be extracted through a single cycle piston pump. The extraction methods were tested for ex vivo MRI applications with excised rat lungs. Precise mixing of the hp gases with oxygen, which may be of interest for potential in vivo applications, was accomplished during the extraction process using a piston pump. The 83Kr bulk gas phase T1 relaxation in the mixtures containing more than approximately 1% O2 was found to be slower than that of 129Xe in corresponding mixtures. The experimental setup also facilitated 129Xe T1 relaxation measurements as a function of O2 concentration within excised lungs. PMID:24135800

Measurement of Kr-85 and Xe-133 as undisturbed tracers for the representing of atmospheric transport after disposal of radioactivity from nuclear facilities; Messungen von Kr-85 und Xe-133 als ungestoerte Tracer zur Darstellung atmosphaerischer Transportvorgaenge nach Freisetzung von Radioaktivitaet aus kerntechnischen Anlagen

Energy Technology Data Exchange (ETDEWEB)

Frank, G.; Steinkopff, T. [Deutscher Wetterdienst (Germany); Salvamoser, J. [Institut fuer Angewandte Isotopen-, Gas- und Umweltuntersuchungen (IGU), Woerthsee (Germany)

2016-07-01

The Deutscher Wetterdienst (DWD, German Meteorological Service) operates since 1996 a sampling and measurement device for the radioactive rare gases Kr-85 and Xe-133 in Offenbach. These measurements are embedded in the German Measurement and Information System for Monitoring Environmental Radioactivity (Integriertes Mess- und Informationssystem zur Ueberwachung der Radioaktivitaet in der Umwelt, IMIS) [1]. In addition to these measurements the DWD is sampling rare gases in Potsdam and since 2014 in Trier in cooperation with the Bundesamt fuer Strahlenschutz (Federal Office for Radiation Protection, BfS). In the frame of the Global Atmosphere Watch (GAW)-program of the WMO the DWD operated a sampling station at the Zugspitze (Schneefernerhaus) from 1999 to 2005. This location at the Zugspitze is well suited for the observation of long distance transport of Kr-85 in the higher atmosphere. The DWD in Offenbach operates a complex analytical system for the measurement of Kr-85 and Xe-133 since 1998. This system consists of sampling with first enrichment, second enrichment, gas chromatographic separation and preparation of Krypton and Xenon and measurement of Kr-85 and Xe-133. Using the example Fukushima, it is shown, that the radioactive rare gases Kr-85 and Xe-133 are well undisturbed tracers for atmospheric transport in case of a nuclear accident or routine nuclear reprocessing plants. Measurements of Xe-133, I-131, Cs-137 and Kr-85 are correlated with source and atmospheric transport to the sampling sites at Offenbach and Potsdam.

Experimental preparation of Kr/Xe hydrate at pressures up to 160 bar

International Nuclear Information System (INIS)

Simonis, R.

1985-06-01

A compound called gas (mixture) hydrate is formed under pressurized atmosphere by reaction of krypton, xenon and a mixture of both with water. The study under review reports on preparing such hydrates experimentally under pressures up to 160 bar. The dissociation function of the hydrates is determined by low and medium-pressure experiments. Observing the formation process it was found that a hydrate layer is formed at the interface of gas and water, its separating effect almost inhibiting continuance of hydrate reactions. Strong stirring will avoid or destroy the separating layer. It is shown that at pressures above 50 bar the dissociation function psub(D) (T) gets non-linear with logarithmic pressure plotting above the absolute, reciprocal temperature. The medium-temperature experiments show that the density of the gas consisting of Xe or Kr and Xe, respectively, reaches higher values than that of the water. In this case, the system collapses and the gas is found at the bottom of the pressure flask, and the water in the top region. The gas samples taken during the mixed hydrate preparation show that Kr is accumulated in the gaseous phase, and Xe in the hydrate phase. (orig./RB) [de

I-Xe and 40Ar-39Ar analyses of silicate from the Eagle Station pallasite and the anomalous iron meteorite Enon

International Nuclear Information System (INIS)

Niemeyer, S.

1983-01-01

Silicate from two unusual iron-rich meteorites were analyzed by the I-Xe and 40 Ar- 39 Ar techniques. Enon, an anomalous iron meteorite with chondritic silicate, shows no loss of radiogenic 40 Ar at low temperature, and gives a plateau age of 4.59 +- 0.03 Ga. Although the Xe data fail to define an I-Xe correlation the inferred Pu/U ratio is more than 2 σ above the chondritic value, and the Pu abundance derived from the concentration of Pu-fission Xe is 6 times greater than the abundance inferred for CI meteorites. These findings for Enon, coupled with data for IAB iron meteorites, suggest that presence of chondritic silicate in an iron-rich meteorite is diagnostic of an old radiometric age with little subsequent thermal disturbance. The Eagle Station pallasite, the most 16 O-rich meteorite known, gives a complex 40 Ar- 39 Ar age pattern which suggests a recent severe thermal disturbance. The absence of excess 129 Xe, and the low trapped Ar and Xe contents, are consistent with this interpretation. The similarity between 40 Ar- 39 Ar data for Eagle Station and for the olivine-rich meteorite Chassigny lends credence to the previous suggestion of a connection between Chassigny and pallasites. (author)

Investigations of an excimer laser working with a four-component gaseous mixture He-Kr:Xe-HCl

Science.gov (United States)

Iwanejko, Leszek; Pokora, Ludwik J.

1991-08-01

The paper presnts working conditions of an XCI excimer laser untypical gas mixture based on KrzXe instead of pure Xe. Such a choice was influenced by the necessity of Findin9 the way to replace imported and expensive Xe by gaseous components accesible in Poland. Determining the range of changes of laser extrnal parameters which enables its proper work with the new gas mixture was the aim of same investigations results of which are presented in this paper. The laser pulse output energy and the pulse duration as a Function of supply voltage and the mixture composition are presented. The range of proper conditions for the laser working with the new mixture He-Kr:Xe--HC1 was determined. The analysis of experimental results showed that using the new mixture ensures value of energy and pulse duration comparable with the ones obtained for the mixture He-''Xe--HCl. Spectral investigations showed the lack of influence of Kr presence in the mixture on the generation spectrum of the laser. L.

I-Xe and 40Ar-39Ar dating of silicate from Weekeroo Station and Netschaevo IIE iron meteorites

International Nuclear Information System (INIS)

Niemeyer, S.

1980-01-01

Silicate inclusions from two IIE iron meteorites were dated by the I-Xe and 40 Ar- 39 Ar techniques. Weekeroo Station, a 'normal' IIE iron, shows no loss of radiogenic 40 Ar at low temperature, and the well defined 40 Ar- 39 Ar plateau yields an age of 4.54 +- 0.03 Byr. The xenon data define a good I-Xe correlation with an age of + 10.9 +- 0.5 Myr relative to Bjurbole. Despite its relatively young age, Weekeroo Station's ( 129 Xe/ 132 Xe)sub(trapped) ratio (= 0.84 +- 0.05) lies significantly below the solar value. Netschaevo silicate has a chondritic composition, unlike 'normal' IIE silicate which is more differentiated. Nevertheless Netschaevo gives a 40 Ar- 39 Ar plateau-age of only 3.79 +- 0.03 Byr, with the xenon data failing to define an I-Xe isochron. Only irons from the IAB and IIE groups contain silicate inclusions, but these two groups differ in many other respects, mostly suggesting that IAB meteorites are more primitive. The I-Xe chronology supports this suggestion inasmuch as Weekeroo Station formed well after IAB silicates. The four silicate-bearing IIE irons which have now been dated can be subdivided into distinct pairs: Weekeroo Station and Colomera formed near the beginning of the solar system, while Netschaevo and Kodaikanal both formed only 3.8 Byr ago. A review of other properties of these meteorites generally supports this subdivision. This work underscores the complexity of the history of IIE meteorites; in particular, an adequate model must account for the formation of two IIE irons at 3.8 Byr without disturbing rare gases in Weekeroo Station. All formation models are quite speculative, but the one which seems best to fit the available evidence postulates two parent bodies: the 3.8 Byr old silicate formed on one parent body, all other IIE material resided in a separate body, and subsequent collision(s) mixed the young silicate with IIE metal. (author)

On applicability of the QsUb(gg)-systematics to the description of cross sections for multinucleon transfer reactions induces by 40Ar, 86Kr, and 136Xe ions

International Nuclear Information System (INIS)

Cherepanov, E.A.; Lee Gen Soo; Mezentsev, A.N.; Volkov, V.V.

1978-01-01

Relative cross sections have been calculated for the production of gold isotopes with mass numbers of the 190-199 range in the 181 Ta+ 40 Ar, 181 Ta+ 86 Kr and 181 Ta+ 136 Xe systems at laboratory bombarding energies of 290, 550 and 840 MeV, respectively. It was assumed that gold isotopes were produced as a result of multinucleon transfers followed by neutron evaporation. The yield of primary gold isotopes was found using the Qsub(gg)-systematics, whereas the neutron evaporation process was calculated within the framework of the Jackson model. The parameters used in the calculation are the average entrance angular momentum anti l, temperature UPSILON and the nuclear parameter r 0 of exit reaction channels. For realistic values of the parameters indicated a good agreement with the experimental data obtained previously has been achieved. This provides evidence for the applicability of the Qsub(gg)-systematics to the description of multinucleon transfer reactions induced by very heavy ions

Rotational energy transfer in Na2 (A Σ) colliding with Xe, Kr, Ar, Ne, He, H2, CH4, and N2: Experiment and fitting laws

International Nuclear Information System (INIS)

Brunner, T.A.; Smith, N.; Karp, A.W.; Pritchard, D.E.

1981-01-01

Using the method of laser-induced fluorescence, we have measured level to level rate constants for rotational energy transfer (RET) in Na 2 colliding with Xe, Kr, Ar, Ne, He, H 2 , N 2 , and CH 4 . For each target gas we varied the initial rotational quantum number ji-italic over a wide range, typically 4--100, and measured approximately 60 rate constants with an average error of between 6% and 9%. The resulting base of 479 rate constants is used to test several recently proposed fitting laws. The energy corrected sudden scaling law of DePristo et al., when combined with the assumption of a power gap law for the basis rate constants k/sub l/→0, fit with only 3 parameters all of the data for a given target gas with 7%--12% average percentage deviation. Our statistical power gap law worked well and was generally the best law for those data sets with only one value of j/sub i/. The worst fits in all cases considered here were those using the exponential gap law of surprisal theory

Adsorption properties of fission gases Xe and Kr on pristine and doped graphene: A first principle DFT study

Science.gov (United States)

Vazhappilly, Tijo; Ghanty, Tapan K.; Jagatap, B. N.

2017-07-01

Graphene has excellent adsorption properties due to large surface area and has been used in applications related to gas sorption and separation. The separation of radioactive noble gases using graphene is an interesting area of research relevant to nuclear waste management. Radioactive noble gases Xe and Kr are present in the off-gas streams from nuclear fission reactors and spent nuclear fuel reprocessing plants. The entrapment of these volatile fission gases is important in the context of nuclear safety. The separation of Xe from Kr is extremely difficult, and energy intensive cryogenic distillation is generally employed. Physisorption based separation techniques using porous materials is a cost effective alternative to expensive cryogenic distillation. Thus, adsorption of noble gases on graphene is relevant for fundamental understanding of physisorption process. The properties of graphene can be tuned by doping and incorporation of defects. In this regard, we study the binding affinity of Xe and Kr in pristine and doped graphene sheets. We employ first principle calculations using density functional theory, corrected for dispersion interactions. The structural parameters obtained from the current study show excellent agreement with the available theoretical and experimental observations on similar systems. Noble gas adsorption energies on pristine graphene match very well with the available literature. Our results show that the binding energy of fission gases Xe and Kr on graphene can be considerably improved through doping the lattice with a heteroatom.

Characterization and Modeling of Materials for Kr-Xe Separations

Energy Technology Data Exchange (ETDEWEB)

Forster, Paul [Univ. of Nevada, Las Vegas, NV (United States); Naduvalath, Balakrishnan [Univ. of Nevada, Las Vegas, NV (United States); Czerwinski, Ken [Univ. of Nevada, Las Vegas, NV (United States)

2015-11-16

We sought to identify practical adsorbents for the separation of Kr from Xe through pressure swing adsorption. We spent appreciable efforts on two categories of materials: metal-organic frameworks (MOFs) and zeolites. MOFs represent a new and exciting sorbent with numerous new framework topologies and surface chemistries. Zeolites are widely used and available commercial adsorbents. We have employed a combination of gas sorption analysis to analyze gas – surface interactions, computational modelling to both aid in interpreting experimental results and to predict practical adsorbents, and in-situ crystallographic studies to confirm specific experimental results.

Characterization and Modeling of Materials for Kr-Xe Separations

International Nuclear Information System (INIS)

Forster, Paul; Naduvalath, Balakrishnan; Czerwinski, Ken

2015-01-01

We sought to identify practical adsorbents for the separation of Kr from Xe through pressure swing adsorption. We spent appreciable efforts on two categories of materials: metal-organic frameworks (MOFs) and zeolites. MOFs represent a new and exciting sorbent with numerous new framework topologies and surface chemistries. Zeolites are widely used and available commercial adsorbents. We have employed a combination of gas sorption analysis to analyze gas - surface interactions, computational modelling to both aid in interpreting experimental results and to predict practical adsorbents, and in-situ crystallographic studies to confirm specific experimental results.

Measurement of Kr-85 and Xe-133 as undisturbed tracers for the representing of atmospheric transport after disposal of radioactivity from nuclear facilities

International Nuclear Information System (INIS)

Frank, G.; Steinkopff, T.; Salvamoser, J.

2016-01-01

The Deutscher Wetterdienst (DWD, German Meteorological Service) operates since 1996 a sampling and measurement device for the radioactive rare gases Kr-85 and Xe-133 in Offenbach. These measurements are embedded in the German Measurement and Information System for Monitoring Environmental Radioactivity (Integriertes Mess- und Informationssystem zur Ueberwachung der Radioaktivitaet in der Umwelt, IMIS) [1]. In addition to these measurements the DWD is sampling rare gases in Potsdam and since 2014 in Trier in cooperation with the Bundesamt fuer Strahlenschutz (Federal Office for Radiation Protection, BfS). In the frame of the Global Atmosphere Watch (GAW)-program of the WMO the DWD operated a sampling station at the Zugspitze (Schneefernerhaus) from 1999 to 2005. This location at the Zugspitze is well suited for the observation of long distance transport of Kr-85 in the higher atmosphere. The DWD in Offenbach operates a complex analytical system for the measurement of Kr-85 and Xe-133 since 1998. This system consists of sampling with first enrichment, second enrichment, gas chromatographic separation and preparation of Krypton and Xenon and measurement of Kr-85 and Xe-133. Using the example Fukushima, it is shown, that the radioactive rare gases Kr-85 and Xe-133 are well undisturbed tracers for atmospheric transport in case of a nuclear accident or routine nuclear reprocessing plants. Measurements of Xe-133, I-131, Cs-137 and Kr-85 are correlated with source and atmospheric transport to the sampling sites at Offenbach and Potsdam.

Production of 41Ar and 79Kr gaseous radiotracers for industrial applications

International Nuclear Information System (INIS)

Yelgaonkar, V.N.; Jagadeesan, K.C.; Shivarudrappa, V.; Sharma, V.K.; Chitra, S.

2007-01-01

Radiotracers are extensively used in many industries for trouble shooting and optimization of process parameters leading to considerable savings in time and huge economic benefits. In chemical and petrochemical industries different gases and vapours flowing in the conversion reactors play a major role in the final production. Gaseous radiotracers are ideal to study hydrodynamics of gas phases in process vessels. 41 Ar and 79 Kr are the preferred gaseous radiotracers for such studies. Owing to the increase in demand from Indian industries for gas phase radiotracers, efforts have been made to produce 41 Ar and 79 Kr indigenously by irradiation of 40 Ar and enriched 78 Kr gaseous targets in research reactors. Prequalification of the containers used, safety aspects concerning accidental rupture and mandatory tests necessary for irradiation of gaseous targets in the reactors have been studied. The paper describes some of the important safety aspects involved and the results of trial irradiations on the production of 41 Ar and 79 Kr radiotracers. Standardization of suitable assay protocols for their regular production and supply for applications in industries is also described. (author)

Electron temperatures of inductively coupled Cl2-Ar plasmas

International Nuclear Information System (INIS)

Fuller, N.C.M.; Donnelly, Vincent M.; Herman, Irving P.

2002-01-01

Trace rare gases optical emission spectroscopy has been used to measure the electron temperature, T e , in a high-density inductively coupled Cl 2 -Ar plasma at 18 mTorr as function of the 13.56 MHz radio frequency power and Ar fraction. Only the Kr and Xe emission lines were used to determine T e , because of evidence of radiation trapping when the Ar emission lines were also used for larger Ar fractions. At 600 W (10.6 W cm-2), T e increases from ∼4.0±0.5 eV to ∼6.0±2.0 eV as the Ar fraction increases from 1% to 96%. In the H (inductive, bright) mode, T e , for a 'neat' chlorine plasma (including 1% of each He/Ne/Ar/Kr/Xe) increases only slightly from ∼3.8 to 4.0 eV as power increases from 450 to 750 W. This increase is much larger for larger Ar fractions, such as from ∼4.0 to 7.3 eV for 78% Ar. Most of these effects can be understood using the fundamental particle balance equation

Ar-Xe Laser: The Path to a Robust, All-Electric Shipboard Directed Energy Weapon

National Research Council Canada - National Science Library

Apruzese, J. P; Sethian, J. D; Giuliani, J. L; Wolford, M. F

2008-01-01

.... The electron beam pumped Ar-Xe laser has been investigated in an ONR-sponsored 6.1 program at NRL. The results of this program are summarized in this Memorandum Report, and indicate that the Ar-Xe laser has strong potential to meet these requirements...

Removal of I, Rn, Xe and Kr from off gas streams using PTFE membranes

Science.gov (United States)

Siemer, Darryl D.; Lewis, Leroy C.

1990-01-01

A process for removing I, R, Xe and Kr which involves the passage of the off gas stream through a tube-in-shell assembly, whereby the tubing is a PTFE membrane which permits the selective passages of the gases for removing and isolating the gases.

Formation and migration properties of the rare gases He, Ne, Ar, Ke, and Xe in nickel

International Nuclear Information System (INIS)

Melius, C.F.; Wilson, W.D.; Bisson, C.L.

1980-01-01

The energies of formation and migration of various rare gas-point defect complexes in an f.c.c. nickel lattice have been calculated for He, Ne, Ar, Kr, and Xe. Formation energies of rare gas atoms at interstitial sites are compared with those in substitutional sites. Binding energies are presented for self-interstitials and vacancies trapped to the various rare gas substitutionals. Migration energies and migration paths are also presented for various rare gas interstitials and substitutionals with and without trapped vacancies and self-interstitials. The migration energies are compared with the breakup energies for the corresponding complexes. It is found that divacancy-rare gas complexes are rather stable and will migrate at relatively low energies compared to other substitutional rare gas migration processes. (author)

Chemical activity of noble gases Kr and Xe and its impact on fission gas accumulation in the irradiated UO2 fuel

International Nuclear Information System (INIS)

Szuta, M.

2006-01-01

It is generally accepted that most of the insoluble inert gas atoms Xe and Kr produced during fissioning are retained in the fuel irradiated at a temperature lower than the threshold. Experimental data imply that we can assume that after irradiation exposure in excess of 10 18 fissions/cm 3 the single gas atom diffusion can be disregarded in description of fission gas behaviour. It is assumed that the vicinity of the fission fragment trajectory is the place of intensive irradiation induced chemical interaction of the fission gas products with UO 2 . Significant part of fission gas product is thus expected to be chemically bound in the matrix of UO 2 . Experiments with mixture of noble gases, coupled with theoretical calculations, provide strong evidence for direct bonds between Ar, Kr, or Xe atoms and the U atom of the CUO molecule. Because of its positive charge, the UO 2 2+ ion, which is isoelectronic with CUO, should form even stronger bonds with noble gas atoms, which could lead to a growing number of complexes that contain direct noble gas - to - actinide bonds. Considering the huge amount of gas immobilised in the UO 2 fuel the solution process and in consequence the re-solution process of rare gases is to be replaced by the chemical bonding process. This explains the fission gas accumulation in the irradiated UO 2 fuel. (author)

Measurements of Positronium Formation Cross Sections for Positron-Kr, Xe Scattering

Science.gov (United States)

Kauppila, W. E.; Kwan, C. K.; Li, H.; Stein, T. S.; Zhou, S.

1997-04-01

Our experimental approach(S. Zhou et al., Phys. Rev. Lett. 73, 236 (1994).) for measuring Ps formation cross sections (Q_Ps) involves passing a variable energy positron beam through a gas scattering cell and detecting the 511 keV annihilation gamma rays resulting from the decay of para-Ps and from the interaction of ortho-Ps with the walls of the scattering cell. It is found that the Q_Ps curves for both Kr and Xe rise rapidly from their formation threshold energies of 7.2 and 5.3 eV, reach maxima within about 10 eV of their thresholds and then decrease to become rather small (less than 10% of the peak heights) above 100 eV. At the maxima Q_Ps accounts for more than 50% of the total scattering cross sections. There is some evidence of possible small scale structure in the Q_Ps curves between 10 and 100 eV. The present results are consistent with the prior measurements of Diana et al.( L.M. Diana et al., in "Atomic Physics with Positrons", edited by J.W. Humberston and E.A.G. Armour (Plenum, New York and London, 1987), p. 55; and in "Positron Annihilation", edited by L. Dorikens-Vanpraet et al. (World Scientific, Singapore, 1989), p. 311.) from near threshold to 70 eV for Kr and from 15 to 100 eV for Xe.

Photoionisation study of Xe.CF{sub 4} and Kr.CF{sub 4} van-der-Waals molecules

Energy Technology Data Exchange (ETDEWEB)

Alekseev, V. A., E-mail: alekseev@va3474.spb.edu; Kevorkyants, R. [St. Petersburg State University, 7/9 Universitetskaya Nab., St. Petersburg 199034 (Russian Federation); Garcia, G. A.; Nahon, L. [Synchrotron Soleil, Orme des Merisiers, St. Aubin BP 48, 91192 Gif sur Yvette Cedex (France)

2016-05-14

We report on photoionization studies of Xe.CF{sub 4} and Kr.CF{sub 4} van-der-Waals complexes produced in a supersonic expansion and detected using synchrotron radiation and photoelectron-photoion coincidence techniques. The ionization potential of CF{sub 4} is larger than those of the Xe and Kr atoms and the ground state of the Rg.CF{sub 4}{sup +} ion correlates with Rg{sup +} ({sup 2}P{sub 3/2}) + CF{sub 4}. The onset of the Rg.CF{sub 4}{sup +} signals was found to be only ∼0.2 eV below the Rg ionization potential. In agreement with experiment, complementary ab initio calculations show that vertical transitions originating from the potential minimum of the ground state of Rg.CF{sub 4} terminate at a part of the potential energy surfaces of Rg.CF{sub 4}{sup +}, which are approximately 0.05 eV below the Rg{sup +} ({sup 2}P{sub 3/2}) + CF{sub 4} dissociation limit. In contrast to the neutral complexes, which are most stable in the face geometry, for the Rg.CF{sub 4}{sup +} ions, the calculations show that the minimum of the potential energy surface is in the vertex geometry. Experiments which have been performed only with Xe.CF{sub 4} revealed no Xe.CF{sub 4}{sup +} signal above the first ionization threshold of Xe, suggesting that the Rg.CF{sub 4}{sup +} ions are not stable above the first dissociation limit.

Inner-shell spectroscopy and exchange interaction of Rydberg electrons bound by singly and doubly charged Kr and Xe atoms in small clusters

International Nuclear Information System (INIS)

Nagasaka, Masanari; Hatsui, Takaki; Setoyama, Hiroyuki; Ruehl, Eckart; Kosugi, Nobuhiro

2011-01-01

Surface-site resolved Kr 3d 5/2 -1 5p and 3d 5/2 -1 6p and Xe 4d 5/2 -1 6p and 4d 5/2 -1 7p Rydberg excited states in small van der Waals Kr and Xe clusters with a mean size of = 15 are investigated by X-ray absorption spectroscopy. Furthermore, surface-site resolved Kr 4s -2 5p, 4s -2 6p, and 4s -1 4p -1 5p shakeup-like Rydberg states in small Kr clusters are investigated by resonant Auger electron spectroscopy. The exchange interaction of the Rydberg electron with the surrounding atoms and the induced polarization of the surrounding atoms in the singly and doubly ionized atoms are deduced from the experimental spectra to analyze different surface-site contributions in small clusters, assuming that the corner, edge, face, and bulk sites have 3, 5-6, 8, and 12 nearest neighbor atoms. These energies are almost proportional to the number of the nearest neighbor atoms. The present analysis indicates that small Kr and Xe clusters with = 15 have an average or mixture structure between the fcc-like cubic and icosahedron-like spherical structures.

(e, 2e) processes on Ne, Ar and Xe targets

Energy Technology Data Exchange (ETDEWEB)

Purohit, G; Patidar, Vinod; Sud, K K, E-mail: g_vpurohit@yahoo.co, E-mail: ghanshyam.purohit@spsu.ac.i [Department of Physics, School of Engineering, Sir Padampat Singhania University, Bhatewar, Udaipur-313 601 (India)

2010-06-01

Recently, there have been several attempts to explain the features of triple differential cross section (TDCS) for the (e, 2e) processes on inert targets Ne, Ar and Xe but there are still certain discrepancies in theoretical results and measurements, which require more theoretical efforts to understand the collision dynamics of these targets. We present in this paper the results of our modified distorted wave Born approximation (DWBA) calculation of TDCS for the ionization of Ne (2p), Ar (3p) and Xe (5p) targets. We modify the standard DWBA formalism by including the correlation-polarization potential (which is function of electron density) and compare our computed results with the available experimental and theoretical data. We observe that the polarization potential is able to improve the agreement with experimental results.

Molecular dynamic simulation of interaction of low-energy Ar and Xe ions with copper clusters at graphite surface

International Nuclear Information System (INIS)

Kornich, G.V.; Lozovskaya, L.I.; Betts, G.; Zaporozhchenko, V.I.; Faupel, F.

2005-01-01

One conducted molecular and dynamic simulation of sputtering of isolated clusters consisting of 13, 27 and 195 Cu atoms from the (0001) graphite surface by 200 eV energy Ar and Xe ions. It is shown that the factors of reflection of Ar and Xe ions from copper clusters differ from one another insignificantly, though the energy of the reflected Xe ions is essentially lower than that of Ar ions. The values of the factor of cluster sputtering by Xe ions are higher in contrast to sputtering by Ar ions. One identified two mechanisms of cluster sputtering resulting in the maximum of sputtering intensity at the polar angles near the normal one, and in periodicity of maximums within the azimuth distributions of sputtering intensity with 60 deg period [ru

Search of 2K(2ν) capture in 78 Kr and 124 Xe by means of wall-less proportional counters

International Nuclear Information System (INIS)

Volchenko, G.V.; Gavrilyuk, Yu.M.; Kuz'minov, V.V.; Osetrova, N.Ya.; Ratkevich, S.S.

1998-01-01

The technique of the experiment on the double two-neutrino K-capture search in isotopes of rare gases 78 Kr and 124 Xe is described. Multiwire wall-less proportional counters of a large volume are used in this experiment. Methods of decreasing the counter background noise in the energy range 10-100 keV are considered. These methods are based on the discrimination of events on the coordinate along the anode filament and the pulse rise time. The sensitivity of the experimental installation is estimated according to the half-life 78 Kr (1.2 x 10 21 years) and 124 Xe (2.6 x 10 20 years) with respect to the 2K(2ν) capture (68% certain level)

Dosimetry of the radioactive noble gases

International Nuclear Information System (INIS)

Soldat, J.K.; Bramson, P.E.; Parker, H.M.

1973-01-01

Methods are described that were used for estimations of the radiation dose rate to various human tissues from the radioactive gases of Ar, Kr, and Xe following inhalation or immersion in a semi-infinite cloud. Dose rates to the whole-body, lungs, adipose tissues, and testes were calculated following inhalation; and dose rates to the skin, whole-body, lungs, and testes from a semi-infinite cloud were calculated for 39 Ar, 41 Ar, 83 Kr, 85 Kr, 87 Kr, 88 Kr, 131 Xe, 133 Xe, 135 Xe, 137 Xe, 138 Xe, and also 88 Rb found in equilibrium with its parent 88 Kr and 138 Cs found in equilibrium with its parent 138 Xe. (U.S.)

LASER RADIATION CHARACTERISTICS (BRIEF COMMUNICATIONS): Conversion of KrCl and XeCl laser radiation to the visible spectral range by stimulated Raman scattering in lead vapor

Science.gov (United States)

Evtushenko, Gennadii S.; Mel'chenko, S. V.; Panchenko, Aleksei N.; Tarasenko, Viktor F.

1990-04-01

Conversion of KrCl and XeCl laser radiation by stimulated Raman scattering was achieved in lead vapor. The KrCl laser radiation was converted into three lines in the visible region at λ = 406, 590, and 723 nm by transitions from both the ground and first excited levels of the lead atom. The conversion efficiency of XeCl laser radiation of low spatial coherence was found to be limited by the activation of a competing nonlinear process.

Double beta decay searches of 134Xe, 126Xe and 124Xe with large scale Xe detectors

International Nuclear Information System (INIS)

Barros, N; Thurn, J; Zuber, K

2014-01-01

The sensitivity for double beta decay studies of 134 Xe and 124 Xe is investigated assuming a potential large scale Xe experiment developed for dark matter searches depleted in 136 Xe. The opportunity for an observation of the 2νββ - decay of 134 Xe is explored for various scenarios. A positive observation should be possible for all calculated nuclear matrix elements. The detection of 2ν ECEC of 124 Xe can be probed in all scenarios covering the theoretical predicted half-life uncertainties and a potential search for 126 Xe is discussed. The sensitivity to β + EC decay of 124 Xe is discussed and a positive observation might be possible, while β + β + decay still remains unobservable. The performed studies take into account solar pp–neutrino interactions, 85 Kr beta decay and remaining 136 Xe double beta decay as background components in the depleted detector. (paper)

Kinetic analysis of rare gas metastable production and optically pumped Xe lasers

Science.gov (United States)

Demyanov, A. V.; Kochetov, I. V.; Mikheyev, P. A.; Azyazov, V. N.; Heaven, M. C.

2018-01-01

Optically pumped all-rare-gas lasers use metastable rare gas atoms as the lasing species in mixtures with He or Ar buffer gas. The metastables are generated in a glow discharge, and we report model calculations for the optimal production of Ne*, Ar*, Kr* and Xe*. Discharge efficiency was estimated by solving the Boltzmann equation. Laser efficiency, gain and output power of the CW optically pumped Xe laser were assessed as functions of heavier rare gas content, pressure, optical pump intensity and the optical path length. It was found that, for efficient operation the heavier rare gas content has to be of the order of one percent or less, and the total pressure—in the range 0.3-1.5 atm. Output power and specific discharge power increase approximately linearly with pump intensity over the output range from 300-500 W cm-2. Ternary mixtures Xe:Ar:He were found to be the most promising. Total laser efficiency was found to be nearly the same for pumping the 2p8 or 2p9 state, reaching 61%-70% for a pump intensity of ~720 W cm-2 when the Xe fraction was in the range 0.001 ÷ 0.01 and Ar fraction—0.1 ÷ 0.5. However, when the 2p8 state was pumped, the maximum total efficiency occurred at larger pressures than for pumping of the 2p9 state. The discharge power density required to sustain a sufficient Xe* number density was in the range of tens of watts per cubic centimeter for 50% Ar in the mixture.

Xe isotopic abundances in enstatite meteorites and relations to other planetary reservoirs

International Nuclear Information System (INIS)

Lee, Jee-Yon; Marti, Kurt; Wacker, John F.

2009-01-01

This paper describes the interpretation of xenon that was measured in the Abee meteorite. Reported Xe isotopic abundances in enstatite chondrites (EC's) show some variability, and this makes comparisons to other solar system reservoirs rather difficult. In contrast, we find uniform Xe isotopic abundances in the EC chondrite Abee for a variety of clasts, except for 128 Xe and 129 Xe, the isotopes affected by neutron capture in I and by extinct 129 I. We report averages for the studied clasts which are consistent within error limits with OC-Xe and with the Q-Xe signature. On the other hand, the elemental abundance ratios Ar/Xe are variable between clasts. A strongly reducing environment which is indicated for enstatite meteorites was generally assumed to be consistent with conditions existing in the early inner solar system. Xe isotopic abundances in SNC meteorites from Mars and also those in some terrestrial wells show that distinct isotopic reservoirs coexisted on the same planets. In particular, the Xe isotopic signatures in terrestrial well gases show the presence of a minor distinct component in two of the reported four well gases. These authors suggested that the extra component represents solar Xe, but we show that also a meteoritic xenon reservoir of the Abee-Xe structure is an option. The reported Xe data in Ar-rich (subsolar) EC's show isotopic abundances slightly lighter than those in Abee-Xe, but the relative abundances of Ar, Kr, and Xe indicate only a minor component of elementally unfractionated solar Xe. The elemental ratios suggest rather a different origin for these gases: the loading of solar particles into grain surfaces during exposure at elevated temperatures during accretion of matter in the inner solar system. A model of this type was suggested for the accretion of gases now observed in the atmosphere on Venus. We note that disks of crystalline silicates (including enstatite and olivine) have been observed in T Tauri stars during their early

Mass spectrometrical study of rare gas compositions and neutron capture effects in Yamato-74191 (L 3) Chondrite

International Nuclear Information System (INIS)

Takaoka, N.; Nagao, K.

1980-01-01

The unequilibrated hypersthene chondrite Yamato-74191 was studied mass spectrometrically for rare gases released at various temperatures. Cosmogenic gases dominate in He and Ne. The meteorite contains large amounts of trapped Ar, Kr and Xe, and radiogenic 40 Ar and 129 Xe. Cosmic-ray irradiation and K-Ar ages were determined. In addition to spallogenic components of Kr and Xe, isotopic excesses of 8 sup(O)Kr, 82 Kr, 128 Xe and 126 Xe relative to AVCC-Kr and -Xe were found. The ratio of 80 Kr-excess to 82 Kr-excess is 2.66 after correction for spallogenic Kr. A correlation between 128 Xe/ 132 Xe and 129 Xe/ 132 Xe was found. The 129 Xe/ 132 Xe ratio for trapped Xe in Yamato-74191 was determined as 1.12 +- 0.29 with the correlation plot. The excesses found in Yamato-74191 are best explained by epithermal neutron capture on Br and I, and by the 127 I(n,2nβ) 126 Xe reaction. Using neutron-produced 80 Kr, the neutron slowing-down density was estimated to be 0.14 +- 0.03 cm -3 sec -1 . A minimum mass and a preatmospheric radius was estimated to be 470 kg and 32 cm, respectively. (orig.)

Comparison of KrF and ArF excimer laser treatment of biopolymer surface

Energy Technology Data Exchange (ETDEWEB)

Michaljaničová, I. [Department of Solid State Engineering, University of Chemistry and Technology, 166 28 Prague (Czech Republic); Slepička, P., E-mail: petr.slepicka@vscht.cz [Department of Solid State Engineering, University of Chemistry and Technology, 166 28 Prague (Czech Republic); Heitz, J.; Barb, R.A. [Institute of Applied Physics, Johannes Kepler University Linz, A-4040 Linz (Austria); Sajdl, P. [Department of Power Engineering, University of Chemistry and Technology, 166 28 Prague (Czech Republic); Švorčík, V. [Department of Solid State Engineering, University of Chemistry and Technology, 166 28 Prague (Czech Republic)

2015-06-01

Highlights: • The influence of ArF and KrF laser on biopolymer surface was determined. • ArF laser acts predominantly on biopolymer surface. • PHB roughness is increased similarly for both applied wavelengths. • Roughness of nanostructures can be precisely controlled. • ArF laser introduces nitrogen on PHB surface. - Abstract: The goal of this work was the investigation of the impact of two different excimer lasers on two biocompatible and biodegradable polymers (poly-L-lactide and poly hydroxybutyrate). Both polymers find usage in medical and pharmaceutical fields. The polymers were modified by KrF and ArF excimer lasers. Subsequently the impact on surface morphology, surface chemistry changes, and thermal properties was studied by means of confocal and AFM microscopy, FTIR and XPS spectroscopy and DSC calorimetry. Under the same conditions of laser treatment it was observed that ArF laser causes more significant changes on surface chemistry, surface morphology and pattern formation on the polymers under investigation. The data obtained in this work can be used for a wide range of possible applications, in tissue engineering or in combination with metallization in electronics, e.g. for biosensors.

Superficial Velocity Effects on HZ-PAN and AgZ-PAN for Kr/Xe Capture

Energy Technology Data Exchange (ETDEWEB)

Welty, Amy Keil [Idaho National Lab. (INL), Idaho Falls, ID (United States); Garn, Troy Gerry [Idaho National Lab. (INL), Idaho Falls, ID (United States); Greenhalgh, Mitchell Randy [Idaho National Lab. (INL), Idaho Falls, ID (United States)

2016-04-01

Nearly all previous testing of HZ-PAN and AgZ-PAN was conducted at the same flow rate in order to maintain consistency among tests. This testing was sufficient for sorbent capacity determinations, but did not ensure that sorbents were capable of functioning under a range of flow regimes. Tests were conducted on both HZ-PAN and AgZ-PAN at superficial velocities between 20 and 700 cm/min. For HZ-PAN, Kr capacity increased from 60 mmol/kg to 110 mmol/kg as superficial velocity increased from 21 to 679 cm/min. Results for AgZ-PAN were similar, with capacity ranging from 72 to 124 mmol/kg over the same range of superficial. These results are promising for scaling up to process flows, demonstrating flexibility to operate in a broad range of superficial velocities while maintaining sorbent capacity. While preparing for superficial velocity testing it was also discovered that AgZ-PAN Xe capacity, previously observed to diminish over time, could be recovered with increased desorption temperature. Further, a substantial Xe capacity increase was observed. Previous room temperature capacities in the range of 22-25 mmol Xe/kg AgZ-PAN were increased to over 60 mmol Xe/kg AgZ-PAN. While this finding has not yet been fully explored to optimize activation and desorption temperatures, it is encouraging.

XeCl Excimer Laser with Three- and Four-Component Mixture of Active Gases

International Nuclear Information System (INIS)

Iwanejko, L.; Pokora, L.

1998-01-01

Selected results of investigations of a XeCl excimer laser employing a new type (four-component)of mixture of gases, He-Kr:Xe-HCl, are presented. The mixture includes, instead of Xe, a mixture of not-separated Kr and Xe gases, much less expensive than pure xenon. A comparison of durations and energies of pulses generated in the XeCl excimer laser using three- or four-component gaseous active medium (He-Xe-HCl or He-Kr:Xe-HCl) is made. The investigations have been carried out with the use of a laser system with UV preionization and self sustained pumping discharge. (author)

Fano factors of rare gases and their mixtures

International Nuclear Information System (INIS)

Lima, E.P. de; Salete, M.; Leite, S.C.P.; Alves, M.A.F.; Policarpo, A.J.P.

1982-01-01

Measurements of FW (Fano factor x mean energy to make an ion-pair) for several non metastable Penning gas mixtures were made using the proportional scintillation process. Taking for W the values that correspond to 5.3 MeV alpha particles, upper limits of F were determined. The following results were obtained: 100% Xe, FW = 3.247, F <= 0.15 +- 0.03; 100% Ar, FW = 10.536, F <= 0.40 +- 0.03; Ar + 80% Xe, FW = 4.635, F <= 0.21 +- 0.03; Ar + 5% Kr, FW = 9.397, F <= 0.37 +- 0.06; Ar + 24% Xe, FW = 5.093, F <= 0.23 +- 0.02; Ar + 20% Kr, FW = 3.038, F <= 0.12 +- 0.03; Ar + 20% Xe, FW = 3.582, F <= 0.16 +- 0.02; Ar + 79% Kr, FW = 3.113, F <= 0.13 +- 0.02; Ar + 5% Xe, FW = 3.204, F <= 0.14 +- 0.03; 100% Kr, FW = 4.584, F <= 0.19 +- 0.02. (orig.)

Etching microscopic defects in polycarbonate due to high dose ArF or KrF laser exposure

Energy Technology Data Exchange (ETDEWEB)

Jaleh, B. [Physics Department, Bu- Alisina University, Hamadan (Iran, Islamic Republic of); Parvin, P. [Physics Department, Amirkabir University, P.O. Box 15875-4413, Hafez Ave, Tehran (Iran, Islamic Republic of) and Laser Research Center, Atomic Energy Organization of Iran, AEOI, Tehran (Iran, Islamic Republic of) ]. E-mail: parvin@aut.ac.ir; Katoozi, M. [National Radiation Protection Department, AEOI, Tehran (Iran, Islamic Republic of); Zamani, Z. [Laser Research Center, Atomic Energy Organization of Iran, AEOI, Tehran (Iran, Islamic Republic of); Zare, A. [Laser Research Center, Atomic Energy Organization of Iran, AEOI, Tehran (Iran, Islamic Republic of)

2005-11-15

The ArF or KrF excimer laser exposure on the polycarbonate (PC) with corresponding doses higher than {phi}{sub th}5.2J/cm{sup 2}, at 32mJ/cm{sup 2} fluence per pulse and 5Hz pulse repetition rate (PRR), induces regular defects leading to self assembled defect structure following electrochemical etching (ECE). We have observed the conical-like structure for {phi}>{phi}{sub th}, whereas the polymer experiences hardening effect due to crosslinking when {phi}<{phi}{sub th}. Subsequently, conical-like, structure turns into track-like pits developing under ECE multiple treeing. Self assembled defect structure may be seen by naked eye as white spots, despite SEM illustrates a type of periodic pit formation-morphology. The exact explanation of the effect is not well understood yet. It looks like alpha tracks in the polymer surface, however the PC pieces were simply treated by excimer lasers at high doses, and they have not been exposed to the nuclear particles afterwards. We could not observe those effects at 308nm (XeCl laser) or longer wavelengths at 351nm (XeF laser) where UV photoablation does not occur. It indicates that UV ablation establishes surface degradation at shorter wavelengths, leading to laser micro etching. The mean track (defect) density is about one order of magnitude greater than the normal alpha tracks. Increasing UV doses, polymer undergoes a plateau, corresponding to etched defect saturation on PC.

Etching microscopic defects in polycarbonate due to high dose ArF or KrF laser exposure

International Nuclear Information System (INIS)

Jaleh, B.; Parvin, P.; Katoozi, M.; Zamani, Z.; Zare, A.

2005-01-01

The ArF or KrF excimer laser exposure on the polycarbonate (PC) with corresponding doses higher than φ th 5.2J/cm 2 , at 32mJ/cm 2 fluence per pulse and 5Hz pulse repetition rate (PRR), induces regular defects leading to self assembled defect structure following electrochemical etching (ECE). We have observed the conical-like structure for φ>φ th , whereas the polymer experiences hardening effect due to crosslinking when φ th . Subsequently, conical-like, structure turns into track-like pits developing under ECE multiple treeing. Self assembled defect structure may be seen by naked eye as white spots, despite SEM illustrates a type of periodic pit formation-morphology. The exact explanation of the effect is not well understood yet. It looks like alpha tracks in the polymer surface, however the PC pieces were simply treated by excimer lasers at high doses, and they have not been exposed to the nuclear particles afterwards. We could not observe those effects at 308nm (XeCl laser) or longer wavelengths at 351nm (XeF laser) where UV photoablation does not occur. It indicates that UV ablation establishes surface degradation at shorter wavelengths, leading to laser micro etching. The mean track (defect) density is about one order of magnitude greater than the normal alpha tracks. Increasing UV doses, polymer undergoes a plateau, corresponding to etched defect saturation on PC

85Kr and 39Ar background in GENIUS

International Nuclear Information System (INIS)

Klapdor Kleingrothaus, H.V.; Tomei, C.

2003-01-01

GENIUS is a proposal for a large-scale detector of rare events like double beta decay, cold dark matter and low-energy solar neutrinos in real time. The idea of GENIUS is to operate a large amount of 'naked' Ge detectors in liquid nitrogen, with the aim of reducing the background down to a level of 10 -3 counts/kg keV yr. In this work, we investigate the contribution to the background of GENIUS coming from argon ( 39 Ar) and krypton ( 85 Kr) contamination in the liquid nitrogen

Successive composition of two laser channels upon excitation of He-Ar-Xe (2.03 μm) and Ar-Xe (1.73 μm) mixtures by uranium fission fragments

International Nuclear Information System (INIS)

Pikulev, A A; Tsvetkov, V M; Sosnin, P V; Sinyanskii, A A

2009-01-01

The operation efficiency of the scheme with successive composition of two laser channels upon excitation of the active medium by uranium-235 fission fragments is studied experimentally and numerically. For the He:Ar:Xe = 380:380:1 mixture (at a pressure of 1 atm and the lasing wavelength λ = 2.03 μm) the maximum lasing power of a double channel (1 kW) is almost twice that of a single channel (540 W). Calculations show that in the case of ideal composition (without losses on mirrors) the lasing power of the double channel can be increased to 1.2 kW. For the Ar:Xe = 380:1 mixture (the pressure is 0.5 atm, λ = 1.73 μm) the maximum lasing power of the double channel (620 W) is slightly above that of the single channel (520 W), which is caused by the losses on aluminum mirrors employed for channel doubling and by a negative effect of optical inhomogeneities. In the case of ideal composition, the lasing power can be increased to 830 W. (lasers)

Quasimolecular emission near the Xe(5p 56s 1,3 P 1 - 5p 6 1 S 0) and Kr (4p 55s 1,3 P 1 - 4p 6 1 S 0) resonance lines induced by collisions with He atoms

Science.gov (United States)

Alekseeva, O. S.; Devdariani, A. Z.; Grigorian, G. M.; Lednev, M. G.; Zagrebin, A. L.

2017-02-01

This study is devoted to the theoretical investigation of the quasimolecular emission of Xe*-He and Kr*-He collision pairs near the Xe (5p 56s 1,3 P 1 - 5p 6 1 S 0) and Kr (4p 55s 1,3 P 1 - 4p 6 1 S 0) resonance atomic lines. The potential curves of the quasimolecules Xe(5p 56s) + He and Kr(4p 55s) + He have been obtained with the use of the effective Hamiltonian and pseudopotential methods. Based on these potential curves the processes of quasimolecular emission of Xe*+He and Kr*+He mixtures have been considered and the spectral distributions I(ħΔω) of photons emitted have been obtained in the framework of quasistatic approximation.

Total and elastic electron scattering cross sections from Xe at intermediate and high energies

International Nuclear Information System (INIS)

Garcia, G; Pablos, J L de; Blanco, F; Williart, A

2002-01-01

Experimental total electron scattering cross sections from Xe in the energy range 300-5000 eV have been obtained with experimental errors of about 3%. The method was based on the measurement of the attenuation of a linear electron beam through a Xe gas cell in combination with an electron spectroscopy technique to analyse the energy of the transmitted electrons. Differential and integral elastic cross sections have been calculated using a scattering potential method which includes relativistic effects. The consistency of our theoretical and experimental results is also discussed in the paper. Finally, analytical formulae depending on two parameters, namely the number of target electrons and the atomic polarizability, are given to reproduce the experimental data for Ne, Ar, Kr and Xe in the energy range 500-10 000 eV

Experimental study of relative level populations in beam-foil excited Ar+7 and Kr+7

International Nuclear Information System (INIS)

Bashkin, S.; Oona, H.; Veje, E.

1981-01-01

The relative level populations in beam-foil excited sodium-like argon (Ar VIII) and copper-like krypton (Kr VIII) have been studied at 2 MeV projectile energy. In Ar VIII, the 3p and the 3d terms are strongly excited. The level population decreases rapidly with increasing value of the principal quantum number n, reaches a minimum for levels with n = 5 or 6, but increases then and reaches a strong maximum for levels with n approximately 11. Also the Kr VIII data show a population maximum for levels with n = 11. The strong 3p and 3d level excitations in Ar VIII are explained as selective inner-shell processes which can be understood in the molecular-orbital electron-promotion picture. The preferential population of high-flying Rydberg states is explained as resulting from a near-resonance electron transfer from the valence band of the carbon foil to the projectile. This process takes place when the projectile leaves the back of the foil. (Auth.)

The total cross section as a function of energy for elastic scattering of noble gas atoms

International Nuclear Information System (INIS)

Linse, C.A.

1978-01-01

Precise relative measurements of the total cross-sections as a function of velocity is presented for the systems Ar-Ar, Ar-Kr, Kr-Ar, Ar-Xe, Ne-Ar, Ne-Kr, and Ne-Xe, the primary beam particle being mentioned first. A discription of the apparatus is given. Then the method for extracting total cross-sections from the measured beam attenuation is analyzed. A comparison is made with total cross-sections calculated from various potentials that have been proposed in the literature

Differential cross sections for inelastic scattering of electrons on Kr and Xe atoms at intermediate energies

International Nuclear Information System (INIS)

Filipovic, D.M.

1989-01-01

Electron-impact excitation of the larger- number noble-gas atoms is a way of understanding excitation mechanisms in atomic collisional processes. Krypton and xenon have the largest atomic number of all the stable noble gases. Therefore, effects dependent on the size of a target atom, such as alignment and orientation of the atomic outer shell charge cloud after collisional excitation, are best observed by studying these atoms. Normalized, absolute differential cross sections (DCS's) for the lowest electronic states of Kr and Xe atoms, at intermediate energies, are the subject of this report

The far from equilibrium structure of argon clusters doped with krypton or xenon.

Science.gov (United States)

Lindblad, A; Bergersen, H; Rander, T; Lundwall, M; Ohrwall, G; Tchaplyguine, M; Svensson, S; Björneholm, O

2006-04-28

Heterogeneous clusters created by doping Ar host clusters with Kr or Xe are shown to have radically different structures from the mixed clusters of the same type created by co-expansion of Ar-Kr or Ar-Xe gas mixtures. In contrast to the co-expansion case, the doped mixed clusters can be produced with Kr or Xe on the surface and Ar in the bulk. With the doping technique it is thus possible to control the surface composition of a specific cluster. A study of the cluster properties as a function of the doping pressure is also reported for the case of Ar clusters doped with Xe. The clusters have been studied by means of synchrotron radiation based X-ray photoelectron spectroscopy.

Average energy expended per ion pair, exciton enhanced ionization (Jesse effect), electron drift velocity, average electron energy and scintillation in rare gas liquids

International Nuclear Information System (INIS)

Doke, T.; Hitachi, A.; Hoshi, Y.; Masuda, K.; Hamada, T.

1977-01-01

Precise measurements of W-values, the average energy expended per electron-hole pair in liquid Ar and Xe, were made by the electron-pulse method, and that in liquid Kr by the steady conduction current method. The results showed that the W-values were clearly smaller than those in gaseous Ar, Xe and Kr as predicted by Doke. The results can be explained by the conduction bands which exist in these rare gas liquids as well as in the solid state. The enhanced ionization yield was observed for Xe-doped liquid Ar, and it was attributed to the ionizing excitation transfer process from Ar excitons to doped Xe. This is very similar to the Jesse effect in the gas phase. The saturated value of the enhanced ionization was in good agreement with the theoretical value, and it provides strong evidence for the existence of the exciton states in liquid Ar. Fano factors in liquid Ar, Kr, Xe and Xe-doped liquid Ar have been estimated from the Fano Formula, and they were smaller than those in the gas phase. The drift velocity of electrons in liquid Ar, liquid Ar-gas mixtures and liquid Xe have been measured with gridded ionization chambers. The average electron energy in liquid Ar has been measured. The electron-induced scintillations of liquid Xe and Ar have been studied. (Kato, T.)

TARGET EXCITATION IN BARE ION XE/AR COLLISIONS STUDIED BY ELECTRON TARGET ION COINCIDENCES

NARCIS (Netherlands)

DENIJS, G; HOEKSTRA, R; MORGENSTERN, R

We present electron spectra resulting from collisions of bare ions N-15(7+) and C-13(6+) on Ar and the charge state distribution of target ions resulting from C-13(6+)-Xe collisions. From both type of experiments we find evidence that electron capture accompanied by target excitation is an important

The present status of rare gas release control

International Nuclear Information System (INIS)

Yamamoto, Hiroshi

1974-01-01

Of the rare gases Ar, Kr and Xe released from nuclear facilities, the problem of release control can be confined to 41 Ar, 85 Kr and 133 Xe. The cases of the latter two are described, as 41 Ar is not much significant. 133 Xe, having relatively short half-life, can be dealt sufficiently by holding-up in case of light water reactors. 85 Kr of long half-life must be removed : the methods are low temperature adsorption, liquefaction distillation, absorption and diaphragm method. As for future problem, there is disposal of concentrated rare gas. (Mori, K.)

The use of Kr-81m in ventilation imaging

International Nuclear Information System (INIS)

Pommet, R.; Therain, F.

1982-01-01

Radioactive gases are very useful in the study of pulmonary disorders because they allow an assessment of regional lung function. The most widely used radioactive gases are Xe-133 and, more recently, Kr-81m. This paper is a review of the physical characteristics of Kr-81m, its production from the parent Rb-81, the different methods to produce Rb-81, the different types of generators which can be used in hospitals, and the clinical applications of pulmonary ventilation imaging. The paper suggests that Kr-81m offers several advantages over previous methods that used Xe-133 due to its improved spatial resolution, its capacity to provide superimposable ventilation and perfusion images in multiple projections, and its total lung dose which is ten times lower than that of Xe-133

Principle tests of reactor pumped laser of 3He-Ar-Xe system

International Nuclear Information System (INIS)

Chen Hande; Jin Xingxing; Yang Chengde

1994-01-01

A nuclear reactor-pumped laser was demonstrated firstly by using the 3 He(P,n) 3 H reaction to excite a 3 He-Ar-Xe laser. Lasing was observed on the 1.73 μm (5d (3/2) 1 -6p(5/2) 1 transition) in Xe I. The CAEP Pulsed Reactor (CFBR-II) was used as a source of fast neutrons moderated by a 50 mm thick polyethylene sleeve around the laser cell. A laser cell was constructed from K 9 glass tubing 600 mm long and Φ34 mm with each end cut at Brewster's angle (quartz). The laser cell was baked out to 10 -3 Pa prior to filling with research-grade mixture ( 3 He/Ar/Xe = 34.7: 34.7: 0.267 kPa). A dielectric-coated 2 m radius-curvature back mirror (99.7% reflectivity at 1.73 μm) and a flat output coupler (Φ30 mm) were used to form the optical cavity. The cavity optics were placed outside the cell as shown in Fig.3. A schematic of the experimental configuration is shown. Typical laser signals obtained with the Ge detector (-80 degree C) are also shown. Laser output lags the fast neutron pulse by the neutron thermalization time (∼278 μs). The observed light output was shown to be caused by stimulated emission, because the signal disappeared when the reflecting (flat) mirror was covered. This precludes the possibility that the phenomenon was the result of γ-radiation interaction with the detector or the air in the light path. The measured laser energy was 80 times the maximum possible fluorescence energy. The observed wavelength was measured to be 1.73 μm by using glass filters. Laser output duration was approximately 735 μs

Low energy electron attachment to SF6 in N2, Ar, and Xe buffer gases

International Nuclear Information System (INIS)

Hunter, S.R.; Carter, J.G.; Christophorou, L.G.

1989-01-01

The electron attachment rate constants k/sub a/ for SF 6 have been measured in dilute mixtures of SF 6 in high pressure (>1 atm) N 2 , Ar, and Xe buffer gases at room temperature (T≅300 K) over a wide E/N range (electric field strength to gas number density ratio), corresponding to mean electron energies from near thermal electron energies (≅0.04 eV) to ≅4.3 eV. Particular attention has been paid to the effects of space charge distortion, molecular impurities, and changes in the electron energy distribution function on the measured electron attachment rate constant values at the lower E/N values in these mixtures. The present measured thermal electron attachment rate constants in SF 6 /N 2 and SF 6 /Xe gas mixtures are in excellent agreement with recent accurate measurements of these parameters in several SF 6 /buffer gas mixtures. At higher values, the present SF 6 /N 2 measurements are in fair agreement with previous measurements, while no previous measurements using Ar and Xe buffer gases have been published. These measurements have been used in numerical two term, spherical harmonic Boltzmann equation analyses of the electron motion in these gas mixtures to obtain the low energy ( 6 . The present derived electron attachment cross sections are compared with recently measured and derived nondissociative and dissociative electron attachment cross sections for SF 6

Variable surface composition and radial interface formation in self-assembled free, mixed Ar/Xe clusters

International Nuclear Information System (INIS)

Tchaplyguine, M.; Maartensson, N.; Lundwall, M.; Oehrwall, G.; Feifel, R.; Svensson, S.; Bjoerneholm, O.; Gisselbrecht, M.; Sorensen, S.

2004-01-01

Using photoelectron spectroscopy, we demonstrate how the self-assembling process of cluster formation in an adiabatic expansion leads to radial segregation and layering as well as to variable surface composition for binary Ar/Xe clusters. The radial structuring can be qualitatively understood from the different interatomic bonding strengths of the two components

Production of highly charged ion beams Kr32+, Xe44+, Au54+ with Electron String Ion Source (ESIS) Krion-2 and corresponding basic and applied studies

Science.gov (United States)

Donets, D. E.; Donets, E. D.; Donets, E. E.; Salnikov, V. V.; Shutov, V. B.

2010-09-01

Electron String Ion Source (ESIS) Krion-2 (JINR, Dubna) was used for basic and applied research in various aspects of multiply charged heavy ions production. Energy recuperation mode in ESIS has been proofed first and used for production of highly charged ions 84Kr28+÷84Kr32+, 124Xe40÷124Xe44 and Au51+÷ Au54+. Krion-2 ESIS was mounted on high voltage (HV) platform of LU-20 Linac and used as an injector of highly charged ions during Nuclotron run N° 41. Krion-2 ESIS has produced 3.0.107 124Xe42+ ions per pulse of 7 μs duration. This ion beam was injected into LU-20 and Nuclotron, accelerated up to energy of 186 GeV and the extracted Xe beam was used for physics experiments. Electron String Ion Source Krion-2 demonstrated the high reliability and stability running during 30 days on HV platform. We believe that it is due to an extremely low electron beam power, provided by using the electron string mode of operation: 50 W pulse power and about 10 W average power. Other possible application of ESIS could be its use in injection complexes of synchrotrons and cyclotrons for cancer therapy. Slow and fast extraction of C4+ and C6+ beams from Krion-2 ESIS were preliminary studied towards ESIS optimization for medical accelerators requirements.

Multi-kiloampere, electron-beam generation using metal photo-cathodes driven by ArF and KrF lasers

Energy Technology Data Exchange (ETDEWEB)

Carlson, R L; Moya, S S; Ridlon, R N; Seitz, G J; Shurter, R P [Los Alamos Natl. Lab., Los Alamos, NM (United States)

1997-12-31

An electron-beam-pumped laser operating at ArF (193 nm) or KrF (248 nm) producing 35 MW (3.5 J in 100 ns) has been used to illuminate a micro-machined aluminum cathode. The cathode was pulsed to 2.75 MV at fields of 185 kV/cm (15-cm AK gap) using REX (a 4-MV, 5-kA, 85-ns) pulsed-diode machine. The extracted current versus incident laser power (the quantum efficiency) was measured for KrF at 5x10{sup -5} and for ArF which was significantly higher at 1x10{sup -3}. Current densities of 100 A/cm{sup 2} and total currents of 2 kA have been achieved, the latter by increasing the cathode area in proportion to the laser power. (author). 8 figs., 14 refs.

A study of capillary discharge lamps in Ar-Hg and Xe-Hg mixtures

International Nuclear Information System (INIS)

Denisova, N; Gavare, Z; Revalde, G; Skudra, Ja; Veilande, R

2011-01-01

Low-pressure capillary discharge lamps in Ar-Hg and Xe-Hg mixtures are studied. The discharge size is 0.5 mm (500 μm) in radius. According to the literature, such types of plasma sources are classified as microplasmas. The studies include spectrally resolved optical measurements, tomographic reconstructions and numerical simulations using the collisional-radiative model for an Ar-Hg plasma. We discuss the problems of theoretical modelling and experimental diagnostics of microplasma sources. It is shown that the conventional collisional-radiative model, based on the assumption that transportation of atoms in the highly excited states can be neglected, has limitations in modelling a capillary discharge in an Ar-Hg mixture. It is found that diffusion of highly excited mercury atoms to the wall influences the emission properties of the capillary discharge. We have concluded that applications of the emission tomography method to microplasmas require a special analysis in each particular case.

Theoretical Investigation of the Bistability Effect in Non-Self-Sustained Discharges in Kr and Ar

International Nuclear Information System (INIS)

Dyatko, N.A.; Napartovich, A.P.

2004-01-01

The electron energy distribution function and the related plasma parameters in non-self-sustained discharges in Kr and Ar are studied theoretically. The investigations are carried out by numerically solving the corresponding Boltzmann equation for the electron energy distribution function with allowance for electron-electron collisions. The electron energy distribution and electron density are calculated self-consistently as functions of the intensity q of the source of secondary electrons and the magnitude of the reduced electric field E/N. The main goal of the investigations was to determine the conditions under which the plasma exhibits bistable parameters. Calculations show that, for discharges in Kr, there is a certain range of q and E/N values in which the Boltzmann equation has two different stable solutions. For an Ar plasma, such a bistability effect was not found: over the parameter range under consideration, the Boltzmann equation has a unique solution. Various plasma parameters (such as the effective electron temperature, electron drift velocity, and electron current density) are calculated for different discharge conditions, including those corresponding to the bistability effect

Rotational excitation of linear triatomic molecules: Ar, Kr + N2O, CO2

International Nuclear Information System (INIS)

Farrar, J.M.; Parson, J.M.; Lee, Y.T.

1974-01-01

Rotational excitation of N 2 O and CO 2 in collisions with Ar and Kr has been studied by crossing two supersonic molecular beams and detecting scattered products with a mass spectrometer. Measurement of the time of flight spectrum of the products as a function of laboratory scattering angle theta indicates that the inelasticity is concentrated in the forward direction in the center of mass system. Difference between CO 2 and N 2 O are discussed briefly

The electron-impact ionization of Ar and Kr revisited: A critical analysis of double-to-single ionization cross section ratio measurements using the fast-atom-beam technique

International Nuclear Information System (INIS)

Tarnovsky, V.; Becker, K.

1992-01-01

We report new measurements of the absolute electron-impact double ionization cross sections for Ar and Kr and of the ratios of double-to-single ionization for impact energies from threshold to 200 eV using the crossed electron-beam - fast-atom-beam technique. The work was motivated by the recently highlighted spread of about 30% in the Ar 2+ /Ar + ionization cross section ratios obtained by several groups using different experimental techniques. Such a spread is inconsistent with statistical uncertainties of typically 3% or less that were quoted for the various reported ratios. A similar situation exists for Kr where the spread among the recently published Kr 2+ /Kr + ionization cross section ratios is about 15%. We made an attempt to identify all potential systematic errors inherent to the fast-beam technique that could affect the measurement of cross section ratios with special emphasis on those systematic errors that could influence the detection of singly and doubly charged product ions differently. We found Ar 2+ /Ar + and Kr 2+ /Kr + cross section ratios of, respectively 0.066±0.007 and 0.087±0.008 at 100 eV which confirm earlier measurements using the same experimental technique. The error limits on cross sections ratios of multiple-to-single ionization for the same target atom and at least ±10% for ratios of single ionization cross sections for different target species. Our error limits are dominated by systematic uncertainties of the apparatus which do not cancel when cross section ratios are measured, since the ratios are obtained under similar, but not identical experimental conditions. (orig.)

Long-term storage of 85Kr in amorphous zeolite 5A

International Nuclear Information System (INIS)

Penzhorn, R.D.; Noppel, H.E.; Dorea, A.; Guenther, K.; Leitzig, H.; Schuster, P.

1984-01-01

Ar, Kr and Xe can be immobilized in type A zeolites as well as in mordenite and chabazite, when the original crystal structure is hydrothermally vitrified in the presence of the densified gas. Zeolites containing a high percentage of earth alcali metals yield encapsulates that are thermally very stable. Gas fixation conditions are essentially independent of the form of aggregation of the matrix. Noble gas encapsulates were characterized by their specific surface area as well as by microprobe analysis, X-ray analysis and electron diffraction. The results indicate that Kr is immobilized in units smaller than the size of a zeolite crystal. The thermal conductivity of zeolites was determined experimentally in various fluid media. With the data obtained the heat transport through a final storage vessel cooled by natural air convection was calculated. The estimated temperature profiles correlate well with those obtained in experiments simulating a storage containment. To verify the process, active samples having specific activities up to 30 mCi/g have been prepared. Leaching results demonstrate the chemical stability of the Kr/5A encapsulates. A semi-pilot facility based on the one-way autoclave concept has been constructed and demonstrated in operation

Competition between electronic energy transfer and relaxation in Xe doped Ar and Ne matrices studied by photoelectron spectroscopy

International Nuclear Information System (INIS)

Schwentner, N.; Koch, E.E.

1976-01-01

Thin films of solid Ar and Ne doped with 1% Xe were excited with photons in the energy range from 10 eV to 20 eV in order to measure the energy distribution of the emitted electrons. Binding energies of th host and guest levels are deduced. When host excitons are excited, strong emission of electrons is observed indicating an efficient transfer of the host exciton energy to the Xe guest atoms. The energy of the free excitons is transferred, as can be deduced from the kinetic energy of the photoemitted electrons, rather than the energy of the bound (self-trapped) excitons which are observed in luminescence experiments. Furthermore, there is a striking difference between the Ar and the Ne matrix: In the Ne matrix a fast relaxation from the n = 2 to the n = 1 state was observed and only the energy of the n = 1 exciton is transferred even when higher excitons are excited, in contrast to Ar, where the transferred energy is higher for excitation of the n = 2 excitons than for n = 1. From these observations, time hierarchies for the competition between electronic energy transfer and relaxation are deduced. (orig.) [de

A first-principles study of He, Xe, Kr and O incorporation in thorium carbide

Energy Technology Data Exchange (ETDEWEB)

Pérez Daroca, D., E-mail: pdaroca@tandar.cnea.gov.ar [Gerencia de Investigación y Aplicaciones, Comisión Nacional de Energía Atómica, Av. General Paz 1499, 1650 San Martín, Buenos Aires (Argentina); Consejo Nacional de Investigaciones Científicas y Técnicas, 1033 Buenos Aires (Argentina); Llois, A.M. [Gerencia de Investigación y Aplicaciones, Comisión Nacional de Energía Atómica, Av. General Paz 1499, 1650 San Martín, Buenos Aires (Argentina); Consejo Nacional de Investigaciones Científicas y Técnicas, 1033 Buenos Aires (Argentina); Mosca, H.O. [Gerencia de Investigación y Aplicaciones, Comisión Nacional de Energía Atómica, Av. General Paz 1499, 1650 San Martín, Buenos Aires (Argentina); Instituto de Tecnología Jorge A. Sabato, UNSAM-CNEA, Av. General Paz 1499, 1650 San Martín, Buenos Aires (Argentina)

2015-05-15

Thorium-based materials are currently being investigated in relation with their potential utilization in Generation-IV reactors as nuclear fuels. Understanding the incorporation of fission products and oxygen is very important to predict the behavior of nuclear fuels. A first approach to this goal is the study of the incorporation energies and stability of these elements in the material. By means of first-principles calculations within the framework of density functional theory, we calculate the incorporation energies of He, Xe, Kr and O atoms in Th and C vacancy sites, in tetrahedral interstitials and in Schottky defects along the 〈1 1 1〉 and 〈1 0 0〉 directions. We also analyze atomic displacements, volume modifications and Bader charges. This kind of results for ThC, to the best authors’ knowledge, have not been obtained previously, neither experimentally, nor theoretically. This should deal as a starting point towards the study of the complex behavior of fission products in irradiated ThC.

Development of 85Kr separation from the off-gas of the large reprocessing plant: Findings of the prototype test plants ADAMO and KRETA

International Nuclear Information System (INIS)

Ammon, R. von; Bumiller, W.; Hutter, E.; Neffe, G.

1977-01-01

Operation of the KRETA and ADAMO test plants so far has shown that rectification of the ternary system N 2 -Kr-Xe is possible if certain limiting concentrations of Kr and Xe in the feedwater are kept. At Xe concentrations [de

Wavelengths and energy levels of Xe V and Xe VI obtained by collision-based spectroscopy

International Nuclear Information System (INIS)

Larsson, M.O.; Gonzalez, A.M.; Hallin, R.; Heijkenskjoeld, F.; Nystroem, B.; O'Sullivan, G.; Weber, C.; Waennstroem, A.

1996-01-01

We have utilized collision-based spectroscopy to investigate the spectra of Xe V and Xe VI. The radiation emitted following electron capture by 50 keV Xe 5+ and 60 keV Xe 6+ ions impinging on a He (Ar) gas target has been recorded in the 350-6000 (1200-2500) A wavelength region. A number of new energy levels of Xe V and Xe VI have been established from lines identified by us. In particular, we have observed and identified transitions from the 5s 2 5p4f (5s 2 4f) configuration of Xe V (Xe VI). The analysis was supported by Hartree-Fock calculations. (orig.)

Gain limits of a Thick GEM in high-purity Ne, Ar and Xe

CERN Document Server

Miyamoto, J; Peskov, V

2010-01-01

The dependence of the avalanche charge gain in Thick Gas Electron Multipliers (THGEM) on the purity of Ne, Ar and Xe filling gases was investigated. The gain, measured with alpha-particles in standard conditions (atmospheric pressure, room temperature), was found to considerably drop in gases purified by non-evaporable getters. On the other hand, small N2 admixtures to noble gases resulted in high reachable gains. The results are of general relevance in the operation of gas-avalanche detectors in noble gases, particularly that of two-phase cryogenic detectors for rare events.

Process for recovering xenon from radioactive gaseous wastes

International Nuclear Information System (INIS)

Kishimoto, Tsuneo.

1980-01-01

Purpose: To recover pure xenon economically and efficiently by amply removing radioactive krypton mixed in xenon without changing the rectifying capacity of an xenon rectifying system itself. Method: Xe containing radioactive Kr(Kr-85) is rectified to reduce the concentration of radioactive Kr. Thereafter, non-radioactive Kr or Ar is added to Xe and further the rectification is carried out. The raw material Xe from the Xe adsorption system of, for example, a radioactive gaseous waste disposal system is cooled to about 100 0 C by a heat-exchanger and thereafter supplied to a rectifying tower to carry out normal rectification of Xe thereby to reduce the concentration of Kr contained in Xe at the tower bottom to the rectification limit concentration. Then, non-radioactive Kr is supplied via a precooler to the tower bottom to continue the rectification, thus the Xe fractions at the tower bottom, in which the concentration of radioactive Kr is reduced, being compressed and recovered. (Kamimura, M.)

Photoionization pathways and thresholds in generation of Lyman-α radiation by resonant four-wave mixing in Kr-Ar mixture

OpenAIRE

Oleg A. Louchev; Norihito Saito; Yu Oishi; Koji Miyazaki; Kotaro Okamura; Jumpei Nakamura; Masahiko Iwasaki; Satoshi Wada

2016-01-01

We develop a set of analytical approximations for the estimation of the combined effect of various photoionization processes involved in the resonant four-wave mixing generation of ns pulsed Lyman-α (L-α) radiation by using 212.556 nm and 820-845 nm laser radiation pulses in Kr-Ar mixture: (i) multi-photon ionization, (ii) step-wise (2+1)-photon ionization via the resonant 2-photon excitation of Kr followed by 1-photon ionization and (iii) laser-induced avalanche ionization produced by genera...

The influence of ion implantation on the surface properties of metals and alloys

International Nuclear Information System (INIS)

Grant, W.A.; Carter, G.

1975-10-01

The report falls into three sections: (1) annealing behaviour of high dose rare gas (Ne, Ar, Kr, Xe) implantations into silicon; (2) measurement of projected and lateral range parameters for low energy heavy ions (Ar, Cu, Kr, Cd, Xe, Cs, Dy, W, Au, Pb, Bi) in silicon by Rutherford backscattering; (3) surface chemistry of ion implanted solids (e.g. corrosion, catalysis, oxidation, synthesis of compounds in ion implanted layers). (U.K.)

VUV spectroscopy of rare gas van der Waals dimers

International Nuclear Information System (INIS)

Dehmer, P.M.; Pratt, S.T.

1982-01-01

We have undertaken a systematic study of the photoionization spectra of the homonuclear and heteronuclear rare gas dimers in order to better understand the nature of the bonding in the Rydberg states adnd ions of these molecules. We have obtained results for Ar 2 , Kr 2 , Xe 2 , NeAr, NeKr, NeXe, ArKr, ArXe, and KrXe. Of the remaining dimer species (Ne 2 and the Herare gas dimers), only Ne 2 has been studied using photoionization mass spectrometry. The results of the present series of experiments provide information both on the excited states of the neutral dimers and on the ground and excited states of the dimer ions. Using the data obtained in these measurements, we are able to compile for the first time a nearly complete list of ground state dissociation energies for the homonuclear and heteronuclear rare gas dimer ions. Somewhat less complete results are obtained for the excited states of these species. The observed trends in binding energy provide an excellent example of the systematic changes that occur as a result of changes in atomic orbital energies, polarizability, and internuclear distance, and these trends can be explained qualitatively in terms of simple molecular orbital theory

Methane activation using Kr and Xe in a dielectric barrier discharge reactor

International Nuclear Information System (INIS)

Jo, Sungkwon; Lee, Dae Hoon; Kim, Kwan-Tae; Kang, Woo Seok; Song, Young-Hoon

2014-01-01

Methane has interested many researchers as a possible new energy source, but the high stability of methane causes a bottleneck in methane activation, limiting its practical utilization. To determine how to effectively activate methane using non-thermal plasma, the conversion of methane is measured in a planar-type dielectric barrier discharge reactor using three different noble gases—Ar, Kr, and Xe—as additives. In addition to the methane conversion results at various applied voltages, the discharge characteristics such as electron temperature and electron density were calculated through zero-dimensional calculations. Moreover, the threshold energies of excitation and ionization were used to distinguish the dominant particle for activating methane between electrons, excited atoms, and ionized atoms. From the experiments and calculations, the selection of the additive noble gas is found to affect not only the conversion of methane but also the selectivity of product gases even under similar electron temperature and electron density conditions

Mound Laboratory activities for the Division of Physical Research: July--December 1975

International Nuclear Information System (INIS)

1976-01-01

Research and development are reported in the following areas: isotope separation and production for Ar, C, He, Kr, Ne, O, S, and Xe; testing of cubic B crystals for superconductivity; metal hydride research on band theory and electronic structure and spin-lattice relaxation times for VH/sub x/; separation chemistry of Pu, 231 Pa, 230 Th, 229 Th, and 234 U; adsorption of U and Pu by bone char; separation research for Ca and S isotopes; molecular beam scattering for Ar--Kr; and transport properties for the systems Ne--Ar, Ne--Kr, and Ar--Kr

Lattice distortion in hcp rare gas solids

Science.gov (United States)

Grechnev, A.; Tretyak, S. M.; Freiman, Yu. A.

2010-04-01

The lattice distortion parameter δ ≡c/a-√8/3 has been calculated as a function of molar volume for the hcp phases of He, Ar, Kr, and Xe. Results from both semi-empirical potentials and density functional theory are presented. Our study shows that δ is negative for helium in the entire pressure range. For Ar, Kr, and Xe δ changes sign from negative to positive as the pressure increases, growing rapidly in magnitude at higher pressures.

80 A/cm2 electron beams from metal targets irradiated by KrCl and XeCl excimer lasers

Science.gov (United States)

Beloglazov, A.; Martino, M.; Nassisi, V.

1996-05-01

Due to the growing demand for high-current and long-duration electron-beam devices, laser electron sources were investigated in our laboratory. Experiments on electron-beam generation and propagation from aluminium and copper targets illuminated by XeCl (308 nm) and KrCl (222 nm) excimer lasers, were carried out under plasma ignition due to laser irradiation. This plasma supplied a spontaneous accelerating electric field of about 370 kV/m without an external accelerating voltage. By applying the modified one-dimensional Poisson equation, we computed the expected current and we also estimated the plasma concentration during the accelerating process. At 40 kV of accelerating voltage, an output current pulse of about 80 A/cm2 was detected from an Al target irradiated by the shorter wavelength laser.

Demonstration of a CW diode-pumped Ar metastable laser operating at 4  W.

Science.gov (United States)

Han, J; Heaven, M C; Moran, P J; Pitz, G A; Guild, E M; Sanderson, C R; Hokr, B

2017-11-15

Optically pumped rare gas lasers are being investigated as potential high-energy, high beam quality systems. The lasing medium consists of rare gas atoms (Rg=Ne, Ar, Kr, or Xe) that have been electric discharge excited to the metastable np 5 (n+1)s P3 2 state. Following optical excitation, helium (He) at pressures of 200-1000 Torr is used as the energy transfer agent to create a population inversion. The primary technical difficulty for this scheme is the discharge production of sufficient Rg* metastables in the presence of >200  Torr of He. In this Letter, we describe a pulsed discharge that yields >10 13   cm -3 Ar* in the presence of He at total pressures up to 750 Torr. Using this discharge, a diode-pumped Ar* laser providing 4.1 W has been demonstrated.

Prospect of drug distribution to hepatic cancer in intra-arterial infusion chemotherapy. Examination by infusion of sup(81m)Kr and /sup 133/Xe via catheter into hepatic artery

Energy Technology Data Exchange (ETDEWEB)

Sasaki, Y; Imaoka, S; Matsui, Y; Ishikawa, O; Taniguchi, K [Osaka Prefectural Center for Adult Diseases (Japan)

1982-04-01

Cannulation into the hepatic artery under laparotomy was performed to nine patients of non-resectable hepatic cancer (eight of hepatocellular carcinoma, and one of cholangiocellular carcinoma), and injected sup(81m)Kr (Tsub(1/2) = 13 sec.) continuously via catheter into hepatic artery as the model of continuous intra-arterial infusion chemotherapy, and /sup 133/Xe (Tsub(1/2) = 5.3 days) by bolus injection as the model of one-shot ones. During and immediately after injection, sequential scintigrams were carried out and simultaneously images were acquired on a medical computer. Higher radioactivities of both sup(81m)Kr and /sup 133/Xe were observed in tumor than non-tumor region in seven of eight patients of hepatocellular carcinoma. The radioactive ratio of tumor to non-tumor (T/C ratio) was over 1.0 in these cases. This result indicated that there was more arterial blood flow in tumor than non-tumor region, and it could be expected to obtain higher distribution of drugs in tumor on both continuous and one-shot infusion chemotherapy. The pattern of distribution of sup(81m)Kr changed according to positions of patients, and in some cases T/C ratio was higher in other positions than supine position. The most effective position of the intra-arterial infusion chemotherapy could be selected by this method. This technique seems to make it possible to prospect the arrival of drugs to the tumor and presume the effectiveness of intra-arterial infusion chemotherapy.

Multi-Column Experimental Test Bed Using CaSDB MOF for Xe/Kr Separation

Energy Technology Data Exchange (ETDEWEB)

Welty, Amy Keil [Idaho National Lab. (INL), Idaho Falls, ID (United States); Greenhalgh, Mitchell Randy [Idaho National Lab. (INL), Idaho Falls, ID (United States); Garn, Troy Gerry [Idaho National Lab. (INL), Idaho Falls, ID (United States)

2016-03-01

Processing of spent nuclear fuel produces off-gas from which several volatile radioactive components must be separated for further treatment or storage. As part of the Off-gas Sigma Team, parallel research at INL and PNNL has produced several promising sorbents for the selective capture of xenon and krypton from these off-gas streams. In order to design full-scale treatment systems, sorbents that are promising on a laboratory scale must be proven under process conditions to be considered for pilot and then full-scale use. To that end, a bench-scale multi-column system with capability to test multiple sorbents was designed and constructed at INL. This report details bench-scale testing of CaSDB MOF, produced at PNNL, and compares the results to those reported last year using INL engineered sorbents. Two multi-column tests were performed with the CaSDB MOF installed in the first column, followed with HZ-PAN installed in the second column. The CaSDB MOF column was placed in a Stirling cryocooler while the cryostat was employed for the HZ-PAN column. Test temperatures of 253 K and 191 K were selected for the first column while the second column was held at 191 K for both tests. Calibrated volume sample bombs were utilized for gas stream analyses. At the conclusion of each test, samples were collected from each column and analyzed for gas composition. While CaSDB MOF does appear to have good capacity for Xe, the short time to initial breakthrough would make design of a continuous adsorption/desorption cycle difficult, requiring either very large columns or a large number of smaller columns. Because of the tenacity with which Xe and Kr adhere to the material once adsorbed, this CaSDB MOF may be more suitable for use as a long-term storage solution. Further testing is recommended to determine if CaSDB MOF is suitable for this purpose.

Analysis of XeC1 Emission in a Hollow Cathode Discharge.

Science.gov (United States)

1981-06-01

excited homopolar molecule, e.g., Xe2 , Hg2 The term exciplex refers to an electronically excited heteropolar complex, e.g., KrF , XeOH , XeCl , which...frequently overlooked and both homopolar and heteropolar systems are commonly referred to as excimers, Excimers are formed by the interaction between two...mode and a non-scanning mode. Scanning is performed using a 1 rpm motor and produces plots of in- tensity versus wavelength. The non-scanning mode is

Experimental investigation of the chemistry of excited states of rare gases. Annual technical progress report, October 15, 1976--October 14, 1977

International Nuclear Information System (INIS)

Setser, D.W.

1978-01-01

Tunable dye laser fluorescence has been combined with the flowing afterglow technique as a method for studying reactive intermediates present in the flowing afterglow. The radiative lifetimes and two-body quenching rate constants (with Ar carrier gas) for the Ar*(3p 5 ,4p) and Ar*(3p 5 ,5p) excited states were reported in the preceding year. During this year, we have measured the Ar* product states from the two-body quenching. More than 50% of the quenching leads directly to intermultiplet transfer to Ar(4s) states, rather than to intramultiplet cascade down the Ar(4p) manifold. Using this technique we also have studied the Xe(5p 5 ,6p') and Xe(5p 5 ,7p) excited states and radiative lifetimes, two-body quenching and the product states from quenching have been ascertained. These data should be of value for modeling energy flow pathways of rare gases excited by high energy electrons. A method has been developed for studying the quenching of the XeF(B) and KrF(B) by a variety of reagent molecules. A preliminary account of this work was published (number 5 in the publication list). Much additional experimental work has been done and a definitive study of the electronic quenching of XeF(B) and KrF(B) is in progress. Efforts to interpret (and publish) our comprehensive studies of the reactive quenching of the Kr( 3 P 2 ) and Xe( 3 P 2 ) by fluorine and chlorine-containing molecules has continued (see numbers 4, 6 and 8 in the publication listing). Two more manuscripts are in final stages of preparation. Of particular importance has been the development of methods for simulating and interpreting the bound-free emission spectra from the very high vibrational levels of the xenon and krypton fluorides and chlorides. Experiments have been done to measure the branching ratios for (i) ArF* formation from reactive quenching of Ar( 3 P 2 ) with fluorine-containing reagents and (ii) KrBr* and Br* formation for Kr( 3 P 2 ) reacting with some bromine-containing molecules

Low energy collision experiments using the beam guide technique. Charge transfer cross sections of Ar/sup 3+/ and Kr/sup 3+/ in their own gases

Energy Technology Data Exchange (ETDEWEB)

Okuno, Kazuhiko; Kaneko, Yozaburo

1986-12-01

The trajectories of charged particles moving in an octopole ion beam guide (OPIG) are computer-simulated for various initial conditions of motion. Boundary conditions between the stable and unstable regions of beam trajectory in OPIG are obtained. These calculated results are very useful for operation of OPIG under the best condition. In low energy collision experiments using the beam guide technique, cross sections of one-, two- and three-electron capture processes in collision systems of Ar/sup 3+/-Ar and Kr/sup 3+/-Kr are measured in energy region from 0.375 to 768 eV in center-of-mass system. In both collision systems, one-electron capture reaction is predominant in higher energy side, however, the dominant reaction changes from one-electron capture reaction to the symmetric resonant three-electron capture reaction in the low energy region below about 10 eV. As was predicted, it was first confirmed that each cross section obtained for symmetric resonant triple-charge-transfer reaction of Ar/sup 3+/ and Kr/sup 3+/ at the low energy end of Ecm = 0.375 eV is larger than both cross sections of symmetric resonant double-charge-transfer for the doubly charged ion and symmetric resonant single-charge-transfer for the singly charged ion.

Noble gases in Mars atmosphere: new precise analysis with Paloma

Science.gov (United States)

Sarda, Ph.; Paloma Team

2003-04-01

The Viking mission embarked a mass spectrometer designed by Alfred O. Nier that yielded the first determination of the elemental and isotopic composition of noble gases in Mars atmosphere. For example, the 40Ar/36Ar ratio in martian air is roughly 10 fold that in terrestrial air. This extraordinary accomplishment, however, has furnished only partial results with large analytical uncertainties. For example, we do not know the isotopic composition of helium, and only very poorly that of Ne, Kr and Xe. In planetary science, it is fundamental to have a good knowledge of the atmosphere because this serves as a reference for all further studies of volatiles. In addition, part of our present knowledge of Mars atmosphere is based on the SNC meteorites, and again points to important differences between the atmospheres of Earth and Mars. For example the 129Xe/132Xe ratio of martian atmosphere would be twice that of terrestrial air and the 36Ar/38Ar ratio strongly different from the terrestrial or solar value. There is a need for confirming that the atmospheric components found in SNC meteorites actually represents the atmosphere of Mars, or to determine how different they are. Paloma is an instrument designed to generate elemental and isotopic data for He, Ne, Ar, Kr and Xe (and other gases) using a mass spectrometer with a purification and separation line. Gas purification and separation did not exist on the Vicking instrument. Because Paloma includes purification and separation, we expect strong improvement in precision. Ne, Ar and Xe isotope ratios should be obtained with an accuracy of better than 1%. Determination of the presently unknown ^3He/^4He ratio is also awaited from this experiment. Knowledge of noble gas isotopes in Mars atmosphere will allow some insight into major planetary processes such as degassing (^3He/^4He, 40Ar/36Ar, 129Xe/130Xe, 136Xe/130Xe), gravitational escape to space (^3He/^4He, 20Ne/22Ne), hydrodynamic escape and/or impact erosion of the

Application of Kr-81m gas for chronic obstructive pulmonary disease. A comparison of various inhalation techniques

Energy Technology Data Exchange (ETDEWEB)

Kawakami, K; Katsuyama, N i; Anno, I i; Harada, J; Kuroda, T [Jikei Univ., Tokyo (Japan). School of Medicine

1978-11-01

The Kr-81m ventilation study was performed by the following four inhalation techniques. 1) Spontaneous respiration with Kr-81m in air (Sp). 2) Serial inhalation of Kr-81m from residual volume to total lung capacity (VC). 3) Bolus inhalation of 50 ml of Kr-81m from the level of functional residual capacity (FRC), and 4) residual volume (RV), followed by air, to total lung capacity. Scintiphotos were taken during 10 sec of breathholding for VC, FRC, RV inhalation techniques and during tidal breathing for Sp technique, in a sitting position, by a scinticamera (Pho/Gamma HP). Twenty-three of the 28 subjects showed uneven distribution of the washout time in the Xe-133 study, 5 cases have a normal Xe-133 study. In severe obstructive changes with marked delay of the Xe-133 washout time, inhalation defects of Kr-81m were imaged in all techniques. In minor degrees of obstruction associated with slight delay of the washout, FRC and RV techniques detected abnormalities, whilst images by Sp and VC techniques showed homogeneous distribution of Kr-81m. This is due to rebreathing effect on Sp and to opening of partial airway obstruction in a high lung volume on VC technique. RV technique had a disadvantage for imaging of abnormalities in the lower lung fields, because Kr-81m concentration is low in the lower lung fields, due to physiological closure of the small airway. In 3 of 5 cases of asymptomatic asthma with a normal Xe-133 study, uneven distribution in RV technique was the only abnormality detected. FRC technique was most sensitive for slight obstructive changes in the upper lung fields as well as in the lower. For the ventilation study using Kr-81m, a combined test of Sp, VC, RV and FRC inhalation techniques is useful for early detection of the small airway disease and evaluation of the degree of abnormalities.

Shock disturbance of the I-Xe system

International Nuclear Information System (INIS)

Caffee, M.W.; Hohenberg, C.M.; Podosek, F.A.; Swindle, T.D.

1982-01-01

Three separate samples of the meteorite Bjurbole were artificially shocked at pressures of 70 kb, 200 kb, and 400 kb. Analysis of xenon released in stepwise heating shows that the I-Xe system of the 400 kb sample is substantially altered by the shock loading, and it is no longer possible to infer an age or trapped xenon composition for that sample. The 200-kb and 70-kb samples display isotopic structures progressively less altered demonstrating the gradations in shock disturbance likely to be found in natural systems. Interpretations of the I-Xe and Ar-40-Ar-39 systems for several naturally shocked meteorites are also presented. New data for Arapahoe do not confirm the previously reported age and trapped xenon composition, demonstrating instead that its I-Xe structure has been strongly disturbed by shock

Interatomic decay of inner-valence ionized states in ArXe clusters: Relativistic approach

International Nuclear Information System (INIS)

Fasshauer, Elke; Pernpointner, Markus; Gokhberg, Kirill

2013-01-01

In this work we investigate interatomic electronic decay processes taking place in mixed argon-xenon clusters upon the inner-valence ionization of an argon center. We demonstrate that both interatomic Coulombic decay and electron-transfer mediated decay (ETMD) are important in larger rare gas clusters as opposed to dimers. Calculated secondary electron spectra are shown to depend strongly on the spin-orbit coupling in the final states of the decay as well as the presence of polarizable environment. It follows from our calculations that ETMD is a pure interface process taking place between the argon-xenon layers. The interplay of all these effects is investigated in order to arrive at a suitable physical model for the decay of inner-valence vacancies taking place in mixed ArXe clusters.

Dry aerosol of monodisperse millimicrospheres for ventilation imaging: Production, delivery system, and clinical results in comparison with /sup 81m/Kr and /sup 127/Xe

Energy Technology Data Exchange (ETDEWEB)

Koehn, H; Mostbeck, A; Klech, H; Kummer, F; Angelberger, P; Strigl, A; Zolle, I

1985-05-01

The production of monodisperse human albumin millimicrospheres (diameter 1 ..mu..m) and labeling with /sup 99m/Tc is described. A system constructed to nebulize and deliver a dry aerosol yielded a lung delivery efficiency of approximately 25%. In 48 patients without and with varying degrees of chronic obstructive lung disease, quantitative comparison with /sup 81m/Kr (penetration index, regional distribution of activity in the lungs) demonstrated similar penetration of the particles to the lung periphery (r = 0.89 and r = 0.94, respectively). Qualitative comparison with /sup 81m/Kr or /sup 127/Xe showed complete or a high degree of diagnostic agreement in all but one patient. Semiquantitative scoring of hot spots as a substrate of local turbulent airflow showed a close inverse correlation (r = -0.82) with the forced expiratory volume in 1 s (FEV 1.0%), thus providing additional information about the severity of the airway obstruction. In 24 patients with suspected pulmonary embolism, complete agreement between aerosol and /sup 81m/Kr images was found in all patients studied. For same-day ventilation/perfusion studies, labeling of the millimicrospheres with /sup 111/In yielded images of comparable quality to those obtained with the /sup 99m/Tc-labeled aerosol.

Mound Facility activities in chemical and physical research: July--December 1977

International Nuclear Information System (INIS)

1978-01-01

Isotope separation of Ar, C, 3 He, Kr, Ne, O, and Xe isotopes is reported. TiFeH/sub x/, TiCoH/sub x/, TiCuH/sub x/, and VH/sub x/ were studied using NMR (proton relaxation times). VD/sub x/ and VT/sub x/ were synthesized. The problem of calculating the valence state of Pu is discussed. A series solution to the plutonium (N,H) characteristic equation is suggested. Shipments of 231 Pa, 230 Th, and 229 Th are reported. Separation and processing of 234 U are also reported. Theoretical methods were developed to calculate temperature distributions as functions of water flow rate in liquid thermal diffusion columns. Diffusion coefficients were measured from 300 to 1200 0 K for Kr-Xe and Kr-Ar. New thermal diffusion factors are submitted for Ne-Ar

Surface effect of KrF laser exposure on ECE of alpha particle tracks in polycarbonate polymer

Energy Technology Data Exchange (ETDEWEB)

Parvin, P. [Physics Department, Amirkabir University, P.O. Box 15875-4413, Hafez Ave, Tehran (Iran, Islamic Republic of) and Laser Research Center, Atomic Energy Organization of Iran, AEOI, Tehran (Iran, Islamic Republic of)]. E-mail: parvin@aut.ac.ir; Jaleh, B. [Physics Department, Bu Ali Sina University, Hamadan (Iran, Islamic Republic of); Sheikh, N. [Gamma Irradiation Center, AEOI, Tehran (Iran, Islamic Republic of); Amiri, N. [Physics Department, Emam Hossien University, Tehran (Iran, Islamic Republic of)

2005-11-15

The optical penetration depth for polycarbonate (PC) at 308nm due to XeCl laser is about 450{mu}m while those of KrF (248nm) and ArF (193nm) lasers become noticeably shorter to 1{mu}m and 20nm, respectively, to show the strong superficial absorption at shorter UV wavelengths. On the other hand, KrF laser exposure on polycarbonate, at doses above 6J/cm{sup 2}, creates the surface crosslinking. In spite of several reliable methods available, such as 'hot set' and 'gel content', to determine the bulk crosslinking, there are a few consistent techniques to evaluate the surface crosslinking effect quantitatively. It includes hardening measurements using nanoindenter or AFM (atomic force microscopy). In this work, we present a technique for the measurement of superficial crosslinking, based on electrochemical etching of alpha irradiated polycarbonate accordingly. The mean diameter of the developed tracks nonlinearly decreases for KrF laser treatment at higher doses. The relative shrinkage of track diameters due to UV exposure before alpha irradiation, comparing to those without UV pre-radiation, indicates that UV laser makes the polymer surface hardened. The variation of mean track diameters can be strongly used to quantify the surface crosslinking.

Surface effect of KrF laser exposure on ECE of alpha particle tracks in polycarbonate polymer

International Nuclear Information System (INIS)

Parvin, P.; Jaleh, B.; Sheikh, N.; Amiri, N.

2005-01-01

The optical penetration depth for polycarbonate (PC) at 308nm due to XeCl laser is about 450μm while those of KrF (248nm) and ArF (193nm) lasers become noticeably shorter to 1μm and 20nm, respectively, to show the strong superficial absorption at shorter UV wavelengths. On the other hand, KrF laser exposure on polycarbonate, at doses above 6J/cm 2 , creates the surface crosslinking. In spite of several reliable methods available, such as 'hot set' and 'gel content', to determine the bulk crosslinking, there are a few consistent techniques to evaluate the surface crosslinking effect quantitatively. It includes hardening measurements using nanoindenter or AFM (atomic force microscopy). In this work, we present a technique for the measurement of superficial crosslinking, based on electrochemical etching of alpha irradiated polycarbonate accordingly. The mean diameter of the developed tracks nonlinearly decreases for KrF laser treatment at higher doses. The relative shrinkage of track diameters due to UV exposure before alpha irradiation, comparing to those without UV pre-radiation, indicates that UV laser makes the polymer surface hardened. The variation of mean track diameters can be strongly used to quantify the surface crosslinking

Threshold collision-induced dissociation of diatomic molecules: a case study of the energetics and dynamics of O2- collisions with Ar and Xe.

Science.gov (United States)

Ahu Akin, F; Ree, Jongbaik; Ervin, Kent M; Kyu Shin, Hyung

2005-08-08

The energetics and dynamics of collision-induced dissociation of O2- with Ar and Xe targets are studied experimentally using guided ion-beam tandem mass spectrometry. The cross sections and the collision dynamics are modeled theoretically by classical trajectory calculations. Experimental apparent threshold energies are 2.1 and 1.1 eV in excess of the thermochemical O2- bond dissociation energy for argon and xenon, respectively. Classical trajectory calculations confirm the observed threshold behavior and the dependence of cross sections on the relative kinetic energy. Representative trajectories reveal that the bond dissociation takes place on a short time scale of about 50 fs in strong direct collisions. Collision-induced dissociation is found to be remarkably restricted to the perpendicular approach of ArXe to the molecular axis of O2-, while collinear collisions do not result in dissociation. The higher collisional energy-transfer efficiency of xenon compared with argon is attributed to both mass and polarizability effects.

Threshold collision-induced dissociation of diatomic molecules: A case study of the energetics and dynamics of O2- collisions with Ar and Xe

International Nuclear Information System (INIS)

Ahu Akin, F.; Ree, Jongbaik; Ervin, Kent M.; Hyung, Kyu Shin

2005-01-01

The energetics and dynamics of collision-induced dissociation of O 2 - with Ar and Xe targets are studied experimentally using guided ion-beam tandem mass spectrometry. The cross sections and the collision dynamics are modeled theoretically by classical trajectory calculations. Experimental apparent threshold energies are 2.1 and 1.1 eV in excess of the thermochemical O 2 - bond dissociation energy for argon and xenon, respectively. Classical trajectory calculations confirm the observed threshold behavior and the dependence of cross sections on the relative kinetic energy. Representative trajectories reveal that the bond dissociation takes place on a short time scale of about 50 fs in strong direct collisions. Collision-induced dissociation is found to be remarkably restricted to the perpendicular approach of Ar/Xe to the molecular axis of O 2 - , while collinear collisions do not result in dissociation. The higher collisional energy-transfer efficiency of xenon compared with argon is attributed to both mass and polarizability effects

Understanding and modulating the high-energy properties of noble-gas hydrides from their long-bonding: an NBO/NRT investigation on HNgCO+/CS+/OSi+ and HNgCN/NC (Ng = He, Ar, Kr, Xe, Rn) molecules.

Science.gov (United States)

Zhang, Guiqiu; Song, Junjie; Fu, Lei; Tang, Kongshuang; Su, Yue; Chen, Dezhan

2018-04-18

The noble-gas hydrides, HNgX (X is an electronegative atom or fragment), represent potential high-energy materials because their two-body decomposition process, HNgX → Ng + HX, is strongly exoergic. Our previous studies have shown that each member of the HNgX (X = halogen atom or CN/NC fragment) molecules is composed of three leading resonance structures: two ω-bonding structures (H-Ng+ :X- and H:- Ng+-X) and one long-bonding structure (H∧X). The last one paints a novel [small sigma, Greek, circumflex]-type long-bonding picture. The present study focuses on the relationship between this novel bonding motif and the unusual energetic properties. We chose HNgCO+/CS+/OSi+/CN/NC, with the formula HNgAB (Ng = He, Ar, Kr, Xe, Rn; AB = CO+/CS+/OSi+/CN/NC) as the research system. We first investigated the bonding of HNgCO+ and its analogous HNgCS+/OSi+ species using NBO/NRT methods, and quantitatively compared the bonding with that in HNgCN/NC molecules. NBO/NRT results showed that each of the HNgCO+/CS+/OSi+ molecules could be better represented as a resonance hybrid of ω-bonding and long-bonding structures, but the long-bonding is much weaker than that in HNgCN/NC molecules. Furthermore, we introduced the long-bonding concept into the rationalization of the high-energy properties, and found a good correlation between the highly exothermic two-body dissociation channel and the long-bond order, bH-A. We also found that the long-bond order is highly tunable for these noble-gas hydrides due to its dependence on the nature of the electronegative AB fragments or the central noble-gas atoms, Ng. On the basis of these results, we could optimize the energetic properties by changing the long-bonding motif of our studied molecules. Overall, this study shows that the long-bonding model provides an easy way to rationalize and modulate the unusual energy properties of noble-gas hydrides, and that it is helpful to predict some noble-gas hydrides as potential energetic materials.

Photoionization studies with molecular beams

International Nuclear Information System (INIS)

Ng, C.Y.

1976-09-01

A molecular beam photoionization apparatus which combines the advantages of both the molecular beam method with photoionization mass spectrometry has been designed and constructed for carrying out some unique photoionization experiments. Rotational cooling during the supersonic expansion has resulted in high resolution photoionization efficiency curves for NO, ICl, C 2 H 2 and CH 3 I. The analysis of these spectra has yielded ionization potentials for these molecules to an accuracy of +- 3 MeV. Detailed autoionization structures were also resolved. This allows the investigation of the selection rules for autoionization, and the identification of the Rydberg series which converge to the excited states of the molecular ions. The degree of relaxation for thermally populated excited states has been examined using NO and ICl as examples. As a result of adiabatic cooling, a small percentage of dimers is also formed during the expansion. The photoionization efficiency curves for (NO) 2 , ArICl, Ar 2 , Kr 2 and Xe 2 have been obtained near the thresholds. Using the known dissociation energies of the (NO) 2 , Ar 2 , Kr 2 and Xe 2 van der Waals molecules, the corresponding dissociation energies for NO-NO + , Ar 2 + , Kr 2 + , and Xe 2 + have been determined. The ionization mechanisms for this class of molecules are examined and discussed

Multi-Column Experimental Test Bed for Xe/Kr Separation

International Nuclear Information System (INIS)

Greenhalgh, Mitchell Randy; Garn, Troy Gerry; Welty, Amy Keil; Lyon, Kevin Lawrence; Watson, Tony Leroy

2015-01-01

Previous research studies have shown that INL-developed engineered form sorbents are capable of capturing both Kr and Xe from various composite gas streams. The previous experimental test bed provided single column testing for capacity evaluations over a broad temperature range. To advance research capabilities, the employment of an additional column to study selective capture of target species to provide a defined final gas composition for waste storage was warranted. The second column addition also allows for compositional analyses of the final gas product to provide for final storage determinations. The INL krypton capture system was modified by adding an additional adsorption column in order to create a multi-column test bed. The purpose of this modification was to investigate the separation of xenon from krypton supplied as a mixed gas feed. The extra column was placed in a Stirling Ultra-low Temperature Cooler, capable of controlling temperatures between 190 and 253K. Additional piping and valves were incorporated into the system to allow for a variety of flow path configurations. The new column was filled with the AgZ-PAN sorbent which was utilized as the capture medium for xenon while allowing the krypton to pass through. The xenon-free gas stream was then routed to the cryostat filled with the HZ-PAN sorbent to capture the krypton at 191K. Selectivities of xenon over krypton were determined using the new column to verify the system performance and to establish the operating conditions required for multi-column testing. Results of these evaluations verified that the system was operating as designed and also demonstrated that AgZ-PAN exhibits excellent selectivity for xenon over krypton in air at or near room temperature. Two separation tests were performed utilizing a feed gas consisting of 1000 ppmv xenon and 150 ppmv krypton with the balance being made up of air. The AgZ-PAN temperature was held at 295 or 253K while the HZ-PAN was held at 191K for both

High-resolution measurements and multichannel quantum defect analysis of spectral line shapes of autoionizing Rydberg series

International Nuclear Information System (INIS)

Ueda, Kiyoshi

1997-01-01

Spectral line shapes for autoionizing Rydberg series are briefly reviewed within the framework of multichannel quantum defect theory (MQDT). Recent high-resolution measurements and MQDT analysis for the spectra line shapes are reviewed for the mp 5 ( 2 P 1/2 )ns ' and nd ' J=1 odd spectra of the Ar, Kr, and Xe atoms (m=3,4,5 for Ar, Kr, and Xe) and the 3p 5 ( 2 P 1/2 )nd ' J=2 and 3 odd spectra of Ar*3p 5 4p excited atoms. Some results are also discussed for the Ca 4p( 2 P 1/2,3/2 )ns and nd J=1 odd spectrum and the Ba 5d( 2 P 5/2 )nd J=1 odd spectrum

Charge-transfer cross sections of H+ ions in collisions with noble gas atoms in the energy range below 4.0 keV

International Nuclear Information System (INIS)

Kusakabe, Toshio; Sakaue, Hiroyuki A.; Tawara, Hiroyuki

2011-01-01

Charge-transfer cross sections in collisions of H + ions with the ground state He, Ar, Kr, and Xe atoms have been measured in the energy range below 4.0 keV with the initial growth rate method. These observed cross sections are also compared with previously published experimental data and theoretical predictions. In the He and Ar targets, it is found that some previous experimental data deviate significantly from the present observed cross sections as the collision energy decreases. It has been found that in the Kr and Xe targets, the energy dependence of the present observed cross sections behaves as “near-resonant” charge transfer. (author)

Study on decay of 118Xe and 119Xe by means of mass-separator on-line with a synchrocyclotron

International Nuclear Information System (INIS)

Berlovich, Eh.E.; Batist, L.Kh.; Blinnikov, Yu.S.

1976-01-01

The decay of sup(118, 119)Xe isotopes has been investigated. An experimental device involving a mass-separator operating in line with a synchrocyclotron is briefly outlined. The elements to be investigated were isolated from a proton-irradiated target by the 'on-beam-chemistry' methods and transferred into the mass-separator ion source. The Xe separated ions are transported to detectors in an experimental ha ll. The energies and relative γ ray intensities of 118 Xe → 118 J and of 119 Xe → 119 J decays ar presented. The error of the γ ray energy determination does not exceed 0.6 keV. Obtained are the periods of half-life: for 118 Xe - (3.8+-0.9) min, for 119 Xe - (5.8+-0.3) min. The decay scheme for 119 Xe is made up. The scheme of 119 Xe levels is well inscribed into the general systematics of the J odd isotope levels. On the basis of obtained and known data the spin values are described to the 119 J levels

Xe N4,5O-OOO satellite Auger spectrum

International Nuclear Information System (INIS)

Partanen, L; Huttula, M; Heinaesmaeki, S; Aksela, H; Aksela, S

2007-01-01

The N 4,5 O 1,2,3 -O 1,2,3 O 2,3 O 2,3 Auger transitions, appearing as a satellite structure in the N 4,5 -OO Auger spectrum of xenon, were studied in detail. By measuring the N 4,5 O-OOO satellite Auger spectrum both below and above the 4p ionization threshold, we were able to separate the satellite production via the direct photo-double ionization and the Auger cascade from the 4p states. The N 3 -N 4,5 O 2,3 Coster-Kronig transitions and the subsequent N 4,5 O 2,3 -O 2,3 O 2,3 O 2,3 satellite Auger transitions were calculated using the HF wavefunctions and the most intense satellite lines were assigned. The Xe N 4,5 O-OOO satellite spectrum was compared with the previously studied Kr M 4,5 N-NNN satellite Auger spectrum. The 5s orbital in Xe was found to reveal more pronounced electron correlation than the 4s orbital in Kr

Photoionization pathways and thresholds in generation of Lyman-α radiation by resonant four-wave mixing in Kr-Ar mixture

Directory of Open Access Journals (Sweden)

Oleg A. Louchev

2016-09-01

Full Text Available We develop a set of analytical approximations for the estimation of the combined effect of various photoionization processes involved in the resonant four-wave mixing generation of ns pulsed Lyman-α (L-α radiation by using 212.556 nm and 820-845 nm laser radiation pulses in Kr-Ar mixture: (i multi-photon ionization, (ii step-wise (2+1-photon ionization via the resonant 2-photon excitation of Kr followed by 1-photon ionization and (iii laser-induced avalanche ionization produced by generated free electrons. Developed expressions validated by order of magnitude estimations and available experimental data allow us to identify the area for the operation under high input laser intensities avoiding the onset of full-scale discharge, loss of efficiency and inhibition of generated L-α radiation. Calculations made reveal an opportunity for scaling up the output energy of the experimentally generated pulsed L-α radiation without significant enhancement of photoionization.

Photoionization pathways and thresholds in generation of Lyman-α radiation by resonant four-wave mixing in Kr-Ar mixture

Science.gov (United States)

Louchev, Oleg A.; Saito, Norihito; Oishi, Yu; Miyazaki, Koji; Okamura, Kotaro; Nakamura, Jumpei; Iwasaki, Masahiko; Wada, Satoshi

2016-09-01

We develop a set of analytical approximations for the estimation of the combined effect of various photoionization processes involved in the resonant four-wave mixing generation of ns pulsed Lyman-α (L-α ) radiation by using 212.556 nm and 820-845 nm laser radiation pulses in Kr-Ar mixture: (i) multi-photon ionization, (ii) step-wise (2+1)-photon ionization via the resonant 2-photon excitation of Kr followed by 1-photon ionization and (iii) laser-induced avalanche ionization produced by generated free electrons. Developed expressions validated by order of magnitude estimations and available experimental data allow us to identify the area for the operation under high input laser intensities avoiding the onset of full-scale discharge, loss of efficiency and inhibition of generated L-α radiation. Calculations made reveal an opportunity for scaling up the output energy of the experimentally generated pulsed L-α radiation without significant enhancement of photoionization.

Theoretical and experimental investigation of the triple-differential cross sections for electron-impact ionization of Kr(4p) and Xe(5p) at 1-keV impact energy

International Nuclear Information System (INIS)

Rasch, J.; Zitnik, M.; Avaldi, L.; Whelan, C.T.; Stefani, G.; Camilloni, R.; Allan, R.J.; Walters, H.R.

1997-01-01

The triple-differential cross sections for the ionization of Kr(4p) and Xe(5p) by a fast electron where the exiting electrons have energies of 20 eV and 1 keV have been measured and compared with distorted-wave Born calculations. Difficulties were encountered when trying to place the relative data on an absolute scale by extrapolation to the optical limit: an extensive study of this normalization process is presented and it is argued that it is not applicable to the heavier atoms considered here, but can be used effectively for helium targets. copyright 1997 The American Physical Society

Angļu valodas studentu tematiska vārdu krājuma bagātināšana ar datortehnoloģijas rīku palīdzību

OpenAIRE

Samčuka, Jeļena

2012-01-01

Maģistra darba mērķis bija izpētīt, vai ir iespējams uzlabot konkrētu vārdu apguvi, mācību procesā izmantojot datorprogrammu Quizlet. Pētījuma mērķa sasniegšanai tika aplūkotas teorijas par vārdu krājuma apguvi, tika izpētīta leksikas mācīšanās attīstība, kā arī dažādas pieejas, tai skaitā datorizētā apmācība vārdu krājuma apguvē. Tāpat tika analizēta arī pētnieku attieksme pret datora lietošanu leksikas apguves mācību procesā, kā arī datora izmantošanas priekšrocības un trūkumi. Lai stimulēt...

Melnās krāsas iespējas interjerā

OpenAIRE

Lapkovska, Ērika

2016-01-01

Diplomdarbā “Melnās krāsas iespējas interjerā”, analizējot pieejamo literatūru, tiek apskatīta melnās krāsas izpratne, nozīme un lietojums vēsturiskā skatījumā, kā arī melnās krāsas izmantojuma principi interjerā. Empīriskajā daļā tiek veikts salīdzinošais pētījums, analizējot dažādus kafejnīcu un bāru interjerus Latvijā un pasaulē, kuros ir melnās krāsas klātbūtne. Diplomdarba apjoms – 75 lpp., kurās iekļauts ievads, 4 nodaļas, 7 apakšnodaļas, literatūras saraksts ar 53 vienībām, 2 pielikum...

High-efficiency generation of pulsed Lyman-α radiation by resonant laser wave mixing in low pressure Kr-Ar mixture.

Science.gov (United States)

Saito, Norihito; Oishi, Yu; Miyazaki, Koji; Okamura, Kotaro; Nakamura, Jumpei; Louchev, Oleg A; Iwasaki, Masahiko; Wada, Satoshi

2016-04-04

We report an experimental generation of ns pulsed 121.568 nm Lyman-α radiation by the resonant nonlinear four-wave mixing of 212.556 nm and 845.015 nm radiation pulses providing a high conversion efficiency 1.7x10-3 with the output pulse energy 3.6 μJ achieved using a low pressure Kr-Ar mixture. Theoretical analysis shows that this efficiency is achieved due to the advantage of using (i) the high input laser intensities in combination with (ii) the low gas pressure allowing us to avoid the onset of full-scale discharge in the laser focus. In particular, under our experimental conditions the main mechanism of photoionization caused by the resonant 2-photon 212.556 nm radiation excitation of Kr atoms followed by the 1-photon ionization leads to ≈17% loss of Kr atoms and efficiency loss only by the end of the pulse. The energy of free electrons, generated by 212.556 nm radiation via (2 + 1)-photon ionization and accelerated mainly by 845.015 nm radiation, remains during the pulse below the level sufficient for the onset of full-scale discharge by the electron avalanche. Our analysis also suggests that ≈30-fold increase of 845.015 nm pulse energy can allow one to scale up the L-α radiation pulse energy towards the level of ≈100 μJ.

Low-lying level structure of 73Kr

International Nuclear Information System (INIS)

Moltz, D.M.; Robertson, J.D.; Norman, E.B.; Burde, J.; Beausang, C.W.

1993-01-01

We have used the 40 Ca( 36 Ar, 2pn) reaction to study the low-lying level structure of 73 Kr. By utilizing a bombarding energy at the Coulomb barrier, the relative cross section for this channel was enhanced to a few percent of the total reaction cross section. Levels in 73 Kr were assigned based primarily upon observed neutron-gamma-gamma coincidences and upon comparisons of these newly assigned transition cross sections with those from known nuclei. (orig.)

The mechanism of domain-wall structure formation in Ar-Kr submonolayer films on graphite

Directory of Open Access Journals (Sweden)

A. Patrykiejew

2014-12-01

Full Text Available Using Monte Carlo simulation method in the canonical ensemble, we have studied the commensurate-incommensurate transition in two-dimensional finite mixed clusters of Ar and Kr adsorbed on graphite basal plane at low temperatures. It has been demonstrated that the transition occurs when the argon concentration exceeds the value needed to cover the peripheries of the cluster. The incommensurate phase exhibits a similar domain-wall structure as observed in pure krypton films at the densities exceeding the density of a perfect (√3x√3R30º commensurate phase, but the size of commensurate domains does not change much with the cluster size. When the argon concentration increases, the composition of domain walls changes while the commensurate domains are made of pure krypton. We have constructed a simple one-dimensional Frenkel-Kontorova-like model that yields the results being in a good qualitative agreement with the Monte Carlo results obtained for two-dimensional systems.

Monolayer Adsorption of Ar and Kr on Graphite: Theoretical Isotherms and Spreading Pressures

Science.gov (United States)

Mulero; Cuadros

1997-02-01

The validity of analytical equations for two-dimensional fluids in the prediction of monolayer adsorption isotherms and spreading pressures of rare gases on graphite is analyzed. The statistical mechanical theory of Steele is used to relate the properties of the adsorbed and two-dimensional fluids. In such theory the model of graphite is a perfectly flat surface, which means that only the first order contribution of the fluid-solid interactions are taken into account. Two analytical equations for two-dimensional Lennard-Jones fluids are used: one proposed by Reddy-O'Shea, based in the fit on pressure and potential energy computer simulated results, and other proposed by Cuadros-Mulero, based in the fit of the Helmholtz free energy calculated from computer simulated results of the radial distribution function. The theoretical results are compared with experimental results of Constabaris et al. (J. Chem. Phys. 37, 915 (1962)) for Ar and of Putnam and Fort (J. Phys. Chem. 79, 459 (1975)) for Kr. Good agreement is found using both equations in both cases.

Electron capture into the 3s, 3p, 3d states and the 3, 4, 5, 6 levels of H by proton impact on gases

International Nuclear Information System (INIS)

Lenormand, J.

1976-01-01

The excitation of the Hsub(α), Hsub(β), Hsub(γ), Hsub(delta) Balmer lines by means of 15-85keV protons incident on noble-gas and molecular targets have been observed. Absolute cross-sections for electron capture by the 3l (l=s, p, d) states and the 3, 4, 5, 6 levels of hydrogen atom have been determined with He, Ne, Ar, Kr, Xe, N 2 and O 2 . Polarizations of the Hsub(α) and Hsub(β) lines have been measured for 10-70keV protons on Ar, Kr, and Xe. Absolute cross-sections for the emission of the 3914A band of N 2 + have been obtained for 10-100keV protons on the gaseous nitrogen target [fr

Photoionization studies with molecular beams

Energy Technology Data Exchange (ETDEWEB)

Ng, C.Y.

1976-09-01

A molecular beam photoionization apparatus which combines the advantages of both the molecular beam method with photoionization mass spectrometry has been designed and constructed for carrying out some unique photoionization experiments. Rotational cooling during the supersonic expansion has resulted in high resolution photoionization efficiency curves for NO, ICl, C/sub 2/H/sub 2/ and CH/sub 3/I. The analysis of these spectra has yielded ionization potentials for these molecules to an accuracy of +- 3 MeV. Detailed autoionization structures were also resolved. This allows the investigation of the selection rules for autoionization, and the identification of the Rydberg series which converge to the excited states of the molecular ions. The degree of relaxation for thermally populated excited states has been examined using NO and ICl as examples. As a result of adiabatic cooling, a small percentage of dimers is also formed during the expansion. The photoionization efficiency curves for (NO)/sub 2/, ArICl, Ar/sub 2/, Kr/sub 2/ and Xe/sub 2/ have been obtained near the thresholds. Using the known dissociation energies of the (NO)/sub 2/, Ar/sub 2/, Kr/sub 2/ and Xe/sub 2/ van der Waals molecules, the corresponding dissociation energies for NO-NO/sup +/, Ar/sub 2//sup +/, Kr/sub 2//sup +/, and Xe/sub 2//sup +/ have been determined. The ionization mechanisms for this class of molecules are examined and discussed.

Electron scattering by Ne, Ar and Kr at intermediate and high energies, 0.5-10 keV

Energy Technology Data Exchange (ETDEWEB)

Garcia, G.; Roteta, M.; Manero, F. [Centro de Investigaciones Energeticas Medioambientales y Tecnologicas (CIEMAT), Departamento de Fusion y Particulas Elementales, Madrid (Spain); Blanco, F. [Universidad Complutense de Madrid, Facultad de Fisica, Departamento de Fisica Atomica Molecular y Nuclear, Madrid (Spain); Williart, A. [Universidad Nacional de Educacion a Distancia, Facultad de Ciencias, Departamento de Fisica de los Materiales, Madrid (Spain)

1999-04-28

Semi-empirical total cross sections for electron scattering of noble gases (Ne, Ar and Kr) in the energy range 0.5-10 keV have been obtained by combining transmission-beam measurements for impact energies up to 6 keV with an asymptotic behaviour at higher energies according to the Born-Bethe approximation. The influence of the forward electron scattering on the experimental system has been evaluated by means of a Monte Carlo electron transport simulation. Theoretical values have also been obtained by applying the Born approximation in the case of inelastic processes and by means of an atomic scattering potential for the elastic part. The results of these calculations show an excellent agreement with the semi-empirical values in the above-mentioned energy range. (author)

Recoil-ion fractions in collisions of keV Ar sup + and Kr sup + ions with clean and adsorbate covered GaAs(1 1 0) surfaces

CERN Document Server

Gayone, J E; Grizzi, O; Vergara, L I; Passeggi, M C G; Vidal, R; Ferron, J

2002-01-01

Ion scattering and recoiling spectroscopy with time of flight analysis is used to study the ion fractions of Ga and As atoms recoiled in collisions of 5 keV Ar sup + and Kr sup + with clean GaAs(1 1 0) and with GaAs(1 1 0) covered with H, alkali metals (K and Cs) and fluorides (AlF sub 3). For the case of the clean surface, the Ga ion fraction is positive, large (approx 50%) and independent of the projectile type. The As ion fraction is also positive, low for Ar sup + (<10%) and relatively large (25%) for Kr sup + projectiles. The adsorption of H produces slight changes in both the As and Ga ion fractions, which is in agreement with the adsorption model where H reacts with both As and Ga atoms. The adsorption of alkalis produces strong changes in the ion fractions. At the beginning of the alkali adsorption the neutralization of Ga recoils increases fast with the coverage and follows approximately the variation of the work function. At coverages above half of the saturation value, where the work function ha...

Optical imaging of the boreholes KR29, KR29B, KR30, KR31, KR31B, KR32, KR33 and KR33B, at Olkiluoto 2005

International Nuclear Information System (INIS)

Majapuro, J.

2006-02-01

Suomen Malmi Oy conducted optical imaging surveys of the boreholes KR29, KR29B, KR30, KR31, KR31B, KR32, KR33 and KR33B at the Olkiluoto site in Eurajoki during June 2005. The survey is a part of Posiva Oy's detailed investigation program for the final disposal of spent nuclear fuel. The assignment included the field work and preliminary processing of the images. The report describes the field operation, equipment as well as processing procedures and shows the obtained results and their quality through example images. The raw and processed data are delivered digitally in WellCAD format. The images are also attached to the appendix CD of this report in Adobe Acrobat PDF-format. (orig.)

Interaction of Ne(2p54p), Ar(3p54p) and Kr(4p55p) excited atoms with He and Ne atoms. Processes of collisional depolarization

International Nuclear Information System (INIS)

Zagrebin, A.L.; Lednev, M.G.

1990-01-01

Quasimolecular terms Ne(2p 5 4p)+He, Ar(3p 5 4p)+He,Ne and Kr(4p 5 5p)+He,Ne are calculated within the framework of one-configuration method of effective Hamiltonian. The results of calculations agree with the experimental data

Direct measurements of methoxy removal rate constants for collisions with CH4, Ar, N2, Xe, and CF4 in the temperature range 673--973K

International Nuclear Information System (INIS)

Wantuck, P.J.; Oldenborg, R.C.; Baugchum, S.L.; Winn, K.R.

1988-01-01

Removal rate constants for CH 3 O by CH 4 , Ar, N 2 , Xe, and CF 4 were measured over a 400K temperature range using a laser photolysis/laser-induced fluorescence technique. Rapid methoxy removal rates are observed for the non-reactive collision partners (Ar, N 2 , Xe, and CF 4 ) at elevated temperatures showing that the dissociation and isomerization channels for CH 3 O are indeed important. The total removal rate constant (reaction /plus/ dissociation and/or isomerization) for CH 4 exhibits a linear dependence on temperature and has a removal rate constant, k/sub r/ /equals/ (1.2 +- 0.6) /times/ 10/sup /minus/8/exp[(/minus/101070 +- 350)/T]cm 3 molecule/sup /minus/1/s/sup /minus/1/. Assuming that the removal rate constant due to dissociation and/or isomerization are similar for CH 4 and CF 4 , the reaction rate constant for CH 3 O /plus/ CH 4 is equal to (1.7 +- 1.0) /times/ 10/sup /minus/10/exp[(/minus/7480 +- 1100)/T]cm 3 molecule/sup /minus/1/s/sup /minus/1/. 7 refs., 4 figs

Mantle Noble Gas Contents Controlled by Subduction of Serpentinite

Science.gov (United States)

Krantz, J. A.; Parman, S. W.; Kelley, S. P.; Smye, A.; Jackson, C.

2017-12-01

Geochemical analyses of exhumed subduction zone material1, well gases2, MORB, and OIBs3 indicate that noble gases are being recycled from the surface of the earth into the mantle. However, the path taken by these noble gases is unclear. To estimate the distribution and quantity of Ar, Kr, and Xe in subducting slabs, a model consisting of layers of sediments, altered oceanic crust (AOC), and serpentinite (hydrously altered mantle) has been developed. The noble gas contents of sediments and AOC were calculated using the least air-like and most gas-rich analyses from natural systems4,5, while serpentinite was modelled using both data from natural systems1 and experimentally determined solubilities. Layer thicknesses were assessed over a range of values: 1 to 12 km of sediments, 5 to 9 km of AOC, and 1 to 30 km of serpentinite. In all cases, the serpentinite layer contains at least an order of magnitude more Ar and Kr than the other layers. For realistic layer thicknesses (1 km of sediments, 6 km of AOC, and 3 km of serpentinite), Xe is distributed roughly equally between the three layers. By incorporating global subduction rates6, fluxes of the heavy noble gases into the mantle have been calculated as 4 · 1012 mol/Ma for 36Ar, 6 · 1011 mol/Ma for 84Kr, and 8 · 109 mol/Ma for 130Xe. These fluxes are equivalent to the total 84Kr and 130Xe contents of the depleted and bulk mantle over 1 and 10 Ma7. Similarly, the flux of 36Ar is equivalent over 1 and 100 Ma. Since the Kr and Xe have not been completely overprinted by recycling, the large majority of subducted noble gases must escape in the subduction zone. However, even the small amounts that are subducted deeper have affected the mantle as measured in both MORB and OIBs. 1. Kendrick, M.A. et al., Nature Geoscience, 4, 807-812, 2011 2. Holland, G. and Ballentine, C.J., Nature, 441, 186-191, 2006 3. Parai, R. and Mukhopadhyay, S., G3, 16, 719-735, 2015 4. Matsuda, J. and Nagao, K., Geochemical Journal, 20, 71-80, 1986

Monitoring measurements by difference flow method during the year 2006, drillholes OL-KR1, KR2, KR4, KR7, KR8, KR10, KR14, KR22, KR22B, KR27 and KR28

International Nuclear Information System (INIS)

Vaeisaesvaara, J.; Poellaenen, J.; Sokolnicki, M.

2008-04-01

The Posiva Flow Log/Difference Flow Method can be used for a relatively fast determination of water conductivity and hydraulic head in fractures/fractured zones in cored drillholes. In this method, a flow meter with a flow guide is used. This report presents the principles and results of the measurements carried out in drillholes OL-KR1, -KR2, -KR4, -KR7, -KR8, -KR10, -KR14, -KR22, -KR22B, -KR27 and -KR28 at the Olkiluoto investigation site during the year 2006. These measurements are a part of the Olkiluoto monitoring programme. Two different section lengths (2 m and 0.5 m) were used in the flow logging measurements. The flow into the drillhole or from the drillhole into the bedrock was measured within the section. Measurements were carried out both in natural conditions and when the drillhole was pumped. The transmissivity (T) and hydraulic head (h) of zones were calculated and are presented in the results. The measurement device also includes a sensor for single-point resistance (SPR) measurements. SPR was always measured in connection with flow measurements. SPR is measured when the tool is moving. The electric conductivity of fracture-specific water (EC) was measured in selected fractures in some of the drillholes. The fractures were chosen on the basis of the measured flow from the fracture to the drillhole. In addition to this some previously selected fractures were measured. The EC of the drillhole water was measured separately. (orig.)

Excess Gibbs energy for six binary solid solutions of molecularly simple substances

Energy Technology Data Exchange (ETDEWEB)

Lobo, L J; Staveley, L A.K.

1985-01-01

In this paper we apply the method developed in a previous study of Ar + CH/sub 4/ to the evaluation of the excess Gibbs energy G /SUP E.S/ for solid solutions of two molecularly simple components. The method depends on combining information on the excess Gibbs energy G /SUP E.L/ for the liquid mixture of the two components with a knowledge of the (T, x) solid-liquid phase diagram. Certain thermal properties o the pure substances are also needed. G /SUP E.S/ has been calculated for binary mixtures of Ar + Kr, Kr + CH/sub 4/, CO + N/sub 2/, Kr + Xe, Ar + N/sub 2/, and Ar + CO. In general, but not always, the solid mixtures are more non-ideal than the liquid mixtures of the same composition at the same temperature. Except for the Kr + CH/sub 4/ system, the ratio r = G /SUP E.S/ /G /SUP E.L/ is larger the richer the solution in the component with the smaller molecules.

Rapid monitoring of gaseous radionuclides using a portable spectrometer

International Nuclear Information System (INIS)

Chung, C.; Tsai, C.H.

1995-01-01

A field gamma ray spectrometer, consisting of a portable high purity germanium detector, portable multichannel analyser, and a notebook computer, was used to conduct in situ rapid scanning of radioactive Ar, Kr and Xe isotopes in the air around a nuclear facility. The portable gamma ray spectrometer was calibrated using Ar, Kr, and Xe radioisotopes, activated in a research reactor and released in a sealed chamber. The unit was further tested inside the reactor containment to monitor the concentration of 41 Ar. In a typical one hour field measurement, the detection limits for some rare gas radionuclides corresponded to dose rates around 0.1 nSv.h -1 , which is far less than the dose rate induced by derived air concentrations imposed by the authority. The dose rate due to ground level concentrations of gaseous radionuclides dispersed from a source, such a nuclear facility or nuclear test, can be monitored in a short period using the portable unit. (Author)

Experimental investigation of the chemistry of excited states of rare gases. Technical progress report, October 15, 1975--July 15, 1976

International Nuclear Information System (INIS)

Setser, D.W.

1976-07-01

Total quenching rate constants and branching ratios for rare gas halide excimer formation have been measured for Ar( 3 P 0 , 2 ), Kr( 3 P 2 ) and Xe( 3 P 2 ) reacting with chlorine and fluorine-containing molecules. Emphasis was focused on systems giving KrF* and XeF* as products. All halogen containing molecules quench metastable rare gas atoms with gas kinetic cross-sections. However, only diatomic halogens and small molecules with O-X or N-X bonds quench the metastable with high branching ratios for excimer formation. The product channels for the reagents which do not yield the rare gas halides as the main exit channel remain to be identified. The work that has been done provides a good survey of halogen donors. This work will assist in selection of the best halogen-containing molecules for use in rare gas halide excimer lasers. Tunable dye laser fluorescence experiments have been done to obtain radiative lifetimes and two body quenching rate constants (with ground state Ar) for excited states of Ar*(3p 5 ,4p) and Ar*

Experimental study of the slowing down of heavy ions at 20 to 100 MeV per nucleon in matter

International Nuclear Information System (INIS)

Herault, J.

1988-01-01

The measurements of typical parameters on heavy ions penetration through matter presented in this work have been performed at the GANIL accelerator facility, using the LISE magnetic spectrometer from 20 to 100 MeV per nucleon. Two magnetic optical configurations of the spectrometer LISE corresponding respectively to energy and angle analysis, have been used. In the first configuration, the analysis of the energy loss distribution, caused by the interaction of the heavy ions beam with the target material, permit to determine the stopping power and the energy straggling. The stopping power is defined experimentally by the ratio of the average energy loss in the target to the thickness of this one. This quantity has been measured for a set of heavy ions ( 17 O, 40 Ar, 86 Kr and 132 Xe) in gaseous media (H 2 , He, N 2 , Ne, Ar, Kr, Xe, CH 4 , C 4 H 10 , CO 2 and CF 4 ) and compared to semi-empirical tabulations. These determinations are compared to those obtained in solid media to study the evolution of the solid-gas difference. This effect vanishes progressively when the projectile tends to be totally stripped (the charge state becomes identical to the atomic number). The heavy ion energy distributions at the exit of degraders and particularly their full width at half maximum have been measured for various projectiles ( 16 O, 40 Ar, 84 Kr, 86 Kr, 100 Mo and 132 Xe) in solid (Be, C, Al, Si, Ti, Ni, Cu, Ag, Ta, Au and Mylar) and gaseous media (the same as for stopping power determinations). A significant contribution of charge exchange straggling to the energy loss straggling is observed for partially stripped ions. A second optical configuration of the beam line LISE has been used, to obtain an image of heavy ions beams passing through targets for various heavy ions ( 16 O, 17 O, 40 Ar, 86 Kr and 100 Mo) in gaseous and solid media. The scaling law for angular straggling is confirmed and extended over five orders of magnitude [fr

Observation of surface excitons in rare gas solids

International Nuclear Information System (INIS)

Saile, V.; Skibowski, M.; Steinmann, W.; Guertler, P.; Koch, E.E.; Kozevnikov, A.

1976-04-01

Evidence is obtained for the excitation of surface excitons in solid Ar, Kr and Xe in optical transmission and reflection experiments using synchrotron radiation. They are located at photon energies ranging from 0.6 eV for Ar to 0.1 eV for Xe below the corresponding bulk excitons excited from the valence bands. Their halfwidths (20-50 MeV) is less than half the values found for the bulk excitons. Some are split by an amount considerably smaller than the spin orbit splitting of the valence bands. (orig.) [de

New spectroscopic results in Xe II, Xe III, and Xe IV

OpenAIRE

Reyna Almandos, Jorge Guillermo; Gallardo, Mario; Garavaglia, Mario J.

1982-01-01

New results obtained in spontaneous xenon spectrum employing a conventional pulsed gaseous laser tube as light source, are presented in this work. A total of 626 spectral lines has been ionically assigned as follows: 50 to Xe II spectrum, 103 to Xe III spectrum, arid 222 to Xe IV spectrum. 30 Lines previously assigned to Xe II were reassigned as belonging to Xe III, 94 lines were assigned with some doubts to Xe II-III spectrum and 84 lines to Xe Ill-IV spectrum. Also there were clas...

Parametric sensitivity analysis for the helium dimers on a model potential

Directory of Open Access Journals (Sweden)

Nelson Henrique Teixeira Lemes

2012-01-01

Full Text Available Potential parameters sensitivity analysis for helium unlike molecules, HeNe, HeAr, HeKr and HeXe is the subject of this work. Number of bound states these rare gas dimers can support, for different angular momentum, will be presented and discussed. The variable phase method, together with the Levinson's theorem, is used to explore the quantum scattering process at very low collision energy using the Tang and Toennies potential. These diatomic dimers can support a bound state even for relative angular momentum equal to five, as in HeXe. Vibrational excited states, with zero angular momentum, are also possible for HeKr and HeXe. Results from sensitive analysis will give acceptable order of magnitude on potentials parameters.

Josephinite. A terrestrial alloy with radiogenic xenon-129 and the noble gas imprint of iron meteorites

Energy Technology Data Exchange (ETDEWEB)

Downing, R G; Hennecke, E W; Manuel, O K [Missouri Univ., Rolla (USA). Dept. of Chemistry

1977-12-01

Analyses of noble gases released by stepwise heating of Josephinite reveal two radiogenic components, radiogenic /sup 129/Xe asymptotically equals 1 x 10/sup -12/ ccSTP/g and radiogenic /sup 40/Ar asymptotically equals 1 x 10/sup -6/ cc STP/g, and the following components of trapped noble gases: He with /sup 3/He//sup 4/He asymptotically equals 4 x 10/sup -5/, Ne with /sup 20/Ne//sup 22/Ne=10.5, Ar with /sup 40/Ar//sup 36/Ar=3 x 10/sup 2/, and Kr and Xe with isotopic compositions similar to those observed in iron meteorites. The excess of /sup 40/Ar and literature values of K in bulk Josephinite yield and apparent K-Ar age of asymptotically equals 4.6 x 10/sup 9/ years.

Matrix-isolation and ab initio study of HKrCCCl and HXeCCCl

Energy Technology Data Exchange (ETDEWEB)

Zhu, Cheng; Räsänen, Markku; Khriachtchev, Leonid, E-mail: leonid.khriachtchev@helsinki.fi [Department of Chemistry, University of Helsinki, P.O. Box 55, FI-00014 Helsinki (Finland)

2015-12-28

We report on two new noble-gas molecules, HKrCCCl and HXeCCCl, prepared in low-temperature Kr and Xe matrices. These molecules are made by UV photolysis of HCCCl in the matrices and subsequent thermal annealing. The HCCCl precursor is produced by microwave discharge of a mixture of a matrix gas with trichloroethylene (HClC=CCl{sub 2}). The assignments of the new noble-gas molecules are supported by deuteration experiments and quantum chemical calculations at the MP2(full) and CCSD(T) levels of theory with the def2-TZVPPD basis set. No evidence of ClXeCCH, which is computationally reliably stable, is found in the experiments. ClKrCCH as well as the Ar compounds HArCCCl and ClArCCH are not observed either, which is in agreement with the calculations.

Origin of planetary primordial rare gas - The possible role of adsorption.

Science.gov (United States)

Fanale, F. P.; Cannon, W. A.

1972-01-01

The degree of physical adsorption of Ne, Ar, Kr, and Xe on pulverized samples of the Allende meteorite at 113 K has been measured. The observed pattern of equilibrium enrichment of heavy rare gases over light on the pulverized meteorite surfaces relative to the gas phase is similar to the enrichment pattern exhibited by planetary primordial rare gas when compared with the composition of solar rare gas. Results indicate that, at 113 K, a total nebular pressure of from .01 to .001 atm would be required to explain the Ar, Kr, and Xe abundances in carbonaceous chondrites with an adsorption mechanism. This pressure estimate is compatible with the range of possible nebular pressures suggested by astrophysical arguments. However, the subsequent mechanism by which initially adsorbed gas might have been transferred into the interiors of grains cannot be identified at present.

Decay kinetics of Krsup(*) levels populated by ArF laser radiation

International Nuclear Information System (INIS)

Wren, D.J.; Setser, D.W.

1981-01-01

The Kr 6p [3/2] 2 (or 3p 6 ) level was pumped via a two-photon absorption using a focused ArF laser (193 nm). The time dependent fluorescence from excited Kr levels was observed using a monochromator and photomultiplier tube and transient digitizer. Fluorescence from the pumped level, observed via the 3p 6 → 1s 5 transition, has a lifetime of 8 +- 2 ns independent of the Kr pressure (2-30 Torr). Fluorescence from other levels of the Kr (4p 5 6p) manifold was either unobserved or weak. Strong fluorescence was observed from the Kr (4p 5 5p) levels via transitions to the Kr (4p 5 5s) levels, the highest populated levels being 2p 6 , 2p 8 and 2p 9 . All Kr (4p 5 5p) levels display effective lifetimes much longer than the radiative lifetimes; effective zero pressure lifetimes for Kr 2p 3 , 2p 6 and 2p 7 are 72 +- 15, 66 +- 15 and 90 +- 15 ns, respectively. The short lifetime of the Kr (3p 6 ) level is explained by very fast collisional depopulation by photoelectrons produced in three photon ionization of Kr by the ArF laser. The Kr (4p 5 5p) levels are populated indirectly from the Kr (3p 6 ) level and the long lifetimes of the Kr (4p 5 5p) levels represent the lifetime of the intermediate state (or states) which lead to the Kr (4p 5 5p) levels. Strong possibilities for the intermediate states are the Kr (4p 5 4d) levels. (orig.)

Geophysical borehole logging of the boreholes KR30, KR31, KR31b, KR32, KR33, KR33b and KR24 Upper Part, at Olkiluoto 2005

International Nuclear Information System (INIS)

Majapuro, J.

2005-12-01

Suomen Malmi Oy conducted geophysical borehole logging of the boreholes KR30, KR31, KR31B, KR32, KR33, KR33B and KR24 upper part at the Olkiluoto site in Eurajoki during December 2004, January, February and September 2005. The survey is a part of Posiva Oy's detailed investigation program for the final disposal of spent nuclear fuel. The assignment included the field work and processing of the acoustic data. The report describes the field operation, equipment as well as processing procedures and shows the obtained results and their quality in the appendices. The raw and processed data are delivered digitally in WellCAD and Excel format. (orig.)

Geophysical borehole logging of the boreholes KR30, KR31, KR31b, KR32, KR33, KR33b and KR24 Upper Part, at Olkiluoto 2005

Energy Technology Data Exchange (ETDEWEB)

Majapuro, J. [Suomen Malmi Oy, Espoo (Finland)

2005-12-15

Suomen Malmi Oy conducted geophysical borehole logging of the boreholes KR30, KR31, KR31B, KR32, KR33, KR33B and KR24 upper part at the Olkiluoto site in Eurajoki during December 2004, January, February and September 2005. The survey is a part of Posiva Oy's detailed investigation program for the final disposal of spent nuclear fuel. The assignment included the field work and processing of the acoustic data. The report describes the field operation, equipment as well as processing procedures and shows the obtained results and their quality in the appendices. The raw and processed data are delivered digitally in WellCAD and Excel format. (orig.)

Anomalous krypton in the Allende meteorite

Science.gov (United States)

Frick, U.

1977-01-01

The reported investigation provides important new data for the heavy noble gases, especially Kr, in the Allende meteorite. The data are used to criticize the original model of Lewis et al. (1975) based on the noble gas data of these researchers. The conclusions reached in the investigation support alternative models which have been mainly based on Xe data by Lewis et al. (1975, 1977). Because of the relatively high noble gas abundances in the separates studied, disturbance from nuclear effects occurring in situ such as spallation and neutron capture is insignificant, offering an opportunity to study primordial Ar, Kr, and Xe. The isotopic and abundance data obtained from the samples largely confirm the noble gas results of Lewis et al. (1975, 1977) where isotopic correlations agree with the correlations of the considered samples. It is found that both Kr and Xe data are consistent with a two component mixture of 'ordinary' as well as 'anomalous' planetary gases.

Geophysical drillhole logging and optical imaging of the drillholes OL-KR43, OL-KR44, OL-KR44B, OL-KR45, OL-KR45B, OL-KR46, OL-KR46B, OL-KR47, OL-KR47B and OL-KR48, at Olkiluoto 2007 and 2008

International Nuclear Information System (INIS)

Tarvainen, A.-M.; Heikkinen, E.

2008-09-01

Suomen Malmi Oy conducted geophysical drillhole logging and optical imaging of the drillholes OL-KR43, OL-KR44, OL-KR44B, OL-KR45, OL-KR45B, OL-KR46, OL-KR46B, OL-KR47, OL-KR47B and OL-KR48 at the Olkiluoto site in Eurajoki during December 2007, May 2008. The survey is a part of Posiva Oy's detailed investigation program for the final disposal of spent nuclear fuel. The assignment included the field work and data processing. The report describes field operation, equipment as well as processing procedures and shows the obtained results and an analysis of their quality in the appendices. The raw and processed data are delivered digitally in WellCAD, PDF and Excel format. (orig.)

Production de vapeur d'uranium par pulverisation cathodique dans une cathode creuse: efficacites relatives des gaz Ne, Ar, Kr et concentration a l'etat 5L06

International Nuclear Information System (INIS)

Gagne, J.M.; Mongeau, B.; Leblanc, B.; Saint-Dizier, J.P.; Pianarosa, P.; Bertrand, L.

1978-01-01

We have investigate the production of uranium vapors in the 5 L 0 6 ground state using a sputtering technique. We have also compared the performance of the Ne, Ar, Kr gases as carrier agents. We have found that the krypton gas gives a maximum yield with minimum energy. Finally the density of U vapors has been found to be of the order of 10 12 atmos cm -3

Measurements of diameters of selectively etchable tracks produced in polymer by heavy ions

International Nuclear Information System (INIS)

Apel', P.Yu.

1981-01-01

The process of pore formation in polyethyleneterephtalate films irradiated by the 136 Xe, 84 Kr, 40 Ar ions was investigated by measuring the conductivity of the samples during etching. The diameters of the damaged tracks within which the local etching rate was larger than etching rate for non-destroyed polymer were determined. In the case of the 136 Xe ions measurements have been carried out at different ion energies [ru

Multiple Electron Stripping of Heavy Ion Beams

International Nuclear Information System (INIS)

Mueller, D.; Grisham, L.; Kaganovich, I.; Watson, R. L.; Horvat, V.; Zaharakis, K. E.; Peng, Y.

2002-01-01

One approach being explored as a route to practical fusion energy uses heavy ion beams focused on an indirect drive target. Such beams will lose electrons while passing through background gas in the target chamber, and therefore it is necessary to assess the rate at which the charge state of the incident beam evolves on the way to the target. Accelerators designed primarily for nuclear physics or high energy physics experiments utilize ion sources that generate highly stripped ions in order to achieve high energies economically. As a result, accelerators capable of producing heavy ion beams of 10 to 40 Mev/amu with charge state 1 currently do not exist. Hence, the stripping cross-sections used to model the performance of heavy ion fusion driver beams have, up to now, been based upon theoretical calculations. We have investigated experimentally the stripping of 3.4 Mev/amu Kr 7+ and Xe +11 in N2; 10.2 MeV/amu Ar +6 in He, N2, Ar and Xe; 19 MeV/amu Ar +8 in He, N2, Ar and Xe; 30 MeV He 1 + in He, N2, Ar and Xe; and 38 MeV/amu N +6 in He, N2, Ar and Xe. The results of these measurements are compared with the theoretical calculations to assess their applicability over a wide range of parameters

Ionization energies of Xe2+ and Xe3+

International Nuclear Information System (INIS)

Dutil, R.; Marmet, P.

1980-01-01

New electron impact measurements show that the previously accepted energies of ionization of Xe 2+ and Xe 3+ from xenon are erroneous. These energies are determined 33.11 +- 0.04 eV for Xe 2+ and 64.35 +- 0.10 eV for Xe 3+ . New structures are seen by electron impact just above the Xe 2+ threshold. New information is also given on the ionization energies of Xe 4+ and Xe 5+ . (orig.)

Z/sub 1/ dependence of ion-induced electron emission from aluminum. [H/sup +/,H/sub 2//sup +/,D/sup +/,D/sub 2//sup +/,He/sup +/,B/sup +/,C/sup +/,N/sup +/,N/sub 2//sup +/,O/sup +/,O/sub 2//sup +/,F/sup +/,Ne/sup +/,S/sup +/,Cl/sup +/,Ar/sup +/,Kr/sup +/, and Xe/sup +/, 1. 2-50 keV

Energy Technology Data Exchange (ETDEWEB)

Alonso, E.V.; Baragiola, R.A.; Ferron, J.; Jakas, M.M.; Oliva-Florio, A.

1980-07-01

We have measured the electron emission yields ..gamma.. of clean aluminum under bombardment with H/sup +/, H/sub 2/ /sup +/, D/sup +/, D/sub 2/ /sup +/, He/sup +/, B/sup +/, C/sup +/, N/sup +/, N/sub 2/ /sup +/, O/sup +/, O/sub 2/ /sup +/, F/sup +/, Ne/sup +/, S/sup +/, Cl/sup +/, Ar/sup +/, Kr/sup +/, and Xe/sup +/ in the energy range 1.2--50 keV. The clean surfaces were prepared by in situ evaporation of high-purity Al under ultra-high-vacuum conditions. It is found that kinetic electron emission yields ..gamma../sub k/, obtained after subtracting from the measured ..gamma.. a contribution due to potential emission, are roughly proportional to the electronic stopping powers, for projectiles lighter than Al. For heavier projectiles there is a sizable contribution to electron emission from collisions involving rapidly recoiling target atoms, which increases with the mass of the projectile, and which dominates the threshold and near-threshold behavior of kinetic emission. The results, together with recently reported data on Auger electron emission from ion-bombarded Al show that the mechanism proposed by Parilis and Kishinevskii of inner-shell excitation and subsequent Auger decay is negligible for light ions and probably small for heavy ions on Al and in our energy range. We thus conclude that kinetic electron emission under bombardment by low-energy ions results mainly from the escape of excited valence electrons.

Nuclear reaction studies

International Nuclear Information System (INIS)

Alexander, J.M.; Lacey, R.A.

1994-01-01

Research focused on the statistical and dynamical properties of ''hot'' nuclei formed in symmetric heavy-ion reactions. Theses included ''flow'' measurements and the mechanism for multifragment disassembly. Model calculations are being performed for the reactions C+C, Ne+Al, Ar+Sc, Kr+Nb, and Xe+La. It is planned to study 40 Ar reactions from 27 to 115 MeV/nucleon. 2 figs., 41 refs

Study of laser-generated debris free x-ray sources produced in a high-density linear Ar, Kr, Xe, Kr/Ar and Xe/Kr/Ar mixtures gas jets by 2 ω, sub-ps LLNL Titan laser

Science.gov (United States)

Kantsyrev, V. L.; Schultz, K. A.; Shlyaptseva, V. V.; Safronova, A. S.; Cooper, M. C.; Shrestha, I. K.; Petkov, E. E.; Stafford, A.; Moschella, J. J.; Schmidt-Petersen, M. T.; Butcher, C. J.; Kemp, G. E.; Andrews, S. D.; Fournier, K. B.

2016-10-01

The study of laser-generated debris-free x-ray sources in an underdense plasma produced in a high-density linear gas-puff jet was carried out at the LLNL Titan laser (2 ω, 45 J, sub-ps) with an intensity in the 10 um focal spot of 7 x 1019 W/cm2. A linear nozzle with a fast valve was used for the generation of a clusters/gas jet. X-ray diagnostics for the spectral region of 0.7 - 9 keV include: two spectrometers and pinhole cameras, and 3 groups of fast filtered detectors. Electron beams were measured with the EPPS magnetic spectrometer (>1 MeV) and Faraday cups (>72 keV). Spectralon/spectrometer devices were also used to measure absorption of laser radiation in the jets. New results were obtained on: anisotropic generation of x-rays (laser to x-ray conversion coefficient was >1%) and characteristics of laser-generated electron beams; evolution of x-ray generation with the location of the laser focus in a cluster-gas jet, and observations of a strong x-ray flash in some focusing regimes. Non-LTE kinetic modeling was used to estimate plasma parameters. UNR work supported by the DTRA Basic Research Award # HDTRA1-13-1-0033. Work at LLNL was performed under the auspices of the U.S. DOE by LLNL under Contract DE-AC52-07NA27344.

Dynamics of Chemical and Charge Transfer Reactions of Molecular Dications: Part V. An Experimental and Theoretical Study of Reactions between CHCl2+ and Ar, Kr and Xe

Czech Academy of Sciences Publication Activity Database

Roithová, Jana; Žabka, Ján; Thissen, R.; Herman, Zdeněk

2003-01-01

Roč. 5, - (2003), s. 2988-2995 ISSN 1463-9076 R&D Projects: GA ČR GA203/00/0632; GA AV ČR KJB4040302 Grant - others:Konktakt Barrande(XE) 2002-013-1 Institutional research plan: CEZ:AV0Z4040901 Keywords : charge-transfer * experimental and theoretical study * molecular dications Subject RIV: CF - Physical ; Theoretical Chemistry Impact factor: 1.959, year: 2003

Optical imaging of drillholes OL-KR40, OL-KR41, OL-KR41B, OL-KR42, OL-KR42B, OL-KR43 and OL-KR43B at Olkiluoto, 2006 and 2007

International Nuclear Information System (INIS)

Tarvainen, A.-M.

2007-03-01

Suomen Malmi Oy carried out optical imaging of drillholes OL-KR40, OL-KR41, OL-KR41B, OL-KR42, OL-KR42B, OL-KR43 and OL-KR43B at Olkiluoto site in Eurajoki during July, August, November and December 2006 as well as January 2007. The survey is a part of Posiva Oy's detailed investigation program for the final disposal of spent nuclear fuel. The assignment included the field work and the data processing. This report describes the field operation, the equipment as well as the processing procedures and shows the obtained results and their quality. The raw and processed data are delivered digitally in WellCAD and PDF format. (orig.)

Diverging effects of isotopic fractionation upon molecular diffusion of noble gases in water: mechanistic insights through ab initio molecular dynamics simulations.

Science.gov (United States)

Pinto de Magalhães, Halua; Brennwald, Matthias S; Kipfer, Rolf

2017-03-22

Atmospheric noble gases are routinely used as natural tracers to analyze gas transfer processes in aquatic systems. Their isotopic ratios can be employed to discriminate between different physical transport mechanisms by comparison to the unfractionated atmospheric isotope composition. In many applications of aquatic systems molecular diffusion was thought to cause a mass dependent fractionation of noble gases and their isotopes according to the square root ratio of their masses. However, recent experiments focusing on isotopic fractionation within a single element challenged this broadly accepted assumption. The determined fractionation factors of Ne, Ar, Kr and Xe isotopes revealed that only Ar follows the prediction of the so-called square root relation, whereas within the Ne, Kr and Xe elements no mass-dependence was found. The reason for this unexpected divergence of Ar is not yet understood. The aim of our computational exercise is to establish the molecular-resolved mechanisms behind molecular diffusion of noble gases in water. We make the hypothesis that weak intermolecular interactions are relevant for the dynamical properties of noble gases dissolved in water. Therefore, we used ab initio molecular dynamics to explicitly account for the electronic degrees of freedom. Depending on the size and polarizability of the hydrophobic particles such as noble gases, their motion in dense and polar liquids like water is subject to different diffusive regimes: the inter-cavity hopping mechanism of small particles (He, Ne) breaks down if a critical particle size achieved. For the case of large particles (Kr, Xe), the motion through the water solvent is governed by mass-independent viscous friction leading to hydrodynamical diffusion. Finally, Ar falls in between the two diffusive regimes, where particle dispersion is propagated at the molecular collision time scale of the surrounding water molecules.

Primordial Terrestrial Xe from the Viewpoint of CFF-Xe

Science.gov (United States)

Meshik, A. P.; Shukolyukov, Yu. A.; Jessberger, E. K.

1995-09-01

We have already reported [7, 23] on the non-linear isotope mass-fractionation of fission Xe by migration of the precursors I, Te, Sn, and Sb and simultaneous fission of heavy nuclei. Xe with anomalous isotopic pattern was found in a number of meteorites and terrestrial materials and was named CFF-Xe (Chemically Fractionated Fission Xe). It is characterized by an up eightfold ^132Xe and ^131Xe excesses coupled with smaller ^134Xe and ^129Xe excesses. The present work is aimed to estimate the role of CFF-Xe in the terrestrial lithosphere and specifically deals with the problem of the isotopic composition of primordial terrestrial Xe. Due to variations of the migration conditions the isotopic structure of CFF-Xe is not well established and is even not reproducible in the same rock [2]. Nevertheless, we have tried to estimate the composition of CFF-Xe by investigating all available isotopic data of Xe of presumable mantle origin. This is Xe in MORB [29, 1, 12] and ocean island glasses [1, 28], in diamonds [17], in volcanic rocks [29, 8, 9, 21], in volcanic glasses from pillow basalts [16, 6], continental igneous rocks [1, 24, 10, 22], carbonatites and granitoids [1] as well as Xe in natural gases [3, 24, 11, 4, 15]. All data are plotted Fig. 1 where we also suggest end members of the observed scattering. Optimized slopes of CFF-lines are shown as well as the position of the initial points which we regard as primordial terrestrial Xe (Xe0). The isotopic composition of CFF-Xe and Xe0 are given in Tab. 1. The abundances of ^124Xe and ^126Xe in mantle derived samples are very uncertain, but since ^128Xe/^130Xe in Xea and Xe0 is very similar we propose the same ^124Xe/^130Xe and ^126Xe/^130Xe ratios for both Xea and Xe0. If so, AVCC-Xe is simply Xe0 with an admixture of L-Xe, and atmospheric xenon Xea consists of Xe0, CFF-Xe and a small amount of fission Xe (92.5%Xe0 + 5.3%CFF-Xe + 2.2%XeF). Thus, a number of old problems in xenology are removed. The hypothetic components U-Xe

Electron detachment in ion-atom collisions

International Nuclear Information System (INIS)

Vreugd, C. de.

1980-01-01

The electron detachment process that occurs in negative ion-atom collisions is investigated. Differential cross sections were measured for the collisions of F - , Cl - , Br - , I - on He, Ne, Ar, Kr, Xe, Na and K. Electron energy distributions were obtained for some of the systems. (Auth.)

Configuration-interaction relativistic-many-body-perturbation-theory calculations of photoionization cross sections from quasicontinuum oscillator strengths

International Nuclear Information System (INIS)

Savukov, I. M.; Filin, D. V.

2014-01-01

Many applications are in need of accurate photoionization cross sections, especially in the case of complex atoms. Configuration-interaction relativistic-many-body-perturbation theory (CI-RMBPT) has been successful in predicting atomic energies, matrix elements between discrete states, and other properties, which is quite promising, but it has not been applied to photoionization problems owing to extra complications arising from continuum states. In this paper a method that will allow the conversion of discrete CI-(R)MPBT oscillator strengths (OS) to photoionization cross sections with minimal modifications of the codes is introduced and CI-RMBPT cross sections of Ne, Ar, Kr, and Xe are calculated. A consistent agreement with experiment is found. RMBPT corrections are particularly significant for Ar, Kr, and Xe and improve agreement with experimental results compared to the particle-hole CI method. As a result, the demonstrated conversion method can be applied to CI-RMBPT photoionization calculations for a large number of multivalence atoms and ions

Drillhole gamma-ray spectrum logging in drillholes OL-KR11, OL-KR44, OL-KR44B, OL-KR45B, OL-KR46, OL-KR47, OL-KR47B, OL-KR48 and ground survey at Olkiluoto in Eurajoki, 2007 and 2008

Energy Technology Data Exchange (ETDEWEB)

Julkunen, A.; Kallio, L.; Kuusisto, M. (Astrock Oy, Sodankylae (Finland))

2009-09-15

The aim of the detailed drillhole surveys is to increase the knowledge of the bedrock on the study area and to supplement the investigations made earlier. As a part of the detailed investigations Astrock Oy carried out drillhole spectrometer logging in drillholes OL-KR11, OL-KR44, OL-KR44B, OL-KR45B, OL-KR46, OL-KR47, OL-KR47B, OL-KR48 and ground survey at Olkiluoto site in Eurajoki during 2007 and 2008. This report describes the logging, data processing and the results. For the first time the results contains moving standard deviation calculations of Th/K ratio, because the variability of Th/K ratio is a reasonably good indicator of alteration zones. This report includes also moving standard deviation calculations of Th/K ratio from earlier measured and reported drillholes OL-KR40-43 and OL-KR40B-43B. (orig.)

40Ar/36Ar in MORB glasses: Constraints on atmosphere and mantle evolution

International Nuclear Information System (INIS)

Sarda, P.; Staudacher, T.; Allegre, C.J.; Paris-7 Univ., 75

1985-01-01

Argon isotopic composition measurements of MORB glassy samples from the Pacific, Atlantic and Indian Oceans are performed. There is a very large scatter in the 40 Ar/ 36 Ar ratio, from 980 up to 24,400 for bulk rock analyses, which is mainly due to atmospheric contamination: Using the stepwise heating technique, very high ratios are obtained, from 15,000 up to 25,250 which is the highest 40 Ar/ 36 Ar ratio ever measured in MORB. We establish a negative correlation between the highest 40 Ar/ 36 Ar results from stepwise heating and 87 Sr/ 86 Sr ratios, which is perfectly consistent with a two-layered mantle structure. From both 40 Ar and 129 Xe MORB systematics a model is proposed for the kinetics of degassing: a very early and extensive burst, with a time constant of approx.= 4 My, is followed by a slower process of present day type, with a time constant of approx.= 0.5 Gy. The mean age of the atmosphere is so determined to be around 4.4 Gy. (orig./WB)

Results of sampling and analysis of groundwater from multi-packered boreholes OL-KR1, OL-KR3, OL-KR5, OL-KR9, OL-KR11 and OL-KR12 at Olkiluoto, Eurajoki, in 2004

Energy Technology Data Exchange (ETDEWEB)

Hirvonen, H. [Teollisuuden Voima Oyj, Eurajoki (Finland); Hatanpaeae, E. [lnsinoeoeritoimisto Paavo Ristola Oy, Hollola (Finland)

2005-12-15

Nine groundwater samples were collected at Olkiluoto from deep multi-packered boreholes OL-KR1, OL-KR3, OL-KR5, OL-KR9, OL-KR11 and OL-KR12 between spring 2004 and the beginning of 2005. The aim of the ground water sampling was to get information for the basis of the monitoring program (OMO) during ONKALO construction. Sampling sections were mainly chosen so that the results of the chemical analyses from earlier studies could be used for comparison. This study presents the sampling methods and the results of the laboratory analyses of groundwater samples from the deep multi-packered boreholes OL-KR1 (151.2-156.8 m, 311.2-336.8 m and 524.4-528.4 m), OL-KR3 (242.6-253.2 m), OL-KR5 (277.2-284.6 m and 457.2-476.2 m), OL-KR9 (468.2-482.2 m), OL-KR11 (597.5-628.1 m) and OLKR12 (363-368 m). The analytical results of the groundwater samplings are compared to earlier analytical results. According to Davis and De Wiest's (1967) classification, the collected groundwater samples represent either the borehole water type Na-Cl (OL-KR1/T/151.2-156.8 m, OLK-R1/ T/311.2-336.8 m, OL-KR3/T/242.6-253.2 m, OL-KR5/T/277.2-284.6 m, OL-KR11/ T/597.5-628.1 m and OL-KR12/T/363-368 m) or Na-Ca-Cl (OL-KR1/T/524.4- 528.4 m, OL-KR5/T/457.2-476.2 m and OL-KR9/T/468.2-482.2 m). The groundwater samples from OL-KR1/T/151.2-156.8 m, OL-KR3/T/242.6- 253.2 m, OL-KR3/T/242.6-253.2 m, OL-KR5/T/277.2-284.2 m, OL-KR11/T/597.5-628.1 m and OL-KR12/T/363-368 m were brackish (1000 mg/L < TDS < 10000 mg/L) according to Davis's (1964) TDS classification. Other samples (OL-KR1/T/524.4-528.4 m, OL-KR5/ T/457.2-476.2 m and OL-KR9/T/468.2-482.2 m), were saline (TDS> 10000 mg/L). Comparison of analytical results of the samples to earlier results shows that some changes were seen between samplings done at the different times. Only the groundwater sampled from OL-KR1/T/311.2-336.8 m had significant changes in its chemical composition during the reference period, but also in OL-KR1/T/524.4-528.4 m, OL-KR5/ T

Proposed solar neutrino experiment using 81Br(nu,e-)81Kr

International Nuclear Information System (INIS)

Hurst, G.S.; Chen, C.H.; Kramer, S.D.; Allman, S.L.

1984-12-01

It has now been shown that it is feasible to measure the 7 Be neutrino source in the sun by using the reaction 81 Br(nu,e - ) 81 Kr in a radiochemical experiment. Such an experiment would be quite similar to the Davis, Cleveland, and Rowley method for measuring the 8 B neutrino using 37 Cl(nu,e - ) 37 Ar except that the resonance ionization spectroscopy (RIS) method (instead of decay counting) would be employed to count the 2 x 10 5 -yr 81 Kr atoms

Production of Mg and Al Auger electrons by noble gas ion bombardment of Mg and Al surfaces. [3 KeV, electron promotion

Energy Technology Data Exchange (ETDEWEB)

Ferrante, J; Pepper, S V [National Aeronautics and Space Administration, Cleveland, Ohio (USA). Lewis Research Center

1976-08-01

In this letter the relative production efficiency of Mg and Al Auger electrons by He, Ne, Ar, Kr and Xe ion bombardment as a function of ion energy (<=3 keV) is reported. Some comments on the interpretation of the results in terms of electron promotion are also given.

MULTI-KEV X-Ray Yields From High-Z Gas Targets Fielded At Omega

International Nuclear Information System (INIS)

Kane, J.O.; Fournier, K.B.; May, M.J.; Colvin, J.D.; Thomas, C.A.; Marrs, R.E.; Compton, S.M.; Moody, J.D.; Bond, E.J.; Davis, J.F.

2010-01-01

The authors report on modeling of x-ray yield from gas-filled targets shot at the OMEGA laser facility. The OMEGA targets were 1.8 mm long, 1.95 mm in diameter Be cans filled with either a 50:50 Ar:Xe mixture, pure Ar, pure Kr or pure Xe at ∼ 1 atm. The OMEGA experiments heated the gas with 20 kJ of 3ω (∼ 350 nm) laser energy delivered in a 1 ns square pulse. the emitted x-ray flux was monitored with the x-ray diode based DANTE instruments in the sub-keV range. Two-dimensional x-ray images (for energies 3-5 keV) of the targets were recorded with gated x-ray detectors. The x-ray spectra were recorded with the HENWAY crystal spectrometer at OMEGA. Predictions are 2D r-z cylindrical with DCA NLTE atomic physics. Models generally: (1) underpredict the Xe L-shell yields; (2) overpredict the Ar K-shell yields; (3) correctly predict the Xe thermal yields; and (4) greatly underpredict the Ar thermal yields. However, there are spreads within the data, e.g. the DMX Ar K-shell yields are correctly predicted. The predicted thermal yields show strong angular dependence.

Effect of UV laser irradiation on tissue

International Nuclear Information System (INIS)

Nakayama, Takeyoshi; Kubo, Uichi

1992-01-01

Laser-tissue interactions have been investigated through Electron Probe Micro Analysis (EPMA), UV-visible optical absorption and Fourier Transform Infrared Spectroscopy (FTIR). Three excimer lasers, ArF, KrF and XeCl, were used to irradiate tissue; cow thighbone and gelatin thin film. Features of UV laser irradiation are described. (author)

Noble gas and halogen constraints on fluid sources in iron oxide-copper-gold mineralization: Mantoverde and La Candelaria, Northern Chile

Science.gov (United States)

Marschik, Robert; Kendrick, Mark A.

2015-03-01

The noble gas (Ar, Kr, Xe) and halogen (Cl, Br, I) composition of fluid inclusions in hydrothermal quartz and calcite related to the hypogene iron oxide-copper-gold (IOCG) mineralization at Mantoverde and Candelaria, Chile, have been investigated to provide new insights of fluid and salinity sources in Andean IOCG deposits. A combination of mechanical extraction by crushing and thermal decrepitation methods was applied and collectively indicate that fluid inclusions with salinities ranging from 3.4 up to 64 wt% NaCl equivalent have molar Br/Cl and I/Cl ratios of between 0.5 × 10-3 and 3.0 × 10-3 and I/Cl of between 8 × 10-6 and 25 × 10-6 in the majority of samples, with maximum values of 5.2 × 10-3 obtained for Br/Cl and 64 × 10-6 for I/Cl in fluid inclusions within individual samples. The fluid inclusions have age-corrected 40Ar/36Ar ratios ranging from the atmospheric value of 296 up to 490 ± 45, indicating the presence of crustal- or mantle-derived excess 40Ar in the fluid inclusions of most samples. The fluid inclusions have 84Kr/36Ar and 130Xe/36Ar ratios intermediate of air and air-saturated water. However, 40Ar/36Ar is not correlated with either 84Kr/36Ar or 130Xe/36Ar, and the fluid inclusion 36Ar concentrations of 0.2-3.5 × 10-10 mol/g (calculated from measured Cl/36Ar and thermometric salinity measurements) extend below the seawater value of 0.34 × 10-10 mol/g, suggesting that contamination with modern air is a minor artifact. The range of fluid inclusion Br/Cl and I/Cl ratios overlap those previously documented for the mantle and magmatic-hydrothermal ore deposits, and the fluids' unusually low 36Ar concentration is consistent with the involvement of magmatic-hydrothermal fluids. Input of additional non-magmatic fluid components is suggested by the spread in Br/Cl and I/Cl to values characteristic of bittern brine sedimentary formation waters and near atmospheric 40Ar/36Ar. These data are compatible with mixing of magmatic-hydrothermal fluids

124Xe(n,γ)125Xe and 124Xe(n,2n)123Xe measurements for National Ignition Facility

Science.gov (United States)

Bhike, Megha; Ludin, Nurin; Tornow, Werner

2015-05-01

The cross section for the 124Xe(n,γ)125Xe reaction has been measured for the first time for neutron energies above 100 keV. In addition, the 124Xe(n,2n)123Xe reaction has been studied between threshold and 14.8 MeV. The results of these measurements provide sensitive diagnostic tools for investigating properties of the inertial confinement fusion plasma in Deuterium-Tritium (DT) capsules at the National Ignition Facility (NIF) located at Lawrence Livermore National Laboratory.

124Xe(n,γ125Xe and 124Xe(n,2n123Xe measurements for National Ignition Facility

Directory of Open Access Journals (Sweden)

Bhike Megha

2015-01-01

Full Text Available The cross section for the 124Xe(n,γ125Xe reaction has been measured for the first time for neutron energies above 100 keV. In addition, the 124Xe(n,2n123Xe reaction has been studied between threshold and 14.8 MeV. The results of these measurements provide sensitive diagnostic tools for investigating properties of the inertial confinement fusion plasma in Deuterium-Tritium (DT capsules at the National Ignition Facility (NIF located at Lawrence Livermore National Laboratory.

A novel method for producing multiple ionization of noble gas

International Nuclear Information System (INIS)

Wang Li; Li Haiyang; Dai Dongxu; Bai Jiling; Lu Richang

1997-01-01

We introduce a novel method for producing multiple ionization of He, Ne, Ar, Kr and Xe. A nanosecond pulsed electron beam with large number density, which could be energy-controlled, was produced by incidence a focused 308 nm laser beam onto a stainless steel grid. On Time-of-Flight Mass Spectrometer, using this electron beam, we obtained multiple ionization of noble gas He, Ne, Ar and Xe. Time of fight mass spectra of these ions were given out. These ions were supposed to be produced by step by step ionization of the gas atoms by electron beam impact. This method may be used as a ideal soft ionizing point ion source in Time of Flight Mass Spectrometer

Xe isotopic constraints on cycling of deep Earth volatiles

Science.gov (United States)

Parai, R.; Mukhopadhyay, S.

2017-12-01

The modern deep Earth volatile budget reflects primordial volatiles delivered during accretion, radiogenic ingrowth of volatile species (e.g., 40Ar produced by 40K decay), outgassing in association with mantle processing, and regassing via subduction. The noble gases are unique volatile tracers in that they are chemically inert, but are thought to be trapped within hydrous alteration phases in downwelling lithologies. Noble gases thus provide a tracer of volatile transport between the deep Earth and surface reservoirs. Constraints on the fluxes of noble gases between deep Earth and surface reservoirs over time can accordingly be used to provide insight into temperature conditions at subduction zones, limits on volatile cycling, and the evolving distribution of major volatile species in terrestrial reservoirs over time. Xe isotope systematics in mantle-derived rocks show that 80-90% of the mantle Xe budget is derived from recycling of atmospheric Xe, indicating that atmospheric Xe is retained in subducting slabs beyond depths of magma generation in subduction zones over Earth history. We present an integrated model of Xe cycling between the mantle and atmosphere in association with mantle processing over Earth history. We test a wide variety of outgassing and regassing rates and take the evolution of the atmospheric Xe isotopic composition [e.g., 1] into account. Models in which the deep Earth transitions from a net outgassing to net regassing regime best satisfy Xe isotopic constraints from mantle-derived rocks [2-6]. [1] Avice et al., 2017; Nature Communications, 8; [2] Mukhopadhyay, 2012, Nature 486, 101-104; [3] Parai et al., 2012, EPSL 359-360, 227-239; [4] Parai and Mukhopadhay, 2015, G-cubed 16, 719-735; [5] Peto et al., 2013, EPSL 369-370, 13-23; [6] Tucker et al., 2012, EPSL 355-356, 244-254.

New experimental stopping power data of 4He, 16O, 40Ar, 48Ca and 84Kr projectiles in different solid materials

Science.gov (United States)

Trzaska, W. H.; Knyazheva, G. N.; Perkowski, J.; Andrzejewski, J.; Khlebnikov, S. V.; Kozulin, E. M.; Malkiewicz, T.; Mutterer, M.; Savelieva, E. O.

2018-03-01

New experimental data on energy loss of 4He, 16O, 40Ar, 48Ca and 84Kr ions in thin, self-supporting foils of C, Al, Ni, Ag, Lu, Au, Pb and Th are presented. The measurements, using the TOF-E method, were done in a very broad energy range around the stopping power maximum; typically from 0.1 to 11 MeV/u. When available, the extracted stopping power values are compared with the previously published data. The overall agreement is good although a fair comparison is difficult as the covered energy range is much larger than in previous measurements. The small error bars and a broad coverage allowed us to test the predictions of theoretical codes: PASS, CasP, and semi-empirical programs: SRIM, LET, MSTAR, and the Hubert table predictions. The deviations of PASS predictions from the experimental data do not exceed 20% for all the measured combinations. CasP predictions are within 15% from the data for heavier ions but diverge up to 40% for lighter ions. Semi-empirical approaches, including SRIM, deviate from the experimental data by less than 5% for the regions already covered by previous experiments but err by about 10-20% for the ion/target combinations that were not measured before: Ca in Lu as well as Kr in Lu, Pb, and Th.

Geophysical drillhole logging of the drillholes OL-KR40, OL-KR41, OL-KR41B, OL-KR42, OLKR42B, OL-KR43 and OL-KR43B, at Olkiluoto 2006 and 2007

International Nuclear Information System (INIS)

Tarvainen, A.-M.

2007-05-01

Suomen Malmi Oy conducted geophysical borehole logging of the boreholes drillholes OL-KR40, OL-KR41, OL-KR41B, OL-KR42, OL-KR42B, OL-KR43 and OL-KR43B at the Olkiluoto site in Eurajoki during August, September, December 2006 and January 2007. The survey is a part of Posiva Oy's detailed investigation program for the final disposal of spent nuclear fuel. The assignment included the field work and processing of the acoustic data. The report describes field operation, equipment as well as processing procedures and shows the obtained results and an analysis of their quality in the appendices. The raw and processed data are delivered digitally in WellCAD, PDF and Excel format. (orig.)

Van der Waals bond in dimers: H2Ne, H2Ar, H2Kr

International Nuclear Information System (INIS)

Waaijer, M.

1981-01-01

The H 2 -inert gas dimers H 2 X, and particularly H 2 Ne, H 2 Ar and H 2 Kr, form the subject of this thesis and are loosely bound van der Waals complexes, which is reflected in the low number of bound states and the small anisotropic interaction. The H 2 X dimers studied are formed in a supersonic nozzle expansion, in which the internal energy is converted into the macroscopic flow energy, establishing an internal temperature drop to 3 K, which favours dimer formation. Because of this cooling the H 2 X dimers relax to the lowest rotational states. The hyperfine transitions have been measured using magnetic beam resonance and yield information about the isotropic as well as the anisotropic intermolecular potential in the range between the classical turning points and in the adjacent part of the repulsive branch. The sensitivity of the method is very high and slight changes in the intermolecular potential cause significant effects. The analysis of the measured hyperfine transitions incorporates all interacting states of the molecule, bound as well as unbound (continuum) states. For H 2 Ne, which is the best studied H 2 -inert gas system from the experimental point of view, the author succeeded in establishing an intermolecular potential, that provides a solid ground for comparison with future ab initio calculations. (Auth.)

Long-range interactions of excited He atoms with ground-state noble-gas atoms

KAUST Repository

Zhang, J.-Y.; Qian, Ying; Schwingenschlö gl, Udo; Yan, Z.-C.

2013-01-01

The dispersion coefficients C6, C8, and C10 for long-range interactions of He(n1,3S) and He(n1,3P), 2≤n≤10, with the ground-state noble-gas atoms Ne, Ar, Kr, and Xe are calculated by summing over the reduced matrix elements of multipole transition

EPR investigation of electronic excitations in rare gas solids (Review Article)

Science.gov (United States)

Zhitnikov, R. A.; Dmitriev, Yu. A.

1998-10-01

The methods are described for producing unstable paramagnetic excited states in rare gas cryocrystals Ne, Ar, Kr, and Xe through the trapping, in the cryocrystals growing from the gas phase, the products of the gas discharge taking place in the same or other rare gas. The paper presents a technique and results of an observation and investigation of excited states in rare gas cryocrystals with electron paramagnetic resonance (EPR). The discovered unstable paramagnetic centers are interpreted as being local metastable excited np5(n+1)s atomic-type states in rare gas cryocrystals which are subject to the action of the anisotropic electric field resulted from the crystal surroundings distorted by the center. An account is given of the mechanisms for formation of observed paramagnetic excited states in cryocrystals which arise owing to the excitation energy of the metastable 3P2 atoms of Ne, Ar, Kr, Xe and He 23S1 and 21S0 atoms that form in the discharge in an appropriate gas and trap in the growing cryocrystal.

Migration of noble gas atoms in interaction with vacancies in silicon

International Nuclear Information System (INIS)

Pizzagalli, L; Charaf-Eddin, A

2015-01-01

First principles calculations in combination with the nudged elastic band method have been performed in order to determine the mobility properties of various noble gas species (He, Ne, Ar, Kr, and Xe) in silicon, a model semiconducting material. We focussed on single impurity, in interstitial configuration or forming a complex with a mono- or a di-vacancy, since the latter are known to be present and to play a key role in the formation of extended defects like bubbles or platelets. We determined several migration mechanisms and associated activation energies and have discussed these results in relation to available experiments. In particular, conflicting measured values of the migration energy of helium are explained by the present calculations. We also predict that helium diffuses solely as an interstitial, while an opposite behaviour is found for heavier species such as Ar, Kr, and Xe, with the prevailing role of complexes in that case. Finally, our calculations indicate that extended defects evolution by Ostwald ripening is possible for helium and maybe neon, but is rather unlikely for heavier noble gas species. (paper)

Microstructures, mineral chemistry, noble gases and nitrogen in the recent fall, Bhuka iron (IAB) meteorite

Science.gov (United States)

Murty, S. V. S.; Ranjith, P. M.; Ray, Dwijesh; Ghosh, S.; Chattopadhyay, Basab; Shrivastava, K. L.

2016-10-01

We report some chemical, petrological and isotopic studies of the Bhuka iron meteorite that fell in Rajasthan, India in 2005. Numerous silicate and graphite inclusions are visible on the surface of the hand specimen. In the polished and etched surface studied, irregular patches of graphite are found as the most dominant inclusion and commonly associated with pure corundum (95 wt% Al2O3), spinel, feldspar and Si-rich phases. Apart from typical lamellar intergrowth with kamacite (i.e. the Widmänstatten pattern), taenites are also commonly found to occur as a rim of the graphite inclusions. P-rich (up to 10 wt%) taenites are also found locally within the recrystallised kamacite matrix. Based on mineralogy, texture and bulk composition, Bhuka resembles the low-Ni IAB subgroup (ungrouped). Noble gas isotope studies suggest He, Ne and Ar are mostly of cosmogenic origin, while Kr and Xe are a mixture of cosmogenic, radiogenic and trapped components. A pre-atmospheric radius of 10±1 cm and a cosmic ray exposure age of 346±52 Ma are derived based on depth dependant (3He/4He)c and 38Arc respectively, as per the production systematics of cosmogenic noble gas isotopes (Ammon et al., 2009). Cosmogenic 83Kr and 126Xe yield production rates of 12 and 0.335 (in 10-15ccSTP/g Ma) for 83Kr and 126Xe respectively. Presence of trapped Kr and Xe, with (84Kr/132Xe)t=2 and radiogenic 129Xe=120×10-12 ccSTP/g are due to presence of graphite/silicate inclusions in the analysed sample. Over 150% excess 131Xec than expected from spallation suggests contribution from (n,ɤ) reactions from Ba from inclusions and suggests irradiation of pre-atmospheric object in a larger body, indicative of complex irradiation. Trapped N of 24 ppm, with δ15N=-10.7±0.8‰ observed in Bhuka, is heavier than the range observed hither to in IAB irons.

Milestone Report - M4FT-15OR03120218 - A Literature Search on the Effects of the Decay of ⁸⁵Kr to ⁸⁵Rb on Long-term Storage Options

Energy Technology Data Exchange (ETDEWEB)

Bruffey, Stephanie H [ORNL; Jubin, Robert Thomas [ORNL; Spencer, Barry B [ORNL

2015-10-01

Reprocessing of UNF that has been out of the reactor for less than about 50 y requires the removal of ⁸⁵Kr from the process off-gas streams. This is needed despite the relatively small amount of that isotope in the combined Xe and Kr inventory (Table 1). The decay of ⁸⁵Kr to ⁸⁵Rb presents challenges to the materials that will potentially be used to remove and store the Kr recovered from the off-gas. To address some of these problems, a thorough literature survey was completed, and the results of that analysis are summarized in this document.

Flow measurements in biological systems using Xe-127 and Xe-133

International Nuclear Information System (INIS)

Tripathi, R.R.

1981-01-01

Xe-133 and Xe-127 are widely used for quantitative evaluation of ventilation in human subjects. Owing to differences in scattering in the biological system as well as differences in the detector response to photons of selected energies, clinical Xe-133 images are much more distorted than the corresponding Xe-127 images. This thesis concerns itself with the evaluation of Xe-133 and Xe-127 as potential tracers for pulmonary function studies. Through the simulation of clinical images it is shown that such smaller abnormalities are able to be detected with Xe-127 than with Xe-133. It is also found that even for poorly ventilated regions, the measured lesion size in the simulated image is comparable to the known lesion size when studied with Xe-127. With Xe-133, however, the measured size of the lesion is smaller than its known size. By fitting the washout portion of the clinical data to a linear sum of two exponentials, a weighted average clearance constant for the tracer - which relates to the reciprocal of the mean flow through the system - can be calculated and used as an index for comparison of the two Xenon isotopes. When an appropriate model is used for data interpretation, more accurate clinical information can be derived from the Xe-127 data. Unlike Xe-133, ventilation study with Xe-127 can be performed immediately after the perfusion study with Tc-99m. Lower radiation dose and longer shelf-life of Xe-127 are added advantages over Xe-133. Various compartmental and non-compartmental models are examined and appropriate technique(s) for clinical data interpretation is(are) recommended

Feasibility of a 81Br(ν,e-) 81Kr solar neutrino experiment

International Nuclear Information System (INIS)

Hurst, G.S.; Chen, C.H.; Kramer, S.D.; Cleveland, B.T.; Davis, R. Jr.; Rowley, R.K.; Gabbard, F.; Schima, F.J.

1984-01-01

A solar neutrino experiment utilizing the interaction of 81 Br(ν,e - ) 81 Kr to study the 7 Be neutrino source in the interior of the sun is shown to be feasible. Resonance ionization spectroscopy was used to count less than 1000 atoms of 2 x 10 5 -yr 81 Kr, making the bromine experiment possible. Except for the method of counting product atoms, the bromine experiment would be very similar to the successful chlorine detector 37 Cl(ν,e - ) 37 Ar, and thus it is a natural sequel to the only solar neutrino experiment to date

Recombination of KrD+ and KrH+ ions in afterglow plasma

International Nuclear Information System (INIS)

Korolov, I; Kotrik, T; Plasil, R; Hejduk, M; Varju, J; Dohnal, P; Glosik, J

2009-01-01

Reported is flowing afterglow (FALP) study of recombination of KrH + and KrD + ions with electrons at 250 K in mixtures of He/Kr/H 2 and He/Kr/D 2 , respectively. The influence of fast recombining cluster ions formation on apparent effective recombination rate coefficients (α eff ) was measured and used in data analysis. The obtained binary rate coefficients for recombination of KrH + and KrD + are α KrH+ = 2x10 -8 cm 3 s -1 and α KrD+ = 1x10 -8 cm 3 s -1 .

Recombination of KrD+ and KrH+ ions in afterglow plasma

Science.gov (United States)

Korolov, I.; Kotrik, T.; Plasil, R.; Hejduk, M.; Varju, J.; Dohnal, P.; Glosik, J.

2009-11-01

Reported is flowing afterglow (FALP) study of recombination of KrH+ and KrD+ ions with electrons at 250 K in mixtures of He/Kr/H2 and He/Kr/D2, respectively. The influence of fast recombining cluster ions formation on apparent effective recombination rate coefficients (αeff) was measured and used in data analysis. The obtained binary rate coefficients for recombination of KrH+ and KrD+ are αKrH+ = 2×10-8 cm3s-1 and αKrD+ = 1×10-8 cm3s-1.

Measurement of fission gases released by HTR irradiation samples in the BR 2 reactor (Mol/Belgium)

International Nuclear Information System (INIS)

Koetter, H.; Mueller, H.B.

1975-04-01

During the irradiation of HTR-test fuel (coated particles resp. compacts) the release rate of fission gases is measured automatically. For that purpose the γ-spectrum of the sweep gas is analyzed with respect to the isotopes Xe-133, Xe-135, Xe-135sup(m), Xe-137, Xe-138, Kr-85sup(m), Kr-87, Kr-88, Kr-89. Gas sampling, spectral analysis, data handling and evaluation are controlled by computer. (orig.) [de

Absolute Kr I and Kr II transition probabilities

International Nuclear Information System (INIS)

Brandt, T.; Helbig, V.; Nick, K.P.

1982-01-01

Transition probabilities for 11 KrI and 9 KrII lines between 366.5 and 599.3nm were obtained from measurements with a wall-stabilised arc at atmospheric pressure in pure krypton. The population densities of the excited krypton levels were calculated under the assumption of LTE from electron densities measured by laser interferometry. The uncertainties for the KrI and the KrII data are 15 and 25% respectively. (author)

Noble gases, nitrogen, cosmic ray exposure history and mineralogy of Beni M'hira (L6) chondrite

Science.gov (United States)

Mahajan, Ramakant R.; Nejia, Laridhi Ouazaa; Ray, Dwijesh; Naik, Sekhar

2018-03-01

The concentrations and isotopic composition of noble gases helium (He), neon (Ne), argon (Ar), krypton (Kr), xenon(Xe) and nitrogen were measured in the Beni M'hira L6 chondrite. The cosmic ray exposure age of Beni M'hira is estimated of 15.6 ± 3.7 (Ma). The radiogenic age, of around 485 ± 64 Ma, derived from 4He, and of around 504 ± 51 Ma from 40Ar, suggests an age resetting indicating the event impact. The heavy noble gases (Ar, Kr and Xe) concentrations imply that the gas is a mixture of trapped component Q and solar wind. The measured nitrogen abundance of 0.74 ppm and the isotopic signature of δ15N = 14.6‰ are within the range of ordinary chondrites. The homogeneous chemical composition of olivine (Fa:26 ± 0.25) and low-Ca pyroxene (Fs:22.4 ± 0.29) suggest that the Beni M'hira meteorite is an equilibrated chondrite. This is further corroborated by strong chondrule-matrix textural integration (lack of chondrules, except a few relict clast). Shock metamorphism generally corresponds to S5 (>45 GPa), however, locally disequilibrium melting (shock-melt veins) suggests, that the peak shock metamorphism was at ∼75 GPa, 950 °C.

Stopping power for heavy ions in gases: a comparative study

International Nuclear Information System (INIS)

Diwan, P.K.; Singh, Lakhwant; Singh, Gurinder; Shyam Kumar

1999-01-01

The accurate knowledge of stopping power for heavy ions in gases is of paramount importance in nuclear reaction studies for the identification of reaction products involving ΔE-E telescope detectors. In the present work, it has been calculated the stopping power values for different heavy ions, such as Ne, Ar, Cu, Kr and Ag in various gas absorbers like H 2 , He, N 2 , Ne, Ar, Kr and Xe in the energy domain ∼ 2.5-6 MeV/n using the SRIM-98 code recently developed by Ziegler and the formulations of Benton and Henke, Hubert et al, Mukherjee and Nayak and Northcliffe and Schilling. This study has been undertaken in order to establish the validity of various semiempirical formulations for gas targets

Effect of low-xenon and krypton supplementation on signal/noise of regional CT-based ventilation measurements.

Science.gov (United States)

Chon, Deokiee; Beck, Kenneth C; Simon, Brett A; Shikata, Hidenori; Saba, Osama I; Hoffman, Eric A

2007-04-01

Xenon computed tomography (Xe-CT) is used to estimate regional ventilation by measuring regional attenuation changes over multiple breaths while rebreathing a constant Xe concentration ([Xe]). Xe-CT has potential human applications, although anesthetic properties limit [Xe] to krypton (Kr) combination, on time constant (TC) determination. Six anesthetized sheep were scanned prone and supine using multidetector row CT. Lungs were imaged by respiratory gating during washin of a 30%, 40%, 55% Xe, and a 30% Xe/30% Kr mixture. Using Kr avoids unwanted effects of Xe. Mean TCs, coefficients of variation (CV), and half confidence intervals (CI)/mean served as indexes of sensitivity to noise. Mean supine and prone TCs of three [Xe] values were not significantly different. Average CVs of TCs increased from 57% (55% Xe), 58% (40% Xe), and 73% (30% Xe) (P < 0.05: paired t-tests; 30% Xe vs. higher [Xe]). Monte Carlo simulation indicated a CV based on inherent image noise was 8% for 55% Xe and 17% for 30% Xe (P < 0.05). Adding 30% Kr to 30% Xe gave a washin signal equivalent to 40% Xe. Half CI/mean using the 30% Xe/30% Kr mixture was not significantly different from 55 and 40% Xe. Although average TCs were not affected by changes in [Xe], the higher CV and half CI/mean suggested reduced signal-to-noise ratio at the 30% [Xe]. The 30% Xe/30% Kr mixture was comparable to that of 40% Xe, providing an important agent for CT-based assessment of regional ventilation in humans.

Noble Gases as tracers of fluid migration in the Haynesville shale and overlying strata

Science.gov (United States)

Byrne, D. J.; Barry, P. H.; Lawson, M.; Ballentine, C. J.

2017-12-01

Noble gases are ideal tracers of physical processes and fluid provenance in crustal systems. Due to their inert nature, they are unaffected by chemical alteration, redox, or biological phenomena that fractionate other geochemical tracers. Noble gas analysis has been used to quantify fluid provenance, interactions, and ages in petroleum systems [1,2], but the effects of hydrocarbon migration on noble gas signatures have not been directly observed. The Haynesville Shale (East Texas & Louisiana), is exploited commercially for unconventional shale gas, but also acts as the source-rock for overlying conventional reservoirs. We present noble gas isotope and abundance data in samples collected from 9 natural gas wells sourced from the Haynesville Shale, as well as 21 from reservoirs in the overlying Cotton Valley (n=7), Travis Peak (n=9), and James (n=5) groups. Using a stratigraphic model, we observe systematic changes in the noble gas signatures as the fluids migrate from the Haynesville source rock to the overlying conventional accumulations. Helium isotope ratios (3He/4He) are strongly radiogenic in the Haynesville and stratigraphically older conventional reservoirs, with the younger reservoirs showing evidence of a mantle helium input. Argon isotope ratios (40Ar/36Ar) are strongly correlated with high 3He/4He, suggesting a similar provenance for radiogenic 40Ar and mantle 3He. Concentrations of groundwater-derived 36Ar are consistently higher in the conventional reservoirs than in the Haynesville shale, reflecting the greater interaction with groundwater during migration. However, 20Ne/36Ar ratios are not significantly different, suggesting that solubility-dependent partitioning is not simply dependent on vertical or horizontal migration distance. Krypton and xenon abundances are higher than expected for groundwater in all samples, a phenomenon that has been observed in many other hydrocarbon accumulations [3]. The excess Xe/Kr ratio is highest in the Haynesville

Photoionization dynamics of excited Ne, Ar, Kr and Xe atoms near threshold

International Nuclear Information System (INIS)

Sukhorukov, V L; Petrov, I D; Schäfer, M; Merkt, F; Ruf, M-W; Hotop, H

2012-01-01

A review of experimental and theoretical studies of the threshold photoionization of the heavier rare-gas atoms is presented, with particular emphasis on the autoionization resonances in the spectral region between the lowest two ionization thresholds 2 P 3/2 and 2 P 1/2 , accessed from the ground or excited states. Observed trends in the positions, widths and shapes of the autoionization resonances depending on the atomic number, the principal quantum number n, the orbital angular momentum quantum number ℓ and further quantum numbers specifying the fine- and hyperfine-structure levels are summarized and discussed in the light of ab initio and multichannel quantum defect theory calculations. The dependence of the photoionization spectra on the initially prepared neutral state are also discussed, including results on the photoionization cross sections and photoelectron angular distributions of polarized excited states. The effects of various approximations in the theoretical treatment of photoionization in these systems are analysed. The very large diversity of observed phenomena and the numerous anomalies in spectral structures associated with the threshold ionization of the rare-gas atoms can be described in terms of a limited set of interactions and dynamical processes. Examples are provided illustrating characteristic aspects of the photoionization, and sets of recommended parameters describing the energy-level structure and photoionization dynamics of the rare-gas atoms are presented which were extracted in a critical analysis of the very large body of experimental and theoretical data available on these systems in the literature. (topical review)

Anisotropic flow in Xe-Xe collisions at 5.44 TeV

CERN Document Server

Acharya, Shreyasi; The ALICE collaboration; Adamova, Dagmar; Adolfsson, Jonatan; Aggarwal, Madan Mohan; Aglieri Rinella, Gianluca; Agnello, Michelangelo; Agrawal, Neelima; Ahammed, Zubayer; Ahn, Sang Un; Aiola, Salvatore; Akindinov, Alexander; Al-turany, Mohammad; Alam, Sk Noor; Silva De Albuquerque, Danilo; Aleksandrov, Dmitry; Alessandro, Bruno; Alfaro Molina, Jose Ruben; Ali, Yasir; Alici, Andrea; Alkin, Anton; Alme, Johan; Alt, Torsten; Altenkamper, Lucas; Altsybeev, Igor; Anaam, Mustafa Naji; Andrei, Cristian; Andreou, Dimitra; Andrews, Harry Arthur; Andronic, Anton; Angeletti, Massimo; Anguelov, Venelin; Anson, Christopher Daniel; Anticic, Tome; Antinori, Federico; Antonioli, Pietro; Anwar, Rafay; Apadula, Nicole; Aphecetche, Laurent Bernard; Appelshaeuser, Harald; Arcelli, Silvia; Arnaldi, Roberta; Arnold, Oliver Werner; Arsene, Ionut Cristian; Arslandok, Mesut; Audurier, Benjamin; Augustinus, Andre; Averbeck, Ralf Peter; Azmi, Mohd Danish; Badala, Angela; Baek, Yong Wook; Bagnasco, Stefano; Bailhache, Raphaelle Marie; Bala, Renu; Baldisseri, Alberto; Ball, Markus; Baral, Rama Chandra; Barbano, Anastasia Maria; Barbera, Roberto; Barile, Francesco; Barioglio, Luca; Barnafoldi, Gergely Gabor; Barnby, Lee Stuart; Ramillien Barret, Valerie; Bartalini, Paolo; Barth, Klaus; Bartsch, Esther; Bastid, Nicole; Basu, Sumit; Batigne, Guillaume; Batyunya, Boris; Batzing, Paul Christoph; Bazo Alba, Jose Luis; Bearden, Ian Gardner; Beck, Hans; Bedda, Cristina; Behera, Nirbhay Kumar; Belikov, Iouri; Bellini, Francesca; Bello Martinez, Hector; Bellwied, Rene; Espinoza Beltran, Lucina Gabriela; Belyaev, Vladimir; Bencedi, Gyula; Beole, Stefania; Bercuci, Alexandru; Berdnikov, Yaroslav; Berenyi, Daniel; Bertens, Redmer Alexander; Berzano, Dario; Betev, Latchezar; Bhaduri, Partha Pratim; Bhasin, Anju; Bhat, Inayat Rasool; Bhatt, Himani; Bhattacharjee, Buddhadeb; Bhom, Jihyun; Bianchi, Antonio; Bianchi, Livio; Bianchi, Nicola; Bielcik, Jaroslav; Bielcikova, Jana; Bilandzic, Ante; Biro, Gabor; Biswas, Rathijit; Biswas, Saikat; Blair, Justin Thomas; Blau, Dmitry; Blume, Christoph; Boca, Gianluigi; Bock, Friederike; Bogdanov, Alexey; Boldizsar, Laszlo; Bombara, Marek; Bonomi, Germano; Bonora, Matthias; Borel, Herve; Borissov, Alexander; Borri, Marcello; Botta, Elena; Bourjau, Christian; Bratrud, Lars; Braun-munzinger, Peter; Bregant, Marco; Broker, Theo Alexander; Broz, Michal; Brucken, Erik Jens; Bruna, Elena; Bruno, Giuseppe Eugenio; Budnikov, Dmitry; Buesching, Henner; Bufalino, Stefania; Buhler, Paul; Buncic, Predrag; Busch, Oliver; Buthelezi, Edith Zinhle; Bashir Butt, Jamila; Buxton, Jesse Thomas; Cabala, Jan; Caffarri, Davide; Caines, Helen Louise; Caliva, Alberto; Calvo Villar, Ernesto; Soto Camacho, Rabi; Camerini, Paolo; Capon, Aaron Allan; Carena, Francesco; Carena, Wisla; Carnesecchi, Francesca; Castillo Castellanos, Javier Ernesto; Castro, Andrew John; Casula, Ester Anna Rita; Ceballos Sanchez, Cesar; Chandra, Sinjini; Chang, Beomsu; Chang, Wan; Chapeland, Sylvain; Chartier, Marielle; Chattopadhyay, Subhasis; Chattopadhyay, Sukalyan; Chauvin, Alex; Cheshkov, Cvetan Valeriev; Cheynis, Brigitte; Chibante Barroso, Vasco Miguel; Dobrigkeit Chinellato, David; Cho, Soyeon; Chochula, Peter; Chowdhury, Tasnuva; Christakoglou, Panagiotis; Christensen, Christian Holm; Christiansen, Peter; Chujo, Tatsuya; Chung, Suh-urk; Cicalo, Corrado; Cifarelli, Luisa; Cindolo, Federico; Cleymans, Jean Willy Andre; Colamaria, Fabio Filippo; Colella, Domenico; Collu, Alberto; Colocci, Manuel; Concas, Matteo; Conesa Balbastre, Gustavo; Conesa Del Valle, Zaida; Contreras Nuno, Jesus Guillermo; Cormier, Thomas Michael; Corrales Morales, Yasser; Cortese, Pietro; Cosentino, Mauro Rogerio; Costa, Filippo; Costanza, Susanna; Crkovska, Jana; Crochet, Philippe; Cuautle Flores, Eleazar; Cunqueiro Mendez, Leticia; Dahms, Torsten; Dainese, Andrea; Dani, Sanskruti; Danisch, Meike Charlotte; Danu, Andrea; Das, Debasish; Das, Indranil; Das, Supriya; Dash, Ajay Kumar; Dash, Sadhana; De, Sudipan; De Caro, Annalisa; De Cataldo, Giacinto; De Conti, Camila; De Cuveland, Jan; De Falco, Alessandro; De Gruttola, Daniele; De Marco, Nora; De Pasquale, Salvatore; Derradi De Souza, Rafael; Franz Degenhardt, Hermann; Deisting, Alexander; Deloff, Andrzej; Delsanto, Silvia; Deplano, Caterina; Dhankher, Preeti; Di Bari, Domenico; Di Mauro, Antonio; Di Ruzza, Benedetto; Arteche Diaz, Raul; Dietel, Thomas; Dillenseger, Pascal; Ding, Yanchun; Divia, Roberto; Djuvsland, Oeystein; Dobrin, Alexandru Florin; Domenicis Gimenez, Diogenes; Donigus, Benjamin; Dordic, Olja; Van Doremalen, Lennart Vincent; Dubey, Anand Kumar; Dubla, Andrea; Ducroux, Laurent; Dudi, Sandeep; Duggal, Ashpreet Kaur; Dukhishyam, Mallick; Dupieux, Pascal; Ehlers Iii, Raymond James; Elia, Domenico; Endress, Eric; Engel, Heiko; Epple, Eliane; Erazmus, Barbara Ewa; Erhardt, Filip; Ersdal, Magnus Rentsch; Espagnon, Bruno; Eulisse, Giulio; Eum, Jongsik; Evans, David; Evdokimov, Sergey; Fabbietti, Laura; Faggin, Mattia; Faivre, Julien; Fantoni, Alessandra; Fasel, Markus; Feldkamp, Linus; Feliciello, Alessandro; Feofilov, Grigorii; Fernandez Tellez, Arturo; Ferretti, Alessandro; Festanti, Andrea; Feuillard, Victor Jose Gaston; Figiel, Jan; Araujo Silva Figueredo, Marcel; Filchagin, Sergey; Finogeev, Dmitry; Fionda, Fiorella; Fiorenza, Gabriele; Flor, Fernando; Floris, Michele; Foertsch, Siegfried Valentin; Foka, Panagiota; Fokin, Sergey; Fragiacomo, Enrico; Francescon, Andrea; Francisco, Audrey; Frankenfeld, Ulrich Michael; Fronze, Gabriele Gaetano; Fuchs, Ulrich; Furget, Christophe; Furs, Artur; Fusco Girard, Mario; Gaardhoeje, Jens Joergen; Gagliardi, Martino; Gago Medina, Alberto Martin; Gajdosova, Katarina; Gallio, Mauro; Duarte Galvan, Carlos; Ganoti, Paraskevi; Garabatos Cuadrado, Jose; Garcia-solis, Edmundo Javier; Garg, Kunal; Gargiulo, Corrado; Gasik, Piotr Jan; Gauger, Erin Frances; De Leone Gay, Maria Beatriz; Germain, Marie; Ghosh, Jhuma; Ghosh, Premomoy; Ghosh, Sanjay Kumar; Gianotti, Paola; Giubellino, Paolo; Giubilato, Piero; Glassel, Peter; Gomez Coral, Diego Mauricio; Gomez Ramirez, Andres; Gonzalez, Victor; Gonzalez Zamora, Pedro; Gorbunov, Sergey; Gorlich, Lidia Maria; Gotovac, Sven; Grabski, Varlen; Graczykowski, Lukasz Kamil; Graham, Katie Leanne; Greiner, Leo Clifford; Grelli, Alessandro; Grigoras, Costin; Grigoryev, Vladislav; Grigoryan, Ara; Grigoryan, Smbat; Gronefeld, Julius Maximilian; Grosa, Fabrizio; Grosse-oetringhaus, Jan Fiete; Grosso, Raffaele; Guernane, Rachid; Guerzoni, Barbara; Guittiere, Manuel; Gulbrandsen, Kristjan Herlache; Gunji, Taku; Gupta, Anik; Gupta, Ramni; Bautista Guzman, Irais; Haake, Rudiger; Habib, Michael Karim; Hadjidakis, Cynthia Marie; Hamagaki, Hideki; Hamar, Gergoe; Hamid, Mohammed; Hamon, Julien Charles; Hannigan, Ryan; Haque, Md Rihan; Harris, John William; Harton, Austin Vincent; Hassan, Hadi; Hatzifotiadou, Despina; Hayashi, Shinichi; Heckel, Stefan Thomas; Hellbar, Ernst; Helstrup, Haavard; Herghelegiu, Andrei Ionut; Gonzalez Hernandez, Emma; Herrera Corral, Gerardo Antonio; Herrmann, Florian; Hetland, Kristin Fanebust; Hilden, Timo Eero; Hillemanns, Hartmut; Hills, Christopher; Hippolyte, Boris; Hohlweger, Bernhard; Horak, David; Hornung, Sebastian; Hosokawa, Ritsuya; Hota, Jyotishree; Hristov, Peter Zahariev; Huang, Chun-lu; Hughes, Charles; Huhn, Patrick; Humanic, Thomas; Hushnud, Hushnud; Hussain, Nur; Hussain, Tahir; Hutter, Dirk; Hwang, Dae Sung; Iddon, James Philip; Iga Buitron, Sergio Arturo; Ilkaev, Radiy; Inaba, Motoi; Ippolitov, Mikhail; Islam, Md Samsul; Ivanov, Marian; Ivanov, Vladimir; Izucheev, Vladimir; Jacak, Barbara; Jacazio, Nicolo; Jacobs, Peter Martin; Jadhav, Manoj Bhanudas; Jadlovska, Slavka; Jadlovsky, Jan; Jaelani, Syaefudin; Jahnke, Cristiane; Jakubowska, Monika Joanna; Janik, Malgorzata Anna; Jena, Chitrasen; Jercic, Marko; Jevons, Oliver; Jimenez Bustamante, Raul Tonatiuh; Jin, Muqing; Jones, Peter Graham; Jusko, Anton; Kalinak, Peter; Kalweit, Alexander Philipp; Kang, Ju Hwan; Kaplin, Vladimir; Kar, Somnath; Karasu Uysal, Ayben; Karavichev, Oleg; Karavicheva, Tatiana; Karczmarczyk, Przemyslaw; Karpechev, Evgeny; Kebschull, Udo Wolfgang; Keidel, Ralf; Keijdener, Darius Laurens; Keil, Markus; Ketzer, Bernhard Franz; Khabanova, Zhanna; Khan, Ahsan Mehmood; Khan, Shaista; Khan, Shuaib Ahmad; Khanzadeev, Alexei; Kharlov, Yury; Khatun, Anisa; Khuntia, Arvind; Kielbowicz, Miroslaw Marek; Kileng, Bjarte; Kim, Byungchul; Kim, Daehyeok; Kim, Dong Jo; Kim, Eun Joo; Kim, Hyeonjoong; Kim, Jinsook; Kim, Jiyoung; Kim, Minjung; Kim, Se Yong; Kim, Taejun; Kim, Taesoo; Kirsch, Stefan; Kisel, Ivan; Kiselev, Sergey; Kisiel, Adam Ryszard; Klay, Jennifer Lynn; Klein, Carsten; Klein, Jochen; Klein-boesing, Christian; Klewin, Sebastian; Kluge, Alexander; Knichel, Michael Linus; Knospe, Anders Garritt; Kobdaj, Chinorat; Varga-kofarago, Monika; Kohler, Markus Konrad; Kollegger, Thorsten; Kondratyeva, Natalia; Kondratyuk, Evgeny; Konevskikh, Artem; Konyushikhin, Maxim; Kovalenko, Oleksandr; Kovalenko, Vladimir; 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Paic, Guy; Palni, Prabhakar; Pan, Jinjin; Pandey, Ashutosh Kumar; Panebianco, Stefano; Papikyan, Vardanush; Pareek, Pooja; Park, Jonghan; Parkkila, Jasper Elias; Parmar, Sonia; Passfeld, Annika; Pathak, Surya Prakash; Patra, Rajendra Nath; Paul, Biswarup; Pei, Hua; Peitzmann, Thomas; Peng, Xinye; Pereira, Luis Gustavo; Pereira Da Costa, Hugo Denis Antonio; Peresunko, Dmitry Yurevich; Perez Lezama, Edgar; Peskov, Vladimir; Pestov, Yury; Petracek, Vojtech; Petrovici, Mihai; Petta, Catia; Peretti Pezzi, Rafael; Piano, Stefano; Pikna, Miroslav; Pillot, Philippe; Ozelin De Lima Pimentel, Lais; Pinazza, Ombretta; Pinsky, Lawrence; Pisano, Silvia; Piyarathna, Danthasinghe; Ploskon, Mateusz Andrzej; Planinic, Mirko; Pliquett, Fabian; Pluta, Jan Marian; Pochybova, Sona; Podesta Lerma, Pedro Luis Manuel; Poghosyan, Martin; Polishchuk, Boris; Poljak, Nikola; Poonsawat, Wanchaloem; Pop, Amalia; Poppenborg, Hendrik; Porteboeuf, Sarah Julie; Pozdniakov, Valeriy; Prasad, Sidharth Kumar; Preghenella, Roberto; Prino, Francesco; Pruneau, Claude Andre; Pshenichnov, Igor; Puccio, Maximiliano; Punin, Valery; Putschke, Jorn Henning; Raha, Sibaji; Rajput, Sonia; Rak, Jan; Rakotozafindrabe, Andry Malala; Ramello, Luciano; Rami, Fouad; Raniwala, Rashmi; Raniwala, Sudhir; Rasanen, Sami Sakari; Rascanu, Bogdan Theodor; Ratza, Viktor; Ravasenga, Ivan; Read, Kenneth Francis; Redlich, Krzysztof; Rehman, Attiq Ur; Reichelt, Patrick Simon; Reidt, Felix; Ren, Xiaowen; Renfordt, Rainer Arno Ernst; Reshetin, Andrey; Revol, Jean-pierre; Reygers, Klaus Johannes; Riabov, Viktor; Richert, Tuva Ora Herenui; Richter, Matthias Rudolph; Riedler, Petra; Riegler, Werner; Riggi, Francesco; Ristea, Catalin-lucian; Rode, Sudhir Pandurang; Rodriguez Cahuantzi, Mario; Roeed, Ketil; Rogalev, Roman; Rogochaya, Elena; Rohr, David Michael; Roehrich, Dieter; Rokita, Przemyslaw Stefan; Ronchetti, Federico; Dominguez Rosas, Edgar; Roslon, Krystian; Rosnet, Philippe; Rossi, Andrea; Rotondi, Alberto; Roukoutakis, Filimon; Roy, Christelle Sophie; Roy, Pradip Kumar; Vazquez Rueda, Omar; Rui, Rinaldo; Rumyantsev, Boris; Rustamov, Anar; Ryabinkin, Evgeny; Ryabov, Yury; Rybicki, Andrzej; Saarinen, Sampo; Sadhu, Samrangy; Sadovskiy, Sergey; Safarik, Karel; Saha, Sumit Kumar; Sahoo, Baidyanath; Sahoo, Pragati; Sahoo, Raghunath; Sahoo, Sarita; Sahu, Pradip Kumar; Saini, Jogender; Sakai, Shingo; Saleh, Mohammad Ahmad; Sambyal, Sanjeev Singh; Samsonov, Vladimir; Sandoval, Andres; Sarkar, Amal; Sarkar, Debojit; Sarkar, Nachiketa; Sarma, Pranjal; Sas, Mike Henry Petrus; Scapparone, Eugenio; Scarlassara, Fernando; Schaefer, Brennan; Scheid, Horst Sebastian; Schiaua, Claudiu Cornel; Schicker, Rainer Martin; Schmidt, Christian Joachim; Schmidt, Hans Rudolf; Schmidt, Marten Ole; Schmidt, Martin; Schmidt, Nicolas Vincent; Schukraft, Jurgen; Schutz, Yves Roland; Schwarz, Kilian Eberhard; Schweda, Kai Oliver; Scioli, Gilda; Scomparin, Enrico; Sefcik, Michal; Seger, Janet Elizabeth; Sekiguchi, Yuko; Sekihata, Daiki; Selyuzhenkov, Ilya; Senosi, Kgotlaesele; Senyukov, Serhiy; Serradilla Rodriguez, Eulogio; Sett, Priyanka; Sevcenco, Adrian; Shabanov, Arseniy; Shabetai, Alexandre; Shahoyan, Ruben; Shaikh, Wadut; Shangaraev, Artem; Sharma, Anjali; Sharma, Ankita; Sharma, Meenakshi; Sharma, Natasha; Sheikh, Ashik Ikbal; Shigaki, Kenta; Shimomura, Maya; Shirinkin, Sergey; Shou, Qiye; Shtejer Diaz, Katherin; Sibiryak, Yury; Siddhanta, Sabyasachi; Sielewicz, Krzysztof Marek; Siemiarczuk, Teodor; Silvermyr, David Olle Rickard; Simatovic, Goran; Simonetti, Giuseppe; Singaraju, Rama Narayana; Singh, Ranbir; Singh, Randhir; Singhal, Vikas; Sarkar - Sinha, Tinku; Sitar, Branislav; Sitta, Mario; Skaali, Bernhard; Slupecki, Maciej; Smirnov, Nikolai; Snellings, Raimond; Snellman, Tomas Wilhelm; Song, Jihye; Soramel, Francesca; Sorensen, Soren Pontoppidan; Sozzi, Federica; Sputowska, Iwona Anna; Stachel, Johanna; Stan, Ionel; Stankus, Paul; Stenlund, Evert Anders; Stocco, Diego; Storetvedt, Maksim Melnik; Strmen, Peter; Alarcon Do Passo Suaide, Alexandre; Sugitate, Toru; Suire, Christophe Pierre; Suleymanov, Mais Kazim Oglu; Suljic, Miljenko; Sultanov, Rishat; Sumbera, Michal; Sumowidagdo, Suharyo; Suzuki, Ken; Swain, Sagarika; Szabo, Alexander; Szarka, Imrich; Tabassam, Uzma; Takahashi, Jun; Tambave, Ganesh Jagannath; Tanaka, Naoto; Tarhini, Mohamad; Tariq, Mohammad; Tarzila, Madalina-gabriela; Tauro, Arturo; Tejeda Munoz, Guillermo; Telesca, Adriana; Terrevoli, Cristina; Teyssier, Boris; Thakur, Dhananjaya; Thakur, Sanchari; Thomas, Deepa; Thoresen, Freja; Tieulent, Raphael Noel; Tikhonov, Anatoly; Timmins, Anthony Robert; Toia, Alberica; Topilskaya, Nataliya; Toppi, Marco; Rojas Torres, Solangel; Tripathy, Sushanta; Trogolo, Stefano; Trombetta, Giuseppe; Tropp, Lukas; Trubnikov, Victor; Trzaska, Wladyslaw Henryk; Trzcinski, Tomasz Piotr; Trzeciak, Barbara Antonina; Tsuji, Tomoya; Tumkin, Alexandr; Turrisi, Rosario; Tveter, Trine Spedstad; Ullaland, Kjetil; Umaka, Ejiro Naomi; Uras, Antonio; Usai, Gianluca; Utrobicic, Antonija; Vala, Martin; Van Hoorne, Jacobus Willem; Van Leeuwen, Marco; Vande Vyvre, Pierre; Varga, Dezso; Diozcora Vargas Trevino, Aurora; Vargyas, Marton; Varma, Raghava; Vasileiou, Maria; Vasiliev, Andrey; Vauthier, Astrid; Vazquez Doce, Oton; Vechernin, Vladimir; Veen, Annelies Marianne; Vercellin, Ermanno; Vergara Limon, Sergio; Vermunt, Luuk; Vernet, Renaud; Vertesi, Robert; Vickovic, Linda; Viinikainen, Jussi Samuli; Vilakazi, Zabulon; Villalobos Baillie, Orlando; Villatoro Tello, Abraham; Vinogradov, Alexander; Virgili, Tiziano; Vislavicius, Vytautas; Vodopyanov, Alexander; Volkl, Martin Andreas; Voloshin, Kirill; Voloshin, Sergey; Volpe, Giacomo; Von Haller, Barthelemy; Vorobyev, Ivan; Voscek, Dominik; Vranic, Danilo; Vrlakova, Janka; Wagner, Boris; Wang, Hongkai; Wang, Mengliang; Watanabe, Yosuke; Weber, Michael; Weber, Steffen Georg; Wegrzynek, Adam; Weiser, Dennis Franz; Wenzel, Sandro Christian; Wessels, Johannes Peter; Westerhoff, Uwe; Whitehead, Andile Mothegi; Wiechula, Jens; Wikne, Jon; Wilk, Grzegorz Andrzej; Wilkinson, Jeremy John; Willems, Guido Alexander; Williams, Crispin; Willsher, Emily; Windelband, Bernd Stefan; Witt, William Edward; Xu, Ran; Yalcin, Serpil; Yamakawa, Kosei; Yano, Satoshi; Yin, Zhongbao; Yokoyama, Hiroki; Yoo, In-kwon; Yoon, Jin Hee; Yurchenko, Volodymyr; Zaccolo, Valentina; Zaman, Ali; Zampolli, Chiara; Correa Zanoli, Henrique Jose; Zardoshti, Nima; Zarochentsev, Andrey; Zavada, Petr; Zavyalov, Nikolay; Zbroszczyk, Hanna Paulina; Zhalov, Mikhail; Zhang, Xiaoming; Zhang, Yonghong; Zhang, Zuman; Zhao, Chengxin; Zherebchevskii, Vladimir; Zhigareva, Natalia; Zhou, Daicui; Zhou, You; Zhou, Zhuo; Zhu, Hongsheng; Zhu, Jianhui; Zhu, Ya; Zichichi, Antonino; Zimmermann, Markus Bernhard; Zinovjev, Gennady; Zmeskal, Johann; Zou, Shuguang

2018-01-01

The first measurements of anisotropic flow coefficients $v_{n}$ for mid-rapidity charged particles in Xe-Xe collisions at $\\sqrt{s_{NN}}=5.44$ TeV are presented. Comparing these measurements to those from Pb-Pb collisions at $\\sqrt{s_{NN}}=5.02$ TeV, $v_{2}$ is found to be suppressed for mid-central collisions at the same centrality, and enhanced for central collisions. The values of $v_{3}$ are generally larger in Xe-Xe than in Pb-Pb at a given centrality. These observations are consistent with expectations from hydrodynamic predictions. When both $v_{2}$ and $v_{3}$ are divided by their corresponding eccentricities for a variety of initial state models, they generally scale with transverse density when comparing Xe-Xe and Pb-Pb, with some deviations observed in central Xe-Xe and Pb-Pb collisions. These results assist in placing strong constraints on both the initial state geometry and medium response for relativistic heavy-ion collisions.

The 4s- and 4p- XPS spectra of Xe, XeF2 and XeF4

International Nuclear Information System (INIS)

Ohno, Masahide

2003-01-01

The 4s- and 4p- XPS spectra of Xe gas, XeF 2 molecule and XeF 4 molecule are calculated by an ab-initio atomic many-body theory. The 4s-peak and the prominent '4p'-peak are predicted well by the present theory. In XeF 2 and XeF 4 the spectral lines observed below the 4d-double ionization threshold are the 4d -2 4f multiplet states strongly perturbed by the interaction with the initial 4p 1/2 -hole state. They are very similar to the spectral lines which emerge with an increase in atomic number (e.g. Ba)

Geophysical logging and imaging of drillholes OL-KR45, OL-KR49, OL-KR50 and OL-KR50B at Olkiluoto in 2009

International Nuclear Information System (INIS)

Tarvainen, A.-M.

2010-04-01

Suomen Malmi Oy conducted geophysical drillhole logging, acoustic imaging and optical imaging of the drillholes OL-KR45 (re-measurements), OL-KR49, OL-KR50 and OL-KR50B at the Olkiluoto site in Eurajoki during January-November 2009. The survey is a part of Posiva Oy's detailed investigation program for the final disposal of spent nuclear fuel. The assignment included the field work and data processing. The report describes field operation, equipment as well as processing procedures and shows the obtained results and an analysis of their quality in the appendices. The raw and processed data are delivered digitally in WellCAD, PDF and Excel format. The missing density logging of drillhole OL-KR45 was carried out successfully. Dynamic rock mechanical parameters and natural gamma data were re-processed and this report includes updated WellCAD and Excel files. Acoustic imaging was also carried out in OL-KR45 after 700 meters depth. Acoustic imaging was used instead of optical imaging after 350 meters in OL-KR49 and 700 meters in OL-KR50. (orig.)

Compressibility and specific heats of heavier condensed rare gases near the liquid-vapour critical point

International Nuclear Information System (INIS)

March, N.H.

2003-08-01

Sarkisov (J. Chem. Phys. 119, 373, 2003) has recently discussed the structural behaviour of a simple fluid near the liquid-vapour critical point. His work, already compared with computer simulation studies, is here brought into direct contact for the heavier condensed rare gases Ar, Kr and Xe with (a) experiment and (b) earlier theoretical investigations. Directions for future studies then emerge. (author)

Thermal electron mobilities in low density gaseous mixtures

International Nuclear Information System (INIS)

Dmitriev, O.W.; Tchorzewska, W.; Szamrej, I.; Forys, M.

1992-01-01

A new method of obtaining thermal electron mobilities from experimental dependencies observed in the electron swarm is described; the method is suitable for both electron accepting and non-accepting systems. The electron mobilities for CO 2 , CH 4 C 2 H 6 as well as for N 2 , Ar, Xe, Kr and their mixtures with carbon dioxide are obtained. (Author)

Techniques for enhancing the performance of high charge state ECR ion sources

International Nuclear Information System (INIS)

Xie, Z.Q.

1999-01-01

Electron Cyclotron Resonance ion source (ECRIS), which produces singly to highly charged ions, is widely used in heavy ion accelerators and is finding applications in industry. It has progressed significantly in recent years thanks to a few techniques, such as multiple-frequency plasma heating, higher mirror magnetic fields and a better cold electron donor. These techniques greatly enhance the production of highly charged ions. More than 1 emA of He 2+ and O 6+ , hundreds of eμA of O 7+ , Ne 8+ , Ar 12+ , more than 100 eμA of intermediate heavy ions with charge states up to Ne 9+ , Ar 13+ , Ca 13+ , Fe 13+ , Co 14+ and Kr 18+ , tens of eμA of heavy ions with charge states up to Xe 28+ , Au 35+ , Bi 34+ and U 34+ were produced at cw mode operation. At an intensity of about 1 eμA, the charge states for the heavy ions increased up to Xe 36+ , Au 46+ , Bi 47+ and U 48+ . More than an order of magnitude enhancement of fully stripped argon ions was achieved (I≥0.1 and h;eμA). Higher charge state ions up to Kr 35+ , Xe 46+ and U 64+ at low intensities were produced for the first time from an ECRIS. copyright 1999 American Institute of Physics

Gaisma un krāsa sabiedriskās ēdināšanas telpās

OpenAIRE

Cvetkova, Diāna

2015-01-01

Diplomdarbā „Gaisma un krāsa sabiedriskās ēdināšanas telpās” autore analizē informāciju par apgaismojuma un krāsas lomām sabiedriskās ēdināšanas telpās. Labākam priekšstatam autore detāli apraksta to, kā apgaismojums un krāsa var izmainīt telpu un ietekmēt cilvēka psiholoģisko stāvokli un noskaņojumu, kā arī, kā noteiktas krasas apgaismojums var izmainīt ēdiena krāsu, tādējādi ietekmējot mūsu ēstgribu. Empiriskā daļā autore analizē interjerus kafejnīcās unrestorānos, kas atrodas Rīgas pi...

Determination of 131mXe and 133mXe in the presence of 133gXe via combined beta-spectroscopy and delayed coincidence

International Nuclear Information System (INIS)

Reeder, P.L.; Bowyer, T.W.; McIntyre, J.I.; Pitts, W.K.

2001-01-01

The International Monitoring System for the Comprehensive Nuclear-Test-Ban Treaty will include measurements of Xe fission products. Pacific Northwest National Laboratory has developed an automated system for separating Xe from air which detects Xe fission products using a beta-gamma counting system for 131m Xe, 133m Xe, 133g Xe, and 135g Xe. Betas and conversion electrons are detected in a plastic scintillation cell containing the Xe sample. Gamma and X-rays are detected in a NaI(Tl) scintillation detector which surrounds the plastic scintillator sample cell. Two-dimensional pulse-height spectra of gamma-energy versus beta-energy are obtained. The plastic scintillator spectrum in coincidence with the 31-keV X-rays from 131m Xe. 133m Xe, and 133g Xe is a complex mixture of conversion electrons and betas. A new technique to simultaneously measure the delayed coincidence (T 1/2 = 6.27 ns) between beta-particles from 133g Xe and conversion electrons depopulating the 81-keV state in 133 Cs is being developed. This technique allows separation of the 133g Xe beta spectrum from the conversion electrons due to 131m Xe and 133m Xe and uniquely quantifies all three nuclides. (author)

Determination of 131m Xe and 133m Xe in the presence of 133gXe via combined beta-spectroscopy and delayed coincidence

International Nuclear Information System (INIS)

Reeder, Paul L.; Bowyer, Ted W.; McIntyre, Justin I.; Pitts, W K.

2001-01-01

The International Monitoring System for the Comprehensive Nuclear-Test-Ban Treaty will include measurements of Xe fission products. Pacific Northwest National Laboratory has developed an automated system for separating Xe from air which detects Xe fission products using a beta-gamma counting system for 131mXe, 133mXe, 133Xe, and 135Xe. Betas and conversion electrons are detected in a plastic scintillation cell containing the Xe sample. Gamma and X-rays are detected in a NaI(Tl) scintillation detector which surrounds the plastic scintillator sample cell. Two-dimensional pulse height spectra of gamma energy versus beta energy are obtained. The plastic scintillator spectrum in coincidence with the 31-keV X-rays from 131mXe. 133mXe, and 133Xe is a complex mixture of conversion electrons and betas. A new technique to simultaneously measure the delayed coincidence (t1/2 = 6.27 ns) between beta particles from 133Xe and conversion electrons depopulating the 81-keV state in 133Cs is being developed. This technique will allow separation of the 133Xe spectrum from the conversion electrons due to 131mXe and 133mXe and will uniquely quantify all three nuclides

Excimer laser beam delivery systems for medical applications

Science.gov (United States)

Kubo, Uichi; Hashishin, Yuichi; Okada, Kazuyuki; Tanaka, Hiroyuki

1993-05-01

We have been doing the basic experiments of UV laser beams and biotissue interaction with both KrF and XeCl lasers. However, the conventional optical fiber can not be available for power UV beams. So we have been investigating about UV power beam delivery systems. These experiments carry on with the same elements doped quartz fibers and the hollow tube. The doped elements are OH ion, chlorine and fluorine. In our latest work, we have tried ArF excimer laser and biotissue interactions, and the beam delivery experiments. From our experimental results, we found that the ArF laser beam has high incision ability for hard biotissue. For example, in the case of the cow's bone incision, the incision depth by ArF laser was ca.15 times of KrF laser. Therefore, ArF laser would be expected to harden biotissue therapy as non-thermal method. However, its beam delivery is difficult to work in this time. We will develop ArF laser beam delivery systems.

Low-lying levels of 129Xe and 131Xe

International Nuclear Information System (INIS)

Palmer, D.C.; Irving, A.D.; Forsyth, P.D.; Hall, I.; Martin, D.G.E.; Maynard, M.J.

1978-01-01

The nuclei 129 Xe and 131 Xe have been studied by Coulomb excitation and by (α, n) reactions on 126 Te and 128 Te. Eleven new levels for 129 Xe and six for 131 Xe and B(E2) transition values for some of the low-lying states are reported. The present Coulomb excitation experiments together with published β-decay work enable some spin-parity assignments and restrictions to be made. The data are broadly consistent with the predictions of the particle-vibrator coupling model, although a thorough comparison requires further spectroscopic measurements and more detailed theoretical calculation. (author)

Calculation of a complete data set for n + 83Kr, 84Kr, 85Kr and 86Kr in the energy region 0.001-20 MeV

International Nuclear Information System (INIS)

Cai Chonghai

1999-01-01

Complete reaction cross sections, secondary neutron spectra and elastic scattering angular distributions of 83 Kr, 84 Kr, 85 Kr and 86 Kr in the energy region 0.001-20 MeV are calculated, theoretical results are in ENDF/B-6 in pretty good accordance with experimental data

Hydrodynamic predictions for 5.44 TeV Xe+Xe collisions

Science.gov (United States)

Giacalone, Giuliano; Noronha-Hostler, Jacquelyn; Luzum, Matthew; Ollitrault, Jean-Yves

2018-03-01

We argue that relativistic hydrodynamics is able to make robust predictions for soft particle production in Xe+Xe collisions at the CERN Large Hadron Collider (LHC). The change of system size from Pb+Pb to Xe+Xe provides a unique opportunity to test the scaling laws inherent to fluid dynamics. Using event-by-event hydrodynamic simulations, we make quantitative predictions for several observables: mean transverse momentum, anisotropic flow coefficients, and their fluctuations. Results are shown as a function of collision centrality.

Investigating the Effect of the Binary Mixtures Composition of Noble Gases on Their Thermodynamic and Transport Properties

Directory of Open Access Journals (Sweden)

S. A. Burtsev

2015-01-01

Full Text Available The paper presents possible application fields of the binary noble gas mixtures with low Prandtl numbers. It shows that it is expedient to select these mixtures as the working fluids for closed Brayton cycle gas-turbine installations, thermo-acoustic engines and for the gas dynamic energy separation device (Leontiev tube. As follows from the analysis, He-Ar, He-Kr, and HeXe mixtures have proven to be the most attractive choice. The paper has analyzed the calculation results for coefficient of dynamic viscosity, coefficient of thermal conductivity, and for heat capacity at constant pressure for the given mixtures in terms of mixture molecular weights at pressures of 2MPa and 7MPa and temperatures of 400 and 1200°K. According to data of experiments and calculations available in public sources published by another authors, the results are verified. It was found that at constant pressure within the examined range of parameters (i.e. pressure, temperature, mixture molecular weight the obtained heat capacity values are in good agreement with the values of the verification data. In calculating dynamic viscosity coefficient for any pressure and temperature the utilized technique provides results for He-Ar and He-Kr mixtures within the entire range of the molecular weights, which are, essentially, as good as shown by international verification techniques. However, at high pressures and low temperatures for He-Xe mixture with molecular weights close to the pure Xe the divergence was found to be as high as 25 % while for other parameter intervals under consideration and with the same mixture the difference does not exceed 10 %. A good agreement with the verification data is observed for the values of a thermal conductivity coefficient of He-Ar and He-Kr mixtures for any value of parameters, while for He-Xe mixture with molecular weights close to 60 g/mole independently of pressure the divergence can reach 30 % for 1200°K and 20 % for 400°K. It is shown

Multi-quantum excitation in optically pumped alkali atom: rare gas mixtures

Science.gov (United States)

Galbally-Kinney, K. L.; Rawlins, W. T.; Davis, S. J.

2014-03-01

Diode-pumped alkali laser (DPAL) technology offers a means of achieving high-energy gas laser output through optical pumping of the D-lines of Cs, Rb, and K. The exciplex effect, based on weak attractive forces between alkali atoms and polarizable rare gas atoms (Ar, Kr, Xe), provides an alternative approach via broadband excitation of exciplex precursors (XPAL). In XPAL configurations, we have observed multi-quantum excitation within the alkali manifolds which result in infrared emission lines between 1 and 4 μm. The observed excited states include the 42FJ states of both Cs and Rb, which are well above the two-photon energy of the excitation laser in each case. We have observed fluorescence from multi-quantum states for excitation wavelengths throughout the exciplex absorption bands of Cs-Ar, Cs-Kr, and Cs-Xe. The intensity scaling is roughly first-order or less in both pump power and alkali concentration, suggesting a collisional energy pooling excitation mechanism. Collisional up-pumping appears to present a parasitic loss term for optically pumped atomic systems at high intensities, however there may also be excitation of other lasing transitions at infrared wavelengths.

Ion mobilities in Xe/Ne and other rare-gas mixtures

Energy Technology Data Exchange (ETDEWEB)

Piscitelli, D; Pitchford, L C [Centre de Physique des Plasmas et Applications de Toulouse (CPAT), UMR 5002 CNRS, 118 route de Narbonne, 31062 Toulouse (France); Phelps, A V [JILA, University of Colorado and National Institute of Technology, Boulder, Colorado (United States); Urquijo, J de [Centro de Ciencias Fisicas, Universidad Nacional Autonoma de Mexico, Post Office Box 48-3, 62251, 80309-0440 Cuernavaca, Moreno (Mexico); Basurto, E [Departmento de Ciencias Basicas, Universidad Autonoma Metropolitana, 02200 Mexico Distrito Federal (Mexico)

2003-10-01

The ion mobility or drift velocity data important for modeling glow discharges in rare gas mixtures are not generally available, nor are the ion-neutral scattering cross sections needed to calculate these data. In this paper we propose a set of cross sections for Xe{sup +} and Ne{sup +} collisions with Xe and Ne atoms. Ion mobilities at 300 K calculated using this cross section set in a Monte Carlo simulation are reported for reduced field strengths, E/N, up to 1500x10{sup -21} V m{sup 2}, in pure gases and in Xe/Ne mixtures containing 5% and 20% Xe/Ne, which are mixtures of interest for plasma display panels (PDPs). The calculated Xe{sup +} mobilities depend strongly on the mixture composition, but the Ne{sup +} mobility varies only slightly with increasing Xe in the mixture over the range studied here. The mobilities in pure gases compare well with available experimental values, and mobilities in gas mixtures at low E/N compare well with our recent measurements which will be published separately. Results from these calculations of ion mobilities are used to evaluate the predictions of Blanc's law and of the mixture rule proposed by Mason and Hahn [Phys. Rev. A 5, 438 (1972)] for determining the ion mobilities in mixtures from a knowledge of the mobilities in each of the pure gases. The mixture rule of Mason and Hahn is accurate to better than 10% at high field strengths over a wide range of conditions of interest for modeling PDPs. We conclude that a good estimate of ion mobilities at high E/N in Xe/Ne and other binary rare gas mixtures can be obtained using this mixture rule combined with known values of mobilities in parent gases and with the Langevin form for mobility of rare gas ions ion in other gases. This conclusion is supported by results in Ar/Ne mixtures which are also presented here.

Study of Pair and many-body interactions in rare-gas halide atom clusters using negative ion zero electron kinetic energy (ZEKE) and threshold photodetachment spectroscopy

Energy Technology Data Exchange (ETDEWEB)

Yourshaw, Ivan [Univ. of California, Berkeley, CA (United States)

1998-07-09

The diatomic halogen atom-rare gas diatomic complexes KrBr^-, XeBr^-, and KrCl^- are studied in this work by zero electron kinetic energy (ZEKE) spectroscopy in order to characterize the weak intermolecular diatomic potentials of these species. Also, the ZEKE and threshold photodetachment spectra of the polyatomic clusters Ar_nBr^- (n = 2-9) and Ar_nI^- (n = 2-19) are studied to obtain information about the non-additive effects on the interactions among the atoms. This work is part of an ongoing effort to characterize the pair and many-body potentials of the complete series of rare gas halide clusters. In these studies we obtain information about both the anionic and neutral clusters.

Doubly differential detachment cross sections for fast H---rare-gas collisions

International Nuclear Information System (INIS)

Liu, C.; Starace, A.F.

1990-01-01

Detailed theoretical analyses are presented of the projectile-energy dependence as well as the target dependence of the electron-detachment collision processes, H - +T→H(n=2)+T * +e - . These analyses are illustrated by calculations of both projectile-frame and laboratory-frame doubly differential cross sections (DDCS's) for 0.5-, 1.0-, and 1.5-MeV H - collisions with He targets and for 0.5-MeV H - collisions with Ne, Ar, Kr, and Xe targets; in addition, we present laboratory frame DDCS's for 0.1-MeV H - collisions with Xe targets. Comparisons with available experimental data are given

Geophysical drillhole logging and imaging of drillholes OL-KR51, OL-KR52, OL-KR52B, OL-KR53 and OL-KR53B at Olkiluoto in 2009 and 2010

International Nuclear Information System (INIS)

Tarvainen, A.-M.

2010-10-01

Suomen Malmi Oy conducted geophysical drillhole logging and optical imaging of the drillholes OL-KR51, OL-KR52, OL-KR52B, OL-KR53 and OL-KR53B at the Olkiluoto site in Eurajoki between November 2009 and February 2010. The survey is a part of Posiva Oy's detailed investigation program for the final disposal of spent nuclear fuel. The assignment included the field work and data processing. The report describes field operation, equipment as well as processing procedures and shows the obtained results and an analysis of their quality in the appendices. The raw and processed data are delivered digitally in WellCAD, PDF and Excel format. (orig.)

A Density Functional Theory Evaluation of Hydrophobic Solvation: Ne, Ar and Kr in a 50-Water Cluster. Implications for the Hydrophobic Effect.

Science.gov (United States)

Kobko, Nadya; Marianski, Mateusz; Asensio, Amparo; Wieczorek, Robert; Dannenberg, J J

2012-06-15

The physical explanation for the hydrophobic effect has been the subject of disagreement. Physical organic chemists tend to use a explanation related to pressure, while many biochemists prefer an explanation that involves decreased entropy of the aqueous solvent. We present DFT calculations at the B3LYP/6-31G(d,p) and X3LYP/6-31G(d,p) levels on the solvation of three noble gases (Ne, Ar, and Kr) in clusters of 50 waters. Vibrational analyses show no substantial decreases in the vibrational entropies of the waters in any of the three clusters. The observed positive free energies of transfer from the gas phase or from nonpolar solvents to water appear to be due to the work needed to make a suitable hole in the aqueous solvent. We distinguish between hydrophobic solvations (explicitly studied here) and the hydrophobic effect that occurs when a solute (or transition state) can decrease its volume through conformational change (which is not possible for the noble gases).

Characterization of DC magnetron plasma in Ar/Kr/N2 mixture during deposition of (Cr,Al)N coating

International Nuclear Information System (INIS)

Bobzin, K; Bagcivan, N; Theiß, S; Brugnara, R; Bibinov, N; Awakowicz, P

2017-01-01

Reactive sputter deposition of (Cr,Al)N coatings in DC magnetron plasmas containing Ar/Kr/N 2 mixtures is characterized by applying a combination of voltage–current measurement, optical emission spectroscopy (OES) and numerical simulation. Theoretical and experimental methods supplement each other and their combination permits us to obtain the most reliable information about the processes by physical vapor deposition. Gas temperature ( T g ) and plasma parameters, namely electron density n e and electron temperature T e are determined by spatial resolved measurements of molecular nitrogen photoemission. Steady-state densities of Cr and Al atoms are measured using OES. The sputtering of Cr and Al atoms is simulated using the TRIDYN code, measured electric current and applied voltage. Transport of sputtered atoms through the plasma volume is simulated by adopting a Monte-Carlo code. In order to quantify the ‘poisoning’ of the target surface with nitrogen, simulated steady state densities of Al and Cr atoms at different states of poisoning and at different distances from the target are compared with the measured densities. In addition, simulated fluxes of Cr and Al atoms to the substrate are compared with the measured deposition rates of the (Cr,Al)N coating. (paper)

Ion beam mixing of titanium films on stainless steel

International Nuclear Information System (INIS)

Bolse, W.; Weber, T.

1990-01-01

The ion mixing of Ti-steel bilayers with N + , Ar + , Ti + , Kr + and Xe + ions was investigated by means of Rutherford backscattering spectroscopy (RBS). The mixing rates exhibit a linear scaling with the deposited damage energy F D . No correlation between the properties of the mixing ion and the mixing efficiency was found. The results are compared with the predictions of ballistic and thermal-spike models. (orig.)

Electron scattering in dense atomic and molecular gases: An empirical correlation of polarizability and electron scattering length

International Nuclear Information System (INIS)

Rupnik, K.; Asaf, U.; McGlynn, S.P.

1990-01-01

A linear correlation exists between the electron scattering length, as measured by a pressure shift method, and the polarizabilities for He, Ne, Ar, Kr, and Xe gases. The correlative algorithm has excellent predictive capability for the electron scattering lengths of mixtures of rare gases, simple molecular gases such as H 2 and N 2 and even complex molecular entities such as methane, CH 4

Phase transitions in two-dimensional systems

International Nuclear Information System (INIS)

Salinas, S.R.A.

1983-01-01

Some experiences are related using synchrotron radiation beams, to characterize solid-liquid (fusion) and commensurate solid-uncommensurate solid transitions in two-dimensional systems. Some ideas involved in the modern theories of two-dimensional fusion are shortly exposed. The systems treated consist of noble gases (Kr,Ar,Xe) adsorbed in the basal plane of graphite and thin films formed by some liquid crystal shells. (L.C.) [pt

Argon defect complexes in low energy Ar irradiated molybdenum

International Nuclear Information System (INIS)

Veen, A. van; Buters, W.T.M.; Kolk, G.J. van der; Caspers, L.M.; Armstrong, T.R.

1982-01-01

Thermal desorption spectrometry has been used to study the defects created in Mo irradiated along the direction with Ar ions ranging in energy from 0.1 to 2 keV. In addition to monitoring the release of the implanted Ar, additional information has been obtained by decoration of the defects with low energy helium and subsequent monitoring of the helium release. The studies show evidence that the Ar can be trapped in both substitutional sites and in a configuration in which the Ar is associated with vacancies (ArVsub(n), n >= 2). Most of the Ar implanted at high energy is released at approx. equal to 1500 K by thermal vacancy assisted diffusion. Argon trapped closer to the surface is released at lower temperatures via at least three different surface related release mechanisms. Additional results are presented on the interaction of self interstitial atoms (introduced by 100 eV Xe bombardment) with the Ar defects. Substitutional Ar is found to convert to interstitial Ar which seems to be mobile at room temperature. The Ar-vacancy complexes are found to be reduced to substitutional Ar. The results of atomistic calculations of the release mechanisms will also be presented. (orig.)

Inner-shell photoionization and core-hole decay of Xe and XeF2.

Science.gov (United States)

Southworth, Stephen H; Wehlitz, Ralf; Picón, Antonio; Lehmann, C Stefan; Cheng, Lan; Stanton, John F

2015-06-14

Photoionization cross sections and partial ion yields of Xe and XeF2 from Xe 3d(5/2), Xe 3d(3/2), and F 1s subshells in the 660-740 eV range are compared to explore effects of the F ligands. The Xe 3d-ϵf continuum shape resonances dominate the photoionization cross sections of both the atom and molecule, but prominent resonances appear in the XeF2 cross section due to nominal excitation of Xe 3d and F 1s electrons to the lowest unoccupied molecular orbital (LUMO), a delocalized anti-bonding MO. Comparisons of the ion products from the atom and molecule following Xe 3d photoionization show that the charge-state distribution of Xe ions is shifted to lower charge states in the molecule along with production of energetic F(+) and F(2+) ions. This suggests that, in decay of a Xe 3d core hole, charge is redistributed to the F ligands and the system dissociates due to Coulomb repulsion. The ion products from excitation of the F 1s-LUMO resonance are different and show strong increases in the yields of Xe(+) and F(+) ions. The subshell ionization thresholds, the LUMO resonance energies, and their oscillator strengths are calculated by relativistic coupled-cluster methods and agree well with measurements.

Recombination of KrD{sup +} and KrH{sup +} ions in afterglow plasma

Energy Technology Data Exchange (ETDEWEB)

Korolov, I; Kotrik, T; Plasil, R; Hejduk, M; Varju, J; Dohnal, P; Glosik, J, E-mail: juraj.glosik@mff.cuni.c [Department of Surface and Plasma Science, Faculty of Mathematics and Physics, Charles University in Prague (Czech Republic)

2009-11-15

Reported is flowing afterglow (FALP) study of recombination of KrH{sup +} and KrD{sup +} ions with electrons at 250 K in mixtures of He/Kr/H{sub 2} and He/Kr/D{sub 2}, respectively. The influence of fast recombining cluster ions formation on apparent effective recombination rate coefficients ({alpha}{sub eff}) was measured and used in data analysis. The obtained binary rate coefficients for recombination of KrH{sup +} and KrD{sup +} are {alpha}{sub KrH+} = 2x10{sup -8} cm{sup 3}s{sup -1} and {alpha}{sub KrD+} = 1x10{sup -8} cm{sup 3}s{sup -1}.

Trapping of He clusters by inert-gas impurities in tungsten: First-principles predictions and experimental validation

Energy Technology Data Exchange (ETDEWEB)

Nguyen-Manh, Duc, E-mail: duc.nguyen@ccfe.ac.uk; Dudarev, S.L.

2015-06-01

Properties of point defects resulting from the incorporation of inert-gas atoms in bcc tungsten are investigated systematically using first-principles density functional theory (DFT) calculations. The most stable configuration for the interstitial neon, argon, krypton and xenon atoms is the tetrahedral site, similarly to what was found earlier for helium in W. The calculated formation energies for single inert-gas atoms at interstitial sites as well as at substitutional sites are much larger for Ne, Ar, Kr and Xe than for He. While the variation of the energy of insertion of inert-gas defects into interstitial configurations can be explained by a strong effect of their large atomic size, the trend exhibited by their substitutional energies is more likely related to the covalent interaction between the noble gas impurity atoms and the tungsten atoms. There is a remarkable variation exhibited by the energy of interaction between inert-gas impurities and vacancies, where a pronounced size effect is observed when going from He to Ne, Ar, Kr, Xe. The origin of this trend is explained by electronic structure calculations showing that p-orbitals play an important part in the formation of chemical bonds between a vacancy and an atom of any of the four inert-gas elements in comparison with helium, where the latter contains only 1s{sup 2} electrons in the outer shell. The binding energies of a helium atom trapped by five different defects (He-v, Ne-v, Ar-v, Kr-v, Xe-v, where v denotes a vacancy in bcc-W) are all in excellent agreement with experimental data derived from thermal desorption spectroscopy. Attachment of He clusters to inert gas impurity atom traps in tungsten is analysed as a function of the number of successive trapping helium atoms. Variation of the Young modulus due to inert-gas impurities is analysed on the basis of data derived from DFT calculations.

Charge-state distribution measurements of ^{238}U and ^{136}Xe at 11  MeV/nucleon using gas charge stripper

Directory of Open Access Journals (Sweden)

H. Kuboki

2010-09-01

Full Text Available The charge-state distributions and equilibrium charge states of uranium (^{238}U and xenon (^{136}Xe ions at 11  MeV/nucleon were determined using a gas charge stripper. A differential pumping system facilitated the increase of the nitrogen gas thickness up to 1.3  mg/cm^{2}, which is sufficient for the most probable charge state to attain equilibrium. The charge states of ^{238}U attain equilibrium at 56.0, 56.6, and 55.7 in N_{2}, Ar, and CO_{2} media with thicknesses of 125, 79, and 126  μg/cm^{2}, respectively, while those of ^{136}Xe attain equilibrium at 40.5, 40.1, and 40.3 in N_{2}, Ar, and CO_{2} media with thicknesses of 163, 95, and 139  μg/cm^{2}, respectively. The equilibrium charge states of ^{136}Xe are acceptable for acceleration by the subsequent cyclotron. The measured data of ^{238}U were used to devise an empirical formula for the prediction of the equilibrium charge state in gaseous media over the energy region of 0.01–60  MeV/nucleon. The equilibrium charge state of ^{136}Xe as predicted by the devised formula is in good agreement with the data.

Post-irradiation analysis of an ISOLDE lead-bismuth target: Stable and long-lived noble gas nuclides

Energy Technology Data Exchange (ETDEWEB)

Leya, I., E-mail: Ingo.Leya@space.unibe.ch [University of Bern, Space Science and Planetology, Bern (Switzerland); Grimberg, A. [University of Bern, Space Science and Planetology, Bern (Switzerland); Isotope Geochemistry, ETH Zürich, Zürich (Switzerland); David, J.-C. [CEA/Saclay, Irfu/SPhN, 91191 Gif-sur-Yvette, Cedex (France); Schumann, D.; Neuhausen, J. [Paul Scherrer Institut, Villigen (Switzerland); Zanini, L. [Paul Scherrer Institut, Villigen (Switzerland); European Spallation Source ESS AB, P.O. Box 117, SE-22100 Lund (Sweden); Noah, E. [University of Geneva, Département de Physique Nucléaire et Corpusculaire, Geneve (Switzerland)

2016-07-15

We measured the isotopic concentrations of long-lived and stable He, Ne, Ar, Kr, and Xe isotopes in a sample from a lead-bismuth eutectic target irradiated with 1.0 and 1.4 GeV protons. Our data indicate for most noble gases nearly complete release with retention fractions in the range of percent or less. Higher retention fractions result from the decay of long-lived radioactive progenitors from groups 1, 2, or 7 of the periodic table. From the data we can calculate a retention fraction for {sup 3}H of 2–3%. For alkaline metals we find retention fractions of about 10%, 30%, and 50% for Na, Rb, and Cs, respectively. For the alkaline earth metal Ba we found complete retention. Finally, the measured Kr and Xe concentrations indicate that there was some release of the halogens Br and I during and/or after the irradiation.

First-principles study of noble gas stability in ThO{sub 2}

Energy Technology Data Exchange (ETDEWEB)

Shao, Kuan [Shanghai Institute of Applied Physics, Chinese Academy of Sciences, Shanghai 201800 (China); University of Chinese Academy of Sciences, Beijing 100049 (China); Han, Han, E-mail: hanhanfudan@gmail.com [Shanghai Institute of Applied Physics, Chinese Academy of Sciences, Shanghai 201800 (China); Zhang, Wei [Shanghai Institute of Applied Physics, Chinese Academy of Sciences, Shanghai 201800 (China); Key Laboratory of Interfacial Physics and Technology, Chinese Academy of Sciences, Shanghai 201800 (China); Wang, Hui [School of Physics and Engineering, Henan University of Science and Technology, Luoyang 471003 (China); Wang, Chang-Ying; Guo, Yong-Liang [Shanghai Institute of Applied Physics, Chinese Academy of Sciences, Shanghai 201800 (China); Ren, Cui-Lan [Shanghai Institute of Applied Physics, Chinese Academy of Sciences, Shanghai 201800 (China); Key Laboratory of Interfacial Physics and Technology, Chinese Academy of Sciences, Shanghai 201800 (China); Huai, Ping, E-mail: huaiping@sinap.ac.cn [Shanghai Institute of Applied Physics, Chinese Academy of Sciences, Shanghai 201800 (China)

2017-07-15

The stability of noble gases (He, Ne, Ar, Kr and Xe) in thorium dioxide is studied by means of density functional theory. The computations are performed considering insertion sites of ThO{sub 2}, including the interstitial sites, the thorium vacancies, the oxygen-thorium di-vacancy and three types of Schottky defects. Our results show that there is an approximately linear relation between the energies and the atomic radii. As the size of the noble gas atom increases, the noble gas atoms energetically prefer to incorporate into large vacancy defects rather than into interstitial positions. Moreover, the binding energy of Kr or Xe interstitial in a Schottky defect is larger than the formation energy of a Schottky defect, suggesting the Schottky defects are thermodynamically favorable in the presence of these noble gas atoms. The charged defects are also considered for noble gas atoms trapped in Th and O vacancies.

Multiple Tracer ({sup 4}He, {sup 14}C, {sup 39}Ar, {sup 3}H/{sup 3}He, {sup 85}Kr) Depth Profile in an Extensively Exploited Multilevel Aquifer System in the Venetian Plain, Italy

Energy Technology Data Exchange (ETDEWEB)

Mayer, A.; Claude, C [Centre Europeen de Recherche et d' Enseignement des Geosciences de l' Environnement, Aix-en-Provence (France); Purtschert, R. [Climate and Environmental Physics, University of Bern (Switzerland); Sueltenfuss, J. [Institute of Environmental Physics, University of Bremen (Germany); Travi, Y. [UMR-EMMAH, Universite d' Avignon et des Pays de Vaucluse, Avignon (France)

2013-07-15

Individual dating tracers have their specific inherent properties, advantages and limitations. Apparent {sup 4}He accumulation ages are biased as a function of a prior unknown external helium influx; {sup 14}C (T{sub 1/2}: 5730 a) dating in groundwater requires suitable geochemical correction schemes and {sup 39}Ar (T{sub 1/2}: 269 a) may be affected by underground production. In a multiple tracer study in the Venetian Plain, Italy, using {sup 4}He, {sup 14}C. {sup 39}Ar {sup 3}H/{sup 3}He and {sup 85}Kr data, the groundwater residence times in a depth profile consisting of different separated aquifers between 50-350 m depth are estimated. Moreover, limitations and uncertainties of the applied tracer methods are identified, assessed and quantified. (author)

Comprehensive sets of 124Xe(n ,γ )125Xe and 124Xe(n ,2 n )123Xe cross-section data for assessment of inertial-confinement deuterium-tritium fusion plasma

Science.gov (United States)

Bhike, Megha; Fallin, B.; Gooden, M. E.; Ludin, N.; Tornow, W.

2015-01-01

Measurements of the neutron radiative-capture cross section of 124Xe have been performed for the first time for neutron energies above 100 keV. In addition, data for the 124Xe(n ,2 n )123Xe reaction cross section have been obtained from threshold to 14.8 MeV to cover the entire energy range of interest, while previous data existed only at around 14 MeV. The results of these measurements provide the basis for an alternative and sensitive diagnostic tool for investigating properties of the inertial confinement fusion plasma in deuterium-tritium (DT) capsules at the National Ignition Facility located at Lawrence Livermore National Laboratory. Here, areal density ρ R (density × radius) of the fuel, burn asymmetry, and fuel-ablator mix are of special interest. The 124Xe(n ,γ )125Xe reaction probes the down-scattered neutrons, while the 124Xe(n ,2 n )123Xe reaction provides a measure of the 14 MeV direct neutrons.

Sputtering gases and pressure effects on the microstructure, magnetic properties and recording performance of TbFeCo films

International Nuclear Information System (INIS)

Murakami, Motoyoshi; Birukawa, Masahiro

2008-01-01

The MsHc value is considered to be a key factor in high-density recording, and controlling the microstructure on the magnetic underlayer was found to be an effective way of increasing the MsHc of the amorphous TbFeCo magneto-optical (MO) medium. In this paper, we investigate the TbFeCo film's magnetic properties and the effects on the microcolumnar structure, which depends on the sputtering conditions of using various sputtering gases including Ar, Kr, and Xe, and the recording characteristics of TbFeCo memory layers. With heavy sputtering gases such as Kr or Xe, the columnar structure can be prepared in a TbFeCo film at a pressure lower than 1.0 Pa. The columnar structure of a recording layer can be effectively formed thanks to the effects of the magnetic underlayer, which has a fine surface even in the sputtering process in which Xe gas is used. The above applies to the sputtering process in which Ar gas is used. Also, when Xe gas is used in the sputtering process, coercivity Hc is increased through the formation of a well-segregated microcolumnar structure built on domain wall pinning sites, and we obtain a large MsHc and a high squareness ratio of the Kerr-hysteresis loop. Our results indicate that processing a TbFeCo film with heavy sputtering gases is suitable for tiny mark stability because the temperature gradient of Hc is increased. The objective of the low-pressure sputtering process using Xe gas to produce the columnar structure is to achieve ultra-high-density recording with tiny mark stability in the TbFeCo medium. This has been confirmed with magnetic force microscope (MFM) images of stable tiny marks recorded on TbFeCo film

Ab initio effective core potentials including relativistic effects. II. Potential energy curves for Xe2, Xe+2, and Xe*2

International Nuclear Information System (INIS)

Ermler, W.C.; Lee, Y.S.; Pitzer, K.S.; Winter, N.W.

1978-01-01

Potential energy curves for the ground 1 Σ + /sub g/ state of Xe 2 , the first four states of the Xe + 2 ions, and the eight Xe* 2 excimer states corresponding to the addition of a 6ssigma/sub g/ Rydberg electron to these ion cores have been computed using averaged relativistic effective core potentials (AREP) and the self-consistent field approximation for the valence electrons. The calculations were carried out using the LS-coupling scheme with the effects of spin--orbit coupling included in the resulting potential energy curves using an empirical procedure. A comparison of nonrelativistic and averaged relativistic EP's and subsequent molecular calculations indicates that relativistic effects arising from the mass--velocity and Darwin terms are not important for these properties of Xe 2 molecules. Spectroscopic constants for Xe + 2 are in good agreement with all electron CI calculations suggesting that the computed values for Xe* 2 excimers should be reliable. The lifetime for the O/sub u/ + state of the Xe 2 * is computed to be 5.6 nsec which is in the range of the experimentally determined values

Vibrational relaxation of matrix-isolated CH3F and HCl

International Nuclear Information System (INIS)

Young, L.

1981-08-01

Kinetic and spectroscopic studies have been performed on CH 3 F and HCl as a function of host matrix and temperature. Temporally and spectrally resolved infrared fluorescence was used to monitor the populations of both the initially excited state and the lower lying levels which participate in the relaxation process. For CH 3 F, relaxation from any of the levels near 3.5 μ, i.e. the CH stretching fundamentals or bend overtones, occurs via rapid ( 3 with subsequent relaxation of the ν 3 (CF stretch) manifold. Lifetimes of 2ν 3 and ν 3 were determined through overtone, ΔV = 2, and fundamental fluorescence. These lifetimes show a dramatic dependence on host lattice, an increase of two orders of magnitude in going from Xe and Ar matrices. Lifetimes depend only weakly on temperature. The relaxation of 2ν 3 and ν 3 is consistent with a model in which production of a highly rotationally excited guest via collisions with the repulsive wall of the host is the rate limiting step. For HCl, lifetimes of v = 1,2,3 have been determined. In all hosts, the relaxation is non-radiative. For a given vibrational state, v, the relaxation rate increases in the series k(Ar) < k(Kr) < k(Xe). The dependence of the relaxation rate; on v is superlinear in all matrices, the deviation from linearity increasng in the order Ar < Kr < Xe. The relaxation rates become more strongly temperature dependent with increasing vibrational excitation. The results are consistent with a mechanism in which complex formation introduces the anisotropy necessary to induce a near resonant V → R transition in the rate limiting step

Stark shift measurements of Xe II and Xe III spectral lines

International Nuclear Information System (INIS)

Cirisan, M; Pelaez, R J; Djurovic, S; Aparicio, J A; Mar, S

2007-01-01

Stark shift measurements of singly and doubly ionized Xe spectral lines are presented in this paper. Shifts of 110 Xe II lines and 42 Xe III lines are reported, including a significant number of new results. A low-pressure-pulsed arc with 95% of He and 5% of Xe was used as a plasma source. All measurements were performed under the following plasma conditions: electron density (0.2-1.4) x 10 23 m -3 and electron temperature 18 000-23 000 K. The measured Stark shifts are compared with other experimental and theoretical data

Mise-a-la-masse measurements in drillholes OL-KR4, OL-KR30 and OL-KR14 - OL-KR18 in Olkiluoto

International Nuclear Information System (INIS)

Kristiansson, S.; Heikkinen, P.

2009-02-01

Mise-a-la-masse measurements were conducted in the Olkiluoto investigation site in the time period from May to November 2007. Measurements were carried out in drillholes OL-KR4, OL-KR30 and OL-KR14 - OL-KR18. The purpose of the study was to collect data for geological modelling. The aim is to evaluate the continuity of fractures and other geological structures from a drillhole to another drillhole and from a drillhole to the ground surface. Posiva has developed electrodes for mise-a-la-masse method measurements, where the location of the electrode is between rubber disks similar to the flow guide. Rubber disks prevent leakage of current along the drillhole and focus current directly to a specific fracture. (orig.)

Elastic scattering of 40Ar and 84Kr on 209Bi and 238U at 7.2 and 8.5 MeV/N

International Nuclear Information System (INIS)

Birkelund, J.R.; Huizenga, J.R.; Freiesleben, H.; Wolf, K.L.; Unik, J.P.; Viola, V.E. Jr.

1976-01-01

Cross sections for elastic scattering of 40 Ar on targets of 209 Bi and 238 U were measured at energies of 286 and 340 MeV. Cross sections for the elastic scattering of 84 Kr on 209 Bi were measured at energies of 600 and 712 MeV. These experimental elastic scattering data were fitted with optical and Fresnel models. The total reaction cross section deduced from the Fresnel model by the one-quarter point technique agrees within a few percent with the result from the optical model. The Fresnel interaction radius and the optical model strong absorption radius are found to be approximately equal and qualitatively reproduced by the sum of the half-density electron scattering radii of the two heavy ions and a constant of 3.2+-0.3 fm. A method of estimating total reaction cross sections for heavy ions is presented. Some observations on the real and imaginary potentials of very heavy ions are presented

Mechanism and computational model for Lyman-α-radiation generation by high-intensity-laser four-wave mixing in Kr-Ar gas

Science.gov (United States)

Louchev, Oleg A.; Bakule, Pavel; Saito, Norihito; Wada, Satoshi; Yokoyama, Koji; Ishida, Katsuhiko; Iwasaki, Masahiko

2011-09-01

We present a theoretical model combined with a computational study of a laser four-wave mixing process under optical discharge in which the non-steady-state four-wave amplitude equations are integrated with the kinetic equations of initial optical discharge and electron avalanche ionization in Kr-Ar gas. The model is validated by earlier experimental data showing strong inhibition of the generation of pulsed, tunable Lyman-α (Ly-α) radiation when using sum-difference frequency mixing of 212.6 nm and tunable infrared radiation (820-850 nm). The rigorous computational approach to the problem reveals the possibility and mechanism of strong auto-oscillations in sum-difference resonant Ly-α generation due to the combined effect of (i) 212.6-nm (2+1)-photon ionization producing initial electrons, followed by (ii) the electron avalanche dominated by 843-nm radiation, and (iii) the final breakdown of the phase matching condition. The model shows that the final efficiency of Ly-α radiation generation can achieve a value of ˜5×10-4 which is restricted by the total combined absorption of the fundamental and generated radiation.

Mechanism and computational model for Lyman-{alpha}-radiation generation by high-intensity-laser four-wave mixing in Kr-Ar gas

Energy Technology Data Exchange (ETDEWEB)

Louchev, Oleg A.; Saito, Norihito; Wada, Satoshi [Advanced Science Institute, RIKEN, 2-1 Hirosawa, Wako, Saitama, 351-0198 (Japan); Bakule, Pavel [STFC, ISIS Facility, Rutherford Appleton Laboratory, Chilton, Oxfordshire OX11 0QX (United Kingdom); Yokoyama, Koji [Advanced Science Institute, RIKEN, 2-1 Hirosawa, Wako, Saitama, 351-0198 (Japan); Advanced Meson Science Laboratory, RIKEN Nishina Center, RIKEN, Wako, Saitama 351-0198 (Japan); Ishida, Katsuhiko; Iwasaki, Masahiko [Advanced Meson Science Laboratory, RIKEN Nishina Center, RIKEN, Wako, Saitama 351-0198 (Japan)

2011-09-15

We present a theoretical model combined with a computational study of a laser four-wave mixing process under optical discharge in which the non-steady-state four-wave amplitude equations are integrated with the kinetic equations of initial optical discharge and electron avalanche ionization in Kr-Ar gas. The model is validated by earlier experimental data showing strong inhibition of the generation of pulsed, tunable Lyman-{alpha} (Ly-{alpha}) radiation when using sum-difference frequency mixing of 212.6 nm and tunable infrared radiation (820-850 nm). The rigorous computational approach to the problem reveals the possibility and mechanism of strong auto-oscillations in sum-difference resonant Ly-{alpha} generation due to the combined effect of (i) 212.6-nm (2+1)-photon ionization producing initial electrons, followed by (ii) the electron avalanche dominated by 843-nm radiation, and (iii) the final breakdown of the phase matching condition. The model shows that the final efficiency of Ly-{alpha} radiation generation can achieve a value of {approx}5x10{sup -4} which is restricted by the total combined absorption of the fundamental and generated radiation.

Development of technologies for the waste management of I-129, Kr-85, C-14 and tritium in the Fed. Rep. of Germany

International Nuclear Information System (INIS)

Henrich, E.; Ebert, K.

1985-01-01

The main source of I-129, Kr-85, C-14 and tritium in Germany will be a 10-15 GWe LWR fuel reprocessing plant (FRP), expected to be in operation in the mid nineties. Guidelines for release regulations and development efforts are discussed. It has been recommended to limit the annual I-129 release to less than 0.2 curie. The uncontrolled release of Kr-85, C-14 or tritium via the stack resulting from the 15 GWe power will not exceed the limits derived from the German radiation protection ordinary. The development and hot demonstration of a Kr-85 control technology is recommended in view of the anticipated increasing use of nuclear power in the future. Commercial use of Xe and Kr may also contribute to the incentive for recovery. It would be simple to recover 14CO 2 once separated in the course of the I-129 or Kr-85 removal operations. Tritiated waste water once it has been separated in the course of processing, should not be deliberately released. Therefore, tritium control technology is being developed. General concepts and the present status of reference and back-up technologies as well as additional research in view of advanced processes are summarized

Adsorptive separation of xenon/krypton mixtures using a zirconium-based metal-organic framework with high hydrothermal and radioactive stabilities.

Science.gov (United States)

Lee, Seung-Joon; Yoon, Tae-Ung; Kim, Ah-Reum; Kim, Seo-Yul; Cho, Kyung-Ho; Hwang, Young Kyu; Yeon, Jei-Won; Bae, Youn-Sang

2016-12-15

The separation of xenon/krypton mixtures is important for both environmental and industrial purposes. The potential of three hydrothermally stable MOFs (MIL-100(Fe), MIL-101(Cr), and UiO-66(Zr)) for use in Xe/Kr separation has been experimentally investigated. From the observed single-component Xe and Kr isotherms, isosteric heat of adsorption (Q st o ), and IAST-predicted Xe/Kr selectivities, we observed that UiO-66(Zr) has the most potential as an adsorbent among the three candidate MOFs. We performed dynamic breakthrough experiments with an adsorption bed filled with UiO-66(Zr) to evaluate further the potential of UiO-66(Zr) for Xe/Kr separation under mixture flow conditions. Remarkably, the experimental breakthrough curves show that UiO-66(Zr) can efficiently separate the Xe/Kr mixture. Furthermore, UiO-66(Zr) maintains most of its Xe and Kr uptake capacity, as well as its crystallinity and internal surface area, even after exposure to gamma radiation (2kGy) for 7h and aging for 16 months under ambient conditions. This result indicates that UiO-66(Zr) can be considered to be a potential adsorbent for Xe/Kr mixtures under both ambient and radioactive conditions. Copyright © 2016 Elsevier B.V. All rights reserved.

Analysis of the gas outlets of the nuclear power plants relation between nuclides determined by gamma-spectrometry

International Nuclear Information System (INIS)

Mihalik, J.

2008-01-01

The National Radiation Protection Institute is interested in the long-time study of the noble gases outlets of nuclear power plants. One of the causes of monitoring the gas outlet is independent assessment of the influence nuclear power plant on the environment. Result of this analysis confirms the correlation between 88 Kr and 85m Kr in all technological compartments. Except the internal flue of the first production unit, the high correlation coefficient was determined between 88 Kr - 135 Xe and 85m Kr - 135 Xe. The analysis presented by this paper suggests that the highest correlation coefficient was always reached between 88 Kr and 85 mKr. Its values approached to 1. Similar results were confirmed between 85m Kr - 135 Xe and 88 Kr - 1 35 Xe. As far as the ratio of the specific activity concerns, we found certain congruence between 2006 and 2007. (authors)

Some experimental data on accommodation coefficients for the noble ions on metal surfaces

International Nuclear Information System (INIS)

Gusev, K.I.; Rijov, Y.A.; Shkarban, I.I.

1974-01-01

Methods and results of experimental measurements of energy accommodation for Ar + , Kr + , and Xe + ions with initial energy E 0 - 100-500eV bombarding Cu, Mo, Ag and other (including Mo - monocrystal) foil target are presented. The angular dependencies for the energy accommodation coefficient are obtained within the range of angle phi=0+70 deg (phi is the angle between the target surface normal and the beam direction)

Mound Facility activities in chemical and physical research: July-December 1979

International Nuclear Information System (INIS)

1980-01-01

Research is reported in the following fields: isotope separation (Ar, C, He, Kr, Ne, O, Xe), low-temperature research (H intermolecular potential functions, gas analysis in trennschaukel), separation chemistry ( 229 Th, 231 Pa, 230 Th, 234 U), separation research (liquid thermal diffusion, Ca isotope separation, molecular beam scattering, mutual diffusion of noble gas mixtures, lithium chemical exchange with cryptands), and calculations in plutonium chemistry (algorithms, valence in natural water)

Ionization and excitation of uranium in a hollow-cathode lamp

International Nuclear Information System (INIS)

Gagne, J.M.; Pianarosa, P.; Larin, G.; Saint-Dizier, J.P.; Bouchard, P.

1981-01-01

The influence of different carrier gases (Ne,Ar,Kr,Xe) their pressure, and discharge current on the excitation and ionization of uranium atoms in a vapor generator of hollow-cathode design has been investigated by monitoring emission line intensities. From our measurements of line intensities as a function of the carrier gas we obtain an indication of the role of Penning collisions on the excitation of radiative levels in U II

Data on collisions of hydrogen atoms and ions with atoms and molecules, (2)

International Nuclear Information System (INIS)

Nakai, Yohta; Kikuchi, Akira; Shirai, Toshizo; Sataka, Masao

1983-09-01

This report presents a compilation of the experimental data on cross sections for charge transfer of H, H + and H - with inert gases such as He, Ne, Ar, Kr and Xe. A survey has been made systematically of the literatures up to the end of 1982. The cross sections are given as a function of projectile energy in graphs and tables; a list of references is also attached. (author)

Removal or excitation of a 1s electron in Kr II and Kr III

International Nuclear Information System (INIS)

Pan Lin; Beck, Donald R; O'Malley, Steven M

2005-01-01

Relativistic configuration interaction calculations are done for Kr ions Kr II and Kr III. Transition energies and transition probabilities for 122 transitions between Kr II 4p 5 J = 1/2, 3/2→ 1s 4p 6 , 1s 4p 5 np (n = 5-8) J = 1/2, 3/2, 5/2; 437 transitions between Kr III 4p 4 J = 0, 1, 2→ 1s 4p 5 , 1s 4p 4 np (n = 5-8) J = 0, 1, 2, 3 have been calculated. These data have been used by experiment to reproduce the absorption spectrum of Kr II and Kr III and found to be in good agreement with their measurement. Also, the K-edge energy of neutral Kr, Kr II and Kr III has been calculated. The first is within 0.94 eV of an existing experiment, while the last two are calculated for the first time

Core drilling of drillholes ONK-KR13, ONK-KR14 and ONK-KR15 in ONKALO at Olkiluoto 2010 - 2011

International Nuclear Information System (INIS)

Toropainen, V.

2011-08-01

As a part of the confirming site investigations at Olkiluoto, Suomen Malmi Oy (Smoy) core drilled three drillholes ONK-KR13 (120.45 m), ONK-KR14 (75.27 m) and ONK-KR15 (79.96 m) in ONKALO, at Olkiluoto in June 2010 - March 2011. The diameter of the drillholes is 75.7 mm. Sodium fluorescein was used as a label agent in the drilling water, and the drillholes were washed and flushed after the drilling. The deviations of the drillholes were measured with the deviation measuring instruments EMS and Gyro. The core samples were logged according to Posiva's normal procedure for drillholes. The main rock types are veined and diatexitic gneisses and pegmatitic granite. The average natural fracture frequencies and RQDs of the core samples are 1.6 pcs/m and 97.0 % (ONK-KR13), 0.5 pcs/m and 99.3 % (ONK-KR14) and 1.6 pcs/m and 97.3 % (ONK-KR15). In drillhole ONK-KR13 one, and in drillhole ONK-KR15 three fractured zones were intersected. There was no fractured zones in drillhole ONK-KR14. Rock mechanical tests were performed to core samples. The average uniaxial compressive strength was 143.2 MPa, the average Young's Modulus was 57.3 GPa and the average Poisson's ratio was 0.25. (orig.)

Excimer lasers utilizing XeF and XeCl molecules

Energy Technology Data Exchange (ETDEWEB)

Bychkov, Yu I; Konovalov, I N; Losev, V F; Mesyats, G A; Ryzhov, V V; Tarasenko, V F; Fedorov, A I; Shemyakina, S B; Yastremskii, A G

1978-12-01

The results are given of an experimental and theoretical study of XeF (wavelength approx. 350 nm) and XeCl (wavelength approx. 308 nm) lasers excited by an electron beam, a discharge stabilized by an electron beam, and a rapid discharge. These lasers are representative of ones employing halides of noble gases, which are the most powerful sources of stimulated emission in the uv region. The XeCl laser is shown to have good emission characteristics with various methods of excitation. An analysis of the kinetics of processes in the plasma of lasers utilizing halides of noble gases showed that the main channel for the transfer of the beam's energy to the formation of excimer molecules is the ionic channel. An efficiency of about 2.6 percent and a specific radiant energy of 10 J.l/sup -1/ showed that XeCl* is one of the most effective excimer molecules.

Analytical formulae for total cross sections for electron scattering by atoms (N, O, F, Ne, P, S, Cl, Ar, As, Se, Br, Kr) between 0.5-10 keV

International Nuclear Information System (INIS)

Williart, A.

2001-01-01

Analytical formulae for total cross sections for electron scattering by atoms which are close to the noble gases (Ne, Ar and Kr), for electron energies ranging from 0.5 to 10 keV, have been obtained in this study. We have shown, previously, that molecular total cross sections, at these energies, depend on target polarizability and the number of target electrons. A similar behaviour has been supposed for total cross sections of some atoms (N, O, F, P, S, Cl, As, Se and Br). The obtained expression depends on atomic parameters and it is based in some correlation derived from noble gases. The applicability of the formula has been checked by comparison with available data for atomic oxygen. (orig.)

Analytical formulae for total cross sections for electron scattering by atoms (N, O, F, Ne, P, S, Cl, Ar, As, Se, Br, Kr) between 0.5-10 keV

Energy Technology Data Exchange (ETDEWEB)

Williart, A. [Univ. Nacional de Educacion a Distancia, Madrid (Spain). Dept. de Fisica de los Materiales; Garcia, G. [Centro de Investigaciones Energeticas, Medioambientales y Tecnologicas, Madrid (Spain)

2001-10-01

Analytical formulae for total cross sections for electron scattering by atoms which are close to the noble gases (Ne, Ar and Kr), for electron energies ranging from 0.5 to 10 keV, have been obtained in this study. We have shown, previously, that molecular total cross sections, at these energies, depend on target polarizability and the number of target electrons. A similar behaviour has been supposed for total cross sections of some atoms (N, O, F, P, S, Cl, As, Se and Br). The obtained expression depends on atomic parameters and it is based in some correlation derived from noble gases. The applicability of the formula has been checked by comparison with available data for atomic oxygen. (orig.)

Spectra of copperlike and zinclike xenon: Xe XXV and Xe XXVI

International Nuclear Information System (INIS)

Kaufman, V.; Sugar, J.; Rowan, W.L.

1988-01-01

The spectra of highly ionized xenon were generated in a tokamak plasma and photographed in the region 60--350 A with a 2.2-m grazing-incidence spectrograph. The 4s 2 --4s4p transitions of Zn-like xenon (Xe XXV) and all the 4l--4(l+1) transitions of Cu-like xenon (Xe XXVI) were measured with estimated uncertainties of +- 0.005 A. These measurements have been combined with previous wavelength measurements of Xe XXVI to determine energy levels. A value for the ionization energy of Xe 25+ of 6 912 400 +- 3000 cm -1 (857.0 +- 0.4 eV) was derived

Analysis results of PAVE sampling of groundwaters from open boreholes OL-KR2, OL-KR7, OL-KR13 and OL-KR15 at Olkiluoto, Eurajoki, in 2004

Energy Technology Data Exchange (ETDEWEB)

Hirvonen, H. [Teollisuuden Voima Oyj, Eurajoki (Finland); Hatanpaa, E. [lnsinoeoeritoimisto Paavo Ristola Oy, Hollola (Finland)

2005-12-15

Four groundwater samples were collected at Olkiluoto from open boreholes OL-KR2, OL-KR7, OL-KR13 and OL-KR15 with pressurised water sampling equipment (PAVE) between summer 2004 and the beginning of 2005. The aim of the ground water sampling was to get information for the basis of the monitoring program during ONKALO construction. Sampling sections were mainly chosen so that the results of the chemical analyses from earlier studies could be used for comparison. This study is a part of Olkiluoto's monitoring programme (OMO). This study presents the sampling methods and the results of the laboratory analyses of groundwater samples from the open boreholes OL-KR2/328.5-330.5 m, OL-KR7/275.5- 289.5 m, OL-KR13/362-365 m and OL-KR15/241-245 m. The analytical results of the groundwater samplings are compared to earlier analytical results. According to Davis and De Wiest's ( 1967) classification, all ground water samples represent the borehole water type Na-Cl. All ground water samples were brackish ( 1000 mg/L < TDS < 1 0000 mg/L) according to Davis's ( 1964) TDS classification. Comparison of analytical results of the samples to earlier results shows that some changes have occurred between samplings. Other parameters, with couple of particular exceptions, have a downward trend, but bicarbonate concentration has increased in all boreholes. Concentrations of main parameters have changed most in OL-KR7 and OL-KR13 waters. Gas analyses results have not changed significantly, but increased carbon dioxide concentration is noticed in gas analysis results also. (orig.)

The noble gas concentrations of the Martian meteorites GRV 99027 and paired NWA 7906/NWA 7907

Science.gov (United States)

Stephenson, Peter C.; Lin, Yangting; Leya, Ingo

2017-12-01

Here we present the isotopic concentrations of He, Ne, Ar, Kr, and Xe for the three Martian meteorites, namely Grove Mountains 99027 (GRV 99027), Northwest Africa 7906 (NWA 7906), and Northwest Africa 7907 (NWA 7907). The cosmic ray exposure (CRE) age for GRV 99027 of 5.7 ± 0.4 Ma (1σ) is consistent with CRE ages for other poikilitic basaltic shergottites and suggests that all were ejected in a single event 5.6 Ma ago. After correcting for an estimated variable sodium concentration, the CRE ages for NWA 7906 and NWA 7907 of 5.4 ± 0.4 and 4.9 ± 0.4 Ma (1σ), respectively, are in good agreement with the CRE age of 5 Ma favored by Cartwright et al. for NWA 7034. The data, therefore, support the conclusion that all three basaltic regolith breccias are paired. The 40Ar gas retention age for NWA 7907 of 1.3 Ga is in accord with Cartwright et al. For NWA 7906, we were unable to determine a 40Ar gas retention age. The 4He gas retention ages for NWA 7906 and 7907 are in the range of 200 Ma and are much shorter than the 40Ar gas retention age of NWA 7907, indicating that about 86-88% of the radiogenic 4He has been lost. The Kr and Xe isotopic concentrations in GRV 99027 are composed almost exclusively of Martian interior (MI) gases, while for NWA 7906 and NWA 7907, they indicate gases from the MI, elementally fractionated air, and possibly Martian atmosphere.

Resonant third harmonic generation of KrF laser in Ar gas

Energy Technology Data Exchange (ETDEWEB)

Rakowski, R. [Department of Experimental Physics, University of Szeged, 6720 Szeged, Dóm tér 9 (Hungary); Institute of Optoelectronics, Military University of Technology, Gen. S. Kaliskiego 2, 00–908 Warsaw (Poland); Barna, A. [Department of Experimental Physics, University of Szeged, 6720 Szeged, Dóm tér 9 (Hungary); Wigner Research Centre for Physics, Institute for Particle and Nuclear Physics, EURATOM Association HAS, 1121 Budapest, XII. Konkoly Thege Miklós út 29-33 (Hungary); Suta, T.; Földes, I. B. [Wigner Research Centre for Physics, Institute for Particle and Nuclear Physics, EURATOM Association HAS, 1121 Budapest, XII. Konkoly Thege Miklós út 29-33 (Hungary); Bohus, J.; Szatmári, S. [Department of Experimental Physics, University of Szeged, 6720 Szeged, Dóm tér 9 (Hungary); Mikołajczyk, J.; Bartnik, A.; Fiedorowicz, H. [Institute of Optoelectronics, Military University of Technology, Gen. S. Kaliskiego 2, 00–908 Warsaw (Poland); Verona, C. [Department of Mechanical Engineering, University “Tor Vergata”, Via Orazio Raimondo, 18–00173, Rome (Italy); Verona Rinati, G. [Department of Industrial Engineering, University “Tor Vergata”, Via Orazio Raimondo, 18–00173, Rome (Italy); Margarone, D. [Institute of Physics ASCR, v.v.i. (FZU), ELI-Beamlines Project, 182 21 Prague (Czech Republic); Nowak, T. [Institute of Nuclear Physics, PAN, E. Radzikowskiego 152, 31–342 Cracow (Poland); and others

2014-12-15

Investigations of emission of harmonics from argon gas jet irradiated by 700 fs, 5 mJ pulses from a KrF laser are presented. Harmonics conversion was optimized by varying the experimental geometry and the nozzle size. For the collection of the harmonic radiation silicon and solar-blind diamond semiconductor detectors equipped with charge preamplifiers were applied. The possibility of using a single-crystal CVD diamond detector for separate measurement of the 3rd harmonic in the presence of a strong pumping radiation was explored. Our experiments show that the earlier suggested 0.7% conversion efficiency can really be obtained, but only in the case when phase matching is optimized with an elongated gas target length corresponding to the length of coherence.

Media effects on the optical absorption spectra of silver clusters embedded in rara gas matrices

International Nuclear Information System (INIS)

Fedrigo, S.; Harbich, W.; Buttet, J.

1993-01-01

The optical absorption of small mass selected Ag n -clusters (n=7, 11, 15, 21) embedded in solid Ar, Kr and Xe has been measured. The absorption spectra show 1 to 3 major peaks between 3 and 4.5 eV, depending on the cluster size. Changing the matrix gas Ar→Kr→Xe induces a redshift which is comparable for all sizes studied and does not affect the main structure of the absorption spectra. We propose a scheme to estimate the gas phase value of the absorption energies which is in fair agreement with an estimation obtained by a simple model based on a Drude metal. (author). 10 refs, 2 figs

Geophysical borehole logging of the boreholes KR23 extension, KR29 and KR29b at Olkiluoto 2004

International Nuclear Information System (INIS)

Lahti, M.; Heikkinen, E.

2005-04-01

Suomen Malmi Oy conducted geophysical borehole logging of the boreholes KR23 extension, KR25b, KR29 and KR29b at the Olkiluoto site in Eurajoki during October 2004. The survey is a part of Posiva Oy's detailed investigation program for the final disposal of spent nuclear fuel. The assignment included the field work and processing of the acoustic data. The report describes the field operation, equipment as well as processing procedures and shows the obtained results and their quality in the appendices. The raw and processed data are delivered digitally in WellCAD and Excel format. (orig.)

Geophysical borehole logging of the boreholes KR23 extension, KR29 and KR29b at Olkiluoto 2004

Energy Technology Data Exchange (ETDEWEB)

Lahti, M. [Suomen Malmi Oy, Espoo (Finland); Heikkinen, E. [JP-Fintact Oy, Vantaa (Finland)

2005-04-15

Suomen Malmi Oy conducted geophysical borehole logging of the boreholes KR23 extension, KR25b, KR29 and KR29b at the Olkiluoto site in Eurajoki during October 2004. The survey is a part of Posiva Oy's detailed investigation program for the final disposal of spent nuclear fuel. The assignment included the field work and processing of the acoustic data. The report describes the field operation, equipment as well as processing procedures and shows the obtained results and their quality in the appendices. The raw and processed data are delivered digitally in WellCAD and Excel format. (orig.)

Laser surface modification of polyethersulfone films: effect of laser wavelength on biocompatibility

International Nuclear Information System (INIS)

Pazokian, H; Jelvani, S; Mollabashi, M; Barzin, J

2013-01-01

In this paper laser ablation of polyethersulfone (PES) films regarding to the change in biocompatibility of the surface is investigated at 3 different wavelengths of 193nm (ArF), 248 nm (KrF) and 308 nm (XeCl). The optimum laser fluence and number of pulses for the improvement of the surface biocompatibility is found by examination of the surface behavior in contact with platelets and fibroblasts cells at 3 wavelengths. These biological modifications are explained by alteration of the surface morphology and chemistry following irradiation. The results show that the KrF laser is the best choice for treatment of PES in biological applications.

Composition of lunar noble gases traped 2.5 AE and 3.5 AE ago

International Nuclear Information System (INIS)

Eugster, O.

1986-01-01

The times when the soils 74001 and 73261 were exposed on the lunar surface were determined by the U-235 - Xe-136 dating method. The isotopic composition of the trapped noble gases in these two soils is compared with that of the surface correlated noble gases in the young soils 12001 and in the present day solar wind. The surface correlated trapped gases are a mixture of implanted solar wind particles and retrapped lunar atmospheric gases. The observed changes are interpreted as a result of decreasing outgassing of radiogenic Ar-40 and perhaps He-4 and of fissiogenic Xe from the lunar crust. The old soils probably also contain surface correlated Kr-80 and Kr-82 produced by secondary cosmic ray neutron capture of adsorbed or retrapped bromine. To some extent the isotopic composition of the trapped gases in old lunar soil may also have been altered due to diffusion loss from material of low retentivity

Dewetting and nanopattern formation of thin Pt films on SiO2 induced by ion beam irradiation

International Nuclear Information System (INIS)

Hu, Xiaoyuan; Cahill, David G.; Averback, Robert S.

2001-01-01

Dewetting and nanopattern formation of 3 - 10 nm Pt thin films upon ion irradiation is studied using scanning electron microscopy (SEM). Lateral feature size and the fraction of exposed surface area are extracted from SEM images and analyzed as functions of ion dose. The dewetting phenomenon has little temperature dependence for 3 nm Pt films irradiated by 800 keV Kr + at temperatures ranging from 80 to 823 K. At 893 K, the films dewet without irradiation, and no pattern formation is observed even after irradiation. The thickness of the Pt films, in the range 3 - 10 nm, influences the pattern formation, with the lateral feature size increasing approximately linearly with film thickness. The effect of different ion species and energies on the dewetting process is also investigated using 800 keV Kr + and Ar + irradiation and 19.5keVHe + , Ar + , Kr + , and Xe + irradiation. The lateral feature size and exposed surface fraction scale with energy deposition density (J/cm2) for all conditions except 19.5keVXe + irradiation. [copyright] 2001 American Institute of Physics

Study on the Secondary Electron Yield γ of Insulator for PDP Cathode

Science.gov (United States)

Motoyama, Y.; Ushirozawa, M.; Matsuzaki, H.; Takano, Y.; Seki, M.

1999-10-01

The secondary electron yield γ of the Plasma Display Panel (PDP) cathode is an important research object because it is closely related to the discharge voltages etc. For metal cathodes, we made a comprehensive examination^1 of γ for all rare gas ions and metastables according to Hagstrum's theory.^2 For γ of MgO, which is the useful insulator cathode, Aboelfotoh et al.^3 calculated the values for Ne and Ar ions supposing a monochrome PDP. However, the values of γ for other rare gas ions and their metastables necessary for a full color PDP have not yet been calculated. These values are calculated in the present study after them. The results are as follows: For ions, He:0.481 and Kr,Xe:0, assuming that there are no impurity levels in MgO; For metastables, He:0.491, Ne:0.489, Ar:0.428, Kr:0.381, and Xe:0.214. These results should serve as useful parameters in discharge simulation for the PDP. ^1H. Matsuzaki: Trans. IEE Jpn., 111-A, 971 (1991). ^2H.D. Hagstrum: Phys. Rev., 96, 336 (1954), ibid., 122, 83 (1961). ^3M.O. Aboelfotoh and J.A. Lorenzen: J. Appl. Phys., 48, 4754 (1977).

Attenuation curves in concrete of neutrons from 100 to 400 MeV per nucleon He, C, Ne, Ar, Fe and Xe ions on various targets

Energy Technology Data Exchange (ETDEWEB)

Agosteo, S.; Nakamura, T.; Silari, M. E-mail: marco.silari@cern.ch; Zajacova, Z

2004-04-01

Data on transmission of neutrons in concrete generated by heavy ions of intermediate energies (of typically up to 1 GeV per nucleon) are of interest for shielding design of accelerators for use in both the research and in the medical field. The energy distributions of neutrons produced by ions of different species (from He to Xe) striking various targets at energies from 100 to 800 MeV per nucleon were recently measured by Kurosawa et al. in the angular range 0-90 deg. . These spectra were used as input data for Monte Carlo simulations to determine source terms and attenuation lengths in ordinary concrete. The present paper presents calculations for 100 MeV/u helium ions on a Cu target, 100 MeV/u carbon ions on C, Al, Cu and Pb, 100 MeV/u neon ions on Cu and Pb, 400 MeV/u carbon ions on C, Al, Cu and Pb, 400 MeV/u neon ions on Cu, 400 MeV/u Ar ions on Cu, 400 MeV/u Fe ions on Cu and 400 MeV/u Xe ions on Cu. The results include the contributions of all secondaries. Some of the resulting attenuation curves are best fitted by a double-exponential function rather than the usual single-exponential. The effect of various approximations introduced in the simulations is discussed. A comparison is made with shielding data for protons scaled with the ion mass number. A comparison is also made with a simple analytical model in use at GANIL.

Superconducting ECR ion source: From 24-28 GHz SECRAL to 45 GHz fourth generation ECR

Science.gov (United States)

Zhao, H. W.; Sun, L. T.; Guo, J. W.; Zhang, W. H.; Lu, W.; Wu, W.; Wu, B. M.; Sabbi, G.; Juchno, M.; Hafalia, A.; Ravaioli, E.; Xie, D. Z.

2018-05-01

The development of superconducting ECR source with higher magnetic fields and higher microwave frequency is the most straight forward path to achieve higher beam intensity and higher charge state performance. SECRAL, a superconducting third generation ECR ion source, is designed for 24-28 GHz microwave frequency operation with an innovative magnet configuration of sextupole coils located outside the three solenoids. SECRAL at 24 GHz has already produced a number of record beam intensities, such as 40Ar12+ 1.4 emA, 129Xe26+ 1.1 emA, 129Xe30+ 0.36 emA, and 209Bi31+ 0.68 emA. SECRAL-II, an upgraded version of SECRAL, was built successfully in less than 3 years and has recently been commissioned at full power of a 28 GHz gyrotron and three-frequency heating (28 + 45 + 18 GHz). New record beam intensities for highly charged ion production have been achieved, such as 620 eμA 40Ar16+, 15 eμA 40Ar18+, 146 eμA 86Kr28+, 0.5 eμA 86Kr33+, 53 eμA 129Xe38+, and 17 eμA 129Xe42+. Recent beam test results at SECRAL and SECRAL II have demonstrated that the production of more intense highly charged heavy ion beams needs higher microwave power and higher frequency, as the scaling law predicted. A 45 GHz superconducting ECR ion source FECR (a first fourth generation ECR ion source) is being built at IMP. FECR will be the world's first Nb3Sn superconducting-magnet-based ECR ion source with 6.5 T axial mirror field, 3.5 T sextupole field on the plasma chamber inner wall, and 20 kW at a 45 GHz microwave coupling system. This paper will focus on SECRAL performance studies at 24-28 GHz and technical design of 45 GHz FECR, which demonstrates a technical path for highly charged ion beam production from 24 to 28 GHz SECRAL to 45 GHz FECR.

Stopping power measurements for 4-5MeV/nucleon 16O, 40Ar, 63Cu and 84Kr in C, Al, Ni, Ag and Au

International Nuclear Information System (INIS)

Bimbot, R.; Della Negra, S.; Gardes, D.; Gauvin, H.; Fleury, A.; Hubert, F.

1977-01-01

The stopping powers for (4 and 5 MeV/nucleon) 16 O, 40 Ar, 63 Cu and 84 Kr have been measured in C, Al, Ni, Ag and Au media. The experimental technique consists in measuring accurately the energy of protons elastically scattered at zero degree by the incident and degraded beams. The experimental results have been compared with stopping powers calculated in different ways. Discrepancies as large as 30% have been observed for the heaviest ions in light media (C, Al), the experimental values being higher than the calculated ones. Moreover, this comparison indicates that, from these calculations, no agreement can be obtained in the whole range of incident ions and stopping media. On the contrary, a quantitative agreement was obtained by a new calculation mode which takes into account the variation of the moving ion effective charge with the atomic number of the stopping medium

A 1-kJ KrF laser system for laser fusion research

International Nuclear Information System (INIS)

Owadano, Y.; Okuda, I.; Tanimoto, M.; Matsumoto, Y.; Yaoita, A.; Komeiji, S.; Yano, M.

1987-01-01

Ultraviolet laser light has several advantages in coupling with a laser fusion target, and the KrF laser is considered to be a promising candidate for the driver because of its short wavelength, high overall efficiency, and scalability to a megajoule class system. The Electrotechnical Laboratory is developing a 1-kJ class KrF laser system to perform target-shooting experiments in the 10/sup 13/-10/sup 15/-W/cm/sup 2/, 10-20-ns range and to investigate the possibility of a compact laser fusion driver which operates at a high pumping density and high laser power density. Based on the pulsed-power technology used in Amp2 and the characteristics of the Kr-rich mixture measured, Amp3 was designed to operate at high optical power density with a Kr-rich mixture. Amp3 has four PFLs charged by a single 40-kJ Marx generator and four e-beam diodes (550 kV, 4 Ω) arranged cylindrically around the laser cell. The active volume is 660 cm/sup 2/ (29 cm in diameter) X 1 m, and 2-atm Kr is pumped at a density of 1.9 MW/cm/sup 3/. Output energy of 1 kJ is expected at an intrinsic efficiency of 8.3% and overall efficiency of 2.5%. Output energy fluence is 1.5 J/cm/sup 2/ (15 MW/cm/sup 2/) on average, which is lower than the damage threshold of our fully reflecting AR coatings (>3 J/cm/sup 2/)

Powerful highly efficient KrF lamps excited by surface and barrier discharges

International Nuclear Information System (INIS)

Borisov, V M; Vodchits, V A; El'tsov, A V; Khristoforov, O B

1998-01-01

An investigation was made of the characteristics of KrF lamps with different types of excitation by surface and barrier discharges in which the dielectric material was sapphire. The conditions were determined for the attainment of an extremely high yield of the KrF* fluorescence with the internal efficiency η in ∼30 % and 22% for pulsed surface and barrier discharges, respectively. A homogeneous surface discharge was maintained without gas circulation when the pulse repetition rate was 5 x 10 4 Hz. Quasicontinuous excitation of a surface discharge at near-atmospheric pressure made it possible to reach a KrF* fluorescence power density of about 80 W cm -3 , which was close to the limit set by the kinetics of the gaseous medium. Under prolonged excitation conditions the intensity of the UV output radiation was limited by the permissible heating of the gas to a temperature above which the operating life of the gaseous mixture containing fluorine fell steeply. This was the reason for the advantage of surface over barrier discharges: the former were characterised by a high thermal conductivity of a thin (∼0.2 mm) plasma layer on the surface of the cooled dielectric, which made it possible to construct powerful highly efficient KrF and ArF lamps emitting UV radiation of up to 1 W cm -2 intensity. (laser system components)

Data on collisions of helium atoms and ions with atoms and molecules, (2)

International Nuclear Information System (INIS)

Nakai, Yohta; Shirai, Toshizo; Sataka, Masao; Kikuchi, Akira.

1984-04-01

This report presents a compilation of the experimental data on cross sections for charge transfer of He 2+ , He + , He and He - with inert gases such as He, Ne, Ar, Kr and Xe. A survey has been made systematically of the literatures up to the end of 1983. The cross sections are given as a function of projectile energy in graphs and tables, and a list of references is also attached. (author)

Experimental and calculated calibration of ionization chambers with air circulation

CERN Document Server

Peetermans, A

1972-01-01

The reports describes the method followed in order to calibrate the different ionization chambers with air circulation, used by the 'Health Physics Group'. The calculations agree more precisely with isotopes cited previously (/sup 11/C, /sup 13/N, /sup 15/O, /sup 41 /Ar, /sup 14/O, /sup 38/Cl) as well as for /sup 85/Kr, /sup 133/Xe, /sup 14/C and tritium which are used for the experimental standardisation of different chambers.

Double-electron excitation above Xe K-edge

International Nuclear Information System (INIS)

Ito, Y.; Tochio, T.; Vlaicu, A.M.; Mutaguchi, K.; OhHashi, H.; Shigeoka, N.; Nakata, Y.; Akahama, Y.; Uruga, T.; Emura, Sh.

2000-01-01

When X-rays fall on any substance, whether solid, liquid, or gaseous, a photoabsorption occurs. Photoabsorption in atoms has been generally treated as a single-electron excitation process. However, the existence of the multi-electron excitation process, where the removal of a core electron by photoabsorption causes excitation of additional electrons in the same atoms, has been known in x-ray absorption spectra for a long time. In x-ray absorption spectra, experimental investigations of the shake processes in inner-shell ionization phenomena have been performed by detecting discontinuities. The shake effect which is a consequence of rearrangement of the atomic electrons, occurs in association with inner-shell excitation and ionization phenomena in x-ray absorption. The shake process has been studied extensively in various gases, because it is usually considered that the measurement of the multi-electron excitation is only possible for monatomic gases or vapors. The x-ray absorption spectra in Kr gas were measured by Ito et al. in order to observe precisely x-ray absorption spectra and to investigate the multi-electron excitation cross sections in Kr as a function of photon energy using synchrotron radiation. However, no suitable measured K x-ray absorption spectra was available to elucidate the shake processes. In the present work, the photoabsorption cross sections in Xe have been precisely measured in order to determine the features on the shake processes resulting from multiple electron excitations as a function of photon energy. Double-electron transitions of [1s4d], [1s4p], [1s4s], and [1s3d] are first detected. (author)

Hyperfine spectra of the radioactive isotopes 81Kr and 85Kr

International Nuclear Information System (INIS)

Cannon, B.D.

1993-01-01

Isotope shifts and hyperfine constants are reported for the radioactive isotopes 81 Kr and 85 Kr and the stable isotope 83 Kr. The previously unreported nuclear moments of 81 Kr were determined to be μ I =-0.909(4) nuclear magneton and Q=+0.630(13) b from the hyperfine constants. This work increases the number of transitions for which 85 Kr hyperfine constants and isotope shifts have been measured from 1 to 4. The hyperfine anomaly for krypton reported in the previous measurement of 85 Kr hyperfine constants [H. Gerhardt et al., Hyperfine Interact. 9, 175 (1981)] is not supported by this work. The isotope shifts and hyperfine constants of 83 Kr measured in this work are in excellent agreement with previous work. Saturation spectroscopy was used to study transitions from krypton's metastable 1s 5 state to the 2p 9 , 2p 7 , and 2p 6 states. In saturation spectra, different line shapes were observed for the even- and odd-mass krypton isotopes. This even- versus odd-line-mass shape difference can be explained using the large cross section that has been reported for collisional transfer of the 1s 5 state excitation between krypton atoms. Two-color two-photon laser-induced fluorescence was used to measure the hyperfine spectra of the 1s 5- 4d 4 ' transition using the 2p 9 state as the intermediate state. This technique proved to be more sensitive than saturation spectroscopy

Calculation of electron transport in Ar/N2 and He/Kr gas mixtures emdash implications for validity of the Blanc close-quote s law method

International Nuclear Information System (INIS)

Wang, Y.; Van Brunt, R.J.

1997-01-01

The electron drift velocities and corresponding mean energies have been calculated numerically using an approximate two-term solution of the Boltzmann transport equation for Ar/N 2 gas mixtures at electric field-to-gas density ratios (E/N) below 2.0x10 -20 Vm 2 (20 Td) and for He/Kr mixtures at E/N below 5.0x10 -21 Vm 2 (5.0 Td). The results are compared with predictions obtained from a method proposed by Chiflikian based on an open-quotes analog of Blanc close-quote s lawclose quotes [Phys. Plasmas 2, 3902 (1995)]. Large differences are found between the results derived from the Blanc close-quote s law method and those found here from solutions of the transport equation that indicate serious errors and limitations associated with use of the Blanc close-quote s law method to compute drift velocities in gas mixtures. copyright 1997 American Institute of Physics

Energy levels and radiative rates for transitions in B-like to F-like Xe ions (Xe L-XLVI)

International Nuclear Information System (INIS)

Aggarwal, K.M.; Keenan, F.P.; Lawson, K.D.

2010-01-01

Energy levels, radiative rates, oscillator strengths, line strengths, and lifetimes have been calculated for transitions in B-like to F-like Xe ions, Xe L-XLVI. For the calculations, a fully relativistic GRASP code has been adopted, and results are reported for all electric dipole, electric quadrupole, magnetic dipole, and magnetic quadrupole transitions among the lowest 125, 236, 272, 226, and 113 levels of Xe L, Xe XLIX, Xe XLVIII, Xe XLVII, and Xe XLVI, respectively, belonging to the n ≤ 3 configurations.

A Kinetics Model for KrF Laser Amplifiers

Science.gov (United States)

Giuliani, J. L.; Kepple, P.; Lehmberg, R.; Obenschain, S. P.; Petrov, G.

1999-11-01

A computer kinetics code has been developed to model the temporal and spatial behavior of an e-beam pumped KrF laser amplifier. The deposition of the primary beam electrons is assumed to be spatially uniform and the energy distribution function of the nascent electron population is calculated to be near Maxwellian below 10 eV. For an initial Kr/Ar/F2 composition, the code calculates the densities of 24 species subject to over 100 reactions with 1-D spatial resolution (typically 16 zones) along the longitudinal lasing axis. Enthalpy accounting for each process is performed to partition the energy into internal, thermal, and radiative components. The electron as well as the heavy particle temperatures are followed for energy conservation and excitation rates. Transport of the lasing photons is performed along the axis on a dense subgrid using the method of characteristics. Amplified spontaneous emission is calculated using a discrete ordinates approach and includes contributions to the local intensity from the whole amplifier volume. Specular reflection off side walls and the rear mirror are included. Results of the model will be compared with data from the NRL NIKE laser and other published results.

Optical imaging of the boreholes KR37, KR37B and KR38 at Olkiluoto 2005

International Nuclear Information System (INIS)

Majapuro, J.

2006-02-01

Suomen Malmi Oy conducted optical imaging surveys of the boreholes KR37, KR37B and KR38 at the Olkiluoto site in Eurajoki during September 2005. The survey is a part of Posiva Oy's detailed investigation program for the final disposal of spent nuclear fuel. The assignment included the field work and preliminary processing of the images. The report describes the field operation, equipment as well as processing procedures and shows the obtained results and their quality through example images. The raw and processed data are delivered digitally in WellCAD format. The images are also attached to the appendix CD of this report in Adobe Acrobat PDF-format. (orig.)

Production of noble gas isotopes by proton-induced reactions on bismuth

International Nuclear Information System (INIS)

Leya, I.; David, J.-C.; Leray, S.; Wieler, R.; Michel, R.

2008-01-01

We measured integral thin target cross sections for the proton-induced production of He-, Ne-, Ar-, Kr- and Xe-isotopes from bismuth (Bi) from the respective reaction thresholds up to 2.6 GeV. Here we present 275 cross sections for 23 nuclear reactions. The production of noble gas isotopes from Bi is of special importance for design studies of accelerator driven systems (EA/ADS) and nuclear spallation sources. For experiments with proton energies above 200 MeV the mini-stack approach was used instead of the stacked-foil technique in order to minimise the influences of secondary particles on the residual nuclide production. Comparing the cross sections for Bi to the data published recently for Pb indicates that for 4 He the cross sections for Bi below 200 MeV are up to a factor of 2-3 higher than the Pb data, which can be explained by the production of α-decaying Po-isotopes from Bi but not from Pb. Some of the cross sections for the production of 21 Ne from Bi are affected by recoil effects from neighboured Al-foils, which compromises a study of a possible lowering of the effective Coulomb-barrier. The differences in the excitation functions between Pb and Bi for Kr- and Xe-isotopes can be explained by energy-dependent higher fission cross sections for Bi compared to Pb. The experimental data are compared to results from the theoretical nuclear model codes INCL4/ABLA and TALYS. The INCL4/ABLA system describes the cross sections for the production of 4 He-, Kr- and Xe-isotopes reasonably well, i.e. mostly within a factor of a few. In contrast, the model completely fails describing 21 Ne, 22 Ne, 36 Ar and 38 Ar, which are produced via spallation and/or multifragmentation. The TALYS code is only able to accurately predict reaction thresholds. The absolute values are either significantly over- or underestimated. Consequently, the comparison of measured and modelled thin target cross sections clearly indicates that experimental data are still needed because the

Transferability and accuracy by combining dispersionless density functional and incremental post-Hartree-Fock theories: Noble gases adsorption on coronene/graphene/graphite surfaces

Energy Technology Data Exchange (ETDEWEB)

Lara-Castells, María Pilar de, E-mail: Pilar.deLara.Castells@csic.es; Bartolomei, Massimiliano [Instituto de Física Fundamental (C.S.I.C.), Serrano 123, E-28006 Madrid (Spain); Mitrushchenkov, Alexander O. [Laboratoire Modélisation et Simulation Multi Echelle, Université Paris-Est, MSME UMR 8208 CNRS, 5 bd Descartes, 77454 Marne-la-Vallée (France); Stoll, Hermann [Institut für Theoretische Chemie, Universität Stuttgart, D-70550 Stuttgart (Germany)

2015-11-21

The accuracy and transferability of the electronic structure approach combining dispersionless density functional theory (DFT) [K. Pernal et al., Phys. Rev. Lett. 103, 263201 (2009)] with the method of increments [H. Stoll, J. Chem. Phys. 97, 8449 (1992)], are validated for the interaction between the noble-gas Ne, Ar, Kr, and Xe atoms and coronene/graphene/graphite surfaces. This approach uses the method of increments for surface cluster models to extract intermonomer dispersion-like (2- and 3-body) correlation terms at coupled cluster singles and doubles and perturbative triples level, while periodic dispersionless density functionals calculations are performed to estimate the sum of Hartree-Fock and intramonomer correlation contributions. Dispersion energy contributions are also obtained using DFT-based symmetry-adapted perturbation theory [SAPT(DFT)]. An analysis of the structure of the X/surface (X = Ne, Ar, Kr, and Xe) interaction energies shows the excellent transferability properties of the leading intermonomer correlation contributions across the sequence of noble-gas atoms, which are also discussed using the Drude oscillator model. We further compare these results with van der Waals-(vdW)-corrected DFT-based approaches. As a test of accuracy, the energies of the low-lying nuclear bound states supported by the laterally averaged X/graphite potentials (X = {sup 3}He, {sup 4}He, Ne, Ar, Kr, and Xe) are calculated and compared with the best estimations from experimental measurements and an atom-bond potential model using the ab initio-assisted fine-tuning of semiempirical parameters. The bound-state energies determined differ by less than 6–7 meV (6%) from the atom-bond potential model. The crucial importance of including incremental 3-body dispersion-type terms is clearly demonstrated, showing that the SAPT(DFT) approach effectively account for these terms. With the deviations from the best experimental-based estimations smaller than 2.3 meV (1.9%), the

Fluorescence emissions from mixtures of Hg with the noble gases

International Nuclear Information System (INIS)

Woodworth, J.R.

1977-01-01

Fluorescence emissions from mixtures of Hg with high pressure Xe, Kr, and Ar (approx.1 torr Hg, 10 3 --10 4 torr noble gas) have been studied using a short-pulse relativistic electron beam as an excitation source. Hg--noble gas molecular bands were observed on the red sides of the Hg lines (1849 and 2537 A) as well as on the red sides of the Hg visible lines (7 3 S 1 →6 3 P 0 , 1 , 2 ). Temporal histories and production efficiencies of the molecular emissions were determined and a model was formulated for the time histories of the HgXe 2600 A bands. Possible applications to high power laser systems are discussed

Geophysical borehole logging of the boreholes KR37, KR37B and KR38, at Olkiluoto 2005

International Nuclear Information System (INIS)

Majapuro, J.

2006-03-01

Suomen Malmi Oy conducted geophysical borehole logging of the boreholes KR37, KR37b and KR38 at the Olkiluoto site in Eurajoki during September and October 2005. The survey is a part of Posiva Oy's detailed investigation program for the final disposal of spent nuclear fuel. The assignment included the field work and processing of the acoustic data. The report describes the field operation, equipment as well as processing procedures and shows the obtained results and their quality in the appendices. The raw and processed data are delivered digitally in WellCAD and Excel format. (orig.)

Long-range dispersion interactions. II. Alkali-metal and rare-gas atoms

International Nuclear Information System (INIS)

Mitroy, J.; Zhang, J.-Y.

2007-01-01

The dispersion coefficients for the van der Waals interactions between the rare gases Ne, Ar, Kr, and Xe and the low-lying states of Li, Na, K, and Rb are estimated using a combination of ab initio and semiempirical methods. The rare-gas oscillator strength distributions for the quadrupole and octupole transitions were derived by using high-quality calculations of rare-gas polarizabilities and dispersion coefficients to tune Hartree-Fock single-particle energies and expectation values

Measurements of the diffusion and reflection coefficients of Cd(1S0) in noble gases

International Nuclear Information System (INIS)

Rudecki, P.; Domyslawska, J.

2003-01-01

A new method of simultaneous determining of the diffusion coefficient and the reflection coefficient of atoms from the reservoir walls is presented. The diffusion coefficient of cadmium atoms in the ground state in buffer noble gas atoms such as Ne, Ar, Kr and Xe and reflection coefficient of Cd atoms from the quartz cell wall in the temperature range 350-550 K were determined. Experimental values diffusion coefficient are compared with theoretical ones calculated from a available potentials. (author)

Spectroscopie de diffusion de la lumière dans les mélanges de gaz atomiques

OpenAIRE

Dixneuf , Sophie

2006-01-01

This thesis is a contribution to the study of the interaction-induced polarizabilities by rare gases, in both the coordinate and the frequency representation. For the first time, collision-induced Raman spectra by atomic gaseous mixtures were recorded, computed quantum mechanically, and interpreted. More specifically, anisotropic and isotropic Stokes spectral wings by room-temperature Ne-Ar were investigated up to 300 cm-1 , whereas the anisotropic wing of the Kr-Xe was explored up to 135 cm-...

Procedure for the preparation of catalysts for application in catalytic gas phase reactions

International Nuclear Information System (INIS)

1976-01-01

The invention describes the preparation of catalysts to be used in catalytic reactions in the gaseous phase. The catalytic material is disposed at the surface of a ceramic or carbon substrate (av. particle size 0.1 μ - 0.5 cm, surface area smaller than 20 m 2 /g) by bombardment of the catalytic material (Pt, Rh, Pd, Ru, Os, Ir) with energetic ions (Ne, Ar, Kr, Xe) in the vicinity of the substrate in medium vacuum

Photoemission from excited states in rare gas solids by combining synchrotronradiation with a laser

International Nuclear Information System (INIS)

Bernstorff, S.

1984-09-01

A new spectroscopic method has been developed to study excited states in rare gas solids: Excitons and conductionband-states are populated by synchrotron radiation (photon energy hw SR =5 - 30 eV). Subsequently electrons from these bound or conduction band-states are excited above the vacuum level of the solid by a pulsed dye laser (hw L =1.9 - 3.7 eV). This experimental technique was applied to solid Xe, Kr, Ar and Ne. (orig./GSCH)

Recharge Rates to Deep Aquifer Layers Estimated with {sup 39}Ar, {sup 85}Kr and {sup 14}C Data: A Case Study in Odense (Denmark)

Energy Technology Data Exchange (ETDEWEB)

Purtschert, R. [Climate and Environmental Physics, University of Bern (Switzerland); Bjerre, T. K.; Linderberg, J. [Odense Water, Odense (Denmark); Hinsby, K. [Geological Survey of Denmark and Greenland (GEUS), Copenhagen (Denmark)

2013-07-15

The increasing pressure on groundwater resources due to overexploitation, contamination and also due to the effects of climate change leads to an increasing need and interest to investigate the recharge and flow dynamics of pre-modern groundwater (>50 a old). Knowledge about turnover times and groundwater age is crucial e.g. in vulnerability assessment studies as shallow and young groundwater is more susceptible to environmental changes than deeper and generally older groundwater. The presence and age of young water can be determined by a series of transient tracers (e.g. {sup 3}H/{sup 3}He, CFC's, SF{sub 6}, etc). However, with the need to exploit deeper unpolluted resources a tracer on timescales of hundreds of years is required. {sup 39}Ar (T{sub 1/2}: 269 a), {sup 85}Kr (T{sub 1/2}: 10.8 a) and {sup 14}C (T{sub 1/2}: 5730 a) results from 35 wells around the city of Odense (Denmark) are presented. The determined age spectra range from a few years to several hundreds of years. Based on the space-depth distribution of age gradients, renewal/recharge rates to the deep aquifer layers have been estimated. The comparison of {sup 39}Ar and {sup 14}C activities reveals a remarkably good correlation but with a distinct difference in age scale suggesting mixing due to broad age distributions and activity shifts due to rock-water interaction. (author)

K-edge x-ray-absorption spectroscopy of laser-generated Kr+ and Kr2+

International Nuclear Information System (INIS)

Southworth, S. H.; Arms, D. A.; Dufresne, E. M.; Dunford, R. W.; Ederer, D. L.; Hoehr, C.; Kanter, E. P.; Kraessig, B.; Landahl, E. C.; Peterson, E. R.; Rudati, J.; Santra, R.; Walko, D. A.; Young, L.

2007-01-01

Tunable, polarized, microfocused x-ray pulses were used to record x-ray absorption spectra across the K edges of Kr + and Kr 2+ produced by laser ionization of Kr. Prominent 1s→4p and 5p excitations are observed below the 1s ionization thresholds in accord with calculated transition energies and probabilities. Due to alignment of 4p hole states in the laser-ionization process, the Kr + 1s→4p cross section varies with respect to the angle between the laser and x-ray polarization vectors. This effect is used to determine the Kr + 4p 3/2 and 4p 1/2 quantum state populations, and these are compared with results of an adiabatic strong-field ionization theory that includes spin-orbit coupling

Rare gas constraints on the history of Boulder 1, Station 2, Apollo 17

International Nuclear Information System (INIS)

Leich, D.A.; Kahl, S.B.; Kirschbaum, A.R.; Niemeyer, S.; Phinney, D.

1975-01-01

Rare gas isotopic analyses have been performed on both pile-irradiated and unirradiated samples from Boulder 1, Station 2. Two samples from rock 72255, the Civet Cat clast and a sample of adjacent breccia, have concordant 40 Ar- 39 Ar ages of 3.99 +- 0.03 b.y. and 4.01 +- 0.03 b.y., respectively. Several samples from rock 72275 have complex thermal release patterns with no datable features, but an intermediate temperature plateau from the dark rim material of the Marble Cake clast yields an age of 3.99 +- 0.03 b.y., indistinguishable from the age of rock 72255. We regard these ages as upper limits on the time of the Serenitatis basin-forming event. The absence of fossil solar-wind trapped gases in the breccia samples implies that a prior existence for the boulder as near-surface regolith material can be regarded as extremely unlikely. Instead, the small trapped rare-gas components have isotopic and elemental compositions diagnostic of the terrestrial-type trapped component which has previously been identified in several Apollo 16 breccias and in rock 14321. Excess fission Xe is found in all Boulder 1 samples in approximately 1:1 proportions with Xe from spontaneous fission of 238 U. This excess fission Xe is attributed to spontaneous fission of 244 Pu in situ. Cosmic-ray exposure ages for samples from rocks 72215 and 72255 are concordant with mean 81 Kr-Kr exposure ages of 41.4 +- 1.4 m.y. and 44.1 +- 3.3 m.y., respectively. However, a distinctly different 81 Kr-Kr exposure age of 52.5 +- 1.4 m.y. is obtained for samples from rock 72275. A two-stage exposure model is developed to account for this discordance and for the remaining cosmogenic rare-gas data. The first stage was initiated at least 55 m.y. ago, probably as a result of the excavation of the boulder source-crop. A discrete change in shielding depths approx. 35 m.y. ago probably corresponds to the dislodgement of Boulder 1 from the South Massif and emplacement in its present position

Geophysical logging and imaging of characterisation drillholes ONK-KR13, ONK-KR14 and ONK-KR15

International Nuclear Information System (INIS)

Tarvainen, A.-M.

2011-08-01

Suomen Malmi Oy conducted geophysical drillhole logging as well as optical and acoustic imaging of drillholes ONK-KR13, ONK-KR14 and ONK-KR15 at ONKALO in June-July 2010 and in March 2011. The survey is a part of Posiva Oy's detailed investigation program for the final disposal of spent nuclear fuel. The assignment included the field work and data processing. The report describes field operation, equipment as well as processing procedures and shows the obtained results and an analysis of their quality in the appendices. The raw and processed data are delivered digitally in WellCAD, PDF and Excel format. (orig.)

Growth responses of Neurospora crassa to increased partial pressures of the noble gases and nitrogen.

Science.gov (United States)

Buchheit, R G; Schreiner, H R; Doebbler, G F

1966-02-01

Buchheit, R. G. (Union Carbide Corp., Tonawanda, N.Y.), H. R. Schreiner, and G. F. Doebbler. Growth responses of Neurospora crassa to increased partial pressures of the noble gases and nitrogen. J. Bacteriol. 91:622-627. 1966.-Growth rate of the fungus Neurospora crassa depends in part on the nature of metabolically "inert gas" present in its environment. At high partial pressures, the noble gas elements (helium, neon, argon, krypton, and xenon) inhibit growth in the order: Xe > Kr> Ar > Ne > He. Nitrogen (N(2)) closely resembles He in inhibitory effectiveness. Partial pressures required for 50% inhibition of growth were: Xe (0.8 atm), Kr (1.6 atm), Ar (3.8 atm), Ne (35 atm), and He ( approximately 300 atm). With respect to inhibition of growth, the noble gases and N(2) differ qualitatively and quantitatively from the order of effectiveness found with other biological effects, i.e., narcosis, inhibition of insect development, depression of O(2)-dependent radiation sensitivity, and effects on tissue-slice glycolysis and respiration. Partial pressures giving 50% inhibition of N. crassa growth parallel various physical properties (i.e., solubilities, solubility ratios, etc.) of the noble gases. Linear correlation of 50% inhibition pressures to the polarizability and of the logarithm of pressure to the first and second ionization potentials suggests the involvement of weak intermolecular interactions or charge-transfer in the biological activity of the noble gases.

Charge changing processes in the formation of fast H0 atoms

International Nuclear Information System (INIS)

Anderson, C.J.

1979-01-01

Measurements are reported of the charge changing cross sections sigma- 0 , sigma-/sub +/, sigma/sub g+/ sigma/sub g-/ for H - ions incident on Ne, Ar, Kr, Xe, Li, Na, K, Rb and Cs targets in the energy range 25 to 200 keV. The maximum neutral fractions, F 0 /sup max/, for H - ions incident on H 2 , D 2 , CO 2 , H 2 O, C 4 H 10 , C 5 H 12 , CF 4 , CHF 3 , CClF 3 , CBrF 3 , acetone, 2-propanol and natural gas have been measured in the energy range 30 to 200 keV. The largest neutral fraction for 100 keV H - is 0.631 produced in a Li vapor target. The equilibrium fractions F/sub -//sup infinity/, F 0 /sup infinity/ and F/sub +//sup infinity/ for H - ions incident on H 2 , He, Ne, Ar, Kr, Xe, Li, Na, K, Rb and Cs have been measured in the energy range 30 to 200 keV. Also measured are the cross sections sigma/sub +0/ and sigma/sub +-/ and the equilibrium fractions F/sub -//sup infinity/, F 0 /sup infinity/ and F/sub +//sup infinity/ for H + incident on a Na target in the energy range 1-25 keV. The largest value of F/sub -//sup infinity/ is 0.101 for H + incident at 2 keV

Noble gas encapsulation into carbon nanotubes: Predictions from analytical model and DFT studies

Energy Technology Data Exchange (ETDEWEB)

Balasubramani, Sree Ganesh; Singh, Devendra; Swathi, R. S., E-mail: swathi@iisertvm.ac.in [School of Chemistry, Indian Institute of Science Education and Research Thiruvananthapuram (IISER-TVM), Kerala 695016 (India)

2014-11-14

The energetics for the interaction of the noble gas atoms with the carbon nanotubes (CNTs) are investigated using an analytical model and density functional theory calculations. Encapsulation of the noble gas atoms, He, Ne, Ar, Kr, and Xe into CNTs of various chiralities is studied in detail using an analytical model, developed earlier by Hill and co-workers. The constrained motion of the noble gas atoms along the axes of the CNTs as well as the off-axis motion are discussed. Analyses of the forces, interaction energies, acceptance and suction energies for the encapsulation enable us to predict the optimal CNTs that can encapsulate each of the noble gas atoms. We find that CNTs of radii 2.98 − 4.20 Å (chiral indices, (5,4), (6,4), (9,1), (6,6), and (9,3)) can efficiently encapsulate the He, Ne, Ar, Kr, and Xe atoms, respectively. Endohedral adsorption of all the noble gas atoms is preferred over exohedral adsorption on various CNTs. The results obtained using the analytical model are subsequently compared with the calculations performed with the dispersion-including density functional theory at the M06 − 2X level using a triple-zeta basis set and good qualitative agreement is found. The analytical model is however found to be computationally cheap as the equations can be numerically programmed and the results obtained in comparatively very less time.

Capacitive discharge exciplex lamps

Energy Technology Data Exchange (ETDEWEB)

Sosnin, E A; Erofeev, M V; Tarasenko, V F [High Current Electronics Institute, 2/3, Akademichesky Ave., Tomsk 634055 (Russian Federation)

2005-09-07

Simple-geometry exciplex lamps of a novel type excited by a capacitive discharge (CD-excilamps) have been investigated. An efficient radiation has been obtained on KrBr*, KrCl*, XeBr*, XeCl* molecules and I* atom. The highest values of efficiency of various working molecules are approximately 10-18%. The lifetime of the operating gas mixture in KrCl*, XeCl*, I* and XeBr* exciplex lamps excited by a CD is above 1000 h. Owing to the above-mentioned characteristics, the exciplex lamps excited by a CD are supposed to be very promising for various applications.

Capacitive discharge exciplex lamps

International Nuclear Information System (INIS)

Sosnin, E A; Erofeev, M V; Tarasenko, V F

2005-01-01

Simple-geometry exciplex lamps of a novel type excited by a capacitive discharge (CD-excilamps) have been investigated. An efficient radiation has been obtained on KrBr*, KrCl*, XeBr*, XeCl* molecules and I* atom. The highest values of efficiency of various working molecules are approximately 10-18%. The lifetime of the operating gas mixture in KrCl*, XeCl*, I* and XeBr* exciplex lamps excited by a CD is above 1000 h. Owing to the above-mentioned characteristics, the exciplex lamps excited by a CD are supposed to be very promising for various applications

Eu/RG absorption and excitation spectroscopy in the solid rare gases: state dependence of crystal field splitting and Jahn-Teller coupling.

Science.gov (United States)

Byrne, Owen; McCaffrey, John G

2011-03-28

Absorption spectroscopy recorded for annealed samples of matrix-isolated atomic europium reveals a pair of thermally stable sites in Ar and Kr while a single site exists in Xe. Plots of the matrix shifts of the visible s → p bands versus host polarizability, allowed the association of the single site in Xe and the blue sites in Ar and Kr. On the basis of the similar ground state bond lengths expected for the Eu-rare gas (RG) diatomics and the known Na-RG molecules, the blue sites are attributed to Eu occupancy in the smaller tetra-vacancy while the red sites are proposed to arise from hexa-vacancy sites. Both sites are of cubic symmetry, consistent with the pronounced Jahn-Teller structure present on the y(8)P ← a(8)S(7/2) transition for these bands in the three hosts studied. Site-selective excitation spectroscopy has been used to reanalyze complex absorption spectra previously published by Jakob et al. [Phys. Lett. A 57, 67 (1976)] for the near-UV f → d transitions. On the basis that a pair of thermally stable sites exist in solid argon, the occurrence of crystal field splitting has been identified to occur for the J ≥ 5/2 level of the (8)P state when isolated in these two sites with cubic symmetry. From a detailed lineshape analysis, the magnitude of the crystal field splittings on the J = 5/2 level in Ar is found to be 105 and 123 cm(-1) for the red and blue sites, respectively.

XeBr exciplex laser

International Nuclear Information System (INIS)

Searles, S.K.

1976-01-01

Laser emission from the recently discovered XeBr exciplex laser was investigated as a function of the partial pressures of Xe and Br 2 . An optical loss process appears to limit high-pressure operation

Gaseous 83mKr generator for KATRIN

Science.gov (United States)

Sentkerestiová, J.; Dragoun, O.; Lebeda, O.; Ryšavý, M.; Sturm, M.; Vénos, D.

2018-04-01

Monoenergetic conversion electrons from the 83mKrKr isomeric state have been proven to be useful in the calibration of several tritium neutrino mass and dark matter experiments. In this paper the design and characteristics of the gaseous 83mKrKr generator, including the 83Rb/83mKrKr source behavior in tritium, for the KATRIN experiment are presented. Using Si(Li) and silicon drift detectors (SDD) detectors, the half-life of the 83mKrKr isomeric state was measured to be 1.8620 ± 0.0019 h.

Fast infrared spectroscopy in supercritical fluids

International Nuclear Information System (INIS)

Sun, X.

2000-05-01

Chapter 1: Introduction. A brief introduction to supercritical fluids is given, illustrating why supercritical fluids are unique solvents and why there is a wide application of supercritical fluids in industry and laboratories. Potential ways for solvation in supercritical fluids to affect reactivity are briefly reviewed. A general introduction to the photochemistry of organometallic complexes is also given. Chapter 2: Time resolved vibrational spectroscopy. Time resolved resonance Raman is introduced and compared with Time-resolved infrared spectroscopy (TRIR). The different approaches of TRIR, including microsecond, nanosecond, and ultrafast (picosecond and femtosecond) systems are discussed. The advantages and disadvantages of these systems are also compared. The TRIR apparatus using an IR diode laser used for work in this thesis are described in detail. Experimental procedures for supercritical fluid TRIR experiments are described with emphasis on handling the IR cell for supercritical fluids and preparation of supercritical fluid solutions. Chapter 3: Photochemistry of group VIB hexacarbonyl compounds in supercritical noble gases and CO 2 solutions. A systematic TRIR study of the photolysis of M(CO) 6 in supercritical Ar, Kr, Xe, and CO 2 and the observation of M(CO) 5 L (M = Cr, Mo, and W; L = Ar (W only), Kr, Xe, and CO 2 ) is described. The second-order rate constants for the reaction of M(CO) 5 L with CO have been evaluated and the reactivity for each metal is Kr > Xe ∼ CO 2 . For M(CO) 5 Kr, M(CO) 5 Xe, or M(CO) 5 (CO 2 ), the reactivity is Cr ∼ Mo > W. In supercritical Kr doped with either Xe or CO 2 , the M(CO) 5 moiety interacts with Xe or CO 2 in preference to Kr. The effect of solvent density on the rate of the reaction of W(CO) 5 (CO 2 ) with CO has been investigated. The reaction of W(CO) 5 (CO 2 ) with CO in scCO 2 is predominantly a dissociative process. The activation energies for the reaction of W(CO) 5 Xe and W(CO) 5 (CO 2 ) with CO and

Diffusion from a Ground Level Point Source Experiment with Thermoluminescence Dosimeters and Kr 85 as Tracer Substance

Energy Technology Data Exchange (ETDEWEB)

Ruden, B I

1969-06-15

In this report the theoretical conditions necessary for the study of the behaviour of released activity by the use of CaSO{sub 4}: Mn thermoluminescence dosimeters are considered. A method is derived for calculating exposure distributions from drifting volume activity. The correlation between exposure distributions and concentration distributions is discussed. One of thirty experiments where Br 82 was released into water through a nozzle some metres above the bottom is described. The resulting exposure distribution was measured in a vertical plane at distances of 10, 50 and 200 metres by CaSO{sub 4}: Mn thermoluminescence dosimeters. The measured exposures are described and discussed. The advantages and disadvantages of the technique are compared with other methods. The method using exposure measurements for the study of active release in water has given satisfactory results in practice. The measurements have been made at concentration levels which are considerably below that permissible for drinking water according to the recommendations by ICRPA special advantage with this method is that the measurements can be made simultaneously at a large number of places and that integration is possible over sufficiently long periods of time. An experiment is described where Ar 41 was released in free air at a height of one metre above ground and the resulting exposure distribution was measured in a vertical plane at 100 and 250 metres distance by CaSO{sub 4}: Mn thermoluminescence dosimeters. Shielding problems in connection with the experiments have been small since the method permits the measurement of very small doses. An account is given of the possibility of using the beta emitting isotope Kr 85 instead of the gamma emitting Ar 41 for diffusion experiments in air. The results obtained from some experiments are presented and discussed. The thermoluminescent signal from the dosimeters are, at the same concentration and exposure time, 2.5 times greater for Kr 85 than for

Multiple ionization of noble gases by 2.0 MeV proton impact: comparison with equi-velocity electron impact ionization

International Nuclear Information System (INIS)

Melo, W.S.; Santos, A.C.F.; Sant'Anna, M.M.; Sigaud, G.M.; Montenegro, E.C.

2002-01-01

Absolute single- and multiple-ionization cross sections of rare gases (He, Ne, Ar, Kr and Xe) have been measured for collisions with 2.0 MeV p + . A comparison is made with equi-velocity electron impact ionization cross sections as well as with the available proton impact data. For the light rare gases the single-ionization cross sections are essentially the same for both proton and electron impacts, but increasing differences appear for the heavier targets. (author). Letter-to-the-editor

Alkyne End Group Production in Polymeric Materials Induced by Swift Heavy Ion Irradiations

Institute of Scientific and Technical Information of China (English)

无

2001-01-01

Swift heavy ions in matter lose energy mainly through electronic processes.Since the energy deposition is centered in a very small region with a very high energy density,new effects such as production of alkyne end group can be induced.In this work,PET,PS,PC and PI films are irradiated with Ar,Kr,Xe and U ions and the relationship of the alkyne end group production with electronic energy loss is studied by Fourier transformed infrared infrared(FTLR)spectra measurements.

Vacuum ultraviolet emission from argon, krypton, and xenon in a radial-viewed theta pinch

International Nuclear Information System (INIS)

Engleman, R. Jr.; Thomson, D.B.; Monaghan, D.A.

1976-03-01

Vacuum ultraviolet line emission from argon, krypton, and xenon (5 percent in deuterium) has been observed from a plasma (approximately 50 eV and N/sub e/ approximately 10 17 /cm 3 ) produced by the Scyllar linear theta-pinch device. More than 50 emission lines in the 30- to 500-A region have been measured for each gas mixture. Some lines have been identified as due to Ar VII through XI, Kr IX and X, and Xe IX, but many lines remain unassigned

Determination of fission gas yields from isotope ratios

DEFF Research Database (Denmark)

Mogensen, Mogens Bjerg

1983-01-01

This paper describes a method of calculating the actual fission yield of Kr and Xe in nuclear fuel including the effect of neutron capture reactions and decay. The bases for this calculation are the cumulative yields (ref. 1) of Kr and Xe isotopes (or pairs of isotopes) which are unaffected...... by neutron capture reactions, and measured Kr and Xe isotope ratios. Also the burnup contribution from the different fissile heavy isotopes must be known in order to get accurate fission gas yields....

Measurement of the electron quenching rate in an electron beam pumped KrF* laser

International Nuclear Information System (INIS)

Nishioka, Hajime; Kurashima, Toshio; Kuranishi, Hideaki; Ueda, Kenichi; Takuma, Hiroshi; Sasaki, Akira; Kasuya, Koichi.

1988-01-01

The electron quenching rate of KrF * in an electron beam pumped laser has been studied by accurately measuring the saturation intensity in a mixture of Ar/Kr/F 2 = 94/6/0.284. The input intensity of the measurements was widely varied from 100 W cm -2 (small signal region) to 100 MW cm -2 (absorption dominant region) in order to separate laser parameters which are small signal gain coefficient, absorption coefficient, and saturation intensity from the measured net gain coefficients. The gas pressure and the pump rate were varied in the range of 0.5 to 2.5 atm and 0.3 to 1.4 MW cm -3 , respectively. The electron quenching rate constant of 4.5 x 10 -7 cm 3 s -1 was obtained from the pressure and the pump rate dependence of the KrF * saturation intensity with the temperature dependence of the rate gas 3-body quenching rate as a function of gas temperature to the -3rd power. The small signal gain coefficients calculated with the determined quenching rate constants shows excellent agreement with the measurements. (author)

Rb-129Xe spin-exchange rates due to binary and three-body collisions at high Xe pressures

International Nuclear Information System (INIS)

Cates, G.D.; Fitzgerald, R.J.; Barton, A.S.; Bogorad, P.; Gatzke, M.; Newbury, N.R.; Saam, B.

1992-01-01

We have studied the spin relaxation of 129 Xe nuclei due to collisions with Rb atoms at Xe pressures of 245--1817 Torr. Our results can be characterized by two parameters, the Rb- 129 Xe velocity-averaged binary spin-exchange cross section left-angle σv right-angle and a rate γ M that characterizes spin relaxation due to van der Waals molecules. Our results complement earlier studies performed at Xe pressures of about 1 Torr and N 2 pressures of 10--100 Torr. This work is useful for predicting spin-exchange rates between polarized Rb atoms and 129 Xe nuclei

3–10 keV Xe+ ion beam machining of ultra low thermal expansion glasses for EUVL projection optics: Evaluation of surface roughness

International Nuclear Information System (INIS)

Morikawa, K.; Kamijo, K.; Morijiri, K.; Pahlovy, S.A.; Aikawa, N.; Miyamoto, I.

2012-01-01

In order to obtain surface figure error of 0.15 nm rms and surface roughness (R rms ) of 0.12 nm rms for aspherical substrates in EUVL tools, ion beam figuring may be adopted to final surface figure error correction of aspherical substrates. During figure error correction, machined surface of the substrate becomes rougher than the pre-finished one. Therefore, we investigated the machined depth and ion energy dependences of R rms (measured by an AFM) of substrates machined by 3–10 keV Xe + ion beam, and compared them with the results obtained for Ar + ion beam. Result shows that the R rms s of CLEARCERAM®-Z, Zerodur® and ULE® substrates machined to the depth of 50 nm by 3–10 keV Xe + ion beam at the normal ion incidence angle become approximately 0.25, 0.28 and 0.15 nm rms, respectively. Those values are larger than the pre-finished substrates (0.07–0.09 nm rms), but smaller than that (0.60 nm rms for CLEARCERAM®-Z, 0.61 nm rms for Zerodur® and 0.18 nm rms for ULE®) of the substrates machined by Ar + ion beam. Moreover, the R rms s merely increase with increasing ion energy. The R rms s of the ULE® substrate machined by 3–10 keV Xe + ion beam rapidly increase with increasing machined depth, then saturate at machined depth of 10–50 nm. The saturated values of the R rms s are 0.12 and 0.15 nm rms for 3 and 10 keV Xe + ion beam respectively. We suggest that the 3 keV Xe + ion beam machining can be applicable for final shape correction of ULE® substrates for EUVL projection optics in association with considering further ultra smoothing process such as Si deposition or low energy ion beam smoothing.

Ar-37 in the Atmospheric and Sub-Soil Gases

International Nuclear Information System (INIS)

Purtschert, R.; Raghoo, L.S.

2015-01-01

On-site inspection of the radioactive noble gas isotope 37Ar is a definitive and unambiguous indicator of an underground nuclear explosion. 37Ar is produced underground by neutron activation of calcium by the reaction 40Ca(n,α)37Ar. In the atmosphere, 37Ar is produced by the spallation reaction 40Ar(n,4n)37Ar. Periodic measurements over the last six years on air collected in Bern revealed a background level in the order of 1-5 mBq/m 3 air in agreement with former findings and theoretical calculations. Those calculations also indicated that the intrusion of stratospheric air masses may lead to elevated tropospheric 37Ar concentrations up to 8-10 mBq/m 3 air. Selected samples taken up to now in the vicinity of nuclear power plants revealed no significant deviation from the natural background. In order to distinguish between natural and artificially elevated 37Ar the location-specific 37Ar activity range in soils, rocks and the atmosphere were identified. From CARIBIC flights, a passenger aircraft with a special air freight container filled with scientific equipment in the cargo compartment, tropospheric air samples were analyzed for 37Ar and 85Kr. The natural 37Ar production in soils and the rock basement underlying the alluvium is investigated by means of in situ measurements of different isotopes, theoretical calculations and irradiation experiments on selected rock samples. This will help resolve the temporal evolution and/or constancy of the natural 37Ar background and allow for an interpretation in terms of the identification of clandestine nuclear explosions. (author)

Energy levels and radiative rates for transitions in B-like to F-like Kr ions (Kr XXXII XXVIII)

Science.gov (United States)

Aggarwal, K. M.; Keenan, F. P.; Lawson, K. D.

2008-05-01

Energy levels, radiative rates, oscillator strengths, line strengths, and lifetimes have been calculated for transitions in B-like to F-like Kr ions, Kr XXXIII-XXVIII. For the calculations, the fully relativistic GRASP code has been adopted, and results are reported for all electric dipole (E1), electric quadrupole (E2), magnetic dipole (M1), and magnetic quadrupole (M2) transitions among the lowest 125, 236, 272, 226, and 113 levels of Kr XXXII, Kr XXXI, Kr XXX, Kr XXIX, and Kr XXVIII, respectively, belonging to the n ⩽ 3 configurations. Comparisons are made with earlier available theoretical and experimental results, and some discrepancies have been noted and explained.

Galatic and solar cosmic ray - produced rare gas isotopes in lunar fines

International Nuclear Information System (INIS)

Bhushan, B.N.; Rao, M.N.; Venkatesan, T.R.

1979-01-01

Lunar fines 10084, 14163 and 14148 from Apollo 11 and 14 missions as well as 24087 from Soviet Luna 24 mission have been studied for elemental and isotopic composition of He, Ne, Ar, Kr and Xe using milligram amounts by step-wise heating techniques. From these studies, the isotopic composition of solar wind has been determined and it is found to be in good agreement with the results reported by other workers. The experimental procedure adopted for studying these samples is described in brief. The use of a gas glass spectrometer for detecting the subtle galatic and solar cosmic ray xenon is explained. Data on the concentration and isotopic composition of selected isotopes of Xe and Ne in lunar fines is presented. (K.B.)

Cross-Section Measurements of the Kr86(γ,n) Reaction to Probe the s-Process Branching at Kr85

Science.gov (United States)

Raut, R.; Tonchev, A. P.; Rusev, G.; Tornow, W.; Iliadis, C.; Lugaro, M.; Buntain, J.; Goriely, S.; Kelley, J. H.; Schwengner, R.; Banu, A.; Tsoneva, N.

2013-09-01

We have carried out photodisintegration cross-section measurements on Kr86 using monoenergetic photon beams ranging from the neutron separation energy, Sn=9.86MeV, to 13 MeV. We combine our experimental Kr86(γ,n)Kr85 cross section with results from our recent Kr86(γ,γ') measurement below the neutron separation energy to obtain the complete nuclear dipole response of Kr86. The new experimental information is used to predict the neutron capture cross section of Kr85, an important branching point nucleus on the abundance flow path during s-process nucleosynthesis. Our new and more precise Kr85(n,γ)Kr86 cross section allows us to produce more precise predictions of the Kr86 abundance from s-process models. In particular, we find that the models of the s process in asymptotic giant branch stars of mass <1.5M⊙, where the C13 neutron source burns convectively rather than radiatively, represent a possible solution for the highest Kr86∶Kr82 ratios observed in meteoritic stardust SiC grains.

Cross-section measurements of the 86Kr(γ,n) reaction to probe the s-process branching at 85Kr.

Science.gov (United States)

Raut, R; Tonchev, A P; Rusev, G; Tornow, W; Iliadis, C; Lugaro, M; Buntain, J; Goriely, S; Kelley, J H; Schwengner, R; Banu, A; Tsoneva, N

2013-09-13

We have carried out photodisintegration cross-section measurements on 86Kr using monoenergetic photon beams ranging from the neutron separation energy, S(n) = 9.86  MeV, to 13 MeV. We combine our experimental 86Kr(γ,n)85Kr cross section with results from our recent 86Kr(γ,γ') measurement below the neutron separation energy to obtain the complete nuclear dipole response of 86Kr. The new experimental information is used to predict the neutron capture cross section of 85Kr, an important branching point nucleus on the abundance flow path during s-process nucleosynthesis. Our new and more precise 85Kr(n,γ)86Kr cross section allows us to produce more precise predictions of the 86Kr abundance from s-process models. In particular, we find that the models of the s process in asymptotic giant branch stars of mass <1.5M⊙, where the 13C neutron source burns convectively rather than radiatively, represent a possible solution for the highest 86Kr:82Kr ratios observed in meteoritic stardust SiC grains.

The possibility of lasing in Ne+Ar ionic molecules pumped by a hard ioniser

International Nuclear Information System (INIS)

Boichenko, Aleksandr M; Yakovlenko, Sergei I

2000-01-01

The kinetic model of relaxation in the Ne-Ar-Kr mixture pumped by a hard ioniser is constructed in connection with the analysis of the possibility of lasing at the Ne + Ar→NeAr + transition of the inert-gas ionic exciplexes. The calculations based on the typical rates of plasmachemical reactions demonstrate that the lasing is possible but difficult to realise: One needs high pressures (greater than 16 bar) and high pumping densities (∼ 1 MW cm -3 ). In the most favourable cases, the laser efficiency lies between 0.05 and 0.25%. (active media)

Kinetics of total body retention and clearance of xenon and krypton after inhalation

International Nuclear Information System (INIS)

Susskind, H.; Atkins, H.L.; Cohn, S.H.; Ellis, K.J.; Richards, P.

1976-01-01

The total body retention of Xe-127 and Kr-79 and their clearance rates following inhalation were measured in vivo. These data are useful for refined Xe-127 dosimetry calculations, to determine the potential radiation hazard of fission product Kr-85, and more generally to study the behavior of anesthetic gases. While data are available on the solubilities and partition coefficients of Xe and Kr in fat, blood, and other individual body constituents, few measurements of their retention and clearance from the entire body have been reported

Effect of orbital alignment on the forward and reverse electronic energy transfer Ca(4s5p 1P1)+Marrow-right-leftCa(4s5p 3P/sub J/)+M with rare gases

International Nuclear Information System (INIS)

Bussert, W.; Neuschaefer, D.; Leone, S.R.; Departments of Physics and Chemistry, University of Colorado, Boulder, Colorado 80309-0440)

1987-01-01

Effects of orbital alignment on the relative cross sections for electronic energy transfer are determined for the near resonant transfer between Ca(4s5p 1 P 1 ) and Ca(4s5p 3 P/sub J/) states with rare gas collision partners. The experiments are carried out by pulsed laser excitation in a crossed beam. The results for the forward direction, 1 P to 3 P, formulated in terms of the ratio of the maximum to minimum transfer probability are: 3 He 1.61 +- 0.05; He 1.60 +- 0.03; Ne 1.55 +- 0.10; Ar 1.52 +- 0.21; for Kr, transfer occurs, but no preference is distinguishable within 1 +- 0.2; Xe 1.44 +- 0.06. The results for He, Ne, and Ar indicate a clear preference in the transfer for the initially prepared molecular Pi state. For Xe the molecular Σ state is dominant. The energy transfer is also carried out in the reverse direction, 3 P 1 to 1 P, for He and Xe, obtaining 1.65 +- 0.10 and 1.94 +- 0.22, respectively. Analysis of the state preparation suggests that the reverse direction favors the asymptotic molecular Σ state for He and the molecular Pi state for Xe. These alignment results provide a first experimental determination of the dominant electronic states involved in a collisional energy transfer process

Determination of the separation efficiencies of a single-stage cryogenic distillation setup to remove krypton out of xenon by using a (83m)Kr tracer method.

Science.gov (United States)

Rosendahl, S; Brown, E; Cristescu, I; Fieguth, A; Huhmann, C; Lebeda, O; Murra, M; Weinheimer, C

2015-11-01

The separation of krypton and xenon is of particular importance for the field of direct dark matter search with liquid xenon detectors. The intrinsic contamination of the xenon with radioactive (85)Kr makes a significant background for these kinds of low count-rate experiments and has to be removed beforehand. This can be achieved by cryogenic distillation, a technique widely used in industry, using the different vapor pressures of krypton and xenon. In this paper, we present an investigation on the separation performance of a single stage distillation system using a radioactive (83m)Kr-tracer method. The separation characteristics under different operation conditions are determined for very low concentrations of krypton in xenon at the level of (83m)Kr/Xe = 1.9 ⋅ 10(-15), demonstrating, that cryogenic distillation in this regime is working. The observed separation is in agreement with the expectation from the different volatilities of krypton and xenon. This cryogenic distillation station is the first step on the way to a multi-stage cryogenic distillation column for the next generation of direct dark matter experiment XENON1T.

Multi-nucleon transfer reaions with heavy ions

International Nuclear Information System (INIS)

Nadkarni, D.M.

1975-01-01

The reaction mechanisms of multinucleon transfer reactions with heavy ions such as O 16 , Ne 22 , Ar 40 , Ge 74 , Kr 84 and Xe 136 are discussed. As an example, the transfer reactions of Th 232 bombarded with O 16 , Ne 22 and Ar 40 ions are described. Some general features and a semiclassical picture of these reactions are presented. Cross sections, energy spectra and angular distributions are derived for the products of these reactions. The energy dependence of nucleon transfer cross sections in the interaction of Ge 74 with Th 232 is discussed. The importance of the study of multinucleon transfer reactions in the production of neutron-rich isotopes and transuranium elements is pointed out. (A.K.)

Structure of high spin states of 76Kr and 78Kr nuclei

Indian Academy of Sciences (India)

Evolution of the shape with spin, and rotation alignment of proton as well as neutron ... by studying ground state properties of 76,78Kr by employing two sets of basis .... Figure 3. Energies of the yrast states of 76,78Kr nuclei compared with the.

XENON IN THE PROTOPLANETARY DISK (PPD-Xe)

Energy Technology Data Exchange (ETDEWEB)

Marti, K.; Mathew, K. J., E-mail: kattathu.mathew@srs.gov [Department of Chemistry and Biochemistry, University of California, San Diego, La Jolla, CA (United States)

2015-06-20

Relationships among solar system Xe components as observed in the solar wind, in planetary atmospheres, and in meteorites are investigated using isotopic correlations. The term PPD-Xe is used for components inferred to have been present in the molecular cloud material that formed the protoplanetary disk (PPD). The evidence of the lack of simple relationships between terrestrial atmospheric Xe and solar or meteoritic components is confirmed. Xe isotopic correlations indicate a heterogeneous PPD composition with variable mixing ratios of the nucleosynthetic component Xe-HL. Solar Xe represents a bulk PPD component, and the isotopic abundances did not change from the time of incorporation into the interior of Mars through times of regolith implantations to the present.

XENON IN THE PROTOPLANETARY DISK (PPD-Xe)

International Nuclear Information System (INIS)

Marti, K.; Mathew, K. J.

2015-01-01

Relationships among solar system Xe components as observed in the solar wind, in planetary atmospheres, and in meteorites are investigated using isotopic correlations. The term PPD-Xe is used for components inferred to have been present in the molecular cloud material that formed the protoplanetary disk (PPD). The evidence of the lack of simple relationships between terrestrial atmospheric Xe and solar or meteoritic components is confirmed. Xe isotopic correlations indicate a heterogeneous PPD composition with variable mixing ratios of the nucleosynthetic component Xe-HL. Solar Xe represents a bulk PPD component, and the isotopic abundances did not change from the time of incorporation into the interior of Mars through times of regolith implantations to the present

Xenon in the Protoplanetary Disk (PPD-Xe)

Science.gov (United States)

Marti, K.; Mathew, K. J.

2015-06-01

Relationships among solar system Xe components as observed in the solar wind, in planetary atmospheres, and in meteorites are investigated using isotopic correlations. The term PPD-Xe is used for components inferred to have been present in the molecular cloud material that formed the protoplanetary disk (PPD). The evidence of the lack of simple relationships between terrestrial atmospheric Xe and solar or meteoritic components is confirmed. Xe isotopic correlations indicate a heterogeneous PPD composition with variable mixing ratios of the nucleosynthetic component Xe-HL. Solar Xe represents a bulk PPD component, and the isotopic abundances did not change from the time of incorporation into the interior of Mars through times of regolith implantations to the present.

Development of intense high-energy noble gas ion beams from in-terminal ion injector of tandem accelerator using an ECR ion source

Energy Technology Data Exchange (ETDEWEB)

Matsuda, M., E-mail: matsuda.makoto@jaea.go.jp [Japan Atomic Energy Agency (JAEA), Tokai Research and Development Center, 2-4 Shirakata-shirane, Tokai, Naka, Ibaraki 319-1195 (Japan); Nakanoya, T.; Hanashima, S.; Takeuchi, S. [Japan Atomic Energy Agency (JAEA), Tokai Research and Development Center, 2-4 Shirakata-shirane, Tokai, Naka, Ibaraki 319-1195 (Japan)

2011-10-21

An ECRIS-based heavy ion injector was constructed in the high-voltage terminal of JAEA-Tokai Tandem Accelerator to develop new beam species of highly charged noble gas ions. This work was associated with a lot of development to operate the ion source on the 20UR Pelletron high voltage terminal in high pressure SF{sub 6} gas environment. Highly charged ions of N, O, Ne, Ar, Kr and Xe have been accelerated satisfactorily. Operating data integrated during many years long beam delivery service are summarized.

133Xe and 135Xe interference with in vivo low-energy measurement systems

International Nuclear Information System (INIS)

Cohen, N.; Lo Sasso, T.; Lei, W.

1980-01-01

Fission product 133 Xe and 135 Xe are released to the atmosphere during normal reactor operation. With increasing numbers of nuclear power stations there will be an increase in the ambient level of these isotopes. They do not present an appreciable long-term health hazard because of their inert nature and relatively short half-lives. However, their presence in the air of a whole-body counter may interfere significantly with in vivo low-energy photon counting procedures by contributing to the background count-rate in the energy region below 300 keV. This applies particularly to lung and whole-body measurements with dual thin crystal NaI(Tl)-CsI(Tl) scintillation detectors for actinide nuclides. It is important, therefore, that gamma spectroscopists should be aware of the possible presence of 133 Xe and 135 Xe in the air of their whole-body counting facilities, particularly if these are near to reactors and do not have traps for removal of inert gases from their air supplies. (author)

Measurement of the electron quenching rate in an electron beam pumped KrF/sup */ laser

Energy Technology Data Exchange (ETDEWEB)

Nishioka, Hajime; Kurashima, Toshio; Kuranishi, Hideaki; Ueda, Kenichi; Takuma, Hiroshi; Sasaki, Akira; Kasuya, Koichi.

1988-09-01

The electron quenching rate of KrF/sup */ in an electron beam pumped laser has been studied by accurately measuring the saturation intensity in a mixture of Ar/Kr/F/sub 2/ = 94/6/0.284. The input intensity of the measurements was widely varied from 100 W cm/sup -2/ (small signal region) to 100 MW cm/sup -2/ (absorption dominant region) in order to separate laser parameters which are small signal gain coefficient, absorption coefficient, and saturation intensity from the measured net gain coefficients. The gas pressure and the pump rate were varied in the range of 0.5 to 2.5 atm and 0.3 to 1.4 MW cm/sup -3/, respectively. The electron quenching rate constant of 4.5 x 10/sup -7/ cm/sup 3/s/sup -1/ was obtained from the pressure and the pump rate dependence of the KrF/sup */ saturation intensity with the temperature dependence of the rate gas 3-body quenching rate as a function of gas temperature to the -3rd power. The small signal gain coefficients calculated with the determined quenching rate constants shows excellent agreement with the measurements.

An improved method for 85Kr analysis by liquid scintillation counting and its application to atmospheric 85Kr determination

International Nuclear Information System (INIS)

Momoshima, Noriyuki; Inoue, Fumio; Sugihara, Shinji; Shimada, Jun; Taniguchi, Makoto

2010-01-01

Atmospheric 85 Kr concentration at Fukuoka, Japan was determined by an improved 85 Kr analytical method using liquid scintillation counting (LSC). An average value of 1.54 ± 0.05 Bq m -3 was observed in 2008, which is about two times that measured in 1981 at Fukuoka, indicating a 29 mBq y -1 rate of increase as an average for these 27 years. The analytical method developed involves collecting Kr from air using activated charcoal at liquid N 2 temperature and purifying it using He at dry ice temperature, followed by Kr separation by gas chromatography. An overall Kr recovery of 76.4 ± 8.1% was achieved when Kr was analyzed in 500-1000 l of air. The Kr isolated by gas chromatography was collected on silica gel in a quartz glass vial cooled to liquid N 2 temperature and the activity of 85 Kr was measured with a low-background LS counter. The detection limit of 85 Kr activity by the present analytical method is 0.0015 Bq at a 95% confidence level, including all propagation errors, which is equivalent with 85 Kr in 1.3 l of the present air under the analytical conditions of 72.1% counting efficiency, 0.1597 cps background count rate, and 76.4% Kr recovery.

Indirect Determination of Half-Lives of Short-Lived Fission Gases Using a Gas Flow Method; Determination Indirecte des Courtes PeRiodes de Produits de Fission Gazeux, par une Methode a Courant Gazeux; 041a 041e 0421 0412 0415 041d 041d 041e 0415 041e 041f 0420 0415 0414 0415 041b 0415 041d 0418 0415 041f 0415 0420 0418 041e 0414 041e 0412 041f 041e 041b 0423 0420 0410 0421 041f 0410 0414 0410 041a 041e 0420 041e 0422 041a 041e 0416 0418 0412 0423 0429 0418 0425 0413 0410 0417 041e - 041e 0411 0420 0410 0417 041d 042b 0425 041f 0420 041e 0414 0423 041a 0422 041e 0412 0414 0415 041b 0415 041d 0418 042f 0421 0418 0421 041f 041e 041b 042c 0417 041e 0412 0410 041d 0418 0415 041c 041c 0415 0422 041e 0414 041e 0412 0413 0410 0417 041e 0412 041e 0413 041e 041f 041e 0422 041e 041a 0410 ; Determinacion Indirecta del T 1/2 de los Cases de Fision de Periodo Corto por un Metodo de Circulacion

Energy Technology Data Exchange (ETDEWEB)

Patzelt, P.; Herrmann, G. [Institut fuer Anorganische Chemie und Kernchemie der Universitaet Mainz, Mainz, Federal Republic of Germany (Germany)

1965-07-15

Since the investigation of charge distribution in nuclear fission requires the determination of primary yields of individual fission products, which in most cases are either short-lived themselves or grow from shortlived precursors, very rapid and effective separations of neighbouring members of a fission chain have to be carried out. Making use of the extremely high emanating power of certain uranium compounds, separations are performed most easily for the fission gases In more than a dozen fission-product chains. Yield calculations as well as the effective emanating power of thick target layers, however, may be influenced considerably by the half-life data of the gases. Therefore the half-lives of the krypton and xenon isotopes Kr{sup 89}-Kr{sup 93} and Xe{sup 137}- X{sup 143} have been determined with great precision by using a rate-of-flow method in connection with an improved charged-electrode technique. Measurements were made via the active deposit of long-lived decay products on the electrodes. Flow- rare, irradiation time, cooling period and counting arrangements were chosen in such a way that measurements of individual daughter products became strongly favoured. In some cases, for reasons of selectivity, radiochemical separations proved to be indispensable. Results obtained are: Kr{sup 89}, 3.11 {+-} 0.06 min: Kr{sup 90}, 32.1 {+-} 0.8 s; Kr{sup 91}, 8.36 {+-} 0.15 s; Kr{sup 92}, 1,92 {+-} 0.07 s; Kr{sup 93}, 1.17 {+-} 0.04 s; Xe{sup 137}, 3.87 {+-} 0.15 min; Xe{sup 138}, 14.5 {+-} 0.5 min; Xe{sup 139}, 40.4 {+-} 1.3 s: Xe{sup 140}, 13.33 {+-} 0.27s; Xe{sup 141}, 1.70 {+-} 0.05s; Xe{sup 142}, 1.15 {+-} 0.04s- and Xe{sup 143}, 0.96 {+-} 0.02s. The half-lives were obtained by extrapolating the appropriate {beta}-decay curves or decay curves of y-peaks. The data listed are average values of a number of runs, resulting from a W{sub i} {approx} 1/o{sup 2} weighting procedure. All calculations were made at the computer centre of Mainz University. (author

The first example of commensurate adsorption of atomic gas in a MOF and effective separation of xenon from other noble gases

KAUST Repository

Wang, Hao; Yao, Kexin; Zhang, Zhijuan; Jagiełło, Jacek; Gong, Qihan; Han, Yu; Li, Jing

2014-01-01

demonstrates high adsorption capacity for xenon and its IAST selectivity for Xe-Kr is the largest among all MOFs investigated to date. To mimic real world conditions, breakthrough experiments are conducted on Xe-Kr binary mixtures at room temperature and 1

Yields and isomeric ratio of xenon and krypton isotopes from thermal neutron fission of 235U

International Nuclear Information System (INIS)

Hsu, S.S.; Lin, J.T.; Yang, C.M.; Yu, Y.W.

1981-01-01

The experimental cumulative yields of 85 Kr/sup m/, 87 Kr, 88 Kr, 133 Xe/sup g/, 135 Xe/sup m/, and 135 Xe/sup g/ and the independent isomeric yield of 133 Xe/sup m/ in the thermal neutron fission of 235 U have been measured by the gas chromatographic method. The independent yields of 133 Xe/sup g/, 135 Xe/sup m/, and 135 Xe/sup g/ were deduced with the aid of 133 I and 135 I data. The isomeric yield ratios of 133 Xe and 135 Xe have been computed and compared with theoretical values since they have the same high spin state J = 11/2 - and low spin ground state J = 3/2 + . The influence of the shell effect on the fission isomeric yield ratio is discussed. From the measured independent yield of Xe isotopes plus the reported data, the Xe-isotopic distribution curve has been constructed. The curve is compared with the isotopic distribution curves of Xe isotopes formed in 11.5 GeV proton interactions with 238 U and Cs isotopes formed in 24 GeV proton interactions with 238 U. Upon fitting the yield curves we find that only those products with N/Z> or =1.48 fit a curve typical of a binary fission process

High energy XeBr electric discharge laser

Science.gov (United States)

Sze, Robert C.; Scott, Peter B.

1981-01-01

A high energy XeBr laser for producing coherent radiation at 282 nm. The XeBr laser utilizes an electric discharge as the excitation source to minimize formation of molecular ions thereby minimizing absorption of laser radiation by the active medium. Additionally, HBr is used as the halogen donor which undergoes harpooning reactions with Xe.sub.M * to form XeBr*.

85Kr dating of groundwater

International Nuclear Information System (INIS)

Rozanski, K.; Florkowski, T.

1978-01-01

The possibility of 85 Kr dating of groundwater is being investigated. The method of gas extraction from 200 to 300 litres of water sample has been developed. The Argon and Krypton mixture, separated from the gas extracted from water, was counted in a 1.5 ml volume proportional counter. The amount of krypton gas in the counter was determined by mass spectrometry. A number of surface and groundwater samples were analyzed indicating an 85 Kr concentration ranging from present atmospheric content (river water) to zero values. 85 Kr 'blank value' was determined to be about 5 per cent of present 85 Kr atmospheric content. For groundwater samples, the mean residence time in the system was calculated assuming the exponential model and known 85 Kr input function. Further improvement of the method should bring higher yield of krypton separation and lower volume of water necessary for analysis. (orig.) [de

Cryotechnics used for activity retention in nuclear reactors and in the reprocessing of nuclear fuels

International Nuclear Information System (INIS)

Cavalieri, L.; Gutowski, H.; Patzelt, A.; Schroeder, E.

The use of low temperature technology for cleaning waste gas is demonstrated by four examples from nuclear technology: 1. Treatment of the gaseous fission products and oxyhydrogen gas components (catalytic H 2 oxidation, cold drying, Kr/Xe delay by adsorption) in the primary circuit of a 1300 MWe light water reactor. 2. Cleaning of the helium cooling gas of a high temperature reactor (delay adsorption for short-lived Kr/Xe isotopes, CO/H 2 oxidation CO 2 /H 2 O adsorption and finally low temperature adsorption of Kr/Xe/N 2 and N 2 recondensation). 3. Reprocessing of heavy water moderator by separation of the tritium with low temperature rectification and 4. Cleaning of solvent waste gas of a reprocessing plant (precleaning with various stages of process for separating aerosols, oil, Kr/Xe/N 2 , H 2 , NOsub(x) and low temperature rectification of krypton). (RB) [de

Electron thermalization in rare gases and their mixtures

International Nuclear Information System (INIS)

Bronic, I.K.; Kimura, M.

1996-01-01

The time evolution and temperature dependence of electron energy distribution functions (EDFs) are studied in pure rare gases (He, Ne, Ar, Kr, Xe) as well as in their mixtures by using solutions of the Boltzmann equation. A clear difference between the gases having the Ramsauer endash Townsend (RT) minimum in the momentum-transfer cross section, (RT gases: Ar, Kr, and Xe), and those without the RT minimum (non-RT gases: He and Ne) is pointed out. The influence of the position and the depth of the RT minimum on the EDF and time evolution is studied for three different initial electron energies. A formula proposed for describing thermalization time in a mixture is tested on (i) a non-RT endash non-RT gas mixture, (ii) a RT endash non-RT mixture and (iii) a RT endash RT gas mixture. The linear combination of the reciprocal thermalization times in gas mixture with the component concentrations as weighting factors is found to be valid for gases with a similar energy dependence of the momentum-transfer cross section, σ m , and also for all rare-gas binary mixtures if the initial electron energy is sufficiently below the RT minimum. Conspicuous deviations from the linear relationship are observed in mixtures of gases whose energy dependence of σ m (or the stopping cross section) are different, and theoretical rationales for these findings are provided. copyright 1996 American Institute of Physics

Rare-gas dependence of the self-quenching streamer

International Nuclear Information System (INIS)

Yoshioka, K.; Hashimoto, M.; Koori, N.; Kumabe, I.; Ohgaki, H.; Matoba, M.

1989-01-01

The self-quenching streamer (SQS) mode is understood these days as one of the basic modes of gas counter operation. In the present work, the SQS transition is clearly observed for Ar-, Kr- and Xe-mixtures with CH 4 , C 2 H 6 , C 3 H 8 , isoC 4 H 10 and CO 2 , and for He- and Ne-mixtures with C 2 H 6 , C 3 H 8 and isoC 4 H 10 . For He- and Ne-mixtures with CH 4 or CO 2 , the GM discharge is developed instead of the SQS transition. The avalanche size at the transition voltage decreases, in the order of He-, Ne-, Ar-, Kr- and Xe-mixtures, except for He-mixtures with CH 4 or CO 2 . The mechanisms of the SQS transition proposed by Atac et al. and Zhang have disadvantages in explaining all these results. If the photo-ionization is assumed as in Atac's mechanism, energetic photons whose yield is sufficiently large are needed for the SQS transition. The interaction between metastable states of rare gases proposed by Zhang may be energetically capable of producing electrons for the transition; effects of quenching gas in mixtures cannot be explained by this mechanism. Further investigation is necessary for microscopic processes occurring in the avalanche development. More detailed information is required on the atomic reaction cross sections of photo-ionization, radiative recombination, etc. (N.K.)

Spectroscopic Diagnostics of Barrier Discharge Plasmas in Mixtures of Zinc Diiodide with Inert Gases

International Nuclear Information System (INIS)

Guivan, N.N.; Malinin, A.N.

2005-01-01

The spectral characteristics of the emission of gas discharge atmospheric pressure plasmas in mixtures of zinc diiodide vapor with inert gases (He, Ne, Ar, Kr, and Xe) are investigated. The formation of a gas discharge plasma and the excitation of the components of a working mixture were performed in a high-frequency (with a repetition frequency of sinusoidal voltage pulses of 100 kHz) barrier discharge. The gas discharge emission was analyzed in the spectral range 200-900 nm with a resolution of 0.05 nm. Emission bands of ZnI(B-X) exciplex molecules and I* 2 excimer molecules, lines of inert gases, and emission bands of XeI* exciplex molecules (in Xe-containing mixtures) were revealed. It is ascertained that the strongest emission of ZnI* molecules is observed in ZnI 2 /He(Ne) mixtures. The regularities in the spectral characteristics of the gas discharge plasma emission are considered

C-14 and Ar-39 content in a ground water aquifer in the Saarland - comparison of two ground water isotope dating methods

International Nuclear Information System (INIS)

Forster, M.

1984-01-01

For the Ar-39 groundwater ages found an age comparison is made with ground waters investigated for C-14, Kr-85 and H-3 contents. The location of investigation is a sandstone aquifer of Southern Saarland. The underground production of Ar-39 the hydrological applicability. In granite, the average concentration of U, Th, K, and Cl with an average porosity of 1% and complete diffusion of the isotopes Ar-39 and Cl-36 produced underground can be as high as 10 5 % for Ar-39 moderated and 16% Cl-36 moderated in the interstitial water. (DG) [de

Analysis of 125Xe electron-photon coincidence decay

International Nuclear Information System (INIS)

Klingberg, F.J.; Biegalski, S.R.

2016-01-01

As part of the verification component of the Comprehensive Nuclear-Test-Ban Treaty (CTBT), environmental gas samples originating from nuclear fission are analyzed for the presence of 131m Xe, 133m Xe, 133 Xe, and 135 Xe. In this work, the non-traditional radioxenon isotope 125 Xe was investigated. The isotope was produced as an isotopically pure sample via neutron activation of 124 Xe at the University of Texas at Austin Nuclear Engineering Teaching Lab's TRIGA MARK II Reactor. The sample was then measured using a HPGe detector as well as an ARSA-style b-c coincidence detector. Potential sources and sensitivities for production of 125 Xe are also considered for relevance to the CTBT verification mission. (author)

Charge transfer reactions in Xe plasma expansion

International Nuclear Information System (INIS)

Jiao, C. Q.; Garscadden, A.; Ganguly, B. N.

2007-01-01

Charge transfer reactions of fast Xe ions with hydrocarbons including methane (CH 4 ), ethene (C 2 H 4 ), and propane (C 3 H 8 ) are studied by adding these hydrocarbon gases into a cross flowing Xe plasma expansion. Branching ratios and relative reaction rates for the charge transfers of fast Xe + with each of the three hydrocarbon gases are measured under different rf powers of the inductively coupled Xe discharge. For CH 4 /Xe system, we find that fast Xe + reacts readily with CH 4 generating CH 4 + and CH 3 + in a ratio of 1:0.56, with an estimated rate coefficient of (2.3±0.3)x10 -10 cm 3 /s at 75 W rf power which slowly increases to (2.9±0.3)x10 -10 cm 3 /s at 250 W (error bars reflect only the uncertainties due to the unknown extent of the ion recombination that follows the charge transfer reaction). These observed charge transfer reactions are made possible by the kinetically excited Xe ions produced by free expansion of the plasma. For the C 2 H 4 /Xe system product ions C 2 H 4 + and C 2 H 2 + are observed, and for C 3 H 8 /Xe, C 2 H 4 + and C 2 H 5 + and minor product ions including C 2 H 2 + and C 3 H 7 + are observed

Biological Studies with Laser-Polarized ^129Xe

Science.gov (United States)

Tseng, C. H.; Oteiza, E. R.; Wong, G. A.; Walsworth, R. L.; Albert, M. S.; Nascimben, L.; Peled, S.; Sakai, K.; Jolesz, F. A.

1996-05-01

We have studied several biological systems using laser-polarized ^129Xe. In certain tissues magnetic resonance imaging (MRI) using inhaled laser-polarized noble gases may provide images superior to those from conventional proton MRI. High resolution laser-polarized ^3He images of air spaces in the human lung were recently obtained by the Princeton/Duke group. However, ^3He is not very soluble in tissue. Therefore, we are using laser polarized ^129Xe (tissue-soluble), with the long term goal of biomedical functional imaging. We have investigated multi-echo and multi-excitation magnetic resonance detection schemes to exploit the highly non-thermal ^129Xe magnetization produced by the laser polarization technique. We have inhalated live rats with laser-polarized ^129Xe gas and measured three distinct ^129Xe tissue resonances that last 20 to 40 sec. As a demonstration, we obtained a laser polarized ^129Xe image of the human oral cavity. Currently we are measuring the polarization lifetime of ^129Xe dissolved in human blood, the biological transporting medium. These studies and other recent developments will be reported.

Kr atoms and their clustering in zeolite A

CERN Document Server

Lim, W T; Jung, K J; Heo, N H

2001-01-01

The positions of Kr atoms encapsulated in the molecular-dimensioned cavities of fully dehydrated zeolite A of unit-cell composition Cs sub 3 Na sub 8 HSi sub 1 sub 2 Al sub 1 sub 2 O sub 4 sub 8 (Cs sub 3 -A) have been determined. Cs sub 3 -A was exposed to 1025 atm of krypton gas at 400 .deg. C for four days, followed by cooling at pressure to encapsulate Kr atoms. The resulting crystal structure of Cs sub 3 -A(6Kr) (a=12.247(2) A, R sub 1 =0.078, and R sub 2 =0.085) has been determined by single-crystal X-ray diffraction techniques in the cubic space group Pm3m at 21(1) .deg. C and 1 atm. In the crystal structure of Cs sub 3 -A(6Kr), six Kr atoms per unit cell are distributed over three crystallographically distinct positions: each unit cell contains one Kr atom at Kr(1) on a threefold axis in the sodalite unit, three at Kr(2) opposite four-rings in the large cavity , and two at Kr(3) on threefold axes in the large cavity . Relatively strong interactions of Kr atoms at Kr(1) and Kr(3) with Na sup + ions of ...

Emission characteristics of Xe-RbBr plasma

Science.gov (United States)

Heneral, A. A.; Avtaeva, S. V.

2017-12-01

The luminescence spectra of the longitudinal pulsed-periodic discharge in Xe-RbBr gas-vapour mixtures at low pressures are experimentally studied. Conditions for obtaining strong UV radiation of XeBr* exiplex molecules in the spectral range of 200-425 nm are found. The greatest output of the XeBr* UV radiation is provided at temperature of the gas-discharge tube walls of ~1000 K. The maximum UV emission power of the whole plasma volume is 4.8 W. Formation of XeBr* exciplex molecules in the pulsed-periodic discharge in Xe-RbBr gas-vapour mixtures at low pressures is discussed.

Neutron capture cross sections of Kr

Directory of Open Access Journals (Sweden)

Fiebiger Stefan

2017-01-01

Full Text Available Neutron capture and β− -decay are competing branches of the s-process nucleosynthesis path at 85Kr [1], which makes it an important branching point. The knowledge of its neutron capture cross section is therefore essential to constrain stellar models of nucleosynthesis. Despite its importance for different fields, no direct measurement of the cross section of 85Kr in the keV-regime has been performed. The currently reported uncertainties are still in the order of 50% [2, 3]. Neutron capture cross section measurements on a 4% enriched 85Kr gas enclosed in a stainless steel cylinder were performed at Los Alamos National Laboratory (LANL using the Detector for Advanced Neutron Capture Experiments (DANCE. 85Kr is radioactive isotope with a half life of 10.8 years. As this was a low-enrichment sample, the main contaminants, the stable krypton isotopes 83Kr and 86Kr, were also investigated. The material was highly enriched and contained in pressurized stainless steel spheres.

Collisions of halogen (2P) and rare gas (1S) atoms

International Nuclear Information System (INIS)

Becker, C.H.

1978-12-01

Differential cross sections I (THETA) at several collision energies measured in crossed molecular beam experiments are reported for several combinations of halogen atoms ( 2 P) scattered off rare gas-rare gas atoms ( 1 S 0 ), namely, F + Ne, F + Ar, F + Kr, F + Xe, C1 + Xe. The scattering is described by an elastic model appropriate to Hund's case c coupling. With the use of this model, the X 1/2, I 3/2, and II 1/2 interaction potential energy curves are derived by fitting calculated differential cross sections, based on analytic representations of the potentials, to the data. The F - Xe X 1/2 potential shows a significant bonding qualitatively different than for the other F-rare gases. The I 3/2 and II 1/2 potentials closely resemble the van der Waals interactions of the one electron richer ground state rare gas-rare gas systems. Coupled-channel scattering calculations are carried out for F + Ar, F + Xe, and C1 + Xe using the realistic potential curves derived earlier. The results justify the use of the elastic model, and give additional information on intramultiplet and intermultiplet transitions. The transitions are found to be governed by the crossing of the two Ω = 1/2 potentials in the complex plane. The measured I (theta) and I (THETA) derived from the coupled-channel computations show small oscillations or perturbations (Stueckelberg oscillations) though quantitative agreement is not obtained.The nature of the anomalous F - Xe X 1/2 potential is discussed as is the approximation of a constant spin orbit coupling over the experimentally accessible range of internuclear distances for these open shell molecules. 55 references

Geophysical borehole logging and optical imaging of the boreholes KR34, KR35 and KR36, at Olkiluoto 2005

International Nuclear Information System (INIS)

Majapuro, J.

2005-09-01

Suomen Malmi Oy conducted geophysical borehole logging and optical imaging surveys of the boreholes KR34, KR35 and KR36 at the Olkiluoto site in Eurajoki during May - June 2005. The survey is a part of Posiva Oy's detailed investigation program for the final disposal of spent nuclear fuel. The methods applied are magnetic susceptibility, natural gamma radiation, gamma-gamma density, single point resistance, Wenner-resistivity, borehole radar, full waveform sonic and optical imaging. The assignment included the field work of all surveys, interpretation and processing of the acoustic and borehole radar data. The report describes the field operation, equipment as well as processing procedures and shows the obtained results and their quality in the appendices. The raw and processed data are delivered digitally in WellCAD and Excel format. (orig.)

Geophysical borehole logging and optical imaging of the boreholes KR34, KR35 and KR36, at Olkiluoto 2005

Energy Technology Data Exchange (ETDEWEB)

Majapuro, J. [Suomen Malmi Oy, Espoo (Finland)

2005-09-15

Suomen Malmi Oy conducted geophysical borehole logging and optical imaging surveys of the boreholes KR34, KR35 and KR36 at the Olkiluoto site in Eurajoki during May - June 2005. The survey is a part of Posiva Oy's detailed investigation program for the final disposal of spent nuclear fuel. The methods applied are magnetic susceptibility, natural gamma radiation, gamma-gamma density, single point resistance, Wenner-resistivity, borehole radar, full waveform sonic and optical imaging. The assignment included the field work of all surveys, interpretation and processing of the acoustic and borehole radar data. The report describes the field operation, equipment as well as processing procedures and shows the obtained results and their quality in the appendices. The raw and processed data are delivered digitally in WellCAD and Excel format. (orig.)

Computation of Ion Charge State Distributions After Inner-shell Ionization in Ne, Ar and Kr Atoms Using Monte Carlo Simulation

International Nuclear Information System (INIS)

Ahmed Ghoneim, Adel Aly; Ghoneim, Adel A.; Al-Zanki, Jasem M.; El-Essawy, Ashraf H.

2009-01-01

Atomic reorganization starts by filling the initially inner-shell vacancy by a radiative transition (x-ray) or by a non-radiative transition (Auger and Coster-Kronig processes). New vacancies created during this atomic reorganization may in turn be filled by further radiative and non-radiative transitions until all vacancies reach the outermost occupied shells. The production of inner-shell vacancy in an atom and the de-excitation decays through radiative and non-radiative transitions may result in a change of the atomic potential; this change leads to the emission of an additional electron in the continuum (electron shake-off processes). In the present work, the ion charge state distributions (CSD) and mean atomic charge ions produced from inner shell vacancy de-excitation decay are calculated for neutral Ne , Ar and Kr atoms. The calculations are carried out using Monte Carlo (MC) technique to simulate the cascade development after primary vacancy production. The radiative and non-radiative transitions for each vacancy are calculated in the simulation. In addition, the change of transition energies and transition rates due to multi vacancies produced in the atomic configurations through the cascade development are considered in the present work. It is found that considering the electron shake off process and closing of non-allowed non-radiative channels improves the results of both charge state distributions (CSD) and average charge state. To check the validity of the present calculations, the results obtained are compared with available theoretical and experimental data. The present results are found to agree well with the available theoretical and experimental values. (author)

Ārpus klases aktivitātes pamatskolas skolēnu angļu valodas vārdu krājuma bagātināšanai

OpenAIRE

Kalniņa, Maija

2012-01-01

Diplomdarba autore četru pedagoģiskā darba gadu laikā ir secinājusi, cik svarīgi ir plānot stundas ne tikai interesantas un interaktīvas, bet arī praktiskas un pēc iespējas tuvākas reālajai dzīvei. Diplomdarba mērķis ir noskaidrot, kā ārpusklases nodarbības var uzlabot skolēnu angļu valodas vārdu krājumu pamatskolā. Šāda diplomdarba tēma tika izvēlēta tādēļ, ka vārdu krājuma bagātināšanai ir liela nozīme angļu valodas apguvē, kā arī, lai skolēni spētu veiksmīgi izmantot angļu valodu,...

Production yields of noble-gas isotopes from ISOLDE UC$_{x}$/graphite targets

CERN Document Server

Bergmann, U C; Catherall, R; Cederkäll, J; Diget, C A; Fraile-Prieto, L M; Franchoo, S; Fynbo, H O U; Gausemel, H; Georg, U; Giles, T; Hagebø, E; Jeppesen, H B; Jonsson, O C; Köster, U; Lettry, Jacques; Nilsson, T; Peräjärvi, K; Ravn, H L; Riisager, K; Weissman, L; Äystö, J

2003-01-01

Yields of He, Ne, Ar, Kr and Xe isotopic chains were measured from UC$_{x}$/graphite and ThC$_{x}$/graphite targets at the PSB-ISOLDE facility at CERN using isobaric selectivity achieved by the combination of a plasma-discharge ion source with a water-cooled transfer line. %The measured half-lives allowed %to calculate the decay losses of neutron-rich isotopes in the %target and ion-source system, and thus to obtain information on the in-target %productions from the measured yields. The delay times measured for a UC$_x$/graphite target allow for an extrapolation to the expected yields of very neutron-rich noble gas isotopes, in particular for the ``NuPECC reference elements'' Ar and Kr, at the next-generation radioactive ion-beam facility EURISOL. \\end{abstract} \\begin{keyword} % keywords here, in the form: keyword \\sep keyword radioactive ion beams \\sep release \\sep ion yields \\sep ISOL (Isotope Separation On-Line) \\sep uranium and thorium carbide targets. % PACS codes here, in the form: \\PACS code \\sep code...

Mass and charge distribution in heavy-ion collisions

International Nuclear Information System (INIS)

Beck, F.; Dworzecka, M.; Feldmeier, H.

1978-01-01

A statistical model based on the independent particle picture is used to calculate mass and charge distributions in deep inelastic heavy-ion collisions. Different assumptions on volume and charge equilibrations are compared with measured variances of charge distributions. One combination of assumptions is clearly favoured by experiment, and gives a reasonable description of the variance versus energy loss curves up to energy losses of about 200 MeV in the heavy systems Kr+Ho and Xe+Bi, and up to about 60 MeV for the light system Ar+Ca [af

The energy broadening resulting from electron stripping process of a low energy Au- beam

International Nuclear Information System (INIS)

Taniike, Akira; Sasao, Mamiko; Hamada, Yasuji; Fujita, Junji; Wada, Motoi.

1994-12-01

Energy loss spectra of Au + ions produced from Au - ions by electron stripping in He, Ar, Kr and Xe have been measured in the impact energy range of 24-44 keV. The energy broadening of the Au + beam increases as the beam energy increases, and the spectrum shows a narrower energy width for heavy target atoms. The dependence of the spectrum width upon the beam energy and that upon the target mass are well described by the calculation based on the unified potential and semi-classical internal energy transfer model of Firsov's. (author)

O2(X3 Sigma- sub g) and O2(a1 Delta sub g) Charge Exchange with Simple Ions (Postprint)

Science.gov (United States)

2014-06-03

injected into a flow tube through a Venturi inlet. The ions were carried downstream by the helium buffer gas . The O2(X3−g )/O2(a 1g) mixture was added...However, for this study, the procedure needed to be modified as explained below. Most of the gas was pumped away by a roots blower and a small amount was...Publishing Articles you may be interested in Mutual neutralization of atomic rare- gas cations (Ne+, Ar+, Kr+, Xe+) with atomic halide anions (Cl−, Br−, I

A 223-nm KrCl excimer laser on a He-Kr-HCl mixture

International Nuclear Information System (INIS)

Razhev, A M; Zhupikov, A A; Kargapol'tsev, E S

2004-01-01

The results of experimental studies of the parameters of a 223-nm electric-discharge KrCl excimer laser on a He-Kr-HCl mixture depending on the excitation conditions and the composition of the active gaseous medium are presented. To achieve the maximum values of the output energy and the efficiency of the KrCl laser on mixtures with buffer gaseous helium, an excitation system was used that included a circuit with an LC inverter with a high-voltage switch based on an RU-65 spark gap. An output energy of 320 mJ with an efficiency of 0.5% relative to the energy stored in the capacitors is obtained in a KrCl laser with an active medium based on the buffer He gas at a charging voltage of 30 kV. Radiation pulses with a duration of 22±1 ns and a pulse power of 15 MW are obtained. (lasers)

On the size and structure of helium snowballs formed around charged atoms and clusters of noble gases.

Science.gov (United States)

Bartl, Peter; Leidlmair, Christian; Denifl, Stephan; Scheier, Paul; Echt, Olof

2014-09-18

Helium nanodroplets doped with argon, krypton, or xenon are ionized by electrons and analyzed in a mass spectrometer. HenNgx(+) ions containing up to seven noble gas (Ng) atoms and dozens of helium atoms are identified; the high resolution of the mass spectrometer combined with advanced data analysis make it possible to unscramble contributions from isotopologues that have the same nominal mass but different numbers of helium or Ng atoms, such as the magic He20(84)Kr2(+) and the isobaric, nonmagic He41(84)Kr(+). Anomalies in these ion abundances reveal particularly stable ions; several intriguing patterns emerge. Perhaps most astounding are the results for HenAr(+), which show evidence for three distinct, solid-like solvation shells containing 12, 20, and 12 helium atoms. This observation runs counter to the common notion that only the first solvation shell is solid-like but agrees with calculations by Galli et al. for HenNa(+) [J. Phys. Chem. A 2011, 115, 7300] that reveal three shells of icosahedral symmetry. HenArx(+) (2 ≤ x ≤ 7) ions appear to be especially stable if they contain a total of n + x = 19 atoms. A sequence of anomalies in the abundance distribution of HenKrx(+) suggests that rings of six helium atoms are inserted into the solvation shell each time a krypton atom is added to the ionic core, from Kr(+) to Kr3(+). Previously reported strong anomalies at He12Kr2(+) and He12Kr3(+) [Kim , J. H.; et al. J. Chem. Phys. 2006, 124, 214301] are attributed to a contamination. Only minor local anomalies appear in the distributions of HenXex(+) (x ≤ 3). The distributions of HenKr(+) and HenXe(+) show strikingly similar, broad features that are absent from the distribution of HenAr(+); differences are tentatively ascribed to the very different fragmentation dynamics of these ions.

Syntheses, Raman spectra, and X-ray crystal structures of [XeF(5)][mu-F(OsO(3)F(2))(2)] and [M][OsO(3)F(3)] (M = XeF(5)(+), Xe(2)F(11)(+)).

Science.gov (United States)

Hughes, Michael J; Mercier, Hélène P A; Schrobilgen, Gary J

2010-04-05

Stoichiometric amounts of XeF(6) and (OsO(3)F(2))(infinity) react at 25-50 degrees C to form salts of the known XeF(5)(+) and Xe(2)F(11)(+) cations, namely, [XeF(5)][mu-F(OsO(3)F(2))(2)], [XeF(5)][OsO(3)F(3)], and [Xe(2)F(11)][OsO(3)F(3)]. Although XeF(6) is oxophilic toward a number of transition metal and main-group oxides and oxide fluorides, fluoride/oxide metathesis was not observed. The series provides the first examples of noble-gas cations that are stabilized by metal oxide fluoride anions and the first example of a mu-F(OsO(3)F(2))(2)(-) salt. Both [XeF(5)][mu-F(OsO(3)F(2))(2)] and [Xe(2)F(11)][OsO(3)F(3)] are orange solids at room temperature. The [XeF(5)][OsO(3)F(3)] salt is an orange liquid at room temperature that solidifies at 5-0 degrees C. When the salts are heated at 50 degrees C under 1 atm of N(2) for more than 2 h, significant XeF(6) loss occurs. The X-ray crystal structures (-173 degrees C) show that the salts exist as discrete ion pairs and that the osmium coordination spheres in OsO(3)F(3)(-) and mu-F(OsO(3)F(2))(2)(-) are pseudo-octahedral OsO(3)F(3)-units having facial arrangements of oxygen and fluorine atoms. The mu-F(OsO(3)F(2))(2)(-) anion is comprised of two symmetry-related OsO(3)F(2)-groups that are fluorine-bridged to one another. Ion pairing results from secondary bonding interactions between the fluorine/oxygen atoms of the anions and the xenon atom of the cation, with the Xe...F/O contacts occurring opposite the axial fluorine and from beneath the equatorial XeF(4)-planes of the XeF(5)(+) and Xe(2)F(11)(+) cations so as to avoid the free valence electron lone pairs of the xenon atoms. The xenon atoms of [XeF(5)][mu-F(OsO(3)F(2))(2)] and [Xe(2)F(11)][OsO(3)F(3)] are nine-coordinate and the xenon atom of [XeF(5)][OsO(3)F(3)] is eight-coordinate. Quantum-chemical calculations at SVWN and B3LYP levels of theory were used to obtain the gas-phase geometries, vibrational frequencies, and NBO bond orders, valencies, and NPA charges of

Production of highly charged ion beams from ECR ion sources

International Nuclear Information System (INIS)

Xie, Z.Q.

1997-09-01

Electron Cyclotron Resonance (ECR) ion source development has progressed with multiple-frequency plasma heating, higher mirror magnetic fields and better technique to provide extra cold electrons. Such techniques greatly enhance the production of highly charged ions from ECR ion sources. So far at cw mode operation, up to 300 eμA of O 7+ and 1.15 emA of O 6+ , more than 100 eμA of intermediate heavy ions for charge states up to Ar 13+ , Ca 13+ , Fe 13+ , Co 14+ and Kr 18+ , and tens of eμA of heavy ions with charge states to Kr 26+ , Xe 28+ , Au 35+ , Bi 34+ and U 34+ have been produced from ECR ion sources. At an intensity of at least 1 eμA, the maximum charge state available for the heavy ions are Xe 36+ , Au 46+ , Bi 47+ and U 48+ . An order of magnitude enhancement for fully stripped argon ions (I ≥ 60 enA) also has been achieved. This article will review the ECR ion source progress and discuss key requirement for ECR ion sources to produce the highly charged ion beams

Production of highly charged ion beams from electron cyclotron resonance ion sources (invited)

International Nuclear Information System (INIS)

Xie, Z.Q.

1998-01-01

Electron cyclotron resonance ion source (ECRIS) development has progressed with multiple-frequency plasma heating, higher mirror magnetic fields, and better technique to provide extra cold electrons. Such techniques greatly enhance the production of highly charged ions from ECRISs. So far at continuous wave (CW) mode operation, up to 300 eμA of O 7+ and 1.15 emA of O 6+ , more than 100 eμA of intermediate heavy ions for charge states up to Ar 13+ , Ca 13+ , Fe 13+ , Co 14+ , and Kr 18+ , and tens of eμA of heavy ions with charge states to Kr 26+ , Xe 28+ , Au 35+ , Bi 34+ , and U 34+ were produced from ECRISs. At an intensity of at least 1 eμA, the maximum charge state available for the heavy ions are Xe 36+ , Au 46+ , Bi 47+ , and U 48+ . An order of magnitude enhancement for fully stripped argon ions (I≥60enA) were also achieved. This article will review the ECR ion source progress and discuss key requirement for ECRISs to produce the highly charged ion beams. copyright 1998 American Institute of Physics

Orestes Kinetics Model for the Electra KrF Laser

Science.gov (United States)

Giuliani, J. L.; Kepple, P.; Lehmberg, R. H.; Myers, M. C.; Sethian, J. D.; Petrov, G.; Wolford, M.; Hegeler, F.

2003-10-01

Orestes is a first principles simulation code for the electron deposition, plasma chemistry, laser transport, and amplified spontaneous emission (ASE) in an e-beam pumped KrF laser. Orestes has been benchmarked against results from Nike at NRL and the Keio laser facility. The modeling tasks are to support ongoing oscillator experiments on the Electra laser ( 500 J), to predict performance of Electra as an amplifier, and to develop scaling relations for larger systems such as envisioned for an inertial fusion energy power plant. In Orestes the energy deposition of the primary beam electrons is assumed to be spatially uniform, but the excitation and ionization of the Ar/Kr/F2 target gas by the secondary electrons is determined from the energy distribution function as calculated by a Boltzmann code. The subsequent plasma kinetics of 23 species subject to over 100 reactions is followed with 1-D spatial resolution along the lasing axis. In addition, the vibrational relaxation among excited electronic states of the KrF molecule are included in the kinetics since lasing at 248 nm can occur from several vibrational lines of the B state. Transport of the lasing photons is solved by the method of characteristics. The time dependent ASE is calculated in 3-D using a ``local look-back'' scheme with discrete ordinates and includes specular reflection off the side walls and rear mirror. Gain narrowing is treated by multi-frequency transport of the ASE. Calculations for the gain, saturation intensity, extraction efficiency, and laser output from the Orestes model will be presented and compared with available data from Electra operated as an oscillator. Potential implications for the difference in optimal F2 concentration will be discussed along with the effects of window transmissivity at 248 nm.

Precipitation of Kr after implantation into Al

International Nuclear Information System (INIS)

Birtcher, R.C.; Jaeger, W.

1985-09-01

Transmission electron microscopy (TEM) was used to perform a systematic study of the microstructural evolution in Al as a function of the fluence received during 65 keV Kr + ion implantation at room temperature. At the lower fluences (2 x 10 16 to 2 x 10 19 Kr + m -2 ), isolated dislocation loops and the evolution of a dislocation network was observed by TEM. Above fluences of 10 19 Kr + m -2 , the microstructure is dominated by a high density of Kr bubbles whose average size increases with dose. The appearance of additional electron diffraction reflections indicates that the majority of the bubbles contain solid fcc Kr that is epitaxially aligned with the fcc Al matrix. Above fluences of 2 x 10 20 Kr + m -2 an increasing fraction of the Kr is in a liquid or gas-like phase. The thermal stability of the microstructure, characteristic of the different fluence regimes, was investigated up to 640 0 C by in situ TEM annealing experiments

Hydraulic conductivity measurements with HTU at Eurajoki, Olkiluoto, drillholes OL-KR19, OL-KR45 and OL-KR46 in 2009 and 2010

Energy Technology Data Exchange (ETDEWEB)

Haemaelaeinen, H. [Geopros Oy, Helsinki (Finland)

2011-10-15

As a part of the site investigations for the disposal of spent nuclear fuel, hydraulic conductivity measurements were carried out with HTU-equipment in drillholes OL-KR19, OL-KR45 and OL-KR46 at Eurajoki, Olkiluoto. The objective was to investigate the distribution of the hydraulic conductivity in the surrounding bedrock volume. Measurements were carried out during 2009 and 2010. The total length of the borehole OL-KR19 is 544,34 m, 241,80 m of which was covered by 121 standard tests with 2 m packer separation as specified in the measurement plan. Respectively, OL-KR45 is 1023,30 m long and 63 similar tests were made in it covering 126,00 m of the hole and OL-KR46 600,10 m long, 151 tests made covering 301,35 m. The measured sections are around the depths of the planned repository. Double-packer constant-head method was used throughout with nominal 200 kPa overpressure. Injection stage lasted normally 20 minutes and fall-off stage 10 minutes. The tests were often shortened if there were clear indications that the hydraulic conductivity is below the measuring range of the system. The pressure in the test section was let to stabilise at least 5 min before injection. In some test sections the test stage times were extended. Two transient (Horner and 1/Q) interpretations and one stationary- state (Moye) interpretation were made in-situ immediately after the test. The Hydraulic Testing Unit (HTU-system) is owned by Posiva Oy and it was operated by Geopros Oy. (orig.)

Excess heat production in Pd/D during periodic pulse discharge current in various conditions

International Nuclear Information System (INIS)

Karabut, A.B.

2006-01-01

Experimental date from low-energy nuclear reactions (LENR) in condensed media are presented. The nuclear reactions products were found in solid cathode media used in glow discharge. Apparently, the nuclear reactions were initiated when bombarding the cathode surface by plasma ions with the energy of 1.0 - 2.0 keV. Excess heat from a high current glow discharge reaction in D 2 , Xe, and Kr using cathodes already charged with preliminary deuterium-charged Pd and Ti cathode samples are given. Excess heat up to 10-15 W and efficiency up to 130% were recorded under the experiments for Pd cathode samples in D 2 discharge. Excess heat up to 5 W and efficiency up to 150% were recorded for Pd cathodes that were charged with deuterium before the run, in Xe and Kr discharges. At the same time excess heat was not observed for pure Pd cathode samples in Xe and Kr discharges. The formation of impurity nuclides ( 7 Li, 13 C, 15 N, 20 Ne, 29 Si, 44 Ca, 48 Ca, 56 Fe, 57 Fe, 59 Co, 64 Zn, 66 Zn, 75 As, 107 Ag, 109 Ag, 110 Cd, 111 Cd, 112 Cd, 114 Cd and 115 In) with 'the efficiency up to 10 13 at./s was recorded. The isotopic ratios of these new nuclides were quite different from the natural ratios. Soft X-ray radiation from the solid-state cathode with the intensity up to 0.01 Gy/s was recorded in experiments with discharges in H 2 , D 2 , Ar, Xe, and Kr. The X-ray radiation was observed in bursts of up to 10 6 photons, with up to 10 5 bursts per second while the discharge was formed and within 100 ms after turning off the discharge current. The results of the X-ray radiation registration showed that the excited energy levels have a lifetime up to 100 ms or more, and the energy of 1.2 - 2.5 keV. A possible mechanism for producing excess heat and nuclear transmutation reactions in the solid medium with the excited energy levels is considered

Indirect processes in electron impact ionization of Kr24+ and Kr25+

International Nuclear Information System (INIS)

Chen, M.H.; Reed, K.J.

1992-09-01

Electron-impact ionization cross sections have been calculated for magnesiumlike Kr 24+ and sodiumlike Kr 25+ . Electron-impact ionization is an important atomic process in hot dense plasmas. It can affect the ionization balance, electron temperature, electron density, and level population in the plasma. In the past decade, theoretical and experimental studies have revealed that indirect processes can make significant contributions to the cross sections for electron impact ionization of positive ions. The most important indirect process is excitation of an inner-shell electron followed by Auger emission. Higher-order processes such as resonant excitation followed by sequential double Auger emission, can also contribute significantly. The contributions of excitation-autoionization and resonant excitation double autoionization (REDA) were included, in addition to the cross sections for direct ionization of a 3s electron. The calculations were carried out using the relativistic distorted wave methods and the multiconfiguration Dirac-Fock model. For Kr 25+ , the total cross section is about 5 times the direct ionization cross section. For the Kr 24+ , the indirect contribution is about 2.5 times the direct ionization cross section. The REDA process produces many strong resonances and contributes about 20% to the average ionization cross section

Detection of fuel element failures at the gas cooled reactors; Zaznavanje razpok na gorilnih elementih plinsko hlajenega reaktorja

Energy Technology Data Exchange (ETDEWEB)

Bremsak, P; Ranzel, S; Ogrin, R; Pisanski, C [Institut Jozef Stefan, Ljubljana (Yugoslavia)

1964-07-01

This paper describes the system for measuring the concentration of released Kr and Xe in the cooling gas. The system developed in the Jozef Stefan Institute is efficient and suitable for application The method is based on electrostatic collection of daughter elements from radioactive decay of Xe and Kr.

Detection of fuel element failures at the gas cooled reactors

International Nuclear Information System (INIS)

Bremsak, P.; Ranzel, S.; Ogrin, R.; Pisanski, C.

1964-01-01

This paper describes the system for measuring the concentration of released Kr and Xe in the cooling gas. The system developed in the Jozef Stefan Institute is efficient and suitable for application The method is based on electrostatic collection of daughter elements from radioactive decay of Xe and Kr

Charged particle suppression in Pb+Pb and Xe+Xe collisions measured with the ATLAS detector

CERN Document Server

Balek, Petr; The ATLAS collaboration

2018-01-01

The measurement of charge particle production in heavy ion collisions, when compared with pp data, provides insight into the properties of the hot and dense quark-gluon plasma. The ATLAS detector at the LHC recorded 0.49 nb$^{−1}$ of Pb+Pb collisions and 4.2 pb$^{−1}$ of pp collisions, both at the center-of-mass energy $\\sqrt{s}=\\sqrt{s_{NN}}=5.02$ TeV. Recently, ATLAS also recorded 3 $\\mu$b$^{−1}$ of Xe+Xe collisions at $\\sqrt{s_{NN}}=5.44$ TeV, which offers a new opportunity to study the system size dependence of the parton energy loss. The large acceptance of the ATLAS detector allows measurements of charged hadron spectra in a wide range of both pseudorapidity and transverse momentum, differentially in collision centrality. The charged hadron spectra measured in Pb+Pb and Xe+Xe collisions are compared to the analogous spectra measured in pp collisions, and the resulting nuclear modification factors $R_{AA}$ are studied.

An improved method for {sup 85}Kr analysis by liquid scintillation counting and its application to atmospheric {sup 85}Kr determination

Energy Technology Data Exchange (ETDEWEB)

Momoshima, Noriyuki, E-mail: momoshima.noriyuki.551@m.kyushu-u.ac.j [Radioisotope Center, Kyushu University, 6-10-1 Hakozaki, Higashi-ku, Fukuoka 812-8581 (Japan); Inoue, Fumio [Graduate School of Science, Kyushu University, 6-10-1Hakozaki, Higashi-ku, Fukuoka 812-8581 (Japan); Sugihara, Shinji [Radioisotope Center, Kyushu University, 6-10-1 Hakozaki, Higashi-ku, Fukuoka 812-8581 (Japan); Shimada, Jun [Graduate School of Science and Technology, Kumamoto University, 2-39-1 Kurokami, Kumamoto 860-8555 (Japan); Taniguchi, Makoto [Research Institute for Humanity and Nature, 457-4 Motoyama Kamigamo, Kita-ku, Kyoto 603-8047 (Japan)

2010-08-15

Atmospheric {sup 85}Kr concentration at Fukuoka, Japan was determined by an improved {sup 85}Kr analytical method using liquid scintillation counting (LSC). An average value of 1.54 {+-} 0.05 Bq m{sup -3} was observed in 2008, which is about two times that measured in 1981 at Fukuoka, indicating a 29 mBq y{sup -1} rate of increase as an average for these 27 years. The analytical method developed involves collecting Kr from air using activated charcoal at liquid N{sub 2} temperature and purifying it using He at dry ice temperature, followed by Kr separation by gas chromatography. An overall Kr recovery of 76.4 {+-} 8.1% was achieved when Kr was analyzed in 500-1000 l of air. The Kr isolated by gas chromatography was collected on silica gel in a quartz glass vial cooled to liquid N{sub 2} temperature and the activity of {sup 85}Kr was measured with a low-background LS counter. The detection limit of {sup 85}Kr activity by the present analytical method is 0.0015 Bq at a 95% confidence level, including all propagation errors, which is equivalent with {sup 85}Kr in 1.3 l of the present air under the analytical conditions of 72.1% counting efficiency, 0.1597 cps background count rate, and 76.4% Kr recovery.

Thermoluminescence study of lithium fluorides

CERN Document Server

Abu-Alazm, S M

2003-01-01

The spectrum of the light emitted during thermoluminescence (TL) from irradiated lif sample with different doses of Xe, Kr and electrons have been studied. The results show a main peak for all samples irradiated and unirradiated at temperature about 200 degree C. Morcever when the reaches to the value 5x10 sup 1 1 ion/cm sup 2 a new two bands begin to appear in case of Xe and Kr ion irradiation. The TL spectra under Kr and Xe ion irradiation similar at the same dose. However, the spectra under electron irradiation were found to be rather different than under heavy ions irradiation.

Electron-Impact Ionization Cross Sections of H, He, N, O, Ar, Xe, Au, Pb Atoms and Their Ions in the Electron Energy Range from the Threshold up to 200 keV

CERN Document Server

Povyshev, V M; Shevelko, V P; Shirkov, G D; Vasina, E G; Vatulin, V V

2001-01-01

Single electron-impact ionization cross sections of H, He, N, O, Ar, Xe, Au, Pb atoms and their positive ions (i.e. all ionization stages) are presented in the electron energy range from the threshold up to 200 keV. The data-set for the cross sections has been created on the basis of available experimental data and calculations performed by the computer code ATOM. Consistent data for the ionization cross sections have been fitted by seven parameters using the LSM method. The accuracy of the calculated data presented is within a factor of 2 that in many cases is sufficient to solve the plasma kinetics problems. Contributions from excitation-autoionization and resonant-ionization processes as well as ionization of atoms and ions are not considered here. The results of the numerical calculations are compared with the well-known Lotz formulae for ionization of neutral atoms and positive ions. The material is illustrated by figures and includes tables of ionization cross sections, binding energies and fitting para...

Soft x-ray source by laser produced Xe plasma

International Nuclear Information System (INIS)

Amano, Sho; Masuda, Kazuya; Miyamoto, Shuji; Mochizuki, Takayasu

2010-01-01

The laser plasma soft X-ray source in the wavelength rage of 5-17 nm was developed, which consisted of the rotating drum system supplying cryogenic Xe target and the high repetition rate pulse Nd:YAG slab laser. We found the maximum conversion efficiency of 30% and it demonstrated the soft X-ray generation with the high repetition rate pulse of 320 pps and the high average power of 20 W. The soft X-ray cylindrical mirror was developed and successfully focused the soft X-ray with an energy intensity of 1.3 mJ/cm 2 . We also succeeded in the plasma debris mitigation with Ar gas. This will allow a long lifetime of the mirror and a focusing power intensity of 400 mW/cm 2 with 320 pps. The high power soft X-ray is useful for various applications. (author)

Inclusive J/$\\psi$ production in Xe-Xe collisions at $\\sqrt{s_{NN}}$ = 5.44 TeV

CERN Document Server

Acharya, Shreyasi; The ALICE collaboration; Adamova, Dagmar; Adolfsson, Jonatan; Aggarwal, Madan Mohan; Aglieri Rinella, Gianluca; Agnello, Michelangelo; Agrawal, Neelima; Ahammed, Zubayer; Ahn, Sang Un; Aiola, Salvatore; Akindinov, Alexander; Al-turany, Mohammad; Alam, Sk Noor; Silva De Albuquerque, Danilo; Aleksandrov, Dmitry; Alessandro, Bruno; Alfaro Molina, Jose Ruben; Ali, Yasir; Alici, Andrea; Alkin, Anton; Alme, Johan; Alt, Torsten; Altenkamper, Lucas; Altsybeev, Igor; Anaam, Mustafa Naji; Andrei, Cristian; Andreou, Dimitra; Andrews, Harry Arthur; Andronic, Anton; Angeletti, Massimo; Anguelov, Venelin; Anson, Christopher Daniel; Anticic, Tome; Antinori, Federico; Antonioli, Pietro; Anwar, Rafay; Apadula, Nicole; Aphecetche, Laurent Bernard; Appelshaeuser, Harald; Arcelli, Silvia; Arnaldi, Roberta; Arnold, Oliver Werner; Arsene, Ionut Cristian; Arslandok, Mesut; Audurier, Benjamin; Augustinus, Andre; Averbeck, Ralf Peter; Azmi, Mohd Danish; Badala, Angela; Baek, Yong Wook; Bagnasco, Stefano; Bailhache, Raphaelle Marie; Bala, Renu; Baldisseri, Alberto; Ball, Markus; Baral, Rama Chandra; Barbano, Anastasia Maria; Barbera, Roberto; Barile, Francesco; Barioglio, Luca; Barnafoldi, Gergely Gabor; Barnby, Lee Stuart; Ramillien Barret, Valerie; Bartalini, Paolo; Barth, Klaus; Bartsch, Esther; Bastid, Nicole; Basu, Sumit; Batigne, Guillaume; Batyunya, Boris; Batzing, Paul Christoph; Bazo Alba, Jose Luis; Bearden, Ian Gardner; Beck, Hans; Bedda, Cristina; Behera, Nirbhay Kumar; Belikov, Iouri; Bellini, Francesca; Bello Martinez, Hector; Bellwied, Rene; Espinoza Beltran, Lucina Gabriela; Belyaev, Vladimir; Bencedi, Gyula; Beole, Stefania; Bercuci, Alexandru; Berdnikov, Yaroslav; Berenyi, Daniel; Bertens, Redmer Alexander; Berzano, Dario; Betev, Latchezar; Bhaduri, Partha Pratim; Bhasin, Anju; Bhat, Inayat Rasool; Bhatt, Himani; Bhattacharjee, Buddhadeb; Bhom, Jihyun; Bianchi, Antonio; Bianchi, Livio; Bianchi, Nicola; Bielcik, Jaroslav; Bielcikova, Jana; Bilandzic, Ante; Biro, Gabor; Biswas, Rathijit; Biswas, Saikat; Blair, Justin Thomas; Blau, Dmitry; Blume, Christoph; Boca, Gianluigi; Bock, Friederike; Bogdanov, Alexey; Boldizsar, Laszlo; Bombara, Marek; Bonomi, Germano; Bonora, Matthias; Borel, Herve; Borissov, Alexander; Borri, Marcello; Botta, Elena; Bourjau, Christian; Bratrud, Lars; Braun-munzinger, Peter; Bregant, Marco; Broker, Theo Alexander; Broz, Michal; Brucken, Erik Jens; Bruna, Elena; Bruno, Giuseppe Eugenio; Budnikov, Dmitry; Buesching, Henner; Bufalino, Stefania; Buhler, Paul; Buncic, Predrag; Busch, Oliver; Buthelezi, Edith Zinhle; Bashir Butt, Jamila; Buxton, Jesse Thomas; Cabala, Jan; Caffarri, Davide; Caines, Helen Louise; Caliva, Alberto; Calvo Villar, Ernesto; Soto Camacho, Rabi; Camerini, Paolo; Capon, Aaron Allan; Carena, Francesco; Carena, Wisla; Carnesecchi, Francesca; Castillo Castellanos, Javier Ernesto; Castro, Andrew John; Casula, Ester Anna Rita; Ceballos Sanchez, Cesar; Chandra, Sinjini; Chang, Beomsu; Chang, Wan; Chapeland, Sylvain; Chartier, Marielle; Chattopadhyay, Subhasis; Chattopadhyay, Sukalyan; Chauvin, Alex; Cheshkov, Cvetan Valeriev; Cheynis, Brigitte; Chibante Barroso, Vasco Miguel; Dobrigkeit Chinellato, David; Cho, Soyeon; Chochula, Peter; Chowdhury, Tasnuva; Christakoglou, Panagiotis; Christensen, Christian Holm; Christiansen, Peter; Chujo, Tatsuya; Chung, Suh-urk; Cicalo, Corrado; Cifarelli, Luisa; Cindolo, Federico; Cleymans, Jean Willy Andre; Colamaria, Fabio Filippo; Colella, Domenico; Collu, Alberto; Colocci, Manuel; Concas, Matteo; Conesa Balbastre, Gustavo; Conesa Del Valle, Zaida; Contreras Nuno, Jesus Guillermo; Cormier, Thomas Michael; Corrales Morales, Yasser; Cortese, Pietro; Cosentino, Mauro Rogerio; Costa, Filippo; Costanza, Susanna; Crkovska, Jana; Crochet, Philippe; Cuautle Flores, Eleazar; Cunqueiro Mendez, Leticia; Dahms, Torsten; Dainese, Andrea; Dani, Sanskruti; Danisch, Meike Charlotte; Danu, Andrea; Das, Debasish; Das, Indranil; Das, Supriya; Dash, Ajay Kumar; Dash, Sadhana; De, Sudipan; De Caro, Annalisa; De Cataldo, Giacinto; De Conti, Camila; De Cuveland, Jan; De Falco, Alessandro; De Gruttola, Daniele; De Marco, Nora; De Pasquale, Salvatore; Derradi De Souza, Rafael; Franz Degenhardt, Hermann; Deisting, Alexander; Deloff, Andrzej; Delsanto, Silvia; Deplano, Caterina; Dhankher, Preeti; Di Bari, Domenico; Di Mauro, Antonio; Di Ruzza, Benedetto; Arteche Diaz, Raul; Dietel, Thomas; Dillenseger, Pascal; Ding, Yanchun; Divia, Roberto; Djuvsland, Oeystein; Dobrin, Alexandru Florin; Domenicis Gimenez, Diogenes; Donigus, Benjamin; Dordic, Olja; Van Doremalen, Lennart Vincent; Dubey, Anand Kumar; Dubla, Andrea; Ducroux, Laurent; Dudi, Sandeep; Duggal, Ashpreet Kaur; Dukhishyam, Mallick; Dupieux, Pascal; Ehlers Iii, Raymond James; Elia, Domenico; Endress, Eric; Engel, Heiko; Epple, Eliane; Erazmus, Barbara Ewa; Erhardt, Filip; Ersdal, Magnus Rentsch; Espagnon, Bruno; Eulisse, Giulio; Eum, Jongsik; Evans, David; Evdokimov, Sergey; Fabbietti, Laura; Faggin, Mattia; Faivre, Julien; Fantoni, Alessandra; Fasel, Markus; Feldkamp, Linus; Feliciello, Alessandro; Feofilov, Grigorii; Fernandez Tellez, Arturo; Ferretti, Alessandro; Festanti, Andrea; Feuillard, Victor Jose Gaston; Figiel, Jan; Araujo Silva Figueredo, Marcel; Filchagin, Sergey; Finogeev, Dmitry; Fionda, Fiorella; Fiorenza, Gabriele; Flor, Fernando; Floris, Michele; Foertsch, Siegfried Valentin; Foka, Panagiota; Fokin, Sergey; Fragiacomo, Enrico; Francescon, Andrea; Francisco, Audrey; Frankenfeld, Ulrich Michael; Fronze, Gabriele Gaetano; Fuchs, Ulrich; Furget, Christophe; Furs, Artur; Fusco Girard, Mario; Gaardhoeje, Jens Joergen; Gagliardi, Martino; Gago Medina, Alberto Martin; Gajdosova, Katarina; Gallio, Mauro; Duarte Galvan, Carlos; Ganoti, Paraskevi; Garabatos Cuadrado, Jose; Garcia-solis, Edmundo Javier; Garg, Kunal; Gargiulo, Corrado; Gasik, Piotr Jan; Gauger, Erin Frances; De Leone Gay, Maria Beatriz; Germain, Marie; Ghosh, Jhuma; Ghosh, Premomoy; Ghosh, Sanjay Kumar; Gianotti, Paola; Giubellino, Paolo; Giubilato, Piero; Glassel, Peter; Gomez Coral, Diego Mauricio; Gomez Ramirez, Andres; Gonzalez, Victor; Gonzalez Zamora, Pedro; Gorbunov, Sergey; Gorlich, Lidia Maria; Gotovac, Sven; Grabski, Varlen; Graczykowski, Lukasz Kamil; Graham, Katie Leanne; Greiner, Leo Clifford; Grelli, Alessandro; Grigoras, Costin; Grigoryev, Vladislav; Grigoryan, Ara; Grigoryan, Smbat; Gronefeld, Julius Maximilian; Grosa, Fabrizio; Grosse-oetringhaus, Jan Fiete; Grosso, Raffaele; Guernane, Rachid; Guerzoni, Barbara; Guittiere, Manuel; Gulbrandsen, Kristjan Herlache; Gunji, Taku; Gupta, Anik; Gupta, Ramni; Bautista Guzman, Irais; Haake, Rudiger; Habib, Michael Karim; Hadjidakis, Cynthia Marie; Hamagaki, Hideki; Hamar, Gergoe; Hamid, Mohammed; Hamon, Julien Charles; Hannigan, Ryan; Haque, Md Rihan; Harris, John William; Harton, Austin Vincent; Hassan, Hadi; Hatzifotiadou, Despina; Hayashi, Shinichi; Heckel, Stefan Thomas; Hellbar, Ernst; Helstrup, Haavard; Herghelegiu, Andrei Ionut; Gonzalez Hernandez, Emma; Herrera Corral, Gerardo Antonio; Herrmann, Florian; Hetland, Kristin Fanebust; Hilden, Timo Eero; Hillemanns, Hartmut; Hills, Christopher; Hippolyte, Boris; Hohlweger, Bernhard; Horak, David; Hornung, Sebastian; Hosokawa, Ritsuya; Hota, Jyotishree; Hristov, Peter Zahariev; Huang, Chun-lu; Hughes, Charles; Huhn, Patrick; Humanic, Thomas; Hushnud, Hushnud; Hussain, Nur; Hussain, Tahir; Hutter, Dirk; Hwang, Dae Sung; Iddon, James Philip; Iga Buitron, Sergio Arturo; Ilkaev, Radiy; Inaba, Motoi; Ippolitov, Mikhail; Islam, Md Samsul; Ivanov, Marian; Ivanov, Vladimir; Izucheev, Vladimir; Jacak, Barbara; Jacazio, Nicolo; Jacobs, Peter Martin; Jadhav, Manoj Bhanudas; Jadlovska, Slavka; Jadlovsky, Jan; Jaelani, Syaefudin; Jahnke, Cristiane; Jakubowska, Monika Joanna; Janik, Malgorzata Anna; Jena, Chitrasen; Jercic, Marko; Jevons, Oliver; Jimenez Bustamante, Raul Tonatiuh; Jin, Muqing; Jones, Peter Graham; Jusko, Anton; Kalinak, Peter; Kalweit, Alexander Philipp; Kang, Ju Hwan; Kaplin, Vladimir; Kar, Somnath; Karasu Uysal, Ayben; Karavichev, Oleg; Karavicheva, Tatiana; Karczmarczyk, Przemyslaw; Karpechev, Evgeny; Kebschull, Udo Wolfgang; Keidel, Ralf; Keijdener, Darius Laurens; Keil, Markus; Ketzer, Bernhard Franz; Khabanova, Zhanna; Khan, Ahsan Mehmood; Khan, Shaista; Khan, Shuaib Ahmad; Khanzadeev, Alexei; Kharlov, Yury; Khatun, Anisa; Khuntia, Arvind; Kielbowicz, Miroslaw Marek; Kileng, Bjarte; Kim, Byungchul; Kim, Daehyeok; Kim, Dong Jo; Kim, Eun Joo; Kim, Hyeonjoong; Kim, Jinsook; Kim, Jiyoung; Kim, Minjung; Kim, Se Yong; Kim, Taejun; Kim, Taesoo; Kirsch, Stefan; Kisel, Ivan; Kiselev, Sergey; Kisiel, Adam Ryszard; Klay, Jennifer Lynn; Klein, Carsten; Klein, Jochen; Klein-boesing, Christian; Klewin, Sebastian; Kluge, Alexander; Knichel, Michael Linus; Knospe, Anders Garritt; Kobdaj, Chinorat; Varga-kofarago, Monika; Kohler, Markus Konrad; Kollegger, Thorsten; Kondratyeva, Natalia; Kondratyuk, Evgeny; Konevskikh, Artem; Konyushikhin, Maxim; Kovalenko, Oleksandr; Kovalenko, Vladimir; Kowalski, Marek; Kralik, Ivan; Kravcakova, Adela; Kreis, Lukas; Krivda, Marian; Krizek, Filip; Kruger, Mario; Kryshen, Evgeny; Krzewicki, Mikolaj; Kubera, Andrew Michael; Kucera, Vit; Kuhn, Christian Claude; Kuijer, Paulus Gerardus; Kumar, Jitendra; Kumar, Lokesh; Kumar, Shyam; Kundu, Sourav; Kurashvili, Podist; Kurepin, Alexander; Kurepin, Alexey; Kuryakin, Alexey; Kushpil, Svetlana; Kvapil, Jakub; Kweon, Min Jung; Kwon, Youngil; La Pointe, Sarah Louise; La Rocca, Paola; Lai, Yue Shi; Lakomov, Igor; Langoy, Rune; Lapidus, Kirill; Lara Martinez, Camilo Ernesto; Lardeux, Antoine Xavier; Larionov, Pavel; Laudi, Elisa; Lavicka, Roman; Lea, Ramona; Leardini, Lucia; Lee, Seongjoo; Lehas, Fatiha; Lehner, Sebastian; Lehrbach, Johannes; Lemmon, Roy Crawford; Leon Monzon, Ildefonso; Levai, Peter; Li, Xiaomei; Li, Xing Long; Lien, Jorgen Andre; Lietava, Roman; Lim, Bong-hwi; Lindal, Svein; Lindenstruth, Volker; Lindsay, Scott William; Lippmann, Christian; Lisa, Michael Annan; Litichevskyi, Vladyslav; Liu, Alwina; Ljunggren, Hans Martin; Llope, William; Lodato, Davide Francesco; Loginov, Vitaly; Loizides, Constantinos; Loncar, Petra; Lopez, Xavier Bernard; Lopez Torres, Ernesto; Lowe, Andrew John; Luettig, Philipp Johannes; Luhder, Jens Robert; Lunardon, Marcello; Luparello, Grazia; Lupi, Matteo; Maevskaya, Alla; Mager, Magnus; Mahmood, Sohail Musa; Maire, Antonin; Majka, Richard Daniel; Malaev, Mikhail; Malik, Qasim Waheed; Malinina, Liudmila; Mal'kevich, Dmitry; Malzacher, Peter; Mamonov, Alexander; Manko, Vladislav; Manso, Franck; Manzari, Vito; Mao, Yaxian; Marchisone, Massimiliano; Mares, Jiri; Margagliotti, Giacomo Vito; Margotti, Anselmo; Margutti, Jacopo; Marin, Ana Maria; Markert, Christina; Marquard, Marco; Martin, Nicole Alice; Martinengo, Paolo; Martinez, Jacobb Lee; Martinez Hernandez, Mario Ivan; Martinez-garcia, Gines; Martinez Pedreira, Miguel; Masciocchi, Silvia; Masera, Massimo; Masoni, Alberto; Massacrier, Laure Marie; Masson, Erwann; Mastroserio, Annalisa; Mathis, Andreas Michael; Toledo Matuoka, Paula Fernanda; Matyja, Adam Tomasz; Mayer, Christoph; Mazzilli, Marianna; Mazzoni, Alessandra Maria; Meddi, Franco; Melikyan, Yuri; Menchaca-rocha, Arturo Alejandro; Meninno, Elisa; Mercado-perez, Jorge; Meres, Michal; Soncco Meza, Carlos; Mhlanga, Sibaliso; Miake, Yasuo; Micheletti, Luca; Mieskolainen, Matti Mikael; Mihaylov, Dimitar Lubomirov; Mikhaylov, Konstantin; Mischke, Andre; Mishra, Aditya Nath; Miskowiec, Dariusz Czeslaw; Mitra, Jubin; Mitu, Ciprian Mihai; Mohammadi, Naghmeh; Mohanty, Auro Prasad; Mohanty, Bedangadas; Khan, Mohammed Mohisin; Moreira De Godoy, Denise Aparecida; Perez Moreno, Luis Alberto; Moretto, Sandra; Morreale, Astrid; Morsch, Andreas; Muccifora, Valeria; Mudnic, Eugen; Muhlheim, Daniel Michael; Muhuri, Sanjib; Mukherjee, Maitreyee; Mulligan, James Declan; Gameiro Munhoz, Marcelo; Munning, Konstantin; Arratia Munoz, Miguel Ignacio; Munzer, Robert Helmut; Murakami, Hikari; Murray, Sean; Musa, Luciano; Musinsky, Jan; Myers, Corey James; Myrcha, Julian Wojciech; Naik, Bharati; Nair, Rahul; Nandi, Basanta Kumar; Nania, Rosario; Nappi, Eugenio; Narayan, Amrendra; Naru, Muhammad Umair; Nassirpour, Adrian Fereydon; Ferreira Natal Da Luz, Pedro Hugo; Nattrass, Christine; Rosado Navarro, Sebastian; Nayak, Kishora; Nayak, Ranjit; Nayak, Tapan Kumar; Nazarenko, Sergey; Negrao De Oliveira, Renato Aparecido; Nellen, Lukas; Nesbo, Simon Voigt; Neskovic, Gvozden; Ng, Fabian; Nicassio, Maria; Niedziela, Jeremi; Nielsen, Borge Svane; Nikolaev, Sergey; Nikulin, Sergey; Nikulin, Vladimir; Noferini, Francesco; Nomokonov, Petr; Nooren, Gerardus; Cabanillas Noris, Juan Carlos; Norman, Jaime; Nyanin, Alexander; Nystrand, Joakim Ingemar; Oh, Hoonjung; Ohlson, Alice Elisabeth; Oleniacz, Janusz; Oliveira Da Silva, Antonio Carlos; Oliver, Michael Henry; Onderwaater, Jacobus; Oppedisano, Chiara; Orava, Risto; Oravec, Matej; Ortiz Velasquez, Antonio; Oskarsson, Anders Nils Erik; Otwinowski, Jacek Tomasz; Oyama, Ken; Pachmayer, Yvonne Chiara; Pacik, Vojtech; Pagano, Davide; Paic, Guy; Palni, Prabhakar; Pan, Jinjin; Pandey, Ashutosh Kumar; Panebianco, Stefano; Papikyan, Vardanush; Pareek, Pooja; Park, Jonghan; Parkkila, Jasper Elias; Parmar, Sonia; Passfeld, Annika; Pathak, Surya Prakash; Patra, Rajendra Nath; Paul, Biswarup; Pei, Hua; Peitzmann, Thomas; Peng, Xinye; Pereira, Luis Gustavo; Pereira Da Costa, Hugo Denis Antonio; Peresunko, Dmitry Yurevich; Perez Lezama, Edgar; Peskov, Vladimir; Pestov, Yury; Petracek, Vojtech; Petrovici, Mihai; Petta, Catia; Peretti Pezzi, Rafael; Piano, Stefano; Pikna, Miroslav; Pillot, Philippe; Ozelin De Lima Pimentel, Lais; Pinazza, Ombretta; Pinsky, Lawrence; Pisano, Silvia; Piyarathna, Danthasinghe; Ploskon, Mateusz Andrzej; Planinic, Mirko; Pliquett, Fabian; Pluta, Jan Marian; Pochybova, Sona; Podesta Lerma, Pedro Luis Manuel; Poghosyan, Martin; Polishchuk, Boris; Poljak, Nikola; Poonsawat, Wanchaloem; Pop, Amalia; Poppenborg, Hendrik; Porteboeuf, Sarah Julie; Pozdniakov, Valeriy; Prasad, Sidharth Kumar; Preghenella, Roberto; Prino, Francesco; Pruneau, Claude Andre; Pshenichnov, Igor; Puccio, Maximiliano; Punin, Valery; Putschke, Jorn Henning; Raha, Sibaji; Rajput, Sonia; Rak, Jan; Rakotozafindrabe, Andry Malala; Ramello, Luciano; Rami, Fouad; Raniwala, Rashmi; Raniwala, Sudhir; Rasanen, Sami Sakari; Rascanu, Bogdan Theodor; Ratza, Viktor; Ravasenga, Ivan; Read, Kenneth Francis; Redlich, Krzysztof; Rehman, Attiq Ur; Reichelt, Patrick Simon; Reidt, Felix; Ren, Xiaowen; Renfordt, Rainer Arno Ernst; Reshetin, Andrey; Revol, Jean-pierre; Reygers, Klaus Johannes; Riabov, Viktor; Richert, Tuva Ora Herenui; Richter, Matthias Rudolph; Riedler, Petra; Riegler, Werner; Riggi, Francesco; Ristea, Catalin-lucian; Rode, Sudhir Pandurang; Rodriguez Cahuantzi, Mario; Roeed, Ketil; Rogalev, Roman; Rogochaya, Elena; Rohr, David Michael; Roehrich, Dieter; Rokita, Przemyslaw Stefan; Ronchetti, Federico; Dominguez Rosas, Edgar; Roslon, Krystian; Rosnet, Philippe; Rossi, Andrea; Rotondi, Alberto; Roukoutakis, Filimon; Roy, Christelle Sophie; Roy, Pradip Kumar; Vazquez Rueda, Omar; Rui, Rinaldo; Rumyantsev, Boris; Rustamov, Anar; Ryabinkin, Evgeny; Ryabov, Yury; Rybicki, Andrzej; Saarinen, Sampo; Sadhu, Samrangy; Sadovskiy, Sergey; Safarik, Karel; Saha, Sumit Kumar; Sahoo, Baidyanath; Sahoo, Pragati; Sahoo, Raghunath; Sahoo, Sarita; Sahu, Pradip Kumar; Saini, Jogender; Sakai, Shingo; Saleh, Mohammad Ahmad; Sambyal, Sanjeev Singh; Samsonov, Vladimir; Sandoval, Andres; Sarkar, Amal; Sarkar, Debojit; Sarkar, Nachiketa; Sarma, Pranjal; Sas, Mike Henry Petrus; Scapparone, Eugenio; Scarlassara, Fernando; Schaefer, Brennan; Scheid, Horst Sebastian; Schiaua, Claudiu Cornel; Schicker, Rainer Martin; Schmidt, Christian Joachim; Schmidt, Hans Rudolf; Schmidt, Marten Ole; Schmidt, Martin; Schmidt, Nicolas Vincent; Schukraft, Jurgen; Schutz, Yves Roland; Schwarz, Kilian Eberhard; Schweda, Kai Oliver; Scioli, Gilda; Scomparin, Enrico; Sefcik, Michal; Seger, Janet Elizabeth; Sekiguchi, Yuko; Sekihata, Daiki; Selyuzhenkov, Ilya; Senosi, Kgotlaesele; Senyukov, Serhiy; Serradilla Rodriguez, Eulogio; Sett, Priyanka; Sevcenco, Adrian; Shabanov, Arseniy; Shabetai, Alexandre; Shahoyan, Ruben; Shaikh, Wadut; Shangaraev, Artem; Sharma, Anjali; Sharma, Ankita; Sharma, Meenakshi; Sharma, Natasha; Sheikh, Ashik Ikbal; Shigaki, Kenta; Shimomura, Maya; Shirinkin, Sergey; Shou, Qiye; Shtejer Diaz, Katherin; Sibiryak, Yury; Siddhanta, Sabyasachi; Sielewicz, Krzysztof Marek; Siemiarczuk, Teodor; Silvermyr, David Olle Rickard; Simatovic, Goran; Simonetti, Giuseppe; Singaraju, Rama Narayana; Singh, Ranbir; Singh, Randhir; Singhal, Vikas; Sarkar - Sinha, Tinku; Sitar, Branislav; Sitta, Mario; Skaali, Bernhard; Slupecki, Maciej; Smirnov, Nikolai; Snellings, Raimond; Snellman, Tomas Wilhelm; Song, Jihye; Soramel, Francesca; Sorensen, Soren Pontoppidan; Sozzi, Federica; Sputowska, Iwona Anna; Stachel, Johanna; Stan, Ionel; Stankus, Paul; Stenlund, Evert Anders; Stocco, Diego; Storetvedt, Maksim Melnik; Strmen, Peter; Alarcon Do Passo Suaide, Alexandre; Sugitate, Toru; Suire, Christophe Pierre; Suleymanov, Mais Kazim Oglu; Suljic, Miljenko; Sultanov, Rishat; Sumbera, Michal; Sumowidagdo, Suharyo; Suzuki, Ken; Swain, Sagarika; Szabo, Alexander; Szarka, Imrich; Tabassam, Uzma; Takahashi, Jun; Tambave, Ganesh Jagannath; Tanaka, Naoto; Tarhini, Mohamad; Tariq, Mohammad; Tarzila, Madalina-gabriela; Tauro, Arturo; Tejeda Munoz, Guillermo; Telesca, Adriana; Terrevoli, Cristina; Teyssier, Boris; Thakur, Dhananjaya; Thakur, Sanchari; Thomas, Deepa; Thoresen, Freja; Tieulent, Raphael Noel; Tikhonov, Anatoly; Timmins, Anthony Robert; Toia, Alberica; Topilskaya, Nataliya; Toppi, Marco; Rojas Torres, Solangel; Tripathy, Sushanta; Trogolo, Stefano; Trombetta, Giuseppe; Tropp, Lukas; Trubnikov, Victor; Trzaska, Wladyslaw Henryk; Trzcinski, Tomasz Piotr; Trzeciak, Barbara Antonina; Tsuji, Tomoya; Tumkin, Alexandr; Turrisi, Rosario; Tveter, Trine Spedstad; Ullaland, Kjetil; Umaka, Ejiro Naomi; Uras, Antonio; Usai, Gianluca; Utrobicic, Antonija; Vala, Martin; Van Hoorne, Jacobus Willem; Van Leeuwen, Marco; Vande Vyvre, Pierre; Varga, Dezso; Diozcora Vargas Trevino, Aurora; Vargyas, Marton; Varma, Raghava; Vasileiou, Maria; Vasiliev, Andrey; Vauthier, Astrid; Vazquez Doce, Oton; Vechernin, Vladimir; Veen, Annelies Marianne; Vercellin, Ermanno; Vergara Limon, Sergio; Vermunt, Luuk; Vernet, Renaud; Vertesi, Robert; Vickovic, Linda; Viinikainen, Jussi Samuli; Vilakazi, Zabulon; Villalobos Baillie, Orlando; Villatoro Tello, Abraham; Vinogradov, Alexander; Virgili, Tiziano; Vislavicius, Vytautas; Vodopyanov, Alexander; Volkl, Martin Andreas; Voloshin, Kirill; Voloshin, Sergey; Volpe, Giacomo; Von Haller, Barthelemy; Vorobyev, Ivan; Voscek, Dominik; Vranic, Danilo; Vrlakova, Janka; Wagner, Boris; Wang, Hongkai; Wang, Mengliang; Watanabe, Yosuke; Weber, Michael; Weber, Steffen Georg; Wegrzynek, Adam; Weiser, Dennis Franz; Wenzel, Sandro Christian; Wessels, Johannes Peter; Westerhoff, Uwe; Whitehead, Andile Mothegi; Wiechula, Jens; Wikne, Jon; Wilk, Grzegorz Andrzej; Wilkinson, Jeremy John; Willems, Guido Alexander; Williams, Crispin; Willsher, Emily; Windelband, Bernd Stefan; Witt, William Edward; Xu, Ran; Yalcin, Serpil; Yamakawa, Kosei; Yano, Satoshi; Yin, Zhongbao; Yokoyama, Hiroki; Yoo, In-kwon; Yoon, Jin Hee; Yurchenko, Volodymyr; Zaccolo, Valentina; Zaman, Ali; Zampolli, Chiara; Correa Zanoli, Henrique Jose; Zardoshti, Nima; Zarochentsev, Andrey; Zavada, Petr; Zavyalov, Nikolay; Zbroszczyk, Hanna Paulina; Zhalov, Mikhail; Zhang, Xiaoming; Zhang, Yonghong; Zhang, Zuman; Zhao, Chengxin; Zherebchevskii, Vladimir; Zhigareva, Natalia; Zhou, Daicui; Zhou, You; Zhou, Zhuo; Zhu, Hongsheng; Zhu, Jianhui; Zhu, Ya; Zichichi, Antonino; Zimmermann, Markus Bernhard; Zinovjev, Gennady; Zmeskal, Johann; Zou, Shuguang

2018-01-01

Inclusive J/$\\psi$ production is studied in Xe-Xe interactions at a centre-of-mass energy per nucleon pair of $\\sqrt{s_{NN}}$ = 5.44 TeV, using the ALICE detector at the CERN LHC. The J/$\\psi$ meson is reconstructed via its decay into a muon pair, in the centre-of-mass rapidity interval 2.5 < y < 4 and down to zero transverse momentum. In this Letter, the nuclear modification factors $R_{AA}$ for inclusive J/$\\psi$, measured in the centrality range 0-90% as well as in the centrality intervals 0-20% and 20-90% are presented. The $R_{AA}$ values are compared to previously published results for Pb-Pb collisions at $\\sqrt{s_{NN}}$ = 5.02 TeV and to the calculation of a transport model. A good agreement is found between Xe-Xe and Pb-Pb results as well as between data and the model.

Discharge-current characteristics in UV-preionized Kr/He, F2/He gas-mixtures and KrF excimer laser gas. Shigaisen yobi denri Kr/He, F2/He kongo kitai hoden oyobi KrF laser reiki hoden no denryu tokusei

Energy Technology Data Exchange (ETDEWEB)

Nakagawa, N.; Kawakami, H.; Yukimura, K. (Doshisha University, Kyoto (Japan))

1992-08-15

In order to study effects of Kr and F2 on discharge characteristics of KrF excimer laser gas, gap phenomena in Kr/He and F2/He gas-mixtures were observed and discharge current (I[sub d]) was measured. In the range where Kr concentration was over 10% in Kr/He gas, in which production of filamentation as well as glow discharge started, discontinuous change in I[sub d] in the second or third half cycle was observed. According to the results of experiments and model analyses, it was considered that the discontinuity of the current showed the transition point to filamentation. When F2 concentration was in the range between 0.1 and 0.3% in F2/He mixture gas, filamentation and arc with glow were observed. Sine-waveform I[sub d] ended in the first half cycle, and began to flow again after cessation or had almost constant current due to arc and others. When F2 was over 0.4%, only are discharge was observed. It was thus found that F2 has a large effect on discharge characteristics of KrF laser gas. 18 refs., 9 figs.

Beta-gamma counting system for Xe fission products

International Nuclear Information System (INIS)

Reeder, P.L.; Bowyer, T.W.; Perkins, R.W.

1998-01-01

A beta-gamma coincidence counting system has been developed for automated analysis of Xe gas samples separated from air. The Xe gas samples are contained in a cylindrical plastic scintillator cell located between two NaI(Tl) scintillation detectors. The X-ray and gamma spectra gated by coincident events in the plastic scintillator cell are recorded for each NaI(Tl) crystal. The characteristic signatures of the 131m Xe, 133g Xe, 133m Xe, and 135g Xe isotopes of interest for nuclear test-ban verification as well as the procedures and results of absolute efficiency measurements are described. A NaI(Tl) crystal with provision for 4 sample cells has been implemented for the system to be deployed in the field. Examples of data on ambient air samples in New York City obtained with the field prototype are presented. (author)

Examining Changes in Radioxenon Isotope Activity Ratios during Subsurface Transport

Science.gov (United States)

Annewandter, R.

2013-12-01

differential equations by a complementary finite volume method. The parabolic and hyperbolic problem can be solved separately using the operator-splitting method (Implicit Pressure Explicit Saturation, IMPES). The resulting system of linear equations is solved by the algebraic multigrid library SAMG, developed at the Fraunhofer Institute for Algorithms and Scientific Computing. CSMP++ is developed at Montan University of Leoben, ETH Zuerich, Imperial College London and Heriot-Watt University in Edinburgh. To date, there has been no research investigating how subsurface transport impacts isotope activity ratios. The isotopic activity ratio method can be used to discriminate between civil release or nuclear explosion sources. This study examines possible fractionation of Xe-135, Xe-133m, Xe-133, Xe-131m during barometric pumping-driven subsurface migration, which can affect surface arrival times and isotopic activity ratios. Surface arrival times for the Noble gases Kr-81, Kr-85 and Ar-39 are also calculated.

/sup 133/Xe and /sup 135/Xe interference with in vivo low-energy measurement systems

Energy Technology Data Exchange (ETDEWEB)

Cohen, N; Lo Sasso, T; Lei, W [New York Univ., NY (USA). Inst. of Environmental Medicine

1980-03-01

Fission product /sup 133/Xe and /sup 135/Xe are released to the atmosphere during normal reactor operation. With increasing numbers of nuclear power stations there will be an increase in the ambient level of these isotopes. They do not present an appreciable long-term health hazard because of their inert nature and relatively short half-lives. However, their presence in the air of a whole-body counter may interfere significantly with in vivo low-energy photon counting procedures by contributing to the background count-rate in the energy region below 300 keV. This applies particularly to lung and whole-body measurements with dual thin crystal NaI(Tl)-CsI(Tl) scintillation detectors for actinide nuclides. It is important, therefore, that gamma spectroscopists should be aware of the possible presence of /sup 133/Xe and /sup 135/Xe in the air of their whole-body counting facilities, particularly if these are near to reactors and do not have traps for removal of inert gases from their air supplies.

Difference flow and electrical conductivity measurements at the Olkiluoto site in Eurajoki, drillholes OL-KR54, OL-KR55, OL-KR55B and OL-KR47B

Energy Technology Data Exchange (ETDEWEB)

Komulainen, J.; Poellaenen, J.; Hurmerinta, E.; Ripatti, K. [Poeyry Finland Oy, Espoo (Finland)

2012-04-15

The Posiva Flow Log, Difference flow method (PFL DIFF) uses a flowmeter that incorporates a flow guide and can be used for relatively quick determinations of hydraulic conductivity and hydraulic head of fractures/fractured zones in drillholes. This report presents the principles of the method and the results of measurements carried out in drillholes OL-KR54, OL-KR55, OL-KR55B and OL-KR47B at the Olkiluoto investigation site between January 2011 and September 2011. The measuring programme employed was the same in all drillholes. The applied section lengths of the flow guide were either 2 m and 0.5 m. Flow into the drillhole or from the drillhole to the bedrock was measured within the section length. The measurements were carried out in both pumped and natural (i.e. un-pumped) conditions. The transmissivity and hydraulic head of zones were calculated from the flow and pressure results. The device used includes a sensor for single point resistance (SPR). SPR was measured in connection with the flow measurements. The electrical conductivity (EC) of fracture-specific water was measured in chosen fractures. Fractures were selected on the basis of the measured flow from fractures into the drillhole. The drillhole flow (flow along the drillhole) was measured in conjunction with drillhole EC measurements. (orig.)

Krypton and Xenon Radionuclides Monitoring in the Northwest Region of Russia

Science.gov (United States)

Dubasov, Yuri V.; Okunev, Nikolay S.

2010-05-01

Monitoring of Xe and Kr radionuclides was conducted from August 2006 to 30 July 2008 within the framework of ISTC Project #2133. Cherepovets City in Vologda Province and St. Petersburg were chosen as monitoring locations. Kr-Xe concentrate samples were obtained as a result of processing of several thousand m3 of atmospheric air. New results of 85Kr monitoring show, that for last 15 years, the 85Kr volumetric activity in the atmospheric air of the northwest region of Russia has increased approximately 50% and has achieved a level of 1.5 Bq/m3. This value correlates well with similar data for Western Europe and Japan. The xenon fraction (80-160 cm3 under STP) is adsorbed on charcoal in the ampoule, which is measured in the well of HPGe gamma detector. Minimum detectable concentration (MDC) of 133Xe for this technique is 0.008 mBq/m3, and it is the most sensitive method used today. The 133Xe concentration in the atmospheric air of Cherepovets City varied in the monitoring period ranging from 0.09 to 2.5 mBq/m3. During the period of March 2007-30 July 2008, 133Xe activity concentration in the atmospheric air of St. Petersburg changed from background values (0.2-0.3 mBq/m3) to 185 mBq/m3 and for approximately 20% of the samples 135Xe was also measured with the 135Xe/133Xe activity ratio varied within the range of 0.03-3.5.

Molecular dynamics simulations of adsorption and diffusion of Xe on bare and Xe covered Pt(111)

NARCIS (Netherlands)

Jong, de F.; Jansen, A.P.J.

1994-01-01

Molecular dynamics simulations are used to calculate adsorption probabilities and diffusion coefficients of Xe on Pt(111) and Xe/Pt(111). Experimental trends are reproduced. The adsorption mechanism is found to be the modified Kisliuk model, with the addition of direct and indirect insertion in the

The effects of pre-mix on burn in ICF capsules

International Nuclear Information System (INIS)

Wilson, D C; Kyrala, G A; Jr, J F Benage; Wysocki, F J; Gunderson, M A; Herrman, H W; Cooley, J H; Welser-Sherrill, L; Garbett, W J; Horsfield, C J; Glebov, V Y; Yaakobi, B; Roberts, S A; Frenje, J

2008-01-01

Directly driven implosions at the Omega laser have tested the effects of pre-mix of Ar, Kr, and Xe in D 2 + 3 He filled glass micro-balloons. Diagnostics included: D+D and D+T neutron yields, D+ 3 He proton yields and spectra, Doppler broadened ion temperatures, time dependent neutron and proton burn rates, and time gated, high energy filtered, X-ray images. Yields are better calculated by XSN LTE than by non-LTE. Yields with a small amount of pre-mix, atom fractions of ∼5e-3 for Ar, 2e-3 Kr, and Xe for 5e-4, are more degraded than calculated, while the measured ion temperatures are the same as without pre-mix. There is also a decrease in fuel ρr. The neutron burn histories suggest that the early yield coming before the reflected shock strikes the incoming shell is un-degraded, with yield degradation occurring afterwards. Adding 20 atm % 3 He to pure D fuel seems to produce a similar degradation. Calculated gated X-ray images agree with observed when the reflected shock strikes the incoming shell, but are smaller than observed afterward. This partially explains yield degradation and both the low fuel and whole capsule ρr's observed in secondary T+D neutrons and slowing of the D+ 3 He protons. Neither LTE on non-LTE captures the degradation by 3 He or at low pre-mix levels, nor matches the large shell radii after impact of the reflected shock

A membrane inlet mass spectrometry system for noble gases at natural abundances in gas and water samples.

Science.gov (United States)

Visser, Ate; Singleton, Michael J; Hillegonds, Darren J; Velsko, Carol A; Moran, Jean E; Esser, Bradley K

2013-11-15

Noble gases dissolved in groundwater can reveal paleotemperatures, recharge conditions, and precise travel times. The collection and analysis of noble gas samples are cumbersome, involving noble gas purification, cryogenic separation and static mass spectrometry. A quicker and more efficient sample analysis method is required for introduced tracer studies and laboratory experiments. A Noble Gas Membrane Inlet Mass Spectrometry (NG-MIMS) system was developed to measure noble gases at natural abundances in gas and water samples. The NG-MIMS system consists of a membrane inlet, a dry-ice water trap, a carbon-dioxide trap, two getters, a gate valve, a turbomolecular pump and a quadrupole mass spectrometer equipped with an electron multiplier. Noble gases isotopes (4)He, (22)Ne, (38)Ar, (84)Kr and (132)Xe are measured every 10 s. The NG-MIMS system can reproduce measurements made on a traditional noble gas mass spectrometer system with precisions of 2%, 8%, 1%, 1% and 3% for He, Ne, Ar, Kr and Xe, respectively. Noble gas concentrations measured in an artificial recharge pond were used to monitor an introduced xenon tracer and to reconstruct temperature variations to within 2 °C. Additional experiments demonstrated the capability to measure noble gases in gas and in water samples, in real time. The NG-MIMS system is capable of providing analyses sufficiently accurate and precise for introduced noble gas tracers at managed aquifer recharge facilities, groundwater fingerprinting based on excess air and noble gas recharge temperature, and field and laboratory studies investigating ebullition and diffusive exchange. Copyright © 2013 John Wiley & Sons, Ltd.

FY 1997 report on the study on cryogenic aggregate target PLD process by multi-laser excitation for using gaseous materials; 1997 nendo chosa hokokusho (kitai genryo riyo no tame no taju laser reiki ni yoru gokuteion gyoshutai target PLD process ni kansuru kenkyu)

Energy Technology Data Exchange (ETDEWEB)

NONE

1998-03-01

This paper reports the result in fiscal 1995 of the study on PLD (pulse laser deposition) thin film formation process having been made since 1993. In fiscal 1995, the effect of irradiation of excimer laser and YGA(SHG) on ablation of aggregates of N2, CH4, Ar, Kr and Xe, and the effect of time-delayed irradiation of YGA(SHG) and KrF excimer laser on ablation of N2 aggregate were studied aiming at exciting ablation by cryogenic aggregate alone. Experimental results by a newly developed multi-laser excitation experiment equipment are as follows. Ablation was not caused by KrF excimer laser irradiation, while caused by YGA(SHG) irradiation. Ablation was caused by 1mm thick N2 or CH4 aggregate alone. Kr target was the most promising among rare gas solid targets expected as seed of ablation occurrence. Multi-irradiation showed a different ablation behavior as compared with single YGA(SHG) irradiation, and in some cases, multi-irradiation not increased scattering of particles. Time-delayed multi- irradiation (YGA(SHG) excitation after excimer excitation) was effective. 23 figs., 4 tabs.

Long-term pumping test in borehole KR24 flow measurements

Energy Technology Data Exchange (ETDEWEB)

Rouhiainen, P.; Poellaenen, J. [PRG-Tec Oy, Espoo (Finland)

2005-09-15

The Difference Flow method can be used for the relatively fast determination of transmissivity and hydraulic head in fractures or fractured zones in cored boreholes. In this study, the Difference Flow method was used for hydraulic crosshole interference tests. The tests were performed in boreholes KR24 (pumped borehole) KR4, KR7, KR8, KRlO, KR14, KR22, KR22B, KR26, KR27, KR27B, KR28 and KR28B at Olkiluoto during the first and second quarters of 2004. The distance between the boreholes varies from approximately tens of meters to hundreds of meters. All the measurements were carried out in open boreholes, i.e. no packers were used. For interpretation, a normal single hole test was first performed in each borehole. Flow rates and drawdown were first measured both without pumping and with pumping the borehole under test. For practical reasons, the data set is neither complete nor similar in all tested boreholes. Connected flow to borehole KR24 was detected in all these boreholes. These flow responses were concentrated on a few zones. (orig.)

Method of separating radioactive krypton gas

International Nuclear Information System (INIS)

Kimura, Shigeru; Awada, Yoshihisa.

1975-01-01

Object: To effectively and safely separate and recover Kr-85, which requires a long storage period for attenuating radioactivity, from a mixture gas consisting of Kr-85 and Xe by a liquefaction distillation method. Structure: A mixture gas consisting of Kr and Xe is subjected to heat exchange in a cooler with Freon gas from a plurality of distillation towers for its temperature reduction from normal temperature to a lower temperature, and then it is supplied to a distillation tower. The distillation tower is held at a pressure above 15 ata, preferably around 20 ata, and a condenser provided at the top of the distillation tower is furnished with Freon as cooling medium. The rare mixture gas is distilled by liquefaction within a distillation tower, and Kr-85 is obtained from a top duct while obtaining Xe from a bottom duct. Xe after separation by liquefaction is returned to a rare mixture gas supply inlet of a liquefaction distillation means for repeated refinement in the distillation tower. (Kamimura, M.)

ETUDE STRUCTURELLE ET SPECTRES D’ABSORPTION DE Kr3+

Directory of Open Access Journals (Sweden)

A CHIKHAOUI

2001-12-01

Full Text Available Le présent travail, qui comporte deux étapes, est une étude théorique de l'agrégat de Krypton chargé une fois (Kr3+. La première étape est l'étude structurelle de Kr3+. L'hamiltonien modèle est développé dans le cadre de la méthode D.I.M (Diatomics In Molecules. Les résultats obtenus montrent que Kr3+ est linéaire. La profondeur du puits attractif De est égale  à 0.29 eV par rapport à la dissociation en Kr2+ + Kr pour une distance d'équilibre Re = 5.496 u.a. Ce résultat est en bon accord avec la valeur expérimentale qui vaut 0.27 eV. La deuxième étape est l'étude thermodynamique et spectroscopique de Kr3+. Les résultats obtenus montrent que le spectre vertical de Kr3+ linéaire comporte trois pics situés dans le domaine du visible à 625nm, 551nm et 466nm. L'analyse statistique des populations de charges atomiques montre que Kr3+ subit une isomérisation qui le ramène à une configuration de type ( Kr2+ ...Kr ou à une configuration plus probable de type  (Kr+...Kr2 .

Application of mass spectrometry to fuels and materials testing at FFTF

International Nuclear Information System (INIS)

Plucinski, C.E.; Goheen, M.W.; McCown, J.J.

1983-01-01

The Fast Flux Test Facility (FFTF) is a sodium cooled reactor operated for the Department of Energy by Westinghouse Hanford Company. In FFTF the 78 fuel pin assemblies have been tagged with a unique combination of Kr and Xe isotopes. In addition to fuel pin assemblies, other test assemblies can also be similarly tagged as in the Materials Open Test Assembly (MOTA). During power operations leaks are monitored by single channel gamma analyzers in the reactor cover gas system. When radioactive Kr and Xe isotopes are detected a gas tag sample trap (GTST) is used to take a sample of the reactor cover gas, the Kr and Xe are concentration, and isotopic analysis is obtained by mass spectrometry

Manipulation by multiple filamentation of subpicosecond TW KrF laser beam

Science.gov (United States)

Zvorykin, V. D.; Smetanin, I. V.; Ustinovskii, N. N.; Shutov, A. V.

2018-05-01

A self-focusing of TW-level subpicosecond UV KrF laser pulses in ambient air produces a few 100 randomly distributed filaments over 100-m propagation distance. A control of multiple filamentation process by a number of methods was demonstrated in the present work envisaging applications for a HV discharge guiding, remote excitation of an atmospheric air laser, MW radiation transfer by virtual plasma waveguide, as well as filamentation suppression to improve short pulse parameters in direct amplification scheme. Under the laser beam focusing, a multitude of filaments coalesced into a superfilament with highly increased intensity and plasma conductivity. A superradiant forward lasing was obtained in the superfilament around 1.07-µm wavelength of atmospheric nitrogen. A regular 2D array of a 100 superfilaments was configured over 20-m distance by Fresnel diffraction on periodic amplitude masks. Effective Kerr defocusing and a subsequent filaments suppression over 50-m distance was demonstrated in Xe due to 2-photon resonance of laser radiation with 6p state being accompanied by a narrow-angle coherent conical emission at 828-nm wavelength.

Kr-85 signatures for various plutonium production schemes

Energy Technology Data Exchange (ETDEWEB)

Stanoszek, Paul [Carl Friedrich von Weizsaecker-Centre for Science and Peace Research (Germany)

2009-07-01

Kr-85 is considered to be the best atmospheric indicator of unreported weapon-grade material production. This fact is based on the half-life of 10.76 years of Kr-85 and its chemical inactivity, which makes it even detectable after extended periods of cooling time. Kr-85 is produced as fission product during nuclear reactor operation and remains in the fuel until reprocessing starts. In order to determine the detectability of plutonium production the Kr-85 source term has to be assessed. The important issue of this presentation is the question on the minimum signal that an inspector can expect under the assumption that a proliferator minimizes his Kr-85 generation in order to circumvent a Kr-85 detection. A further assumption is that for nuclear weapon production a burn-up of typically around 2 MWd/kg is used. In addition, if clandestine plutonium production takes place, the source term might be used to estimate the amount of separated plutonium. The methodology of this study is based on a linkage between MCNPX and MATLAB. All results for actinide concentrations and Kr-85 are evaluated for different enrichments of U-235 and compared to known literature data. The Kr-85 source term per kilogram plutonium depends on the enrichments. As a result the lowest Kr-85 source term is found for depleted uranium.

μ+ charge exchange and muonium formation in low pressure gases

International Nuclear Information System (INIS)

Fleming, D.G.; Mikula, R.J.; Garner, D.M.

1982-04-01

Using the basic muon spin rotation technique, the fractions of energetic positive muons thermalizing in diamagnetic environments (fsub(μ)) or as the paramagnetic muonium atom (fsub(Mu)) have been measured in low pressure pure gases (He, Ne, Ar, Kr, Xe, H 2 , N 2 , NH 3 , and CH 4 ) as well as in several gas mixtures (Ne/Xe, Ne/Ar, Ne/NH 3 , Ne/CH 4 ). In the pure gases, the muonium fractions fsub(Mu) are generally found to be smaller than expected from analogous proton charge exchange studies, particularly in the molecular gases. This is probably due to hot atom reactions of muonium following the charge exchange regime. Comparisons with monium formation in condensed matter as well as positronium formation in gases are also presented. In the gas mixtures, the addition of only a few hundred ppm of a dopant gas, which is exothermic for muonium formation (e.g. Xe), gives rise to an fsub(Mu) characteristic of the pure dopant gas itself, demonstrating the importance of the neutralization process right down to thermal energies. In all cases, the experimental signal amplitudes are found to be strongly pressure dependent, which is interpreted in terms of the time spent by the muon as neutral muonium in the charge exchange regime: tsub(n) < 0.2 ns. This time is generally shorter in the case of molecular gases than in rare gases

Kr photoionized plasma induced by intense extreme ultraviolet pulses

Science.gov (United States)

Bartnik, A.; Wachulak, P.; Fiedorowicz, H.; Skrzeczanowski, W.

2016-04-01

Irradiation of any gas with an intense EUV (extreme ultraviolet) radiation beam can result in creation of photoionized plasmas. The parameters of such plasmas can be significantly different when compared with those of the laser produced plasmas (LPP) or discharge plasmas. In this work, the photoionized plasmas were created in a krypton gas irradiated using an LPP EUV source operating at a 10 Hz repetition rate. The Kr gas was injected into the vacuum chamber synchronously with the EUV radiation pulses. The EUV beam was focused onto a Kr gas stream using an axisymmetrical ellipsoidal collector. The resulting low temperature Kr plasmas emitted electromagnetic radiation in the wide spectral range. The emission spectra were measured either in the EUV or an optical range. The EUV spectrum was dominated by emission lines originating from Kr III and Kr IV ions, and the UV/VIS spectra were composed from Kr II and Kr I lines. The spectral lines recorded in EUV, UV, and VIS ranges were used for the construction of Boltzmann plots to be used for the estimation of the electron temperature. It was shown that for the lowest Kr III and Kr IV levels, the local thermodynamic equilibrium (LTE) conditions were not fulfilled. The electron temperature was thus estimated based on Kr II and Kr I species where the partial LTE conditions could be expected.

Preparation and dosimetry of reactor-produced Xe-125 for ventilation scintigraphy

International Nuclear Information System (INIS)

Junker, D.; Cordes, H.

1978-01-01

Xe-125 is produced in the reactor by the (n, γ)-reaction from Xe-124. The natural abundance of Xe-124, however, is only 0,1 percent. As the costs for Xe-124 enriched Xenon are considerable, natural Xenon is activated in the epithermal energy region. In contrast to the other stable isotopes of Xenon, Xe-124 shows a large resonance cross section in this energy region. The main activation product is Xe-125. In addition, a few nuclides (e.g. Xe-125m, Xe-127m, Xe-137) are produced, which due to their short half lives give no contribution to radiation dose. Radiocontaminants originating from parent-daughter decay (e.g. Cs-135 and Cs-137) are separated by filtration of the gas. I-125 produced by the decay of Xe-125 is removed by filtering of the gas before administration to the patient. Typical yields of a sample capsule are 20 to 30 mCi Xe-125 after irradiation of 4 hours in an epithermal flux of approximately 2.10 -11 s -1 cm -2 . The residual contaminants contributing to the radiation dose are Xe-135 and Xe-129m. Depending on the irradiation time they amount to a few percent of the total activity. Using Xe-125 for lung ventilation studies results in considerable reduction of radiation dose as compared to Xe-133. An additional advantage is the better tissue penetration of Xe-125 (γ-energies at 188 keV (55%) and 243 keV (29%)) permitting the reduction of the dose for a study. The daughter nuclide I-125 generated during the study causes only a few mrem of radiation dose if the thyroid is blocked. Altogether Xe-125 as compared to Xe-133 offers more suitable γ-energies for lung ventilation studies and in addition a reduced radiation dose to the patient. (author)

Centrality determination using the Glauber model in Xe-Xe collisions at $\\sqrt{s_{\\rm NN}} = 5.44$ TeV

CERN Document Server

2018-01-01

This document describes the methods used by the ALICE Collaboration for determining the centrality of Xe-Xe collisions at $\\sqrt{s_{\\rm NN}} = 5.44$ TeV at the LHC within the Glauber model. The half-density radius $R$ and the diffusivity $a$ describing the Xe-129 nucleus with a 2-parameter Fermi distribution have been derived from a recent electron scattering measurement for the Xe-132 nucleus. The deformation parameter $\\beta$ has been derived by an interpolation between measured deformation parameters for the even-$A$ Xe isotopes. The inelastic nucleon-nucleon cross-section at $\\sqrt{s_{\\rm NN}} = 5.44$ TeV has been estimated by interpolation of pp data at different center-of-mass energies. The particle multiplicity per nucleon-nucleon collision has been parameterized by a negative binomial distribution (NBD) and a number of independently emitting sources (ancestors) given by a linear combination of $N_{\\rm part}$ and $N_{\\rm coll}$. The NBD parameters $\\mu$ and $k$ and the ancestor parameter $f$ are then...

The state of physically adsorbed substances in microporous adsorbents

International Nuclear Information System (INIS)

Fomkin, A.A.

1987-01-01

Xe, Kr, Ar, CF 3 Cl, CH 4 adsorption in NaX microporous zeolite of 0.98 Na 2 OxAl 2 O 3 x2.36SiO 2 x0.02H 2 O is studied. Some properties of adsorbates (density, coefficients of expansion, enthalpy, heat capacity) are determined and discussed. The adsorbate in the microporous adsorbent is shown to be a particular state of a substance. Liniarity of adsorption isosteres and sharp changes during isosteric heat capacity of the adsorbate points to the fact that in microporous adsorbents phase transformations of the second type are possible

Systematics of quasi-elastic processes induced by heavy ions

International Nuclear Information System (INIS)

Baltz, A.J.

1976-01-01

An attempt is made to delineate the areas in the systematics of quasi-elastic processes induced by heavy ions that are well described theoretically from the specific features that seem not to be understood. One- and two-particle transfer reactions are considered. A general systematic seen in transfer angular distribution data and theory, some successes and failures of the DWBA and coupled-channels theories in describing heavy-ion-reaction data, and the specific example 232 Th( 40 Ar,K) and implications for deep inelastic reactions with even heavier projectiles such as Kr and Xe are considered

Modeling the cathode region of noble gas mixture discharges using Monte Carlo simulation

International Nuclear Information System (INIS)

Donko, Z.; Janossy, M.

1992-10-01

A model of the cathode dark space of DC glow discharges was developed in order to study the effects caused by mixing small amounts (≤2%) of other noble gases (Ne, Ar, Kr and Xe) to He. The motion of charged particles was described by Monte Carlo simulation. Several discharge parameters (electron and ion energy distribution functions, electron and ion current densities, reduced ionization coefficients, and current density-voltage characteristics) were obtained. Small amounts of admixtures were found to modify significantly the discharge parameters. Current density-voltage characteristics obtained from the model showed good agreement with experimental data. (author) 40 refs.; 14 figs

Influence of heavy ion implantation on the microhardness of lif

CERN Document Server

Abu-Alazm, S M

2003-01-01

The paper presented microhardness measurements for pure lithium fluoride (LiF) implanted with Ar, Kr and Xe at doses ranged from 10 sup 9 up to 10 sup 1 2 ion/cm sup 2. Measurements were also performed for the microhardness after irradiation by electron and gamma rays. The data exhibited a large increase of microhardness of LiF using heavy ions in comparison with the unimplanted and irradiated samples with electrons and gamma rays. The influence of annealing the samples on the microhardness is also studied. The obtained results were interpreted according to the formation of F-centers in LiF.

Dipole, quadrupole, and octupole terms in the long-range hyperfine frequency shift for hydrogen in the presence of inert gases

International Nuclear Information System (INIS)

Greenwood, W.G.; Tang, K.T.

1987-01-01

The R -6 , R -8 , and R -10 terms in the long-range expansion for the hyperfine frequency shift are calculated for hydrogen in the presence of He, Ne, Ar, Kr, and Xe. The R -6 terms are based on the dipole oscillator strength sums. For helium, the R -8 and R -10 terms are based on quadrupole and octupole oscillator strength sums. For the heavier inert gases, the results for the R -8 and R -10 terms are obtained from the sum rules and the static polarizabilities. Upper bounds are also determined for the R -8 and R -10 terms

Many-electron model for multiple ionization in atomic collisions

International Nuclear Information System (INIS)

Archubi, C D; Montanari, C C; Miraglia, J E

2007-01-01

We have developed a many-electron model for multiple ionization of heavy atoms bombarded by bare ions. It is based on the transport equation for an ion in an inhomogeneous electronic density. Ionization probabilities are obtained by employing the shell-to-shell local plasma approximation with the Levine and Louie dielectric function to take into account the binding energy of each shell. Post-collisional contributions due to Auger-like processes are taken into account by employing recent photoemission data. Results for single-to-quadruple ionization of Ne, Ar, Kr and Xe by protons are presented showing a very good agreement with experimental data

Many-electron model for multiple ionization in atomic collisions

Energy Technology Data Exchange (ETDEWEB)

Archubi, C D [Instituto de AstronomIa y Fisica del Espacio, Casilla de Correo 67, Sucursal 28 (C1428EGA) Buenos Aires (Argentina); Montanari, C C [Instituto de AstronomIa y Fisica del Espacio, Casilla de Correo 67, Sucursal 28 (C1428EGA) Buenos Aires (Argentina); Miraglia, J E [Instituto de AstronomIa y Fisica del Espacio, Casilla de Correo 67, Sucursal 28 (C1428EGA) Buenos Aires (Argentina)

2007-03-14

We have developed a many-electron model for multiple ionization of heavy atoms bombarded by bare ions. It is based on the transport equation for an ion in an inhomogeneous electronic density. Ionization probabilities are obtained by employing the shell-to-shell local plasma approximation with the Levine and Louie dielectric function to take into account the binding energy of each shell. Post-collisional contributions due to Auger-like processes are taken into account by employing recent photoemission data. Results for single-to-quadruple ionization of Ne, Ar, Kr and Xe by protons are presented showing a very good agreement with experimental data.

Absolute cross sections for the multielectron processes in 15 keV I10++rare gas collisions

International Nuclear Information System (INIS)

Nakamura, N.; Currell, F.J.; Danjo, A.; Kimura, M.; Matsumoto, A.; Ohtani, S.; Sakaue, H.A.; Sakurai, M.; Tawara, H.; Watanabe, H.; Yamada, I.; Yoshino, M.

1995-01-01

We have experimentally determined the absolute cross sections for total charge transfer (σ q ), j electron transfer (σ j q ), i electron capture (σ q,q-i ) and each reaction process (σ j q,q-i ) in 15 keV I 10+ -Ne, Ar, Kr and Xe collisions. The branching ratios were determined by the coincidence measurements between charge changing projectile and recoil ions. The electron capture cross sections were measured by the initial growth rate method. The experimental results for total and j electron transfer cross sections were compared with the predictions of the extended classical over-barrier model (ECBM). (orig.)

Quenching reactions of electronically excited atoms

International Nuclear Information System (INIS)

Setser, D.W.

2001-01-01

The two-body, thermal quenching reactions of electronically excited atoms are reviewed using excited states of Ar, Kr, and Xe atoms as examples. State-specific interstate relaxation and excitation-transfer reactions with atomic colliders are discussed first. These results then are used to discuss quenching reactions of excited-state atoms with diatomic and polyatomic molecules, the latter have large cross sections, and the reactions can proceed by excitation transfer and by reactive quenching. Excited states of molecules are not considered; however, a table of quenching rate constants is given for six excited-state molecules in an appendix

Xe-129 NMR chemical shift in Xe@C-60 calculated at experimental conditions: Essential role of the relativity, dynamics, and explicit solvent

Czech Academy of Sciences Publication Activity Database

Standara, Stanislav; Kulhánek, P.; Marek, R.; Straka, Michal

2013-01-01

Roč. 34, č. 22 (2013), s. 1890-1898 ISSN 0192-8651 R&D Projects: GA ČR GA203/09/2037; GA ČR GA13-03978S Grant - others:7th European Community Framework Program(XE) FP7-286154; CEITEC-Central European Institute of Technology (European Regional Development)(XE) CZ.1.05/1.1.00/02.0068; Operational Program Research and Development for Innovations(XE) CZ.1.05/3.2.00/08.0144 Institutional support: RVO:61388963 Keywords : Xe-129 NMR * Xe@C-60 * dynamical averaging * explicit solvent * relativistic effects Subject RIV: CF - Physical ; Theoretical Chemistry Impact factor: 3.601, year: 2013

Production of pure 133mXe for CTBTO

Science.gov (United States)

Peräjärvi, K.; Eronen, T.; Gorelov, D.; Hakala, J.; Jokinen, A.; Kettunen, H.; Kolhinen, V.; Laitinen, M.; Moore, I. D.; Penttilä, H.; Rissanen, J.; Saastamoinen, A.; Toivonen, H.; Turunen, J.; Äystö, J.

2014-01-01

Underground nuclear weapon detonations release gaseous species into the atmosphere. The most interesting isotopes/isomers from the detection point of view are 131mXe, 133mXe, 133Xe and 135Xe. We have developed a method that employs high-precision Penning trap mass spectrometry at the JYFLTRAP facility, the University of Jyväskylä, to produce pure calibration samples of these isotopes/isomers. Among developments this work required a new mass resolution record of a few parts-per-million. Here the status and future plans of the project are reviewed.

The excited states of 79Kr

International Nuclear Information System (INIS)

Liptak, J.; Kristiak, J.; Kristiakova, K.

1977-01-01

The β + -decay of 79 Rb has been studied with Ge(Li) detectors in single and coincidence modes. The half-life of the 147.06 keV level in 79 Kr has been determined to be (78+-6) ns. The relative electron intensities of seventeen transitions have been measured with a magnetic Si(Li) spectrometer. The internal conversion coefficients have been determined. The transition multipolarities have been deduced. The spin-parity assignments have been made for excited states of 79 Kr and a β-decaying sta 79 Rb(5/2 + ). The structure of excited states in 79 Kr is discussed in the framework of the Alaga and Coriolis coupling models. It is shown that the properties of some levels in 79 Kr can be explained by the existence of relatively pure rotational bands

Fission gas release in LWR fuel measured during nuclear operation

International Nuclear Information System (INIS)

Appelhans, A.D.; Skattum, E.; Osetek, D.J.

1980-01-01

A series of fuel behavior experiments are being conducted in the Heavy Boiling Water Reactor in Halden, Norway, to measure the release of Xe, Kr, and I fission products from typical light water reactor design fuel pellets. Helium gas is used to sweep the Xe and Kr fission gases out of two of the Instrumented Fuel Assembly 430 fuel rods and to a gamma spectrometer. The measurements of Xe and Kr are made during nuclear operation at steady state power, and for 135 I following reactor scram. The first experiments were conducted at a burnup of 3000 MWd/t UO 2 , at bulk average fuel temperatures of approx. 850 K and approx. 23 kW/m rod power. The measured release-to-birth ratios (R/B) of Xe and Kr are of the same magnitude as those observed in small UO 2 specimen experiments, when normalized to the estimated fuel surface-to-volume ratio. Preliminary analysis indicates that the release-to-birth ratios can be calculated, using diffusion coefficients determined from small specimen data, to within a factor of approx. 2 for the IFA-430 fuel. The release rate of 135 I is shown to be approximately equal to that of 135 Xe

Performance of a 200-J KrF laser amplifier for laser fusion research

International Nuclear Information System (INIS)

Owadano, Y.; Okuda, I.; Tanimoto, M.; Kasai, T.; Matsumoto, Y.; Yaoita, A.; Nemoto, F.; Komeiji, S.; Yano, M.

1986-01-01

An e-beam-pumped KrF laser has been developed as a middle-stage amplifier of a 1-kJ system for laser fusion research. The laser consists of one Marx generator (1MV, 11kJ), two PFLs (4.6 Ω, 100ns) with laser triggered output switches, two e-beam diodes (10 X 60 cm/sup 2/), and a laser cell (20- X 20- X 60-cm/sup 3/ active volume). Two e-beams are injected into the cell through carbon-sprayed Kapton anode and pressure foils. Up to now, a 120-J (70-ns) laser pulse has been generated with a 90% output coupling flat-flat resonator at 80% voltage operation. Overall efficiency is 1.5% in this case. A series of experiments has been performed with the laser to measure gain characteristics of a Kr-rich mixture, which is predicted to be more efficient than a normal Ar mixture in a high-laser-intensity region (>10 MW cm/sup -2/). An injection-locked oscillator mode was used to obtain a well-defined high-intensity laser beam, and a saturated intracavity intensity was measured

Kinetic studies following state-selective laser excitation: Annual performance report for the period March 15, 1987-March 14, 1988

International Nuclear Information System (INIS)

Keto, J.W.

1987-11-01

The objective of this contract is the study of state-to-state, electronic energy transfer reactions following two-photon laser excitation. We have specifically been studying reactions of Xe 5p 5 6p because of their relevance to the XeCl excimer laser. We are studying deactivation reactions in collisions with heavy atoms such as Ar, Kr, and Xe and reactive collisions with chlorides. The reactants are excited by multiphoton laser absorption. Product channels are observed by their fluorescence, or in experiments in the coming months by laser induced fluorescence using a second color laser. Reaction rates are measured by observing the time dependent decay of signals from reactant and product channels. In addition we measure interaction potentials of the reactants by laser spectroscopy where the laser induced fluorescence or ionization is measured as a function of laser wavelength (excitation spectra) or by measuring fluorescence spectra at fixed laser frequencies with monochromators. The spectra are obtained in the form of either lineshapes or individual lines from rovibrational transitions of bound states. 4 figs

Kinetic studies following state-selective laser excitation: Progress report, March 15, 1988--March 14, 1989

International Nuclear Information System (INIS)

Keto, J.W.

1988-11-01

The objective of this contract is the study of state-to-state, electronic energy transfer reactions following two-photon laser excitation. We have chosen to study reactions of Xe 5p 5 np because of their relevance to the XeCl excimer laser. We are studying deactivation reactions in collisions with heavy atoms such as Ar, Kr, and Xe and reactive collisions with chlorides. The reactants are excited by multiphoton laser absorption. Product channels are observed by their fluorescence, or by laser induced fluorescence using a second color laser. Reaction rates are measured by observing the time dependent decay of signals from reactant and product channels. In addition we measure interaction potentials of the reactants by laser spectroscopy where the laser induced fluorescence or ionization is measured as a function of laser wavelength (excitation spectra) or by measuring fluorescence spectra at fixed laser frequencies with monochromators. The spectra are obtained in the form of either lineshapes or individual lines from rovibrational transitions of bound states. 11 refs. 4 figs., 3 tabs

High spin {gamma}-ray spectroscopy of {sup 121,122}Xe

Energy Technology Data Exchange (ETDEWEB)

Timmers, H [Liverpool Univ. (United Kingdom). Oliver Lodge Lab.; [Department of Physics, SUNY at Stony Brook, NY (United States); Riley, M A; Hanna, F; Mullins, S M; Sharpey-Schafer, J F [Liverpool Univ. (United Kingdom). Oliver Lodge Lab.; Hughes, J R; Fossan, D B; Liang, Y; Ma, R; Xu, N [Department of Physics, SUNY at Stony Brook, NY (United States); Simpson, J; Bentley, M A [Daresbury Lab. (United Kingdom); Bengtsson, T [Lund Univ. (Sweden). Dept. of Mathematical Physics; Wyss, R [Institute for Heavy Ion Research, Oak Ridge, TN (United States)

1992-08-01

High-spin states have been populated in {sup 121,122}Xe using the reactions {sup 108}Pd({sup 16}O,3n){sup 121}Xe at 65 MeV and {sup 96}Zr({sup 30}Si,4n/5n){sup 122}Xe/{sup 121}Xe at 135 MeV. Coincident {gamma} rays following the neutron evaporation were detected by six Compton-suppressed Ge detectors and the TESSA3 array respectively. The level structure of {sup 121}Xe and {sup 122}Xe has been extended up to 47/2 {Dirac_h} and 32 {Dirac_h} respectively. In {sup 121}Xe a coupled band was found feeding the 19/2{sup -} level. In {sup 122}Xe several decays are suggested to be a sequence of stretched E2 quadrupole transitions connecting states of positive parity. While in {sup 121}Xe this phenomenon was not observed, at high spin a phase transition from prolate collective rotation to oblate single particle excitation was detected in {sup 122}Xe. For the new, probably positive parity side band in{sup 122}Xe a four quasi-neutron or a two quasi-proton configuration of h{sub 11/2} quasi-nucleons might be considered. The positive parity high spin structure in {sup 122}Xe contains three I{sup {pi}} = 22{sup +} states of different character. This is predicted by TRS (total Routhian surface) calculations, which identify these states as two shapes with predominantly prolate collective characteristic and the third as an oblate single particle configuration. 12 refs., 3 figs.

Formation of (Xe2H)* centers in solid Xe via recombination: nonstationary luminescence and 'internal electron emission'

International Nuclear Information System (INIS)

Savchenko, E.V.; Khyzhniy, I.V.; Uyutov, S.A.; Gumenchuk, G.B.; Ponomarev, A.N.; Bondybey, V.E.; Beyer, M.K.

2010-01-01

The formation of excimers (Xe 2 H) * in solid Xe doped with molecular hydrogen under electron beam is studied using the original two-stage technique of nonstationary (NS) cathodoluminescence (CL) in combination with the current activation spectroscopy method - thermally stimulated exoelectron emission (TSEE). Charged species were generated using a high-density electron beam. The species produced were then probed with a low density beam on gradual sample heating. The near UV emission of the (Xe 2 H) * was used to monitor the neutralization process. It is found that the temperature behavior of the NS CL band of (Xe 2 H) * clearly correlates with the yield of TSEE measured after identical pre-irradiation of the sample. The fingerprints of the thermally stimulated detrapping of electrons - 'internal electron emission' in the spectrum of NS CL point to the essential role of neutralization reaction in the stability of the proton solvated by rare-gas atoms.

Ne beam-Kr target interaction

Energy Technology Data Exchange (ETDEWEB)

Fortov, V E; Kostin, V V; Vorob` ev, V S [Russian Academy of Sciences, Moscow (Russian Federation). High Energy Density Research Center; Kulish, M I; Mintsev, V B [Russian Academy of Sciences, Chernogolovka (Russian Federation). Inst. of Chemical Physics; Hoffman, [Gesellschaft fuer Schwerionenforschung, Darmstadt (Germany)

1997-12-31

Energetic heavy ions of Ne - crystal Kr target interaction is investigated both experimentally and with the help of a 2-D computer code. The dynamics of the target matter heating, expansion, and destruction are described. A new equation of state for Kr was obtained and tested within a wide range of parameters. (author). 2 figs., 10 refs.

Modification of the Xe 4d giant resonance by the C60 shell in molecular Xe at C60

International Nuclear Information System (INIS)

Amusia, M. Ya.; Baltenkov, A. S.; Chernysheva, L. V.; Felfli, Z.; Msezane, A. Z.

2006-01-01

It is demonstrated that in photoabsorption of the 4d 10 subshell of a Xe atom in molecular Xe at C 60 , the 4d giant resonance that characterizes the isolated Xe atom is distorted significantly. The reflection of photoelectron waves by the C 60 shell leads to profound oscillations in the photoionization cross section such that the Xe giant resonance is transformed into four strong peaks. Similarly, the angular anisotropy parameters, both dipole and nondipole, are also modified. The method of calculation is based on the approximation of the C 60 shell by an infinitely thin bubble potential that leaves the sum rule for the 4d-electrons almost unaffected, but noticeably modifies the dipole polarizability of the 4d-shell

¹³⁶ Xe enrichment through cryogenic distillation

Energy Technology Data Exchange (ETDEWEB)

Back, Henning O.; Bottenus, Daniel R.; Clayton, Christopher K.; Stephenson, David E.; TeGrotenhuis, Ward E.

2017-09-01

The next generation of 136Xe neutrinoless double beta decay experiments will require on the order of 5 tons of enriched 136Xe. By estimating the relative volatilities of the xenon isotopes and using standard chemical engineering techniques we explore the feasibility of using cryogenic distillation to produce 5 tons of 80% enriched 136Xe in 5-6 years. With current state-of-the-art distillation column packing materials we can estimate the total height of a traditional cryogenic distillation column. We also, report on how Micro Channel Distillation may reduce the overall size of a distillation system for 136Xe production.

Recoil distance lifetime measurements in 122,124Xe

Science.gov (United States)

Govil, I. M.; Kumar, A.; Iyer, H.; Li, H.; Garg, U.; Ghugre, S. S.; Johnson, T.; Kaczarowski, R.; Kharraja, B.; Naguleswaran, S.; Walpe, J. C.

1998-02-01

Lifetimes of the lower-excited states in 122,124Xe are measured using the recoil-distance Doppler-shift technique. The reactions 110Pd(16O,4n)122Xe and 110Pd(18O,4n)124Xe at a beam energy of 66 MeV were used for this experiment. The lifetimes of the 2+, 4+, 6+, and 8+ states of the ground state band were extracted using the computer code LIFETIME including the corrections due to the side feeding and the nuclear deorientation effects. The lifetime of the 2+ state in 122Xe agrees with the recoil distance method (RDM) measurements but for the 124Xe it does not agree with the RDM measurements but agrees with the Coulomb-excitation experiment. The measured B(E2) values for both the nuclei are compared with the standard algebraic and the multishell models.

Energy of solution of rare gases in metals; Energie de dissolution des gaz rares dans les metaux

Energy Technology Data Exchange (ETDEWEB)

Blin, J. [Commissariat a l' Energie Atomique, Saclay (France).Centre d' Etudes Nucleaires

1959-07-01

In order to calculate the energy of solution of rare gases in metals, a method which has given good results in the case of solid solutions in metals has been applied. Nevertheless, it was necessary for this, to know the compressibility of gases under conditions which are not feasible in a laboratory. H. Jensen has studied this compressibility in a precise way for the rare gases Ar, Kr, Xe. It has thus been possible to calculate the energy of solution of these gases in different metals. These calculations have been carried out most thoroughly for the case of uranium. (author) [French] Nous avons applique au calcul de l'energie de dissolution des gaz rares dans les metaux, une methode qui a donne de bons resultats dans le cas des solutions solides metalliques. Il fallait pour cela connaitre la compressibilite des gaz rares dans des conditions impossibles a realiser en laboratoire. Cette compressibilite a ete etudiee par H. Jensen de facon precise pour les gaz rares A, Kr, Xe. Nous avons pu, de ce fait, calculer les energies de dissolution de ces gaz dans les differents metaux. Les calculs ont ete faits plus completement dans le cas de l'uranium. (auteur)

Energy of solution of rare gases in metals; Energie de dissolution des gaz rares dans les metaux

Energy Technology Data Exchange (ETDEWEB)

Blin, J [Commissariat a l' Energie Atomique, Saclay (France).Centre d' Etudes Nucleaires

1959-07-01

In order to calculate the energy of solution of rare gases in metals, a method which has given good results in the case of solid solutions in metals has been applied. Nevertheless, it was necessary for this, to know the compressibility of gases under conditions which are not feasible in a laboratory. H. Jensen has studied this compressibility in a precise way for the rare gases Ar, Kr, Xe. It has thus been possible to calculate the energy of solution of these gases in different metals. These calculations have been carried out most thoroughly for the case of uranium. (author) [French] Nous avons applique au calcul de l'energie de dissolution des gaz rares dans les metaux, une methode qui a donne de bons resultats dans le cas des solutions solides metalliques. Il fallait pour cela connaitre la compressibilite des gaz rares dans des conditions impossibles a realiser en laboratoire. Cette compressibilite a ete etudiee par H. Jensen de facon precise pour les gaz rares A, Kr, Xe. Nous avons pu, de ce fait, calculer les energies de dissolution de ces gaz dans les differents metaux. Les calculs ont ete faits plus completement dans le cas de l'uranium. (auteur)

Analysis of a multicomponent gas absorption system with carrier gas coabsorption

International Nuclear Information System (INIS)

Merriman, J.R.

1975-03-01

Conventional integrated versions of the packed gas absorber design equations do not account for significant coabsorption of the carrier gas along with the dilute transferring species. These equations, as a result, also neglect the relationship between dilute component transfer and carrier gas coabsorption. In the absorption of Kr and Xe from various carrier gases, using CCl 2 F 2 as the process solvent, carrier coabsorption is substantial. Consequently, a design package was developed to deal with multicomponent gas absorption in systems characterized by carrier gas coabsorption. Developed within the general film theory framework, the basic feature of this design approach is a view of dilute component mass-transfer as a conventional diffusive transfer superimposed on a net flux caused by carrier absorption. Other supporting elements of the design package include predictive techniques for various fluid properties, estimating procedures for carrier gas equilibrium constants, and correlations for carrier gas and dilute gas mass-transfer coefficients. When applied to systems using CCl 2 F 2 as the solvent; He, N 2 , air, or Ar as the carrier gas; and Kr or Xe as the dilute gas; the design approach gave good results, even when extended to conditions well beyond those of its development. (U.S.)

Completion of Kr-81 and Kr-85 Analysis Development for Hydrogeology and Testing its Validity by Assessing Aquifer Recharge Rates

International Nuclear Information System (INIS)

Thonnard, Norbert

2007-01-01

The overall objective was to complete the development of a RIMS-based analytical technique to determine the concentration of the rare krypton radioisotopes, 81Kr and 85Kr, in samples of interest to the geoscience and planetary science community The key to RIMS is the use of tunable lasers to selectively and efficiently excite by resonant photon absorption atomic states unique to the chosen element. Ionization of the specified element can then occur while excluding all other constituents of the sample, bringing detection limits down to the single-atom level. Combining RIMS with several steps of isotopic enrichment makes detection of a rare isotope, such as 81Kr, feasible. A complete process for groundwater samples consists of starting with (1) collecting the groundwater sample, (2) degassing the water sample, (3) separating Kr from the recovered gases, (4 and 5) two isotopic enrichments reducing interfering isotopes by >109, and (6) detecting the rare krypton isotope using RIMS in a time-of-flight system. Required water sample size is 20 liters for 81Kr and 10 to 3 liters for 85Kr. Weak links in the above steps were to be identified and rectified. Most of the troublesome issues were resolved, but unfortunately, two key difficulties could not be resolved with the available resources, so the overall, final goal of completing a suite of measurements was not achieved. In spite of this, valuable collaborations were established to demonstrate the value of 81Kr and 85Kr measurements in two critical applications, the future site of a nuclear waste repository, where high efficiency 81Kr measurements would allow groundwater dating of low-yield formations, and a multi-method analysis of potential contamination inflow into a large municipal water system, where the simplicity of interpretation of 85Kr measurements could become a valuable future interpretive tool. Therefore, samples were collected anyway, and processing started using the working parts of the method, so that

Asymmetric output profile of Xe Laser

NARCIS (Netherlands)

Blok, F.J.; Rubin, P.L.; Verschuur, Jeroen W.J.; Witteman, W.J.

2001-01-01

A new set of asymmetric modes was recently revealed in a Xe slab laser with pronounced lens effects originating from gas heating in the discharge. The appearance of these modes is a threshold effect. Their domain of existence in the Xe laser is discussed. It is shown that mode competition can result