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Sample records for hyperfine level splitting

  1. Measurement of the hyperfine splitting of the 6S$_{1/2}$ level in rubidium

    CERN Document Server

    Galvan, A Perez; Orozco, L A

    2008-01-01

    We present a measurement of the hyperfine splitting of the 6S$_{1/2}$ excited level of rubidium using two photon absorption spectroscopy in a glass cell. The values we obtain for the magnetic dipole constant A are 239.18(03) MHz and 807.66(08) MHz for $^{85}$Rb and $^{87}$Rb, respectively. The combination of the magnetic moments of the two isotopes and our measurements show a hyperfine anomaly in this atomic excited state. The observed hyperfine anomaly difference has a value of $_{87}\\delta_{85}=-0.0036(2)$ due to the finite distribution of nuclear magnetization, the Bohr-Weisskopf effect.

  2. 2S Hyperfine splitting of muonic hydrogen

    CERN Document Server

    Martynenko, A P

    2004-01-01

    Corrections of orders alpha^5, alpha^6 are calculated in the hyperfine splitting of the 2S state in the muonic hydrogen. The nuclear structure effects are taken into account in the one- and two-loop Feynman amplitudes by means of the proton electromagnetic form factors. Total numerical value of the 2S state hyperfine splitting 22.8148 meV in the (\\mu p) can be considered as reliable estimation for the corresponding experiment with the accuracy 10^{-5}. The value of the Sternheim's hyperfine splitting interval [8\\Delta E^{HFS}(2S)-\\Delta E^{HFS}(1S)] is obtained with the accuracy 10^{-6}.

  3. Hyperfine splitting in lithium-like bismuth

    Energy Technology Data Exchange (ETDEWEB)

    Lochmann, Matthias; Froemmgen, Nadja; Hammen, Michael; Will, Elisa [Universitaet Mainz (Germany); Andelkovic, Zoran; Kuehl, Thomas; Litvinov, Yuri; Winters, Danyal; Sanchez, Rodolfo [GSI Helmholtzzentrum, Darmstadt (Germany); Botermann, Benjamin; Noertershaeuser, Wilfried [Technische Universitaet Darmstadt (Germany); Bussmann, Michael [Helmholtzzentrum Dresden-Rossendorf (Germany); Dax, Andreas [CERN, Genf (Switzerland); Hannen, Volker; Joehren, Raphael; Vollbrecht, Jonas; Weinheimer, Christian [Universitaet Muenster (Germany); Geppert, Christopher [Universitaet Mainz (Germany); GSI Helmholtzzentrum, Darmstadt (Germany); Stoehlker, Thomas [GSI Helmholtzzentrum, Darmstadt (Germany); Universitaet Heidelberg (Germany); Thompson, Richard [Imperial College, London (United Kingdom); Volotka, Andrey [Technische Universitaet Dresden (Germany); Wen, Weiqiang [IMP Lanzhou (China)

    2013-07-01

    High-precision measurements of the hyperfine splitting values on Li- and H-like bismuth ions, combined with precise atomic structure calculations allow us to test QED-effects in the regime of the strongest magnetic fields that are available in the laboratory. Performing laser spectroscopy at the experimental storage ring (ESR) at GSI Darmstadt, we have now succeeded in measuring the hyperfine splitting in Li-like bismuth. Probing this transition has not been easy because of its extremely low fluorescence rate. Details about this challenging experiment will be given and the achieved experimental accuracy are presented.

  4. Hyperfine splitting in hydrogen with form factors

    CERN Document Server

    Daza, F Garcia; Nowakowski, M

    2010-01-01

    Proton structure corrections to the hyperfine splittings in hydrogen are evaluated using the Breit potential with electromagnetic form factors. In contrast to other methods, several new features emerge: the Breit potential with $q^2$-dependent form factors is just an extension of the standard Breit equation which gives the hyperfine Hamiltonian. Order $\\alpha^5$ corrections are obtained from a one-photon exchange amplitude and time-independent perturbation theory. Structure corrections to $D_{21} = 8 E^{2S}_{hfs} - E^{1S}_{hfs}$ start at order $\\alpha^6$. QED corrections are comparable to structure corrections which must be evaluated ab initio.

  5. Towards a test of QED in investigations of the hyperfine splitting in heavy ions.

    Science.gov (United States)

    Shabaev, V M; Artemyev, A N; Yerokhin, V A; Zherebtsov, O M; Soff, G

    2001-04-30

    A possibility for investigations of quantum electrodynamics (QED) in experiments on the hyperfine splitting in heavy ions is examined. It is found that QED effects can be probed on the level of a few percent in a specific difference of the hyperfine splitting values in hydrogenlike and lithiumlike bismuth. This could provide a test of QED in the strongest electric field available at present for experimental study.

  6. Ground state hyperfine splitting of high Z hydrogenlike ions

    CERN Document Server

    Shabaev, V M; Kühl, T; Artemiev, A N; Yerokhin, V A

    1997-01-01

    The ground state hyperfine splitting values of high Z hydrogenlike ions are calculated. The relativistic, nuclear and QED corrections are taken into account. The nuclear magnetization distribution correction (the Bohr-Weisskopf effect) is evaluated within the single particle model with the g_{S}-factor chosen to yield the observed nuclear moment. An additional contribution caused by the nuclear spin-orbit interaction is included in the calculation of the Bohr-Weisskopf effect. It is found that the theoretical value of the wavelength of the transition between the hyperfine splitting components in ^{165}Ho^{66+} is in good agreement with experiment.

  7. Hyperfine meson splittings: chiral symmetry versus transverse gluon exchange

    CERN Document Server

    Llanes-Estrada, Felipe J; Swanson, Eric S; Szczepaniak, Adam P; Llanes-Estrada, Felipe J.; Cotanch, Stephen R.; Szczepaniak, Adam P.; Swanson, Eric S.

    2004-01-01

    Meson spin splittings are examined within an effective Coulomb gauge QCD Hamiltonian incorporating chiral symmetry and a transverse hyperfine interaction necessary for heavy quarks. For light and heavy quarkonium systems the pseudoscalar-vector meson spectrum is generated by approximate BCS-RPA diagonalizations. This relativistic formulation includes both $S$ and $D$ waves for the vector mesons which generates a set of coupled integral equations. A smooth transition from the heavy to the light quark regime is found with chiral symmetry dominating the $\\pi$-$\\rho$ mass difference. A good, consistent description of the observed meson spin splittings and chiral quantities, such as the quark condensate and the $\\pi$ mass, is obtained. Similar comparisons with TDA diagonalizations, which violate chiral symmetry, are deficient for light pseudoscalar mesons indicating the need to simultaneously include both chiral symmetry and a hyperfine interaction. The $\\eta_b$ mass is predicted to be around 9400 MeV consistent w...

  8. Single pion contribution to the hyperfine splitting in muonic hydrogen

    CERN Document Server

    Huong, Nguyen Thu; Moussallam, Bachir

    2015-01-01

    We consider the simple one-pion exchange (Yukawa potential) contribution to the 2S hyperfine splitting in muonic hydrogen which had, until recently, been disregarded. We evaluate the relevant vertex amplitudes, in particular $\\pi^0\\mu^+\\mu^-$, combining low energy chiral expansions together with experimental data on $\\pi^0$ and $\\eta$ decays. The result for the 2S HFS is found to be small but not irrelevant.

  9. Polarized scattering of light for arbitrary magnetic fields with level-crossings from the combination of hyperfine and fine structure splittings

    CERN Document Server

    Sowmya, K; Sampoorna, M; Stenflo, J O

    2015-01-01

    Interference between magnetic substates of the hyperfine structure states belonging to different fine structure states of the same term influences the polarization for some of the diagnostically important lines of the Sun's spectrum, like the sodium and lithium doublets. The polarization signatures of this combined interference contain information on the properties of the solar magnetic fields. Motivated by this, in the present paper, we study the problem of polarized scattering on a two-term atom with hyperfine structure by accounting for the partial redistribution in the photon frequencies arising due to the Doppler motions of the atoms. We consider the scattering atoms to be under the influence of a magnetic field of arbitrary strength and develop a formalism based on the Kramers--Heisenberg approach to calculate the scattering cross section for this process. We explore the rich polarization effects that arise from various level-crossings in the Paschen--Back regime in a single scattering case using the li...

  10. Cavity QED with Multiple Hyperfine Levels

    CERN Document Server

    Birnbaum, K M; Kimble, H J

    2006-01-01

    We calculate the weak-driving transmission of a linearly polarized cavity mode strongly coupled to the D2 transition of a single Cesium atom. Results are relevant to future experiments with microtoroid cavities, where the single-photon Rabi frequency g exceeds the excited-state hyperfine splittings, and photonic bandgap resonators, where g is greater than both the excited- and ground-state splitting.

  11. POLARIZED SCATTERING OF LIGHT FOR ARBITRARY MAGNETIC FIELDS WITH LEVEL-CROSSINGS FROM THE COMBINATION OF HYPERFINE AND FINE STRUCTURE SPLITTINGS

    Energy Technology Data Exchange (ETDEWEB)

    Sowmya, K.; Nagendra, K. N.; Sampoorna, M. [Indian Institute of Astrophysics, Koramangala, Bengaluru (India); Stenflo, J. O., E-mail: ksowmya@iiap.res.in, E-mail: knn@iiap.res.in, E-mail: sampoorna@iiap.res.in, E-mail: stenflo@astro.phys.ethz.ch [Institute of Astronomy, ETH Zurich, CH-8093 Zurich (Switzerland)

    2015-12-01

    Interference between magnetic substates of the hyperfine structure states belonging to different fine structure states of the same term influences the polarization for some of the diagnostically important lines of the Sun's spectrum, like the sodium and lithium doublets. The polarization signatures of this combined interference contain information on the properties of the solar magnetic fields. Motivated by this, in the present paper, we study the problem of polarized scattering on a two-term atom with hyperfine structure by accounting for the partial redistribution in the photon frequencies arising due to the Doppler motions of the atoms. We consider the scattering atoms to be under the influence of a magnetic field of arbitrary strength and develop a formalism based on the Kramers–Heisenberg approach to calculate the scattering cross section for this process. We explore the rich polarization effects that arise from various level-crossings in the Paschen–Back regime in a single scattering case using the lithium atomic system as a concrete example that is relevant to the Sun.

  12. Polarized Scattering of Light for Arbitrary Magnetic Fields with Level-crossings from the Combination of Hyperfine and Fine Structure Splittings

    Science.gov (United States)

    Sowmya, K.; Nagendra, K. N.; Sampoorna, M.; Stenflo, J. O.

    2015-12-01

    Interference between magnetic substates of the hyperfine structure states belonging to different fine structure states of the same term influences the polarization for some of the diagnostically important lines of the Sun's spectrum, like the sodium and lithium doublets. The polarization signatures of this combined interference contain information on the properties of the solar magnetic fields. Motivated by this, in the present paper, we study the problem of polarized scattering on a two-term atom with hyperfine structure by accounting for the partial redistribution in the photon frequencies arising due to the Doppler motions of the atoms. We consider the scattering atoms to be under the influence of a magnetic field of arbitrary strength and develop a formalism based on the Kramers-Heisenberg approach to calculate the scattering cross section for this process. We explore the rich polarization effects that arise from various level-crossings in the Paschen-Back regime in a single scattering case using the lithium atomic system as a concrete example that is relevant to the Sun.

  13. O(alpha(3) lnalpha) corrections to muonium and positronium hyperfine splitting.

    Science.gov (United States)

    Melnikov, K; Yelkhovsky, A

    2001-02-19

    We compute O(alpha(3)lnalpha) relative corrections to the ground-state hyperfine splitting of a QED two-body bound state with different masses of constituents. The general result is then applied to muonium and positronium. In particular, a new value of the muon-to-electron mass ratio is derived from the muonium ground-state hyperfine splitting.

  14. Coulomb Artifacts and Bottomonium Hyperfine Splitting in Lattice NRQCD

    CERN Document Server

    Liu, Tao; Rayyan, Ahmed

    2016-01-01

    We study the role of the lattice artifacts associated with the Coulomb binding effects in the analysis of the heavy quarkonium within lattice NRQCD. We find that a "na\\"ive" perturbative matching generates spurious linear Coulomb artifacts, which result in a large systematic error in the lattice predictions for the heavy quarkonium spectrum. This effect is responsible, in particular, for the discrepancy between the recent determinations of the bottomonium hyperfine splitting in the radiatively improved lattice NRQCD [1, 2]. We show that the correct matching procedure which provides full control over discretization errors is based on the asymptotic expansion of the lattice theory about the continuum limit, which gives $M_{\\Upsilon(1S)}-M_{\\eta_b(1S)}=52.9\\pm 5.5~{\\rm MeV}$ [1].

  15. New Precision Measurement of Hyperfine Splitting of Positronium

    CERN Document Server

    Ishida, A; Asai, S; Kobayashi, T; Saito, H; Yoshida, M; Tanaka, K; Yamamoto, A

    2014-01-01

    The ground state hyperfine splitting of positronium $\\Delta_{\\mathrm{HFS}}$ is sensitive to high order corrections of quantum electrodynamics (QED) in bound state. The theoretical prediction and the averaged experimental value for $\\Delta_{\\mathrm{HFS}}$ has a discrepancy of 15 ppm, which is equivalent to 3.9 standard deviations (s.d.). A new precision measurement which reduces the systematic uncertainty from the positronium thermalization effect was performed, in which the non-thermalization effect was measured to be as large as $10 \\pm 1\\,{\\mathrm{ppm}}$ in a timing window we used. When this effect is taken into account, our new result becomes $\\Delta_{\\mathrm{HFS}} = 203.394\\,1 \\pm 0.001\\,6 ({\\mathrm{stat., 8.0\\,ppm}}) \\pm 0.001\\,1 ({\\mathrm{sys., 5.4\\,ppm}})$\\,GHz, which favors the QED prediction within 1.2 s.d. and disfavors the previous experimental average by 2.7 s.d.

  16. New Precise Measurement of the Hyperfine Splitting of Positronium

    Energy Technology Data Exchange (ETDEWEB)

    Ishida, A., E-mail: ishida@icepp.s.u-tokyo.ac.jp [Department of Physics, Graduate School of Science, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033 (Japan)

    2015-09-15

    Positronium (Ps) is an ideal system for precision test of bound state quantum electrodynamics. The hyperfine splitting (HFS) of the ground state of Ps, which is one of the most precisely tested quantity, has a large discrepancy of 16 ppm (4.5 σ) between previous experiments and theoretical calculation up to O(α{sup 3}lnα{sup −1}) and part of O(α{sup 3}) corrections. A new experiment which reduces possible systematic uncertainties of Ps thermalization effect and nonuniformity of magnetic field was performed. It revealed that the Ps thermalization effect was as large as 10 ± 2 ppm. Treating the thermalization effect correctly, a new result of 203.3942 ± 0.0016(stat., 8.0 ppm) ± 0.0013(sys., 6.4 ppm) GHz was obtained. This result is consistent with theory within 1.1 σ, whereas it disfavors the previous experimental result by 2.6 σ. It shows that the Ps thermalization effect is crucial for precision measurement of HFS. Future prospects for improved precision are briefly discussed.

  17. Towards the measurement of the ground-state hyperfine splitting of antihydrogen

    Energy Technology Data Exchange (ETDEWEB)

    Juhasz, Bertalan, E-mail: bertalan.juhasz@oeaw.ac.at [Austrian Academy of Sciences, Stefan Meyer Institute for Subatomic Physics (Austria)

    2012-12-15

    The ASACUSA collaboration at the Antiproton Decelerator of CERN is planning to measure the ground-state hyperfine splitting of antihydrogen using an atomic beam line, which will consist of a superconducting cusp trap as a source of partially polarized antihydrogen atoms, a radiofrequency spin-flip cavity, a superconducting sextupole magnet as spin analyser, and an antihydrogen detector. This will be a measurement of the antiproton magnetic moment, and also a test of the CPT invariance. Monte Carlo simulations predict that the antihydrogen ground-state hyperfine splitting can be determined with a relative precision of better than {approx} 10{sup - 6}. The first preliminary measurements of the hyperfine transitions will start in 2011.

  18. Torsionally mediated spin-rotation hyperfine splittings at moderate to high J values in methanol

    Science.gov (United States)

    Belov, S. P.; Golubiatnikov, G. Yu.; Lapinov, A. V.; Ilyushin, V. V.; Alekseev, E. A.; Mescheryakov, A. A.; Hougen, J. T.; Xu, Li-Hong

    2016-07-01

    This paper presents an explanation based on torsionally mediated proton-spin-overall-rotation interaction for the observation of doublet hyperfine splittings in some Lamb-dip sub-millimeter-wave transitions between ground-state torsion-rotation states of E symmetry in methanol. These unexpected doublet splittings, some as large as 70 kHz, were observed for rotational quantum numbers in the range of J = 13 to 34, and K = - 2 to +3. Because they increase nearly linearly with J for a given branch, we confined our search for an explanation to hyperfine operators containing one nuclear-spin angular momentum factor I and one overall-rotation angular momentum factor J (i.e., to spin-rotation operators) and ignored both spin-spin and spin-torsion operators, since they contain no rotational angular momentum operator. Furthermore, since traditional spin-rotation operators did not seem capable of explaining the observed splittings, we constructed totally symmetric "torsionally mediated spin-rotation operators" by multiplying the E-species spin-rotation operator by an E-species torsional-coordinate factor of the form e±niα. The resulting operator is capable of connecting the two components of a degenerate torsion-rotation E state. This has the effect of turning the hyperfine splitting pattern upside down for some nuclear-spin states, which leads to bottom-to-top and top-to-bottom hyperfine selection rules for some transitions, and thus to an explanation for the unexpectedly large observed hyperfine splittings. The constructed operator cannot contribute to hyperfine splittings in the A-species manifold because its matrix elements within the set of torsion-rotation A1 and A2 states are all zero. The theory developed here fits the observed large doublet splittings to a root-mean-square residual of less than 1 kHz and predicts unresolvable splittings for a number of transitions in which no doublet splitting was detected.

  19. Transition energy and lifetime for the ground state hyperfine splitting of high Z lithium-like ions

    CERN Document Server

    Shabaev, V M; Tupitsyn, I; Yerokhin, V A; Artemiev, A N; Kühl, T; Tomaselli, M; Zherebtsov, O M

    1998-01-01

    The ground state hyperfine splitting values and the transition probabilities between the hyperfine structure components of high Z lithiumlike ions are calculated in the range Z=49-83. The relativistic, nuclear, QED and interelectronic interaction corrections are taken into account. It is found that the Bohr-Weisskopf effect can be eliminated in a combination of the hyperfine splitting values of the hydrogenlike and lithiumlike ions of an isotope. This gives a good possibility for testing the QED effects in a combination of the strong electric and magnetic fields of the heavy nucleus. Using the experimental result for the 1s hyperfine splitting in ^{209}Bi^{82+}, the 2s hyperfine splitting in ^{209}Bi^{80+} is calculated to be \\Delta E=0.7981(2) eV while the contribution derived from QED constitutes 0.0007(1) eV.

  20. 2S-2P Lamb shift and 2S hyperfine splitting in muonic hydrogen

    CERN Document Server

    Antognini, Aldo; Biraben, François; Indelicato, Paul; Nez, François; Pohl, Randolf

    2012-01-01

    The 7 standard deviations between the proton rms charge radius from muonic hydrogen and the CODATA-10 value from hydrogen spectroscopy and electron-scattering has caused considerable discussions. Here, we review the theory of the 2S-2P Lamb shift and 2S hyperfine splitting in muonic hydrogen combining the published contributions and theoretical approaches. The prediction of these quantities is necessary for the determination of both proton charge and Zemach radii from the two 2S-2P transition frequencies measured in muonic hydrogen.

  1. Thin-film superconducting resonator tunable to the ground-state hyperfine splitting of $^{87}$Rb

    CERN Document Server

    Kim, Z; Hoffman, J E; Grover, J A; Voigt, K D; Cooper, B K; Ballard, C J; Palmer, B S; Hafezi, M; Taylor, J M; Anderson, J R; Dragt, A J; Lobb, C J; Orozco, L A; Rolston, S L; Wellstood, F C

    2011-01-01

    We describe a thin-film superconducting Nb microwave resonator, tunable to within 0.3 ppm of the hyperfine splitting of $^{87}$Rb at $f_{Rb}=6.834683$ GHz. We coarsely tuned the resonator using electron-beam lithography, decreasing the resonance frequency from 6.8637 GHz to 6.8278 GHz. For \\emph{in situ} fine tuning at 15 mK, the resonator inductance was varied using a piezoelectric stage to move a superconducting pin above the resonator. We found a maximum frequency shift of about 8.7 kHz per 60-nm piezoelectric step and a tuning range of 18 MHz.

  2. Hyperfine Splitting in True Muonium to $\\mathcal{O}(m_\\mu\\alpha^6)$: Two Photon Annihilation Contribution from Other Flavors

    CERN Document Server

    Ji, Yao

    2016-01-01

    The two-photon-annihilation contribution to the true muonium hyperfine splitting arising from $e$ and $\\tau$ loops is obtained analytically at order $m_\\mu\\alpha^6$. The contribution to the hyperfine splitting is $-2.031092873 m_\\mu\\alpha^6/n^3\\pi^2=-793.926988/n^3$ MHz. The contribution to the triplet true muonium decay rate has also been obtained and was found to be $9.825708266 m_\\mu\\alpha^6/n^3\\pi^2=3840.737698/n^3$ MHz. Additional results have been computed for other purely leptonic bound states.

  3. Vacuum polarization and quadrupole corrections to the hyperfine splitting of P-states in muonic deuterium

    CERN Document Server

    Martynenko, A P

    2016-01-01

    On the basis of quasipotential approach in quantum electrodynamics we calculate vacuum polarization and quadrupole corrections in first and second orders of perturbation theory in hyperfine structure of P-states in muonic deuterium. All corrections are presented in integral form and evaluated analytically and numerically. The obtained results can be used for the improvement of the transition frequencies between levels 2P and 2S.

  4. Quantum Chemical Calculations of Torsionally Mediated Hyperfine Splittings in States of E Symmetry of Acetaldehyde (CH_{3}CHO)

    Science.gov (United States)

    Xu, Li-Hong; Reid, Elias M.; Guislain, Bradley; Hougen, Jon T.; Alekseev, E. A.; Krapivin, Igor

    2017-06-01

    Hyperfine splittings in methanol have been revisited in three recent publications. (i) Coudert et al. [JCP 143 (2015) 044304] published an analysis of splittings observed in the low-J range. They calculated 32 spin-rotation, 32 spin-spin, and 16 spin-torsion hyperfine constants using the ACES2 package. Three of these constants were adjusted to fit hyperfine patterns for 12 transitions. (ii) Three present authors and collaborators [JCP 145 (2016) 024307] analyzed medium to high-J experimental Lamb-dip measurements in methanol and presented a theoretical spin-rotation explanation that was based on torsionally mediated spin-rotation hyperfine operators. These contain, in addition to the usual nuclear spin and overall rotational operators, factors in the torsional angle α of the form {e^{plusmn;{inα}}}. Such operators have non-zero matrix elements between the two components of a torsion-rotation ^{tr}E state, but have zero matrix elements within a ^{tr}A state. More than 55 hyperfine splittings were successfully fitted using three parameters and the fitted values agree well with ab initio values obtained in (i). (iii) Lankhaar et al. [JCP 145 (2016) 244301] published a reanalysis of the data set from (i), using CFOUR recalculated hyperfine constants based on their rederivation of the relevant expressions. They explain why their choice of fixed and floated parameters leads to numerical values for all parameters that seem to be more physical than those in (i). The results in (ii) raise the question of whether large torsionally-mediated spin-rotation splittings will occur in other methyl-rotor-containing molecules. This abstract presents ab initio calculations of torsionally mediated hyperfine splittings in the E states of acetaldehyde using the same three operators as in (ii) and spin-rotation constants computed by Gaussian09. We explored the first 13 K states for J from 10 to 40 and ν_{t} = 0, 1, and 2. Our calculations indicate that hyperfine splittings in CH_{3}CHO

  5. Laser spectroscopy of the ground state hyperfine splittings of $^{209}$Bi$^{82+}$ and $^{209}$Bi$^{80+}$

    CERN Document Server

    Lochmann, Matthias; Geppert, Christopher; Andelkovic, Zoran; Anielski, Denis; Botermann, Benjamin; Bussmann, Michael; Dax, Andreas; Frömmgen, Nadja; Hammen, Michael; Hannen, Volker; Kühl, Thomas; Litvinov, Yuri A; López-Coto, Rubén; Stöhlker, Thomas; Thompson, Richard C; Vollbrecht, Jonas; Volotka, Andrey; Weinheimer, Christian; Wen, Weiqiang; Will, Elisa; Winters, Danyal; Sánchez, Rodolfo; Nörtershäuser, Wilfried

    2014-01-01

    We performed a laser spectroscopic determination of the $2s$ hyperfine structure (HFS) splitting of lithiumlike $^{209}\\text{Bi}^{80+}$ for the first time and repeated the measurement of the $1s$ HFS splitting of hydrogenlike $^{209}\\text{Bi}^{82+}$. Both ion species were subsequently stored in the Experimental Storage Ring at GSI and cooled with an electron cooler at a velocity of $\\approx 0.71\\,c$. Pulsed laser excitation of the M1 HFS-transition was performed in anticollinear and collinear geometry for $^{209}\\text{Bi}^{82+}$ and $^{209}\\text{Bi}^{80+}$, respectively, and observed by fluorescence detection. We obtain $\\Delta E^{(1s)}= 5086.3(11)\\,\\textrm{meV}$ for $^{209}\\text{Bi}^{82+}$ and $\\Delta E^{(2s)}= 797.50(18)\\,\\textrm{meV}$ for $^{209}\\text{Bi}^{80+}$. A specific difference between the two splitting energies can be used to test QED calculations in the strongest static magnetic fields available in the laboratory independent of nuclear structure effects. Our results confirm the large relativistic ...

  6. Measurement of the hyperfine splitting of {sup 133}Cs atoms in superfluid helium

    Energy Technology Data Exchange (ETDEWEB)

    Imamura, K., E-mail: kimamura@riken.jp [RIKEN Nishina Center (Japan); Furukawa, T. [Tokyo Metropolitan University, Department of Physics (Japan); Yang, X. F. [Peking University, School of Physics (China); Mitsuya, Y. [Meiji University, Department of Physics (Japan); Fujita, T. [Osaka University, Department of Physics (Japan); Hayasaka, M. [Tokyo Gakugei University, Department of Physics (Japan); Kobayashi, T. [RIKEN Center for Advanced Photonics (Japan); Hatakeyama, A. [Tokyo University of Agriculture and Technology, Department of Applied Physics (Japan); Ueno, H. [RIKEN Nishina Center (Japan); Odashima, H. [Meiji University, Department of Physics (Japan); Matsuo, Y. [Hosei University, Department of Advanced Sciences (Japan)

    2015-04-15

    We have been developing a new nuclear laser spectroscopy method named “OROCHI” (Optical RI-atom Observation in Condensed Helium as Ion-catcher). OROCHI utilizes superfluid helium (He II) not only as an efficient stopping medium of highly energetic ions but also as a host matrix of in-situ atomic laser spectroscopy. Using these characteristic of He II, we produce atomic spin polarization and measure Zeeman and hyperfine structure (HFS) splitting using laser-RF (radio frequency) / MW (microwave) double resonance method. From the measured energy splittings, we can deduce nuclear spins and moments. So far, we have conducted a series of experiments using both stable ({sup 85,87}Rb, {sup 133}Cs, {sup 197}Au, {sup 107,109}Ag) and unstable isotopes ({sup 84,86}Rb) to confirm the feasibility of OROCHI method, especially observing Zeeman resonance and determining nuclear spins. The measurement of HFS splitting of atoms introduced into He II is indispensable to clarify the nuclear properties by deducing nuclear moments as well as the study of nuclear spins. For this purpose, we perform a precision measurement of HFS of {sup 133}Cs atoms immersed in He II using laser ablation technique. In this paper, we describe the result of the experiment.

  7. Hadronic contributions to the anomalous magnetic moment of the electron and the hyperfine splitting of muonium

    Energy Technology Data Exchange (ETDEWEB)

    Nomura, Daisuke, E-mail: dnomura@tuhep.phys.tohoku.ac.jp [Department of Physics, Tohoku University, Sendai 980-8578 (Japan); Teubner, Thomas [Department of Mathematical Sciences, University of Liverpool, Liverpool L69 3BX (United Kingdom)

    2013-02-11

    Motivated by recent progress of theory and experiment on the anomalous magnetic moment of the electron, a{sub e}, we update the hadronic contributions to a{sub e}. Using our up-to-date compilation of e{sup +}e{sup -}{yields}hadrons data, we find the leading order hadronic contribution a{sub e}{sup had,LO,VP}=(1.866{+-}0.010{sub exp}{+-}0.005{sub rad}) Dot-Operator 10{sup -12} and the next-to-leading order hadronic contribution a{sub e}{sup had,NLO,VP}=(-0.2234{+-}0.0012{sub exp}{+-}0.0007{sub rad}) Dot-Operator 10{sup -12}, where the first and second errors are from the error of the experimental data and the uncertainty in the treatment of radiative corrections, respectively. These values are compatible with earlier evaluations by other groups, but have significantly improved uncertainties due to the more precise input data used. We also update the leading order hadronic contribution to the ground state hyperfine splitting of muonium, obtaining {Delta}{nu}{sub Mu}{sup had,VP}=(232.68{+-}1.25{sub exp}{+-}0.72{sub rad}) Hz. This value is consistent with the most precise evaluation in the literature and reduces its error by a factor of two.

  8. Hyperfine splitting of B mesons and B sub s production at the. Upsilon. (5 S )

    Energy Technology Data Exchange (ETDEWEB)

    Lee-Franzini, J.; Heintz, U.; Lovelock, D.M.J.; Narain, M.; Schamberger, R.D.; Willins, J.; Yanagisawa, C. (The State University of New York at Stony Brook, Stony Brook, NY (USA)); Franzini, P.; Tuts, P.M. (Columbia University, New York, NY (USA))

    1990-12-10

    Using the Columbia University--Stony Brook (CUSB-II) detector we have studied the inclusive photon spectrum from 2.9{times}10{sup 4} {Upsilon}(5{ital S}) decays. We observe a strong signal due to {ital B}{sup *}{r arrow}{ital B}{gamma} decays. From this we obtain (i) the average {ital B}{sup *}-{ital B} mass difference, 46.7{plus minus}0.4 MeV, (ii) the photon yield per {Upsilon}(5{ital S}) decay, {l angle}{gamma}/{Upsilon}(5{ital S}){r angle}=1.09{plus minus}0.06, and (iii) the average velocity of the {ital B}{sup *}'s, {l angle}{beta}{r angle}=0.156{plus minus}0.010, for a mix of nonstrange ({ital B}) and strange ({ital B}{sub {ital s}}) {ital B}{sup *} mesons from {Upsilon}(5{ital S}) decays. From the shape of the photon line, we find that both {ital B} and {ital B}{sub {ital s}} mesons are produced with nearly equal values for the hyperfine splitting of the {ital B} and {ital B}{sub {ital s}} meson systems.

  9. High-accuracy measurement of the {sup 87}Rb ground-state hyperfine splitting in an atomic fountain

    Energy Technology Data Exchange (ETDEWEB)

    Bize, S.; Sortais, Y.; Clairon, A. [Observatoire de Paris (France). BNM-LPTF; Santos, M.S. [Inst. de Fisica de Sao Carlos-USP, Dept. de Fisica e Ciencia dos Materiais, Sao Carlos (Brazil); Mandache, C. [Inst. National de Fizica Laserilor, Plasmei si Radiatiei, Bucuresti, Magurele (Romania); Salomon, C. [Lab. Kastler Brossel, Ecole Normale Superieure, Paris (France)

    1999-03-01

    We describe the operation of a laser-cooled rubidium {sup 87}Rb frequency standard. We present a new measurement of the {sup 87}Rb hyperfine frequency with a 1.3 x 10{sup -14} relative accuracy, by comparison with a Cs fountain primary standard. The measured {sup 87}Rb ground-state hyperfine splitting is {nu}{sup {sub 87}}{sub Rb} = 6 834 682 610.90429(9) Hz. This value differs from previously published values (see Essen L., Hope E. G. and Sutcliffe D. (1961); Penselin S., Moran T., Cohen W. and Winkler G. (1962); Arditi M. and Cerez P. (1972)) by about 2-3 Hz and is 10{sup 4} times more accurate. Because of the low collisional shift in {sup 87}Rb, future improvements may lead to a stability of 1 x 10{sup -14}{tau}{sup -1/2} and a relative accuracy in the 10{sup -17} range. (orig.) 23 refs.

  10. Towards measuring the ground state hyperfine splitting of antihydrogen – a progress report

    Energy Technology Data Exchange (ETDEWEB)

    Sauerzopf, C., E-mail: clemens.sauerzopf@oeaw.ac.at; Capon, A. A.; Diermaier, M. [Stefan Meyer Institute for subatomic physics, Austrian Academy of Sciences (Austria); Dupré, P. [Atomic Physics Laboratory, RIKEN (Japan); Higashi, Y. [University of Tokyo, Institute of Physics, Graduate School of Arts and Sciences (Japan); Kaga, C. [Hiroshima University, Graduate School of Advanced Sciences of Matter (Japan); Kolbinger, B. [Stefan Meyer Institute for subatomic physics, Austrian Academy of Sciences (Austria); Leali, M. [Università di Brescia, Dipartimento di Ingegneria dell’ Informazione (Italy); Lehner, S. [Stefan Meyer Institute for subatomic physics, Austrian Academy of Sciences (Austria); Rizzini, E. Lodi [Università di Brescia, Dipartimento di Ingegneria dell’ Informazione (Italy); Malbrunot, C. [Stefan Meyer Institute for subatomic physics, Austrian Academy of Sciences (Austria); Mascagna, V. [Università di Brescia, Dipartimento di Ingegneria dell’ Informazione (Italy); Massiczek, O. [Stefan Meyer Institute for subatomic physics, Austrian Academy of Sciences (Austria); Murtagh, D. J.; Nagata, Y.; Radics, B. [Atomic Physics Laboratory, RIKEN (Japan); Simon, M. C.; Suzuki, K. [Stefan Meyer Institute for subatomic physics, Austrian Academy of Sciences (Austria); Tajima, M. [University of Tokyo, Institute of Physics, Graduate School of Arts and Sciences (Japan); Ulmer, S. [Ulmer Initiative Research Unit, RIKEN (Japan); and others

    2016-12-15

    We report the successful commissioning and testing of a dedicated field-ioniser chamber for measuring principal quantum number distributions in antihydrogen as part of the ASACUSA hyperfine spectroscopy apparatus. The new chamber is combined with a beam normalisation detector that consists of plastic scintillators and a retractable passivated implanted planar silicon (PIPS) detector.

  11. Towards Measuring the Ground State Hyperfine Splitting of Antihydrogen -- A Progress Report

    CERN Document Server

    Sauerzopf, C.

    2016-06-20

    We report the successful commissioning and testing of a dedicated field-ioniser chamber for measuring principal quantum number distributions in antihydrogen as part of the ASACUSA hyperfine spectroscopy apparatus. The new chamber is combined with a beam normalisation detector that consists of plastic scintillators and a retractable passivated implanted planar silicon (PIPS) detector.

  12. Radiative Transfer of HCN: Interpreting observations of hyperfine anomalies

    CERN Document Server

    Mullins, A M; Redman, M P; Wiles, B; Guegan, N; Barrett, J; Keto, E R

    2016-01-01

    Molecules with hyperfine splitting of their rotational line spectra are useful probes of optical depth, via the relative line strengths of their hyperfine components.The hyperfine splitting is particularly advantageous in interpreting the physical conditions of the emitting gas because with a second rotational transition, both gas density and temperature can be derived. For HCN however, the relative strengths of the hyperfine lines are anomalous. They appear in ratios which can vary significantly from source to source, and are inconsistent with local thermodynamic equilibrium. This is the HCN hyperfine anomaly, and it prevents the use of simple LTE models of HCN emission to derive reliable optical depths. In this paper we demonstrate how to model HCN hyperfine line emission, and derive accurate line ratios, spectral line shapes and optical depths. We show that by carrying out radiative transfer calculations over each hyperfine level individually, as opposed to summing them over each rotational level, the anom...

  13. Hyperfine splitting in non-relativistic QED: uniqueness of the dressed hydrogen atom ground state

    CERN Document Server

    Amour, Laurent

    2011-01-01

    We consider a free hydrogen atom composed of a spin-1/2 nucleus and a spin-1/2 electron in the standard model of non-relativistic QED. We study the Pauli-Fierz Hamiltonian associated with this system at a fixed total momentum. For small enough values of the fine-structure constant, we prove that the ground state is unique. This result reflects the hyperfine structure of the hydrogen atom ground state.

  14. Status Report: A Detector for Measuring the Ground State Hyperfine Splitting of Antihydrogen

    CERN Document Server

    Kolbinger, Bernadette

    2016-01-01

    The ASACUSA (Atomic Spectroscopy And Collisions Using Slow Antiprotons) collaboration at the Antiproton Decelerator at CERN aims to measure the ground state hyperfine structure of antihydrogen. A Rabi-like spectrometer line has been built for this purpose. A detector for counting antihydrogen is located at the end of the beam line. This contribution will focus on the tracking detector, whose challenging task it is to discriminate between background events and antiproton annihilations originating from antihydrogen atoms which are produced only in small amounts.

  15. Steps towards the hyperfine splitting measurement of the muonic hydrogen ground state: pulsed muon beam and detection system characterization

    CERN Document Server

    Adamczak, A; Bakalov, D; Baldazzi, G; Bertoni, R; Bonesini, M; Bonvicini, V; Campana, G; Carbone, R; Cervi, T; Chignoli, F; Clemenza, M; Colace, L; Curioni, A; Danailov, M; Danev, P; D'Antone, I; De, A; De, C; De, M; Furini, M; Fuschino, F; Gadejisso-Tossou, K; Guffanti, D; Iaciofano, A; Ishida, K; Iugovaz, D; Labanti, C; Maggi, V; Margotti, A; Marisaldi, M; Mazza, R; Meneghini, S; Menegolli, A; Mocchiutti, E; Moretti, M; Morgante, G; Nardò, R; Nastasi, M; Niemela, J; Previtali, E; Ramponi, R; Rachevski, A; P., L; Rossella, M; Rossi, P L; Somma, F; Stoilov, M; Stoychev, L; Tomaselli, A; Tortora, L; Vacchi, A; Vallazza, E; Zampa, G; Zuffa, M

    2016-01-01

    The high precision measurement of the hyperfine splitting of the muonic-hydrogen atom ground state with pulsed and intense muon beam requires careful technological choices both in the construction of a gas target and of the detectors. In June 2014, the pressurized gas target of the FAMU experiment was exposed to the low energy pulsed muon beam at the RIKEN RAL muon facility. The objectives of the test were the characterization of the target, the hodoscope and the X-ray detectors. The apparatus consisted of a beam hodoscope and X-rays detectors made with high purity Germanium and Lanthanum Bromide crystals. In this paper the experimental setup is described and the results of the detector characterization are presented.

  16. Quarkonium fine-hyperfine splittings and the Lorentz structure of the confining potential with vacuum-polarization corrections

    Energy Technology Data Exchange (ETDEWEB)

    Barik, N.; Jena, S.N.

    1980-06-01

    Within the framework of the Poggio-Schnitzer flavor-independent static-potential model with long-distance vacuum-polarization correction, we analyze the Lorentz-Dirac structure of the confinement potential with reference to the charmonium hyperfine splittings. In view of the questionable existence and/or doubtful identity of the X(2830) and chi(3455) states, we give preference to the Lorentz-Dirac character of the confinement potential in the form of an approximately equal admixture of scalar and vector components with no anomalous moment. This in turn predicts the /sup 1/S/sub 0/ partners of psi and psi' to be near the 3.0- and 3.6-GeV mass regions, respectively. This also suggests the /sup 1/P/sub 1/ state of charmonium is to be found above the /sup 3/P/sub 0/ state near the mass region of 3.48 GeV.

  17. Radiative transfer of HCN: interpreting observations of hyperfine anomalies

    Science.gov (United States)

    Mullins, A. M.; Loughnane, R. M.; Redman, M. P.; Wiles, B.; Guegan, N.; Barrett, J.; Keto, E. R.

    2016-07-01

    Molecules with hyperfine splitting of their rotational line spectra are useful probes of optical depth, via the relative line strengths of their hyperfine components. The hyperfine splitting is particularly advantageous in interpreting the physical conditions of the emitting gas because with a second rotational transition, both gas density and temperature can be derived. For HCN however, the relative strengths of the hyperfine lines are anomalous. They appear in ratios which can vary significantly from source to source, and are inconsistent with local thermodynamic equilibrium (LTE). This is the HCN hyperfine anomaly, and it prevents the use of simple LTE models of HCN emission to derive reliable optical depths. In this paper, we demonstrate how to model HCN hyperfine line emission, and derive accurate line ratios, spectral line shapes and optical depths. We show that by carrying out radiative transfer calculations over each hyperfine level individually, as opposed to summing them over each rotational level, the anomalous hyperfine emission emerges naturally. To do this requires not only accurate radiative rates between hyperfine states, but also accurate collisional rates. We investigate the effects of different sets of hyperfine collisional rates, derived via the proportional method and through direct recoupling calculations. Through an extensive parameter sweep over typical low-mass star-forming conditions, we show the HCN line ratios to be highly variable to optical depth. We also reproduce an observed effect whereby the red-blue asymmetry of the hyperfine lines (an infall signature) switches sense within a single rotational transition.

  18. Hyperfine splitting of the dressed hydrogen atom ground state in non-relativistic QED

    CERN Document Server

    Amour, L

    2010-01-01

    We consider a spin-1/2 electron and a spin-1/2 nucleus interacting with the quantized electromagnetic field in the standard model of non-relativistic QED. For a fixed total momentum sufficiently small, we study the multiplicity of the ground state of the reduced Hamiltonian. We prove that the coupling between the spins of the charged particles and the electromagnetic field splits the degeneracy of the ground state.

  19. Test of the theoretical hyperfine structure of the molecular hydrogen ion at the 1-ppm level

    CERN Document Server

    Korobov, Vladimir I; Hilico, Laurent; Karr, Jean-Philippe

    2015-01-01

    We revisit the $m \\alpha^6 (m/M)$ order corrections to the hyperfine splitting in the H$_2^+$ ion, and find a hitherto unrecognized second-order relativistic contribution associated with the vibrational motion of the nuclei. Inclusion of this correction term produces theoretical predictions which are in excellent agreement with experimental data [K. B. Jefferts, Phys.\\ Rev.\\ Lett.\\ \\textbf{23}, 1476 (1969)], thereby concluding a nearly fifty years long theoretical quest to explain the experimental results within their 1-ppm error. The agreement between theory and experiment corroborates the proton structural properties as derived from the hyperfine structure of atomic hydrogen. Our work furthermore indicates that for future improvements, a full three-body evaluation of the $m \\alpha^6 (m/M)$ correction term will be mandatory.

  20. Calculation of hyperfine interaction in spherical quantum dot

    Science.gov (United States)

    Yakar, Yusuf; Çakır, Bekir; Özmen, Ayhan

    2015-10-01

    In this study, we have calculated the unperturbed wavefunctions and energy eigenvalues of the ground and excited states of a spherical quantum dot, GaAs/AlxGa1-xAs, by using quantum genetic algorithm and Hartree-Fock Roothaan method. Hyperfine coupling constant and hyperfine energy of 1s, 2p, 3d and 4f levels are carried out as a function of dot radius. The results show that the hyperfine constant and hyperfine energy varies rapidly in the strong and medium confining regions as dot radius decreases. It is worth pointing out that dot radius, impurity charge and angular momentum have a strong influence on the hyperfine energy. It is also found that hyperfine energy and hyperfine splitting vary with aluminium concentration ratio x.

  1. Electron paramagnetic resonance spectroscopy of lactoperoxidase complexes: clarification of hyperfine splitting for the NO adduct of lactoperoxidase

    Energy Technology Data Exchange (ETDEWEB)

    Lukat, G.S.; Rodgers, K.R.; Goff, H.M.

    1987-11-03

    Electron paramagnetic resonance (EPR) studies of the nitrosyl adduct of ferrous lactoperoxidase (LPO) confirm that the fifth axial ligand in LPO is bound to the iron via a nitrogen atom. Complete reduction of the ferric LPO sample is required in order to observe the nine-line hyperfine splitting in the ferrous LPO/NO EPR spectrum. The ferrous LPO/NO complex does not exhibit a pH or buffer system dependence when examined by EPR. Interconversion of the ferrous LPO/NO complex and the ferric LPO/NO/sub 2//sup -/ complex is achieved by addition of the appropriate oxidizing or reducing agent. Characterization of the low-spin LPO/NO/sub 2//sup -/ complex by EPR and visible spectroscopy is reported. The pH dependence of the EPR spectra of ferric LPO and ferric LPO/CN/sup -/ suggests that a high-spin anisotrophic LPO complex is formed at high pH and an acid-alkaline transition of the protein conformation near the heme site does occur in LPO/CN/sup -/. The effect of tris(hydroxymethyl)aminomethane buffer on the LPO EPR spectrum is also examined.

  2. State selection of 2/sup 2/Ssub(1/2) hyperfine levels of hydrogen in zero magnetic field

    Energy Technology Data Exchange (ETDEWEB)

    Edwards, J.W.; Greene, G.L.; Hinds, E.A. (Yale Univ., New Haven, CT (USA). Gibbs Lab.)

    1982-06-15

    We describe a methd of hyperfine level selection using rf quenching of a metastable (2S) hydrogen beam in zero magnetic field. The method provides excellent suppression of unwanted states with acceptable transmission of desired states. The technique has been used to study a very weakly induced hyperfine transition.

  3. Level of copper in human split ejaculate.

    Science.gov (United States)

    Skandhan, Kalanghot; Valsa, James; Sumangala, Balakrishnan; Jaya, Vasudevan

    2017-02-03

    The purpose of this study was to understand the details of splits of an ejaculate and to locate the origin of release of copper into semen. Laboratory methods routinely followed for semen analysis were carried out. Copper was estimated by employing atomic absorption spectrophotometry. First split of ejaculate showed the highest number of motile sperm, the quality of which decreased from first to third. Copper level in splits 1, 2 and 3 was 29, 23 and 22 µg%, respectively. This study concluded that copper was released from throughout the genital tract.

  4. Spectrum, radial wave functions, and hyperfine splittings of the Rydberg states in heavy alkali-metal atoms

    Science.gov (United States)

    Sanayei, Ali; Schopohl, Nils

    2016-07-01

    We present numerically accurate calculations of the bound-state spectrum of the highly excited valence electron in the heavy alkali-metal atoms solving the radial Schrödinger eigenvalue problem with a modern spectral collocation method that applies also for a large principal quantum number n ≫1 . As an effective single-particle potential we favor the reputable potential of Marinescu et al. [Phys. Rev. A 49, 982 (1994)], 10.1103/PhysRevA.49.982. Recent quasiclassical calculations of the quantum defect of the valence electron agree for orbital angular momentum l =0 ,1 ,2 ,... overall remarkably well with the results of the numerical calculations, but for the Rydberg states of rubidium and also cesium with l =3 this agreement is less fair. The reason for this anomaly is that in rubidium and cesium the potential acquires for l =3 deep inside the ionic core a second classical region, thus invalidating a standard Wentzel-Kramers-Brillouin (WKB) calculation with two widely spaced turning points. Comparing then our numerical solutions of the radial Schrödinger eigenvalue problem with the uniform analytic WKB approximation of Langer constructed around the remote turning point rn,j ,l (" close=")n -δ0)">+ we observe everywhere a remarkable agreement, apart from a tiny region around the inner turning point rn,j ,l (-). For s states the centrifugal barrier is absent and no inner turning point exists: rn,j ,0 (-)=0 . With the help of an ansatz proposed by Fock we obtain for the s states a second uniform analytic approximation to the radial wave function complementary to the WKB approximation of Langer, which is exact for r →0+ . From the patching condition, that is, for l =0 the Langer and Fock solutions should agree in the intermediate region 0 application we consider recent spectroscopic data for the hyperfine splittings of the isotopes 85Rb and 87Rb and find a remarkable agreement with the predicted scaling relation An,j ,0 (HFS )=const .

  5. Improved measurement of the hyperfine structure of the laser cooling level $4f^{12}(^3 H_6)5d_{5/2}6s^2$ $(J=9/2)$ in $^{169}$Tm

    CERN Document Server

    Fedorov, S A; Kalganova, E S; Sukachev, D D; Golovizin, A A; Tregubov, D O; Khabarova, K Yu; Akimov, A V; Kolachevsky, N N; Sorokin, V N

    2016-01-01

    We report on the improved measurement of the hyperfine structure of $4f^{12}(^3 H_6)5d_{5/2}6s^2$ $(J=9/2)$ excited state in Tm-169 which is involved in the second-stage laser cooling of Tm. To measure the absolute value of the hyperfine splitting interval we used Doppler-free frequency modulation saturated absorption spectroscopy of Tm atoms in a vapor cell. The sign of the hyperfine constant was determined independently by spectroscopy of laser cooled Tm atoms. The hyperfine constant of the level equals $A_J=-422.112(32)$ MHz that corresponds to the energy difference between two hyperfine sublevels of $-2110.56(16)$~MHz. In relation to the saturated absorption measurement we quantitatively treat contributions of various mechanisms into the line broadening and shift. We consider power broadening in the case when Zeeman sublevels of atomic levels are taken into account. We also discuss the line broadening due to frequency modulation and relative intensities of transitions in saturated-absorption experiments.

  6. Radiative nonrecoil nuclear finite size corrections of order α(Zα)5 to the hyperfine splitting of S-states in muonic hydrogen

    Science.gov (United States)

    Faustov, R. N.; Martynenko, A. P.; Martynenko, G. A.; Sorokin, V. V.

    2014-06-01

    On the basis of quasipotential method in quantum electrodynamics we calculate nuclear finite size radiative corrections of order α(Zα)5 to the hyperfine structure of S-wave energy levels in muonic hydrogen and muonic deuterium. For the construction of the particle interaction operator we employ the projection operators on the particle bound states with definite spins. The calculation is performed in the infrared safe Fried-Yennie gauge. Modern experimental data on the electromagnetic form factors of the proton and deuteron are used.

  7. Radiative nonrecoil nuclear finite size corrections of order $\\alpha(Z\\alpha)^5$ to the hyperfine splitting of S-states in muonic hydrogen

    CERN Document Server

    Faustov, R N; Martynenko, G A; Sorokin, V V

    2014-01-01

    On the basis of quasipotential method in quantum electrodynamics we calculate nuclear finite size radiative corrections of order $\\alpha(Z\\alpha)^5$ to the hyperfine structure of S-wave energy levels in muonic hydrogen and muonic deuterium. For the construction of the particle interaction operator we employ the projection operators on the particle bound states with definite spins. The calculation is performed in the infrared safe Fried-Yennie gauge. Modern experimental data on the electromagnetic form factors of the proton and deuteron are used.

  8. Annihilation detector for an in-beam spectroscopy apparatus to measure the ground state hyperfine splitting of antihydrogen

    Science.gov (United States)

    Sauerzopf, Clemens; Capon, Aaron A.; Diermaier, Martin; Fleck, Markus; Kolbinger, Bernadette; Malbrunot, Chloé; Massiczek, Oswald; Simon, Martin C.; Vamosi, Stefan; Zmeskal, Johann; Widmann, Eberhard

    2017-02-01

    The matter-antimatter asymmetry observed in the universe today still lacks a quantitative explanation. One possible mechanism that could contribute to the observed imbalance is a violation of the combined Charge-, Parity- and Time symmetries (CPT). A test of CPT symmetry using anti-atoms is being carried out by the ASACUSA-CUSP collaboration at the CERN Antiproton Decelerator using a low temperature beam of antihydrogen-the most simple atomic system built only of antiparticles. While hydrogen is the most abundant element in the universe, antihydrogen is produced in very small quantities in a laboratory framework. A detector for in-beam measurements of the ground state hyperfine structure of antihydrogen has to be able to detect very low signal rates within high background. To fulfil this challenging task, a two layer barrel hodoscope detector was developed. It is built of plastic scintillators with double sided readout via Silicon Photomultipliers (SiPMs). The SiPM readout is done using novel, compact and cost efficient electronics that incorporate power supply, amplifier and discriminator on a single board. This contribution will evaluate the performance of the new hodoscope detector.

  9. Wavelengths, energy levels and hyperfine structure of Mn II and Sc II.

    Science.gov (United States)

    Nave, Gillian; Pickering, Juliet C.; Townley-Smith, Keeley I. M.; Hala, .

    2015-08-01

    For many decades, the Atomic Spectroscopy Groups at the National Institute of Standards and Technology (NIST) and Imperial College London (ICL) have measured atomic data of astronomical interest. Our spectrometers include Fourier transform (FT) spectrometers at NIST and ICL covering the region 1350 Å to 5.5 μm and a 10.7-m grating spectrometer at NIST covering wavelengths from 300 - 5000 Å. Sources for these spectra include high-current continuous and pulsed hollow cathode (HCL) lamps, Penning discharges, and sliding spark discharges. Recent work has focused on the measurement and analysis of wavelengths, energy levels, and hyperfine structure (HFS) constants for iron-group elements. The analysis of FT spectra of Cr I, Mn I, and Mn II is being led by ICL and is described in a companion poster [1]. Current work being led by NIST includes the analysis of HFS in Mn II, analysis of Mn II in the vacuum ultraviolet, and a comprehensive analysis of Sc II.Comprehensive HFS constants for Mn II are needed for the interpretation of stellar spectra and incorrect abundances may be obtained when HFS is omitted. Holt et al. [2] have measured HFS constants for 59 levels of Mn II using laser spectroscopy. We used FT spectra of Mn/Ni and Mn/Cu HCLs covering wavelength ranges from 1350 Å to 5.4 μm to confirm 26 of the A constants of Holt et al. and obtain values for roughly 40 additional levels. We aim to obtain HFS constants for the majority of lines showing significant HFS that are observed in chemically-peculiar stars.Spectra of Sc HCLs have been recorded from 1800 - 6700 Å using a vacuum ultraviolet FT spectrometer at NIST. Additional measurements to cover wavelengths above 6700 Å and below 1800 Å are in progress. The spectra are being analyzed by NIST and Alighar Muslim University, India in order to derive improved wavelengths, energy levels, and hyperfine structure parameters.This work was partially supported by NASA, the STFC and PPARC (UK), the Royal Society of the UK

  10. Single chirped pulse control of hyperfine states population in Rb atom in the framework of the four-level system

    Science.gov (United States)

    Zakharov, Vladislav; Malinovskaya, Svetlana

    2012-06-01

    Electron population dynamics within the hyperfine structure in the Rb atom induced by a single ns pulse is theoretically investigated. The aim is to develop a methodology of the implementation of linearly chirped laser pulses for the desired excitations in the Rb atoms resulting in the creation of predetermined non-equilibrium states. A semi-classical model of laser pulse interaction with a four-level system representing the hyperfine energy levels of the Rb atom involved into dynamics has been developed. The equations for the probability amplitudes were obtained from the Schrodinger equation with the Hamiltonian that described the time evolution of the population of the four states in the field interaction representation. A code was written in Fortran for a numerical analysis of the time evolution of probability amplitudes as a function of the field parameters. The dependence of the quantum yield on the pulse duration, the linear chirp parameter and the Rabi frequency was studied to reveal the conditions for the entire population transfer to the upper hyperfine state of the 5S1/2 electronic level. The results may provide a robust tool for quantum operations in the alkali atoms.

  11. Hyperfine anomaly in the f{sup 3}ds{sup 2} {sup 5}L{sub 6}{sup 0}, f{sup 3}dsp{sup 7}M{sub 7} and f{sup 3}dsp{sup 7}L{sub 6} levels in U I

    Energy Technology Data Exchange (ETDEWEB)

    Gangrsky, Yu.P.; Markov, B.N.; Zemlyanoi, S.G. [JINR, Dubna (Russian Federation). Lab. of Nucl. Reactions; Kul`djanov, B.K. [AN Uzbekskoj SSR, Tashkent (Uzbekistan). Inst. Yadernoj Fiziki; Marinova, K.P. [Sofia Univ. (Bulgaria). Fizicheski Fakultet

    1997-10-01

    The hyperfine structures of two optical lines in U I were investigated using high resolution laser spectroscopy of a well-collimated atomic beam. The hyperfine splitting constants A and B for the ground {sup 5}L{sub 6}{sup 0} level of {sup 233}U and for the {sup 7}M{sub 7} (16900 cm{sup -1}) and {sup 7}L{sub 6} (17362 cm{sup -1}) excited levels for both long-lived uranium isotopes, {sup 233}U and {sup 235}U, were obtained. Using the ratio of the gyromagnetic factors g{sub 1}({sup 235}U)/g{sub 1}({sup 233}U) = 0.4650(14), directly measured by a paramagnetic resonance absorption experiment, a tendency for existence of a nonvanishing experimental hyperfine anomaly of the order of 1% in the investigated U I levels was shown. (orig.) 17 refs.

  12. Hyperfine Magnetic Anomaly in the Atomic Spectra of the Rare-Earth Elements

    CERN Document Server

    Gangrsky, Yu P; Karaivanov, D V; Kolesnikov, N N; Marinova, K P; Markov, B N; Rostovsky, V S

    2001-01-01

    The constants of the hyperfine splitting in the atomic optical spectra of the rare-earth elements - Nd, Eu, Gd and Lu - were measured. The method of laser resonance fluorescence in the parallel atomic beam was used. The values of the hyperfine magnetic anomaly were determined from the comparison of magnetic dipole constant ratios of the neighbouring odd Z or N isotopes for the different atomic levels. The connection of these values and the parameters of atomic and nuclear structure is discussed.

  13. Theory of the hyperfine structure of the S states of muonic tritium

    Science.gov (United States)

    Martynenko, A. P.; Martynenko, F. A.; Faustov, R. N.

    2017-06-01

    The hyperfine structure of the energy spectrum of the S levels of muonic tritium has been calculated using the quasi-potential method in quantum electrodynamics (QED). The α5- and α6-order effects on the polarization of vacuum, the structure and recoil of the nucleus, and relativistic corrections have been taken into account. The obtained numerical values of hyperfine splittings of 239.819 meV (1S state) and 29.965 meV (2 S state) can be treated as reliable estimates for comparing with future experimental data of the CREMA collaboration, and hyperfine structure interval Δ12 = 8Δ E hfs (2 S)-Δ E hfs (1 S) =-0.100 meV can be used for verifying the QED predictions. The resultant precision values of hyperfine splitting are also important for calculating the rates of formation of (μ dt) mesomolecules in muonic catalysis reactions.

  14. The hyperfine Paschen-Back Faraday effect

    CERN Document Server

    Zentile, Mark A; Weller, Lee; Knappe, Svenja; Adams, Charles S; Hughes, Ifan G

    2014-01-01

    We investigate experimentally and theoretically the Faraday effect in an atomic medium in the hyperfine Paschen-Back regime, where the Zeeman interaction is larger than the hyperfine splitting. We use a small permanent magnet and a micro-fabricated vapour cell, giving magnetic fields of the order of a Tesla. We show that for low absorption and small rotation angles, the refractive index is well approximated by the Faraday rotation signal, giving a simple way to measure the atomic refractive index. Fitting to the atomic spectra, we achieve magnetic field sensitivity at the $10^{-4}$ level. Finally we note that the Faraday signal shows zero crossings which can be used as temperature insensitive error signals for laser frequency stabilisation at large detuning. The theoretical sensitivity for $^{87}$Rb is found to be $\\sim 40$ kHz/$^\\circ$C.

  15. The hyperfine Paschen-Back Faraday effect

    Science.gov (United States)

    Zentile, Mark A.; Andrews, Rebecca; Weller, Lee; Knappe, Svenja; Adams, Charles S.; Hughes, Ifan G.

    2014-04-01

    We investigate experimentally and theoretically the Faraday effect in an atomic medium in the hyperfine Paschen-Back regime, where the Zeeman interaction is larger than the hyperfine splitting. We use a small permanent magnet and a micro-fabricated vapour cell, giving magnetic fields of the order of a tesla. We show that for low absorption and small rotation angles, the refractive index is well approximated by the Faraday rotation signal, giving a simple way to measure the atomic refractive index. Fitting to the atomic spectra, we achieve magnetic field sensitivity at the 10-4 level. Finally we note that the Faraday signal shows zero crossings which can be used as temperature insensitive error signals for laser frequency stabilization at large detuning. The theoretical sensitivity for 87Rb is found to be ˜40 kHz °C-1.

  16. Modeling molecular hyperfine line emission

    CERN Document Server

    Keto, Eric

    2010-01-01

    In this paper we discuss two approximate methods previously suggested for modeling hyperfine spectral line emission for molecules whose collisional transitions rates between hyperfine levels are unknown. Hyperfine structure is seen in the rotational spectra of many commonly observed molecules such as HCN, HNC, NH3, N2H+, and C17O. The intensities of these spectral lines can be modeled by numerical techniques such as Lambda-iteration that alternately solve the equations of statistical equilibrium and the equation of radiative transfer. However, these calculations require knowledge of both the radiative and collisional rates for all transitions. For most commonly observed radio frequency spectral lines, only the net collisional rates between rotational levels are known. For such cases, two approximate methods have been suggested. The first method, hyperfine statistical equilibrium (HSE), distributes the hyperfine level populations according to their statistical weight, but allows the population of the rotationa...

  17. Tree-level split helicity amplitudes in ambitwistor space

    Science.gov (United States)

    Chen, Bin; Wu, Jun-Bao

    2009-12-01

    We study all tree-level split helicity gluon amplitudes by using the recently proposed Britto-Cachazo-Feng-Witten recursion relation and Hodges diagrams in ambitwistor space. We pick out the contributing diagrams and find that all of them can be divided into triangles in a suitable way. We give the explicit expressions for all of these amplitudes. As an example, we reproduce the six-gluon split next-to-maximally-helicity-violating amplitudes in momentum space.

  18. Observation of the hyperfine spectrum of antihydrogen

    Science.gov (United States)

    Ahmadi, M.; Alves, B. X. R.; Baker, C. J.; Bertsche, W.; Butler, E.; Capra, A.; Carruth, C.; Cesar, C. L.; Charlton, M.; Cohen, S.; Collister, R.; Eriksson, S.; Evans, A.; Evetts, N.; Fajans, J.; Friesen, T.; Fujiwara, M. C.; Gill, D. R.; Gutierrez, A.; Hangst, J. S.; Hardy, W. N.; Hayden, M. E.; Isaac, C. A.; Ishida, A.; Johnson, M. A.; Jones, S. A.; Jonsell, S.; Kurchaninov, L.; Madsen, N.; Mathers, M.; Maxwell, D.; McKenna, J. T. K.; Menary, S.; Michan, J. M.; Momose, T.; Munich, J. J.; Nolan, P.; Olchanski, K.; Olin, A.; Pusa, P.; Rasmussen, C. Ø.; Robicheaux, F.; Sacramento, R. L.; Sameed, M.; Sarid, E.; Silveira, D. M.; Stracka, S.; Stutter, G.; So, C.; Tharp, T. D.; Thompson, J. E.; Thompson, R. I.; van der Werf, D. P.; Wurtele, J. S.

    2017-08-01

    The observation of hyperfine structure in atomic hydrogen by Rabi and co-workers and the measurement of the zero-field ground-state splitting at the level of seven parts in 1013 are important achievements of mid-twentieth-century physics. The work that led to these achievements also provided the first evidence for the anomalous magnetic moment of the electron, inspired Schwinger’s relativistic theory of quantum electrodynamics and gave rise to the hydrogen maser, which is a critical component of modern navigation, geo-positioning and very-long-baseline interferometry systems. Research at the Antiproton Decelerator at CERN by the ALPHA collaboration extends these enquiries into the antimatter sector. Recently, tools have been developed that enable studies of the hyperfine structure of antihydrogen—the antimatter counterpart of hydrogen. The goal of such studies is to search for any differences that might exist between this archetypal pair of atoms, and thereby to test the fundamental principles on which quantum field theory is constructed. Magnetic trapping of antihydrogen atoms provides a means of studying them by combining electromagnetic interaction with detection techniques that are unique to antimatter. Here we report the results of a microwave spectroscopy experiment in which we probe the response of antihydrogen over a controlled range of frequencies. The data reveal clear and distinct signatures of two allowed transitions, from which we obtain a direct, magnetic-field-independent measurement of the hyperfine splitting. From a set of trials involving 194 detected atoms, we determine a splitting of 1,420.4 ± 0.5 megahertz, consistent with expectations for atomic hydrogen at the level of four parts in 104. This observation of the detailed behaviour of a quantum transition in an atom of antihydrogen exemplifies tests of fundamental symmetries such as charge-parity-time in antimatter, and the techniques developed here will enable more-precise such tests.

  19. Hyperfine rather than spin splittings dominate the fine structure of the B {sup 4}Σ{sup −}–X {sup 4}Σ{sup −} bands of AlC

    Energy Technology Data Exchange (ETDEWEB)

    Clouthier, Dennis J., E-mail: dclaser@uky.edu; Kalume, Aimable [Department of Chemistry, University of Kentucky, Lexington, Kentucky 40506-0055 (United States)

    2016-01-21

    Laser-induced fluorescence and wavelength resolved emission spectra of the B {sup 4}Σ{sup −}–X {sup 4}Σ{sup −} band system of the gas phase cold aluminum carbide free radical have been obtained using the pulsed discharge jet technique. The radical was produced by electron bombardment of a precursor mixture of trimethylaluminum in high pressure argon. High resolution spectra show that each rotational line of the 0-0 and 1-1 bands of AlC is split into at least three components, with very similar splittings and intensities in both the P- and R-branches. The observed structure was reproduced by assuming b{sub βS} magnetic hyperfine coupling in the excited state, due to a substantial Fermi contact interaction of the unpaired electron in the aluminum 3s orbital. Rotational analysis has yielded ground and excited state equilibrium bond lengths in good agreement with the literature and our own ab initio values. Small discrepancies in the calculated intensities of the hyperfine lines suggest that the upper state spin-spin constant λ′ is of the order of ≈0.025–0.030 cm{sup −1}.

  20. Multi-configuration Dirac-Hartree-Fock calculations of excitation energies, oscillator strengths and hyperfine structure constants for low-lying levels of Sm I

    CERN Document Server

    Zhou, Fuyang; Li, Jiguang; Wang, Jianguo

    2015-01-01

    The multi-configuration Dirac-Hartree-Fock method was employed to calculate the total and excitation energies, oscillator strengths and hyperfine structure constants for low-lying levels of Sm I. In the first-order perturbation approximation, we systematically analyzed correlation effects from each electrons and electron pairs. It was found that the core correlations are of importance for physical quantities concerned. Based on the analysis, the important configuration state wave functions were selected to constitute atomic state wave functions. By using this computational model, our excitation energies, oscillator strengths, and hyperfine structure constants are in better agreement with experimental values than earlier theoretical works.

  1. Level of the Subscapularis Split During Arthroscopic Latarjet.

    Science.gov (United States)

    Lädermann, Alexandre; Denard, Patrick J; Arrigoni, Paolo; Narbona, Pablo; Burkhart, Stephen S; Barth, Johannes

    2017-08-16

    To determine the location of the subscapularis split during arthroscopic Latarjet created by an inside-out technique passing a switching stick from the posterior portal across the glenohumeral joint. An inside-out technique was used to arthroscopically create a subscapularis split in 20 fresh-frozen human cadaveric shoulders. The distance between the exit point of the switching stick and the upper border of the subscapularis and the anterior circumflex vessels was measured arthroscopically and after open dissection. Twelve splits were in the upper third of the subscapularis, 3 were at the junction of the upper third and the middle third, and 5 were in the middle third. None were at the junction between the middle and lower third as desired. Using the inside-out method during arthroscopic Latarjet may produce a high subscapularis split if it is performed from with a switching stick that is inserted through the posterior approach, and passed across the glenohumeral joint at the level of the inferior glenoid. This study analyzed the relative risk of high subscapularis split during the arthroscopic Latarjet procedure. Copyright © 2017 Arthroscopy Association of North America. Published by Elsevier Inc. All rights reserved.

  2. Hyperfine structure in photoassociative spectra of 6Li2 and 7Li2

    NARCIS (Netherlands)

    Abraham, E.R.I.; McAlexander, W.I.; Stoof, H.T.C.; Hulet, R.G.

    1996-01-01

    We present spectra of hyperfine resolved vibrational levels of the A1Σu+and 1 3Σg+ states of 6Li2 and 7Li2 obtained via photoassociation of colliding ultracold atoms in a magneto-optical trap. A simple first-order perturbation theory analysis accurately accounts for the frequency splittings and rela

  3. Observation of hyperfine interaction in photoassociation spectra of ultracold RbYb

    Science.gov (United States)

    Bruni, C.; Görlitz, A.

    2016-08-01

    We report on the creation of ultracold heteronuclear and electronically excited Rb*Yb molecules in a hybrid conservative trap by photoassociation of ultracold 87Rb and 176Yb. The molecules are formed below the Rb5 p 1(1/2 2P)+Yb6 s 2(S10) dissociation limit and the resonances are detected using trap-loss spectroscopy. By addressing vibrational levels with binding energies down to EB=-h ×2.2 THz , we study the change in hyperfine coupling of the diatomic molecule as a function of internuclear separation. We observe a decreasing hyperfine splitting for more tightly bound excited molecular states where the hyperfine splitting is reduced by more than 30 % compared to the atomic value for 87Rb.

  4. The hyperfine Paschen-Back Faraday effect

    OpenAIRE

    Zentile, Mark A.; Andrews, Rebecca; Weller, Lee; Knappe, Svenja; Adams, Charles S.; Hughes, Ifan G

    2014-01-01

    We investigate experimentally and theoretically the Faraday effect in an atomic medium in the hyperfine Paschen-Back regime, where the Zeeman interaction is larger than the hyperfine splitting. We use a small permanent magnet and a micro-fabricated vapour cell, giving magnetic fields of the order of a Tesla. We show that for low absorption and small rotation angles, the refractive index is well approximated by the Faraday rotation signal, giving a simple way to measure the atomic refractive i...

  5. Abundances of Mn, Co and Eu in a sample of 20 F-G disk stars: the influence of hyperfine structure splitting

    CERN Document Server

    Peloso, E F; Silva, L; De Mello, G F P

    2005-01-01

    We present Mn, Co and Eu abundances for a sample of 20 disk F and G dwarfs and subgiants with metallicities in the range -0.8 <= [Fe/H] <= +0.3. We investigate the influence of hyperfine structure (HFS) on the derived abundances of Mn and Co by using HFS data from different sources in the literature, as well as calculated HFS from interaction factors A and B. Eu abundances were obtained from spectral synthesis of one Eu II line that takes into account HFS from a series of recent laboratory measurements. For the lines analyzed in this study, we find that for manganese, the differences between abundances obtained with different HFSs are no larger than 0.10 dex. Our cobalt abundances are even less sensitive to the choice of HFS than Mn, presenting a 0.07 dex maximum difference between determinations with different HFSs. However, the cobalt HFS data from different sources are significantly different. Our abundance results for Mn offer an independent confirmation of the results from Prochaska & McWilliam...

  6. Effective hyperfine temperature in frustrated Gd 2Sn 2O 7: two level model and 155Gd Mössbauer measurements

    Science.gov (United States)

    Bertin, E.; Bonville, P.; Bouchaud, J.-P.; Hodges, J. A.; Sanchez, J. P.; Vulliet, P.

    2002-06-01

    Using 155Gd Mössbauer spectroscopy down to 27 mK, we show that, in the geometrically frustrated pyrochlore Gd2Sn2O7, the Gd3+ hyperfine levels are populated out of equilibrium. From this, we deduce that the hyperfine field, and the correlated Gd3+ moments which produce this field, continue to fluctuate as T|--> 0. With a model of a spin 1/2 system experiencing a magnetic field which reverses randomly in time, we obtain an analytical expression for the steady state probability distribution of the level populations. This distribution is a simple function of the ratio of the nuclear spin relaxation time to the average electronic spin-flip time. In Gd2Sn2O7, we find the two time scales are of the same order of magnitude. We discuss the mechanism giving rise to the nuclear spin relaxation and the influence of the electronic spin fluctuations on the hyperfine specific heat. The corresponding low temperature measurements in Gd2Ti2O7 are presented and discussed.

  7. Atom-interferometric measurement of Stark level splittings

    CERN Document Server

    Wang, Limei; Zhang, Linjie; Raithel, Georg; Zhao, Jianming; Jia, Suotang

    2015-01-01

    Multiple adiabatic/diabatic passages through avoided crossings in the Stark map of cesium Rydberg atoms are employed as beam splitters and recombiners in an atom-interferometric measurement of energy-level splittings. We subject cold cesium atoms to laser-excitation, electric-field and detection sequences that constitute an (internal-state) atom interferometer. For the read-out of the interferometer we utilize state-dependent collisions, which selectively remove atoms of one kind from the detected signal. We investigate the dependence of the interferometric signal on timing and field parameters, and find good agreement with time-dependent quantum simulations of the interferometer. Fourier analysis of the interferometric signals yield coherence frequencies that agree with corresponding energy-level differences in calculated Stark maps. The method enables spectroscopy of states that are inaccessible to direct laser-spectroscopic observation, due to selection rules, and has applications in field metrology.

  8. Lamb shifts and hyperfine structure in 6Li+ and 7Li+: Theory and experiment

    DEFF Research Database (Denmark)

    Riis, E.; Sinclair, A. G.; Poulsen, Ove;

    1994-01-01

    High-precision laser-resonance measurements accurate to +/-0.5 MHz, or better are reported for transitions among the 1s2s S-3(1)-1s2p P-3(J) hyperfine manifolds for each of J = 0, 1, and 2 in both Li-6(+) and Li-7(+). A detailed analysis of hyperfine structure is performed for both the S and P...... states, using newly calculated values for the magnetic dipole and electric quadrupole coupling constants, and the hyperfine shifts subtracted from the measurements. The resulting transition frequencies are then analysed on three different levels. First, the isotope shifts in the fine-structure splittings....... The accuracy of 11 parts per million is the best two-electron Lamb shift measurement in the literature, and is comparable to the accuracies achieved in hydrogen. Theoretical contributions to the two-electron Lamb shift are discussed, including terms of order (alpha Z)(4) recently obtained by Chen, Cheng...

  9. Computation of hyperfine energies of hydrogen, deuterium and tritium quantum dots

    Energy Technology Data Exchange (ETDEWEB)

    Çakır, Bekir, E-mail: bcakir@selcuk.edu.tr [Physics Department, Faculty of Science, Selcuk University, Campus 42075, Konya (Turkey); Özmen, Ayhan [Physics Department, Faculty of Science, Selcuk University, Campus 42075, Konya (Turkey); Yakar, Yusuf, E-mail: yuyakar@yahoo.com [Physics Department, Faculty of Arts and Science, Aksaray University, Campus 68100, Aksaray (Turkey)

    2016-01-15

    The hyperfine energies and hyperfine constants of the ground and excited states of hydrogen, deuterium and tritium quantum dots(QDs) are calculated. Quantum genetic algorithm (QGA) and Hartree–Fock–Roothaan (HFR) methods are employed to calculate the unperturbed wave functions and energy eigenvalues. The results show that in the medium and strong confinement regions the hyperfine energy and hyperfine constant are strongly affected by dot radius, impurity charge, electron spin orientation, impurity spin and impurity magnetic moment. Besides, in all dot radii, the hyperfine splitting and hyperfine constant of the confined hydrogen and tritium atoms are approximately equivalent to each other and they are greater than the confined deuterium atom.

  10. Computation of hyperfine energies of hydrogen, deuterium and tritium quantum dots

    Science.gov (United States)

    Çakır, Bekir; Özmen, Ayhan; Yakar, Yusuf

    2016-01-01

    The hyperfine energies and hyperfine constants of the ground and excited states of hydrogen, deuterium and tritium quantum dots(QDs) are calculated. Quantum genetic algorithm (QGA) and Hartree-Fock-Roothaan (HFR) methods are employed to calculate the unperturbed wave functions and energy eigenvalues. The results show that in the medium and strong confinement regions the hyperfine energy and hyperfine constant are strongly affected by dot radius, impurity charge, electron spin orientation, impurity spin and impurity magnetic moment. Besides, in all dot radii, the hyperfine splitting and hyperfine constant of the confined hydrogen and tritium atoms are approximately equivalent to each other and they are greater than the confined deuterium atom.

  11. Hyperfine structure of S-states of muonic tritium

    Directory of Open Access Journals (Sweden)

    Martynenko F.A.

    2017-01-01

    Full Text Available On the basis of quasipotential method in quantum electrodynamics we carry out a precise calculation of hyperfine splitting of S-states in muonic tritium. The one-loop and two-loop vacuum polarization corrections, relativistic effects, nuclear structure corrections in first and second orders of perturbation theory are taken into account. The contributions to hyperfine structure are obtained in integral form and calculated analytically and numerically. Obtained results for hyperfine splitting can be used for a comparison with future experimental data of CREMA collaboration.

  12. Coulomb impurity effects on the zero-Landau level splitting of graphene on polar substrates

    Science.gov (United States)

    Xiao, Yao; Li, Wei-Ping; Li, Zhi-Qing; Wang, Zi-Wu

    2017-04-01

    We theoretically investigate the effects of the Coulomb impurity on the zero-Landau level splitting of graphene on different polar substrates basing on the Fröhlich polaron model, in which the polaron is formed due to the carriers-surface optical phonon coupling. We discuss the influence of Coulomb impurity on the zero-Landau level splitting in the case of weak and strong coupling limits. We find that the splitting energy can be varied in a large scale due to the Coulomb impurity, which provides the possible theoretical explanation for the experimental measurements regarding the energy gap opened and zero-Landau level splitting in Landau quantized graphene.

  13. Observation and analysis of the hyperfine structure of near-dissociation levels of the NaCs c +3Σ state below the dissociation limit 3 S1 /2+6 P3 /2

    Science.gov (United States)

    Liu, Wenliang; Wu, Jizhou; Ma, Jie; Li, Peng; Sovkov, Vladimir B.; Xiao, Liantuan; Jia, Suotang

    2016-09-01

    We report photoassociation (PA) of ultracold Na and Cs atoms in a dual-species magneto-optical trap. Trap loss spectroscopy of the ultracold polar NaCs molecules formed by PA, which carries information about relative PA transition strengths, has been experimentally obtained by using highly sensitive modulation spectroscopy technique. The fine and hyperfine effects at near-dissociation levels of NaCs molecular c +3Σ state are observed and modeled. The interaction Hamiltonian is described in terms of the Hund's case (a ) coupling scheme. The molecular hyperfine structure of near-dissociation levels is simulated within a simplified model of four interacting vibrational levels belonging to different initially unperturbed electronic states. The results of the simulation infer that the interaction parameters of the observed near-dissociation levels are close to the asymptotic parameters of the pair of atoms. The coupling of the electronic states is essential for forming the hyperfine structure.

  14. Hyperfine interaction in Co{sub 2}SiO{sub 4} investigated by high resolution neutron spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Chatterji, Tapan, E-mail: chatterji@ill.f [JCNS, Forschungszentrum Juelich Outstation at Institut Laue-Langevin, B.P. 156, 38042 Grenoble Cedex 9 (France); Wuttke, J. [JCNS, Forschungszentrum Juelich Outstation at FRMII, Lichtenbergstrasse 1, 85747 Garching (Germany); Sazonov, A.P. [FRMII, Technische Universitaet Muenchen, Lichtenbergstrasse 1, 85747 Garching (Germany)

    2010-10-15

    We have investigated the hyperfine interaction in Co{sub 2}SiO{sub 4} by inelastic neutron scattering with a high resolution back-scattering neutron spectrometer. The energy spectrum measured from a Co{sub 2}SiO{sub 4} powder sample revealed inelastic peaks at E=1.387{+-}0.006{mu}eV at T=3.5 K on both energy gain and energy loss sides. The inelastic peaks move gradually towards lower energy with increasing temperature and finally merge with the elastic peak at the electronic magnetic ordering temperature T{sub N{approx}}50K. The inelastic peaks have been interpreted to be due to the transition between hyperfine-split nuclear level of the {sup 59}Co isotopes with spin I=7/2 . The temperature dependence of the energy of the inelastic peak in Co{sub 2}SiO{sub 4} showed that this energy can be considered to be the order parameter of the antiferromagnetic phase transition. The determined hyperfine splitting in Co{sub 2}SiO{sub 4} deviates from the linear relationship between the ordered electronic magnetic moment and the hyperfine splitting in Co, Co-P amorphous alloys and CoO presumably due to the presence of unquenched orbital moment. These results are very similar to those of CoF{sub 2} recently reported by Chatterji and Schneider.

  15. Experimental investigation of the hyperfine spectra of Pr I-lines: Discovery of new fine structure levels with high angular momentum

    Science.gov (United States)

    Siddiqui, Imran; Khan, Shamim; Windholz, Laurentius

    2014-05-01

    We present 66 even and 58 odd parity newly discovered fine structure levels of Pr I with high angular momentum: J = 15/2, 17/2 and 19/2 and 21/2. Spectral lines in the range 4200 Å to 7500 Å were experimentally investigated using laser induced fluorescence spectroscopy in a hollow cathode discharge lamp. The levels were discovered by analysis of the recorded hyperfine patterns of the investigated transitions. More than 800 spectral lines could be classified with help of these levels. Supplementary material in the form of one pdf file available from the Journal web page at http://dx.doi.org/10.1140/epjd/e2014-50025-7

  16. Hyperfine structure constants and isotope shift of the levels of the configuration 4 f 6 5 d 6 s 2 in Eu I

    Science.gov (United States)

    Elantkowska, M.; Bernard, A.; Dembczyński, J.; Ruczkowski, J.

    1993-06-01

    The hyperfine structure (hfs) and the isotope shift (IS) of transitions between metastable levels of the configuration 4 f 7 5 d 6 s and levels of the configuration 4 f 6 5 d 6 s 2 of151Eu and153Eu were studied by means of the high resolution laser-atomic-beam technique. New data for the hfs in151Eu and153Eu were obtained as well as new and more accurate for the IS between151Eu and153Eu. The measured hfs constants A and B of the 4 f 6 5 d 6 s 2 configuration allow to perform a parametric analysis using the Sandars and Beck theory. The value of the Sternheimer correction is also disscused.

  17. Relativistic many-body calculations of energy levels, hyperfine constants, electric-dipole matrix elements and static polarizabilities for alkali-metal atoms

    CERN Document Server

    Safronova, M S; Derevianko, S A

    1999-01-01

    Removal energies and hyperfine constants of the lowest four $ns, np_{1/2}$ and $np_{3/2}$ states in Na, K, Rb and Cs are calculated; removal energies of the n=7--10 states and hyperfine constants of the n=7 and 8 states in Fr are also calculated. The calculations are based on the relativistic single-double (SD) approximation in which single and double excitations of Dirac-Hartree-Fock (DHF) wave functions are included to all-orders in perturbation theory. Using SD wave functions, accurate values of removal energies, electric-dipole matrix elements and static polarizabilities are obtained, however, SD wave functions give poor values of magnetic-dipole hyperfine constants for heavy atoms. To obtain accurate values of hyperfine constants for heavy atoms, we include triple excitations partially in the wave functions. The present calculations provide the basis for reevaluating PNC amplitudes in Cs and Fr.

  18. Hyperfine structure of the 6d{sup 2}D{sub 3/2} level in trapped short-lived {sup 211,} {sup 209}Ra{sup +} ions

    Energy Technology Data Exchange (ETDEWEB)

    Versolato, O.O., E-mail: versolato@kvi.nl [University of Groningen, Kernfysisch Versneller Instituut, NL-9747 AA Groningen (Netherlands); Giri, G.S.; Berg, J.E. van den; Boell, O.; Dammalapati, U.; Hoek, D.J. van der; Hoekstra, S.; Jungmann, K.; Kruithof, W.L.; Mueller, S.; Nunez Portela, M.; Onderwater, C.J.G.; Santra, B.; Timmermans, R.G.E.; Wansbeek, L.W.; Willmann, L.; Wilschut, H.W. [University of Groningen, Kernfysisch Versneller Instituut, NL-9747 AA Groningen (Netherlands)

    2011-08-15

    The hyperfine structure of short-lived trapped {sup 211,209}Ra{sup +} ions was investigated by means of laser spectroscopy. The hyperfine structure constants A and B of the 6d{sup 2}D{sub 3/2} level were determined. There is a 2.2 standard deviation difference between the theoretical and the more accurate experimental value for the B coefficient of {sup 211}Ra{sup +}. These measurements provide a test for the atomic theory required for upcoming experiments on atomic parity violation and atomic clocks. -- Highlights: → The hyperfine structure of trapped {sup 211,} {sup 209}Ra{sup +} was studied with laser spectroscopy. → The hyperfine structure constants A and B of the 6d{sup 2}D{sub 3/2} level were determined. → A 2.2σ difference with theory is found for the B coefficient of {sup 211}Ra{sup +}. → These measurements test atomic theory, needed in atomic parity violation experiments.

  19. The Level-split of the Two-level Entangled Atom in an Optical Field

    Institute of Scientific and Technical Information of China (English)

    CAO Zhuoliang; HUANG Ting; GUO Guangcan; YI Youming

    2002-01-01

    The behavior of a two-level entangled atom in an optical field with circular polarization is studied in this paper. The interaction of an optical field and one of the entangled atoms is analyzed in detail. A general solution of the SchrAo¨Gdinger equation about the motion of the entangled atom is obtained. The properties of the action are dependent on the initial state of the atom. By detecting the entangled atom out of the field, we can obtain the state of the other atom moving in the field. It is shown that the state of the atom out of the field will influence the energies of the split-levels of the atom in the field.

  20. Observation of molecular hyperfine structure in the extreme ultraviolet: The HF C-X spectrum

    NARCIS (Netherlands)

    Philippson, J.N.; Shiell, R.C.; Reinhold, E.M.; Ubachs, W.M.G.

    2008-01-01

    Clearly resolved hyperfine structure has been observed in the extreme ultraviolet (XUV) spectra of the C (1)Pi, v=0-X (1)Sigma(+), v=0 transition of (HF)-F-19 obtained through 1 XUV+1 UV resonance enhanced multiphoton ionization spectroscopy. The hyperfine splitting within the R-branch lines shows

  1. Spin-orbital interaction of photons and fine splitting of levels in ring dielectric resonator

    CERN Document Server

    Bliokh, K Y

    2004-01-01

    We consider eigen modes of a ring resonator made of a circular dielectric waveguide. Taking into account the polarization corrections, which are responsible for the interaction of polarization and orbital properties of electromagnetic waves (spin-orbital interaction of photons), results in fine splitting of the levels of scalar approximation. The basic features of this fine structure of the levels are quite similar to that of electron levels in an atom. Namely: 1) sublevels of the fine structure are defined by an additional quantum number: product of helicity of the wave and its orbital moment; 2) each level of the scalar approximation splits into N sublevels (N is the principal quantum number); 3) each level of the fine structure remains twice degenerated due to local axial symmetry of the waveguide. Numerical estimations show that the described fine splitting of levels may be observed in optic-fiber ring resonators.

  2. Probing an Excited-State Atomic Transition Using Hyperfine Quantum Beat Spectroscopy

    CERN Document Server

    Wade, Christopher G; Keaveney, James; Adams, Charles S; Weatherill, Kevin J

    2014-01-01

    We describe a method to observe the dynamics of an excited-state transition in a room temperature atomic vapor using hyperfine quantum beats. Our experiment using cesium atoms consists of a pulsed excitation of the D2 transition, and continuous-wave driving of an excited-state transition from the 6P$_{3/2}$ state to the 7S$_{1/2}$ state. We observe quantum beats in the fluorescence from the 6P$_{3/2}$ state which are modified by the driving of the excited-state transition. The Fourier spectrum of the beat signal yields evidence of Autler-Townes splitting of the 6P$_{3/2}$, F = 5 hyperfine level and Rabi oscillations on the excited-state transition. A detailed model provides qualitative agreement with the data, giving insight to the physical processes involved.

  3. Multiconfiguration Dirac-Hartree-Fock energy levels, oscillator strengths, transition probabilities, hyperfine constants and Landé g-factor of intermediate Rydberg series in neutral argon atom

    Science.gov (United States)

    Salah, Wa'el; Hassouneh, Ola

    2017-04-01

    We computed the energy levels, oscillator strengths f_{ij}, the radiative transition rates A_{ij}, the Landé g -factor, the magnetic dipole moment and the electric quadrupole hyperfine constants of the intermediate Rydberg series ns [k]J ( 4 ≤ n ≤ 6), nd [k]J (3 ≤ n ≤ 4), np [k]J (4 ≤ n ≤ 5) relative to the ground state 3p6 1S0 for neutral argon atom spectra. The values are obtained in the framework of the multiconfiguration Dirac-Hartree-Fock (MCDHF) approach. In this approach, Breit interaction, leading quantum electrodynamics (QED) effects and self-energy correction are taken into account. Moreover, these spectroscopic parameters have been calculated for many levels belonging to the configuration 3p54s, 3p55s, 3p56s, 3p53d, 3p54d, 3p54p, 3p55p as well as for transitions between levels 3p54s-3p54p, 3p54p-3p53d, 3p54p-3p55s, 3p55s-3p55p and 3p55p-3p56s. The large majority of the lines from the 4p-5s and 4p-3d, 5s-5p and 5p-6s transition arrays have been observed and the calculations are consistent with the J -file-sum rule. The obtained theoretical values are compared with previous experimental and theoretical data available in the literature. An overall satisfactory agreement is noticed allowing assessing the reliability of our data.

  4. Full hyperfine structure analysis of singly ionized molybdenum

    Science.gov (United States)

    Bouazza, Safa

    2017-03-01

    For a first time a parametric study of hyperfine structure of Mo II configuration levels is presented. The newly measured A and B hyperfine structure (hfs) constants values of Mo II 4d5, 4d45s and 4d35s2 configuration levels, for both 95 and 97 isotopes, using Fast-ion-beam laser-induced fluorescence spectroscopy [1] are gathered with other few data available in literature. A fitting procedure of an isolated set of these three lowest even-parity configuration levels has been performed by taking into account second-order of perturbation theory including the effects of closed shell-open shell excitations. Moreover the same study was done for Mo II odd-parity levels; for both parities two sets of fine structure parameters as well as the leading eigenvector percentages of levels and Landé-factor gJ, relevant for this paper are given. We present also predicted singlet, triplet and quintet positions of missing experimental levels up to 85000 cm-1. The single-electron hfs parameter values were extracted in their entirety for 97Mo II and for 95Mo II: for instance for 95Mo II, a4d01 =-133.37 MHz and a5p01 =-160.25 MHz for 4d45p; a4d01 =-140.84 MHz, a5p01 =-170.18 MHz and a5s10 =-2898 MHz for 4d35s5p; a5s10 =-2529 (2) MHz and a4d01 =-135.17 (0.44) MHz for the 4d45s. These parameter values were analysed and compared with diverse ab-initio calculations. We closed this work with giving predicted values of magnetic dipole and electric quadrupole hfs constants of all known levels, whose splitting are not yet measured.

  5. Hyperfine-structure study of the 3d10 5p 2P3/2 level of neutral copper using pulsed level-crossing spectroscopy at short laser wavelengths

    Science.gov (United States)

    Bengtsson, J.; Larsson, J.; Svanberg, S.; Wahlstrom, C.-G.

    1990-01-01

    A hyperfine-structure study of the strongly perturbed 3d10 5p 2P3/2 state of neutral copper was performed using pulsed level-crossing spectroscopy. Excitation was accomplished at the short wavelength of 202 nm, where intense laser pulses were obtained using frequency tripling of dye laser radiation. For Cu-63, a = 61.7(9) MHz, b = 4.9(7) MHz, and tau = 25,5(10) ns were obtained for the magnetic dipole and the electric quadrupoles interaction constants and the lifetime, respectively. A comparison with theoretical calculations based on the multiconfiguration Hartree-Fock method is made. A discussion of the usefulness of level-crossing, quantum-beat, and radio-frequency techniques for high-resolution spectroscopy at wavelengths in the UV and vacuum-UV region is presented.

  6. The NH$_2$D hyperfine structure revealed by astrophysical observations

    CERN Document Server

    Daniel, F; Punanova, A; Harju, J; Faure, A; Roueff, E; Sipilä, O; Caselli, P; Güsten, R; Pon, A; Pineda, J E

    2016-01-01

    The 1$_{11}$-1$_{01}$ lines of ortho and para--NH$_2$D (o/p-NH$_2$D), respectively at 86 and 110 GHz, are commonly observed to provide constraints on the deuterium fractionation in the interstellar medium. In cold regions, the hyperfine structure due to the nitrogen ($^{14}$N) nucleus is resolved. To date, this splitting is the only one which is taken into account in the NH$_2$D column density estimates. We investigate how the inclusion of the hyperfine splitting caused by the deuterium (D) nucleus affects the analysis of the rotational lines of NH$_2$D. We present 30m IRAM observations of the above mentioned lines, as well as APEX o/p-NH$_2$D observations of the 1$_{01}$-0$_{00}$ lines at 333 GHz. The hyperfine spectra are first analyzed with a line list that only includes the hyperfine splitting due to the $^{14}$N nucleus. We find inconsistencies between the line widths of the 1$_{01}$-0$_{00}$ and 1$_{11}$-1$_{01}$ lines, the latter being larger by a factor of $\\sim$1.6$\\pm0.3$. Such a large difference is...

  7. Quadrupole Splittings in the near-infrared spectrum of $^{14}$NH$_3$

    CERN Document Server

    Twagirayezu, Sylvestre; Sears, Trevor J

    2016-01-01

    Sub-Doppler, saturation dip, spectra of lines in the $v_1 + v_3$, $v_1 + 2v_4$ and $v_3 + 2v_4$ bands of $^{14}$NH$_3$ have been measured by frequency comb-referenced diode laser absorption spectroscopy. The observed spectral line widths are dominated by transit time broadening, but show resolved or partially-resolved hyperfine splittings that are primarily determined by the $^{14}$N quadrupole coupling. Modeling of the observed line shapes based on the known hyperfine level structure of the ground state of the molecule shows that, in nearly all cases, the excited state level has hyperfine splittings similar to the same rotational level in the ground state. The data provide accurate frequencies for the line positions and easily separate lines overlapped in Doppler-limited spectra. The observed hyperfine splittings can be used to make and confirm rotational assignments and ground state combination differences obtained from the measured frequencies are comparable in accuracy to those obtained from conventional ...

  8. Hyperfine structure of P-states in muonic deuterium

    CERN Document Server

    Faustov, R N; Martynenko, G A; Sorokin, V V

    2015-01-01

    On the basis of quasipotential approach to the bound state problem in quantum electrodynamics we calculate hyperfine structure intervals Delta E^{hfs}(2P_{1/2}) and Delta E^{hfs}(2P_{3/2}) for P-states in muonic deuterium. The tensor method of projection operators for the calculation of the hyperfine structure of P-states with definite quantum numbers of total atomic momentum F and total muon momentum j in muonic deuterium is formulated. We take into account vacuum polarization, relativistic, quadruple and structure corrections of orders alpha^4, alpha^5 and alpha^6. The obtained numerical values of hyperfine splittings are useful for the analysis of new experimental data of the CREMA collaboration regarding to muonic deuterium.

  9. Autler- Townes Splitting in Photoelectron Spectrum of Three-Level Li2 Molecule in Ultrashort Pulse Laser Fields

    Institute of Scientific and Technical Information of China (English)

    HU Wen-Hui; YUAN Kai-Jun; HAN Yong-Chang; Shu Chuang-Cun; CONG Shu-Lin

    2007-01-01

    The Autler-Townes (AT) splitting in femtosecond photoelectron spectrum of three-level Lii molecules is theoretically investigated using time-dependent quantum wave packet method. With proper femtosecond laser pulses, three peaks of the AT splitting can be observed in the photoelectron spectrum. The AT splitting stems from rapid Rabi oscillation caused by intense ultrashort laser pluses. The effects of laser parameters on the molecular ionization dynamics are also discussed.

  10. High-accuracy Complete Active Space multiconfiguration Dirac-Hartree-Fock calculations of hyperfine structure constants of the gold atom

    CERN Document Server

    Bierón, Jacek; Indelicato, Paul; Jönsson, Per; Pyykkö, Pekka

    2009-01-01

    The multiconfiguration Dirac-Hartree-Fock (MCDHF) model has been employed to calculate the expectation values for the hyperfine splittings of the 5d96s2 2D3/2 and 5d96s2 2D5/2 levels of atomic gold. One-, two-, and three-body electron correlation effects involving all 79 electrons have been included in a systematic manner. The approximation employed in this study is equivalent to a Complete Active Space (CAS) approach. Calculated electric field gradients, together with experimental values of the electric quadrupole hyperfine structure constants, allow us to extract a nuclear electric quadrupole moment Q(197Au)=521.5(5.0) mb.

  11. Landau level spectroscopy of Dirac electrons in a polar semiconductor with giant Rashba spin splitting.

    Science.gov (United States)

    Bordács, Sándor; Checkelsky, Joseph G; Murakawa, Hiroshi; Hwang, Harold Y; Tokura, Yoshinori

    2013-10-18

    Optical excitations of BiTeI with large Rashba spin splitting have been studied in an external magnetic field (B) applied parallel to the polar axis. A sequence of transitions between the Landau levels (LLs), whose energies are in proportion to √B were observed, being characteristic of massless Dirac electrons. The large separation energy between the LLs makes it possible to detect the strongest cyclotron resonance even at room temperature in moderate fields. Unlike in 2D Dirac systems, the magnetic field induced rearrangement of the conductivity spectrum is directly observed.

  12. High resolution spectroscopy of the Cs2 D 1Sigma u + -X 1Sigma g + transition and hyperfine structure

    Science.gov (United States)

    Kobayashi, Tooru; Usui, Takashi; Kumauchi, Takahiro; Baba, Masaaki; Ishikawa, Kiyoshi; Katô, Hajime

    1993-02-01

    The Doppler-free high resolution laser spectroscopy of Cs2 D 1Σu+-X 1Σg+ transition is extended up to v'=65. By comparing the spectral linewidth and the time-resolved fluorescence intensity, the line broadening observed for transitions to the D 1Σu+(v'=63,J'≤70) levels is identified as the lifetime broadening originating from the predissociation. Line splittings are observed for the D 1Σu+(v'=46,J'≥95)-X 1Σg+(v`= 1,J`) transitions and are identified as the hyperfine splitting due to a magnetic dipole interaction between nuclear spin and electron. The hyperfine splitting is attributed to mixing of the (2) 3Πu state, whose wave function changes from Hund's case (a) to case (b) at large J. The dependence of the electric dipole transition moment on the internuclear distance for the D 1Σu+-X 1Σg+ transition is determined by comparing the observed and calculated line intensities of the dispersed fluorescence.

  13. Paschen-Back effect involving atomic fine and hyperfine structure states

    Science.gov (United States)

    Sowmya, K.; Nagendra, K. N.; Sampoorna, M.; Stenflo, J. O.

    2015-10-01

    The linear polarization in spectral lines produced by coherent scattering is significantly modified by the quantum interference between the atomic states in the presence of a magnetic field. When magnetic fields produce a splitting which is of the order of or greater than the fine or hyperfine structure splittings, we enter the Paschen-Back effect (PBE) regime, in which the magnetic field dependence of the Zeeman splittings and transition amplitudes becomes non-linear. In general, PBE occurs for sufficiently strong fields when the fine structure states are involved and for weak fields in the case of hyperfine structure states. In this work, we apply the recently developed theory of PBE in the atomic fine and hyperfine structure states including the effects of partial frequency redistribution to the case of Li i 6708 Å doublet. We explore the signatures of PBE in a single scattering event and their applicability to the solar magnetic field diagnostics.

  14. The fine structure splitting of the level of lithium in Rydberg states

    Institute of Scientific and Technical Information of China (English)

    胡先权; 胡文江; 孔春阳

    2002-01-01

    The Hamiltonian of the four-body problem for a lithium atom is expanded in series. The level shift and levelformula of a lithium atom in Rydberg states are achieved by means of the calculation of polarization of the atomic core(including the contribution of dipole, quadrupole and octupole components). We also consider the effect of relativitytheory, the orbital angular momentum L and the spin angular momentum S coupling scheme (LS coupling) and high-order correction of the effective potential to the level shift. The fine structure splitting (N=5-12, L=4-9, J=L±l/2)and level intervals in B ydberg states have been calculated by the above-mentioned formula and compared with recentexperimental data.

  15. Landau Level Splittings, Phase Transitions, and Nonuniform Charge Distribution in Trilayer Graphene.

    Science.gov (United States)

    Campos, Leonardo C; Taychatanapat, Thiti; Serbyn, Maksym; Surakitbovorn, Kawin; Watanabe, Kenji; Taniguchi, Takashi; Abanin, Dmitry A; Jarillo-Herrero, Pablo

    2016-08-05

    We report on magnetotransport studies of dual-gated, Bernal-stacked trilayer graphene (TLG) encapsulated in boron nitride crystals. We observe a quantum Hall effect staircase which indicates a complete lifting of the 12-fold degeneracy of the zeroth Landau level. As a function of perpendicular electric field, our data exhibit a sequence of phase transitions between all integer quantum Hall states in the filling factor interval -8Landau level splittings and quantum Hall phase transitions can be understood within a single-particle picture, but imply the presence of a charge density imbalance between the inner and outer layers of TLG, even at charge neutrality and zero transverse electric field. Our results indicate the importance of a previously unaccounted band structure parameter which, together with a more accurate estimate of the other tight-binding parameters, results in a significantly improved determination of the electronic and Landau level structure of TLG.

  16. Experimental investigation of the hyperfine spectra of Pr I-lines: discovery of new fine structure energy levels of Pr I using LIF spectroscopy with medium angular momentum quantum number between 7/2 and 13/2

    Science.gov (United States)

    Siddiqui, Imran; Khan, Shamim; Windholz, Laurentius

    2016-03-01

    We present 39 even and 60 odd parity newly discovered fine structure levels of Pr I with angular momentum quantum numbers J = 7 / 2, 9/2, 11/2 and 13/2. Spectral lines in the wavelength range of 4200 Å to 7500 Å were investigated experimentally using laser-induced fluorescence spectroscopy or optogalvanic spectroscopy. Free Pr atoms were produced in a hollow cathode discharge. A high resolution Fourier transform spectrum of Pr was used to extract excitation wavelengths. From an analysis of the recorded hyperfine patterns, together with excitation and fluorescence wavelengths, we were able to find the unknown levels involved in the formation of the investigated lines. More than 500 spectral lines could be classified by the new levels. Supplementary material in the form of one pdf file available from the Journal web page at http://dx.doi.org/10.1140/epjd/e2016-60485-2

  17. Hyperfine spectroscopy of muonic hydrogen and the PSI Lamb shift experiment

    Energy Technology Data Exchange (ETDEWEB)

    Adamczak, Andrzej [Institute of Nuclear Physics, Polish Academy of Sciences, ul. Radzikowskiego 152, 31-342 Krakow (Poland); Bakalov, Dimitar, E-mail: dbakalov@inrne.bas.bg [Institute for Nuclear Research and Nuclear Energy, Bulgarian Academy of Sciences, Tsarigradsko chaussee 72, Sofia 1784 (Bulgaria); Stoychev, Lyubomir [Istituto Nazionale di Fisica Nucleare, Sezione di Trieste, Via A. Valerio 2, 34127 Trieste (Italy); The Abdus Salam International Centre for Theoretical Physics, Strada Costiera 11, 34014 Trieste (Italy); Vacchi, Andrea [Istituto Nazionale di Fisica Nucleare, Sezione di Trieste, Via A. Valerio 2, 34127 Trieste (Italy)

    2012-06-15

    The recent Lamb shift experiment at PSI and the discussions about the incompatibility of the proton radii extracted using different methods have revived the interest in the measurement of the hyperfine splitting of the ground state in muonic hydrogen. We summarize the existing experimental ideas for this measurement and analyze quantitatively the main methodological difficulties, expected to be related to the required power of the IR laser source, the signal-to-noise ratio and other systematic factors. An elaborate model is developed to estimate the statistical uncertainty of the experimental value of the hyperfine splitting.

  18. Multi-level Split Cord Malformation: Do We Need a New Classification?

    Directory of Open Access Journals (Sweden)

    Gmaan A Alzhrani

    2014-01-01

    Full Text Available Split cord malformations (SCMs are thought to be rare abnormalities representing 3.8-5% of all spinal cord anomalies. The prevalence is estimated to be 1 in 5499 live births (0.02%, with a slight female predominance (1.3:1. Although the estimates of prevalence vary, Type I SCM occurs more frequently than Type II SCM. In this paper, we are reporting the clinical presentation and imaging findings of multi-level SCM in a 27-year-old male. A literature review of the embryological background of SCM and pathological hypothesis for this entity is provided. A systematic review has been conducted to identify multi-level SCM cases reported in the literature, followed by proposing a new classification system to further our understanding and management of SCMs.

  19. Multi-level Split Cord Malformation: Do We Need a New Classification?

    Science.gov (United States)

    Alzhrani, Gmaan A; Al-Jehani, Hosam M; Melançon, Denis

    2014-01-01

    Split cord malformations (SCMs) are thought to be rare abnormalities representing 3.8-5% of all spinal cord anomalies. The prevalence is estimated to be 1 in 5499 live births (0.02%), with a slight female predominance (1.3:1). Although the estimates of prevalence vary, Type I SCM occurs more frequently than Type II SCM. In this paper, we are reporting the clinical presentation and imaging findings of multi-level SCM in a 27-year-old male. A literature review of the embryological background of SCM and pathological hypothesis for this entity is provided. A systematic review has been conducted to identify multi-level SCM cases reported in the literature, followed by proposing a new classification system to further our understanding and management of SCMs.

  20. Level sequence and splitting identification of closely-spaced energy levels by angle-resolved analysis of the fluorescence light

    CERN Document Server

    Wu, Z W; Surzhykov, A; Dong, C Z; Fritzsche, S

    2016-01-01

    The angular distribution and linear polarization of the fluorescence light following the resonant photoexcitation is investigated within the framework of the density matrix and second-order perturbation theory. Emphasis has been placed on "signatures" for determining the level sequence and splitting of intermediate (partially) overlapping resonances, if analyzed as a function of the photon energy of the incident light. Detailed computations within the multiconfiguration Dirac-Fock method have been performed especially for the $1s^{2}2s^{2}2p^{6}3s\\;\\, J_{i}=1/2 \\,+\\, \\gamma_{1} \\:\\rightarrow\\: (1s^{2}2s2p^{6}3s)_{1}3p_{3/2}\\;\\, J=1/2, \\, 3/2 \\:\\rightarrow\\: 1s^{2}2s^{2}2p^{6}3s\\;\\, J_{f}=1/2 \\,+\\, \\gamma_{2}$ photoexcitation and subsequent fluorescence emission of atomic sodium. A remarkably strong dependence of the angular distribution and linear polarization of the $\\gamma_{2}$ fluorescence emission is found upon the level sequence and splitting of the intermediate $(1s^{2}2s2p^{6}3s)_{1}3p_{3/2}\\;\\, J=1/2,...

  1. Long-range interactions of hydrogen atoms in excited states. II. Hyperfine-resolved (2 S -2 S ) systems

    Science.gov (United States)

    Jentschura, U. D.; Debierre, V.; Adhikari, C. M.; Matveev, A.; Kolachevsky, N.

    2017-02-01

    The interaction of two excited hydrogen atoms in metastable states constitutes a theoretically interesting problem because of the quasidegenerate 2 P1 /2 levels that are removed from the 2 S states only by the Lamb shift. The total Hamiltonian of the system is composed of the van der Waals Hamiltonian, the Lamb shift, and the hyperfine effects. The van der Waals shift becomes commensurate with the 2 S -2 P3 /2 fine-structure splitting only for close approach (R Hamiltonian matrix a priori is of dimension 64. A careful analysis of the symmetries of the the problem allows one to reduce the dimensionality of the most involved irreducible submatrix to 12. We determine the Hamiltonian matrices and the leading-order van der Waals shifts for states that are degenerate under the action of the unperturbed Hamiltonian (Lamb shift plus hyperfine structure). The leading first- and second-order van der Waals shifts lead to interaction energies proportional to 1 /R3 and 1 /R6 and are evaluated within the hyperfine manifolds. When both atoms are metastable 2 S states, we find an interaction energy of order Ehχ (a0/R ) 6 , where Eh and L are the Hartree and Lamb shift energies, respectively, and χ =Eh/L ≈6.22 ×106 is their ratio.

  2. Collective magnetic splitting in single-photon superradiance

    CERN Document Server

    Kong, Xiangjin

    2016-01-01

    In an ensemble of identical atoms, cooperative effects like sub- or superradiance may alter the decay rates and the energy of specific transitions may be shifted from the single-atom value by the so-called collective Lamb shift. So far, one has considered these effects in ensembles of two-level systems only. In this work we show that in a system with atoms or nuclei under the action of an external magnetic field, an additional, so far unaccounted for collective contribution to the level shifts appears that can amount to seizable deviations from the single-atom Zeeman or magnetic hyperfine splitting. We develop a formalism to describe single-photon superradiance in multi-level systems and quantify the parameter regime for which the collective Lamb shift leads to measurable deviations in the magnetic-field-induced splitting. In particular, we show that this effect should be observable in the nuclear magnetic hyperfine splitting in M\\"ossbauer nuclei embedded in thin-film x-ray cavities.

  3. Breakdown of Atomic Hyperfine Coupling in a Deep Optical-Dipole Trap

    CERN Document Server

    Neuzner, Andreas; Dürr, Stephan; Rempe, Gerhard; Ritter, Stephan

    2015-01-01

    We experimentally study the breakdown of hyperfine coupling for an atom in a deep optical-dipole trap. One-color laser spectroscopy is performed at the resonance lines of a single $^{87}$Rb atom for a trap wavelength of 1064 nm. Evidence of hyperfine breakdown comes from three observations, namely a nonlinear dependence of the transition frequencies on the trap intensity, a splitting of lines which are degenerate for small intensities, and the ability to drive transitions which would be forbidden by selection rules in the absence of hyperfine breakdown. From the data, we infer the hyperfine interval of the $5P_{1/2}$ state and the scalar and tensor polarizabilities for the $5P_{3/2}$ state.

  4. Chlorine Nuclear Quadrupole Hyperfine Structure in the Vinyl - Chloride Complex

    Science.gov (United States)

    Leung, Helen O.; Marshall, Mark D.; Messinger, Joseph P.

    2015-06-01

    The microwave spectrum of the vinyl chloride--hydrogen chloride complex, presented at last year's symposium, is greatly complicated by the presence of two chlorine nuclei as well as an observed, but not fully explained tunneling motion. Indeed, although it was possible at that time to demonstrate conclusively that the complex is nonplanar, the chlorine nuclear quadrupole hyperfine splitting in the rotational spectrum resisted analysis. With higher resolution, Balle-Flygare Fourier transform microwave spectra, the hyperfine structure has been more fully resolved, but appears to be perturbed for some rotational transitions. It appears that knowledge of the quadrupole coupling constants will provide essential information regarding the structure of the complex, specifically the location of the hydrogen atom in HCl. Our progress towards obtaining values for these constants will be presented.

  5. Landau Level Splittings, Phase Transitions, and Nonuniform Charge Distribution in Trilayer Graphene

    Science.gov (United States)

    Campos, Leonardo C.; Taychatanapat, Thiti; Serbyn, Maksym; Surakitbovorn, Kawin; Watanabe, Kenji; Taniguchi, Takashi; Abanin, Dmitry A.; Jarillo-Herrero, Pablo

    2016-08-01

    We report on magnetotransport studies of dual-gated, Bernal-stacked trilayer graphene (TLG) encapsulated in boron nitride crystals. We observe a quantum Hall effect staircase which indicates a complete lifting of the 12-fold degeneracy of the zeroth Landau level. As a function of perpendicular electric field, our data exhibit a sequence of phase transitions between all integer quantum Hall states in the filling factor interval -8 theoretical model and argue that, in contrast to monolayer and bilayer graphene, the observed Landau level splittings and quantum Hall phase transitions can be understood within a single-particle picture, but imply the presence of a charge density imbalance between the inner and outer layers of TLG, even at charge neutrality and zero transverse electric field. Our results indicate the importance of a previously unaccounted band structure parameter which, together with a more accurate estimate of the other tight-binding parameters, results in a significantly improved determination of the electronic and Landau level structure of TLG.

  6. Relativistic coupled cluster calculations on hyperfine structures and electromagnetic transition amplitudes of In III

    CERN Document Server

    Roy, Sourav; Majumder, Sonjoy

    2014-01-01

    Hyperfine constants and anomalies of ground as well as few low lying excited states of $^{113,115,117}$In III are studied with highly correlated relativistic coupled-cluster theory. The ground state hyperfine splitting of $^{115}$In III is estimated to be 106.8 GHz. A shift of almost 1.9 GHz of the above frequency has been calculated due to modified nuclear dipole moment. This splitting result shows its applicability as communication band and frequency standards at $10^{-11}$ sec. Correlations study of hyperfine constants indicates a few distinct features of many-body effects in the wave-functions in and near the nuclear region of this ion. Astrophysically important forbidden transition amplitudes are estimated for the first time in the literature to our knowledge. The calculated oscillator strengths of few allowed transitions are compared with recent experimental and theoretical results wherever available.

  7. Nuclear radiative recoil corrections to the hyperfine structure of S-states in muonic hydrogen

    Science.gov (United States)

    Faustov, R. N.; Martynenko, A. P.; Martynenko, F. A.; Sorokin, V. V.

    2017-09-01

    Nuclear radiative recoil corrections of order α( Zα)5 to the hyperfine splitting of S-states in muonic hydrogen are calculated on the basis of quasipotential method in quantum electrodynamics. The calculation is performed in the infrared safe Fried-Yennie gauge. Modern experimental data on the proton form factors are used.

  8. Spectroscopy Apparatus for the Measurement of The Hyperfine Structure of Antihydrogen

    CERN Document Server

    Malbrunot, C; Diermaier, M; Dilaver, N; Friedreich, S; Kolbinger, B; Lehner, S; Lundmark, R; Massiczek, O; Radics, B; Sauerzopf, C; Simon, M; Widmann, E; Wolf, M; Wunschek, B; Zmeskal, J

    2014-01-01

    The ASACUSA CUSP collaboration at the Antiproton Decelerator (AD) of CERN is planning to measure the ground-state hyperfine splitting of antihydrogen using an atomic spectroscopy beamline. We describe here the latest developments on the spectroscopy apparatus developed to be coupled to the antihydrogen production setup (CUSP).

  9. Structural Equation Modeling Applied to the Reaction to Stock Dividends and Stock Splits: integrating signaling, liquidity and optimal price level

    Directory of Open Access Journals (Sweden)

    Kelmara Mendes Vieira

    2011-03-01

    Full Text Available This work develops a hybrid model of structural equations able to take simultaneously the hypotheses of signaling, liquidity, and optimal price level to explain the reaction to the stock dividends and stock splits. In the measurement model four constructs were defined: trading activity, spread, size, and price. The structural model defines extant relations from the proposition of 22 sub-hypotheses. A sample of 321 splits performed in the Brazilian market between 1990 and 2004 was used for assessing the model. Confirmatory factor analysis revealed the validity and coherence of the four constructs. The structural model confirmed 9 original sub-hypotheses.

  10. Polarized Spatial Splitting of Four-Wave Mixing Signal in Multi-Level Atomic Systems

    Institute of Scientific and Technical Information of China (English)

    FU Yu-Xin; ZHAO Jin-Yan; SONG Yue; DAI Guo-Xian; HUO Shu-Li; ZHANG Yan-Peng

    2011-01-01

    @@ We illustrate our experimental observation of the periodic changes of spatial splitting of the generated four-wave mixing(FWM)signal induced by different polarization states of one of the dressing beams.It is pointed out that the changes of intensity of the dressing beam and the FWM signal have influences on the spatial splitting and their influences compete with each other.The differences between p- and s-polarized FWM beams are demonstrated.The influences of the dressing beams, which lead to the larger spatial splitting with different polarization states or frequency detuning, are observed as well.%We illustrate our experimental observation of the periodic changes of spatial splitting of the generated four-wave mixing (FWM) signal induced by different polarization states of one of the dressing beams. It is pointed out that the changes of intensity of the dressing beam and the FWM signal have influences on the spatial splitting and their influences compete with each other. The differences between p- and s-polarized FWM beams are demonstrated.The influences of the dressing beams, which lead to the larger spatial splitting with different polarization states or frequency detuning, are observed as well.

  11. Hyperfine Structure Measurements of Antiprotonic $^3$He using Microwave Spectroscopy

    CERN Document Server

    Friedreich, Susanne

    The goal of this project was to measure the hyperfine structure of $\\overline{\\text{p}}^3$He$^+$ using the technique of laser-microwave-laser spectroscopy. Antiprotonic helium ($\\overline{\\text{p}}$He$^+$) is a neutral exotic atom, consisting of a helium nucleus, an electron and an antiproton. The interactions of the angular momenta of its constituents cause a hyperfine splitting ({HFS}) within the energy states of this new atom. The 3\\% of formed antiprotonic helium atoms which remain in a metastable, radiative decay-dominated state have a lifetime of about 1-3~$\\mu$s. This time window is used to do spectroscopic studies. The hyperfine structure of $\\overline{\\text{p}}^4$He$^+$ was already extensively investigated before. From these measurements the spin magnetic moment of the antiproton can be determined. A comparison of the result to the proton magnetic moment provides a test of {CPT} invariance. Due to its higher complexity the new exotic three-body system of $\\overline{\\text{p}}^3$He$^+$ is a cross-check...

  12. Splitting of the zero-energy Landau level and universal dissipative conductivity at critical points in disordered graphene.

    Science.gov (United States)

    Ortmann, Frank; Roche, Stephan

    2013-02-22

    We report on robust features of the longitudinal conductivity (σ(xx)) of the graphene zero-energy Landau level in the presence of disorder and varying magnetic fields. By mixing an Anderson disorder potential with a low density of sublattice impurities, the transition from metallic to insulating states is theoretically explored as a function of Landau-level splitting, using highly efficient real-space methods to compute the Kubo conductivities (both σ(xx) and Hall σ(xy)). As long as valley degeneracy is maintained, the obtained critical conductivity σ(xx) =/~ 1.4e(2)/h is robust upon an increase in disorder (by almost 1 order of magnitude) and magnetic fields ranging from about 2 to 200 T. When the sublattice symmetry is broken, σ(xx) eventually vanishes at the Dirac point owing to localization effects, whereas the critical conductivities of pseudospin-split states (dictating the width of a σ(xy) = 0 plateau) change to σ(xx) =/~ e(2)/h, regardless of the splitting strength, superimposed disorder, or magnetic strength. These findings point towards the nondissipative nature of the quantum Hall effect in disordered graphene in the presence of Landau level splitting.

  13. Observation of Hyperfine Transitions in Trapped Ground-State Antihydrogen

    CERN Document Server

    Olin, Arthur

    2015-01-01

    This paper discusses the first observation of stimulated magnetic resonance transitions between the hyperfine levels of trapped ground state atomic antihydrogen, confirming its presence in the ALPHA apparatus. Our observations show that these transitions are consistent with the values in hydrogen to within 4~parts~in~$10^3$. Simulations of the trapped antiatoms in a microwave field are consistent with our measurements.

  14. Hyperfine magnetic fields in substituted Finemet alloys

    Energy Technology Data Exchange (ETDEWEB)

    Brzózka, K., E-mail: k.brzozka@uthrad.pl [University of Technology and Humanities in Radom, Department of Physics (Poland); Sovák, P. [P.J. Šafárik University, Institute of Physics (Slovakia); Szumiata, T.; Gawroński, M.; Górka, B. [University of Technology and Humanities in Radom, Department of Physics (Poland)

    2016-12-15

    Transmission Mössbauer spectroscopy was used to determine the hyperfine fields of Finemet-type alloys in form of ribbons, substituted alternatively by Mn, Ni, Co, Al, Zn, V or Ge of various concentration. The comparative analysis of magnetic hyperfine fields was carried out which enabled to understand the role of added elements in as-quenched as well as annealed samples. Moreover, the influence of the substitution on the mean direction of the local hyperfine magnetic field was examined.

  15. Magnetoinfrared Spectroscopy of Landau Levels and Zeeman Splitting of Three-Dimensional Massless Dirac Fermions in ZrTe(5).

    Science.gov (United States)

    Chen, R Y; Chen, Z G; Song, X-Y; Schneeloch, J A; Gu, G D; Wang, F; Wang, N L

    2015-10-23

    We present a magnetoinfrared spectroscopy study on a newly identified three-dimensional (3D) Dirac semimetal ZrTe(5). We observe clear transitions between Landau levels and their further splitting under a magnetic field. Both the sequence of transitions and their field dependence follow quantitatively the relation expected for 3D massless Dirac fermions. The measurement also reveals an exceptionally low magnetic field needed to drive the compound into its quantum limit, demonstrating that ZrTe(5) is an extremely clean system and ideal platform for studying 3D Dirac fermions. The splitting of the Landau levels provides direct, bulk spectroscopic evidence that a relatively weak magnetic field can produce a sizable Zeeman effect on the 3D Dirac fermions, which lifts the spin degeneracy of Landau levels. Our analysis indicates that the compound evolves from a Dirac semimetal into a topological line-node semimetal under the current magnetic field configuration.

  16. High-precision QED calculations of the hyperfine structure in hydrogen and transition rates in multicharged ions

    Energy Technology Data Exchange (ETDEWEB)

    Volotka, A.V.

    2006-07-01

    Studies of the hyperfine splitting in hydrogen are strongly motivated by the level of accuracy achieved in recent atomic physics experiments, which yield finally model-independent informations about nuclear structure parameters with utmost precision. Considering the current status of the determination of corrections to the hyperfine splitting of the ground state in hydrogen, this thesis provides further improved calculations by taking into account the most recent value for the proton charge radius. Comparing theoretical and experimental data of the hyperfine splitting in hydrogen the proton-size contribution is extracted and a relativistic formula for this contribution is derived in terms of moments of the nuclear charge and magnetization distributions. An iterative scheme for the determination of the Zemach and magnetic radii of the proton is proposed. As a result, the Zemach and magnetic radii are determined and the values are compared with the corresponding ones deduced from data obtained in electron-proton scattering experiments. The extraction of the Zemach radius from a rescaled difference between the hyperfine splitting in hydrogen and in muonium is considered as well. Investigations of forbidden radiative transitions in few-electron ions within ab initio QED provide a most sensitive tool for probing the influence of relativistic electron-correlation and QED corrections to the transition rates. Accordingly, a major part of this thesis is devoted to detailed studies of radiative and interelectronic-interaction effects to the transition probabilities. The renormalized expressions for the corresponding corrections in one- and twoelectron ions as well as for ions with one electron over closed shells are derived employing the two-time Green's function method. Numerical results for the correlation corrections to magnetic transition rates in He-like ions are presented. For the first time also the frequency-dependent contribution is calculated, which has to be

  17. Estimation of Missing Observations in Two-Level Split-Plot Designs

    DEFF Research Database (Denmark)

    Almimi, Ashraf A.; Kulahci, Murat; Montgomery, Douglas C.

    2008-01-01

    Inserting estimates for the missing observations from split-plot designs restores their balanced or orthogonal structure and alleviates the difficulties in the statistical analysis. In this article, we extend a method due to Draper and Stoneman to estimate the missing observations from unreplicat...

  18. Photovoltaic reciprocity and quasi-Fermi level splitting in nanostructure-based solar cells (Conference Presentation)

    Science.gov (United States)

    Aeberhard, Urs

    2017-04-01

    The photovoltaic reciprocity theory relates the electroluminescence spectrum of a solar cell under applied bias to the external photovoltaic quantum efficiency of the device as measured at short circuit conditions [1]. So far, the theory has been verified for a wide range of devices and material systems and forms the basis of a growing number of luminesecence imaging techniques used in the characterization of photovoltaic materials, cells and modules [2-5]. However, there are also some examples where the theory fails, such as in the case of amorphous silicon. In our contribution, we critically assess the assumptions made in the derivation of the theory and compare its predictions with rigorous formal relations as well as numerical computations in the framework of a comprehensive quantum-kinetic theory of photovoltaics [6] as applied to ultra-thin absorber architectures [7]. One of the main applications of the photovoltaic reciprocity relation is the determination of quasi-Fermi level splittings (QFLS) in solar cells from the measurement of luminescence. In nanostructure-based photovoltaic architectures, the determination of QFLS is challenging, but instrumental to assess the performance potential of the concepts. Here, we use our quasi-Fermi level-free theory to investigate existence and size of QFLS in quantum well and quantum dot solar cells. [1] Uwe Rau. Reciprocity relation between photovoltaic quantum efficiency and electrolumines- cent emission of solar cells. Phys. Rev. B, 76(8):085303, 2007. [2] Thomas Kirchartz and Uwe Rau. Electroluminescence analysis of high efficiency cu(in,ga)se2 solar cells. J. Appl. Phys., 102(10), 2007. [3] Thomas Kirchartz, Uwe Rau, Martin Hermle, Andreas W. Bett, Anke Helbig, and Jrgen H. Werner. Internal voltages in GaInP-GaInAs-Ge multijunction solar cells determined by electro- luminescence measurements. Appl. Phys. Lett., 92(12), 2008. [4] Thomas Kirchartz, Anke Helbig, Wilfried Reetz, Michael Reuter, Jürgen H. Werner, and

  19. Three level spinal dysraphism: multiple composite Type 1 and Type 2 split cord malformatıon

    Directory of Open Access Journals (Sweden)

    Alatas I.

    2014-12-01

    Full Text Available It has reported an uncommon case a 3 year-old girl a composite split cord malformation (SCM with two different levels of SCM type1 and one level SCM type2, tight filum and sacral dermal sinus. The patient was admitted with a hypertrichosis and hyperpigmented patch. MRI of whole spine and brain was done. SCM type1 at T 7 and L2 levels and SCM typ2 at T11 level were removed then tight filum was cut and dermal sinus was excised at different sites during the same surge

  20. Improved theory of the muonium hyperfine structure

    CERN Document Server

    Kinoshita, T

    1994-01-01

    Terms contributing to the hyperfine structure of the muonium ground state at the level of few tenths of keV have been evaluated. The $\\alpha^2 (Z\\alpha)$ radiative correction has been calculated numerically to the precision of 0.02 kHz. Leading $\\ln (Z\\alpha )$ terms of order $\\alpha^{4-n} (Z\\alpha)^n , n=1,2,3,$ and some relativistic corrections have been evaluated analytically. The theoretical uncertainty is now reduced to 0.17 keV. At present, however, it is not possible to test QED to this precision because of the 1.34 kHz uncertainty due to the muon mass.

  1. Resonant transitions between split energy levels triple-barrier nanostructures and their application perspectives in submillimeter-wave devices

    CERN Document Server

    Golant, E I

    2002-01-01

    A mathematical model has been developed for electronic coherent tunneling through the triple-barrier quantum-dimensional semiconductor heterostructures in the terahertz electric field. Using this model the frequency dependences of the negative dynamic conductivity for triple-barrier structures with coherent electron tunneling through the split energy levels are investigated. It has been shown that these structures can be employed in far-infrared coherent quantum lasers, the wave length being 600 mu m (5 THz)

  2. Absolute frequency measurements and hyperfine structures of the molecular iodine transitions at 578 nm

    CERN Document Server

    Kobayashi, Takumi; Hosaka, Kazumoto; Inaba, Hajime; Okubo, Sho; Tanabe, Takehiko; Yasuda, Masami; Onae, Atsushi; Hong, Feng-Lei

    2016-01-01

    We report absolute frequency measurements of 81 hyperfine components of the rovibrational transitions of molecular iodine at 578 nm using the second harmonic generation of an 1156-nm external-cavity diode laser and a fiber-based optical frequency comb. The relative uncertainties of the measured absolute frequencies are typically $1.4\\times10^{-11}$. Accurate hyperfine constants of four rovibrational transitions are obtained by fitting the measured hyperfine splittings to a four-term effective Hamiltonian including the electric quadrupole, spin-rotation, tensor spin-spin, and scalar spin-spin interactions. The observed transitions can be good frequency references at 578 nm, and are especially useful for research using atomic ytterbium since the transitions are close to the $^{1}S_{0}-^{3}P_{0}$ clock transition of ytterbium.

  3. Multispectral plasmon-induced transparency in hyperfine terahertz meta-molecules

    Science.gov (United States)

    Yang, Shengyan; Xia, Xiaoxiang; Liu, Zhe; Yiwen, E.; Wang, Yujin; Tang, Chengchun; Li, Wuxia; Li, Junjie; Wang, Li; Gu, Changzhi

    2016-11-01

    We experimentally and theoretically demonstrated an approach to achieve multispectral plasmon-induced transparency (PIT) by utilizing meta-molecules that consist of hyperfine terahertz meta-atoms. The feature size of such hyperfine meta-atoms is 400 nm, which is one order smaller than that of normal terahertz metamaterials. The hyperfine meta-atoms with close eigenfrequencies and narrow resonant responses introduce different metastable energy levels, which makes the multispectral PIT possible. In the triple PIT system, the slow light effect is further confirmed as the effective group delay at three transmission windows can reach 7.3 ps, 7.4 ps and 4.5 ps, respectively. Precisely controllable manipulation of the PIT peaks in such hyperfine meta-molecules was also proven. The new hyperfine planar design is not only suitable for high-integration applications, but also exhibits significant slow light effect, which has great potential in advanced multichannel optical information processing. Moreover, it reveals the possibility to construct hyperfine N-level energy systems by artificial hyperfine plasmonic structures, which brings a significant prospect for applications on miniaturized plasmonic devices.

  4. Positronium energy levels at order $m \\alpha^7$: vacuum polarization corrections in the two-photon-annihilation channel

    CERN Document Server

    Adkins, Gregory S; Salinger, M D; Wang, Ruihan

    2015-01-01

    We have calculated all contributions to the energy levels of parapositronium at order $m \\alpha^7$ coming from vacuum polarization corrections to processes involving virtual annihilation to two photons. This work is motivated by ongoing efforts to improve the experimental determination of the positronium ground-state hyperfine splitting.

  5. Positronium energy levels at order mα7: Vacuum polarization corrections in the two-photon-annihilation channel

    Directory of Open Access Journals (Sweden)

    Gregory S. Adkins

    2015-07-01

    Full Text Available We have calculated all contributions to the energy levels of parapositronium at order mα7 coming from vacuum polarization corrections to processes involving virtual annihilation to two photons. This work is motivated by ongoing efforts to improve the experimental determination of the positronium ground-state hyperfine splitting.

  6. Effects of nonstatistical hyperfine populations in muon capture by polarized nuclei

    CERN Document Server

    Hambro, L

    1975-01-01

    The nonstatistical populations of the hyperfine (HF) levels in muonic atoms brought about by the polarization of the nuclear targets and their influence on the nuclear muon capture probability are considered. The nuclear-capture rates from the upper and lower HF states of the 1s atomic orbit can be markedly different. The usefulness of muon capture by polarized nuclei to probe qualitatively, and possible quantitatively, the difference between the hyperfine capture rates is demonstrated. The best targets to exploit this effect are those for which the hyperfine conversion rate is small in comparison to muon disappearance rate, and which can be polarized maximally to a degree reliably determinable. (18 refs).

  7. Hyperfine interaction versus strong laser field-optical Back-Goudsmit (Paschen-Back) effect

    Science.gov (United States)

    Gawlik, Wojciech

    1991-08-01

    Strong laser perturbation of an atom with fine or hyperfine structure is analyzed in the context of a level-crossing experiment. The effect of sufficiently powerful, detuned, and/or spectrally broad light is to produce ``hyperfine uncoupling,'' which can be regarded as the optical Back-Goudsmit effect. It is easily understood in terms of an analogy between the level-crossing effect and double-slit experiment.

  8. Development of a multi-level approach to model and optimise the Kalina Split Cycle

    DEFF Research Database (Denmark)

    Larsen, Ulrik; Nguyen, Tuong-Van; Haglind, Fredrik

    2012-01-01

    efficiencies than conventional power cycles and could be suitable for this purpose. The Split Cycle technique provides a method to further increase the thermal efficiency, by reducing the thermodynamic losses in the heat recovery system. This is achieved by having two separate streams of different ammonia...... cycle. Results suggest a 9% net power output increase and 7% higher thermal efficiency compared to the baseline case.......In the marine sector there is a strong motivation for increasing the propulsion system energy efficiency, mainly because of increasing fuel prices and stricter upcoming emission regulations. The Kalina cycle, based on a mixture of ammonia and water as working fluid, exhibits higher conversion...

  9. Effect of Ti{sup 4+} substitution on the hyperfine properties of Li-Sb-Ti ferrites using Moessbauer spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Chongtham, Shivaji, E-mail: schongtham@rediffmail.com [Manipur Science and Technology Council, R and D Division (India); Soibam, Ibetombi; Phanjoubam, Sumitra; Sarma, H. N. K. [Manipur University, Department of Physics (India); Verma, H. C. [IIT Kanpur, Department of Physics (India)

    2008-11-15

    Moessbauer investigations were carried out at room temperature on the ferrite system Li{sub 0.6+0.5t}Fe{sub 2.3-1.5t}Ti{sub t}Sb{sub 0.1}O{sub 4} (0.0 {<=} t {<=} 1.0 in steps of 0.2). The effect of Ti{sup 4+} concentration on the various hyperfine interactions like Isomer shift, quadrupole splitting and internal magnetic field have been studied. The spectra exhibited well-defined Zeeman sextets at low substitution level, corresponding to the A and B sites. The sample with t = 1.0 showed paramagnetic behaviour. The results obtained have been discussed.

  10. Polarized scattering with Paschen-Back effect, hyperfine structure, and partial frequency redistribution in magnetized stellar atmospheres

    CERN Document Server

    Sowmya, K; Stenflo, J O; Sampoorna, M

    2015-01-01

    $F$-state interference significantly modifies the polarization produced by scattering processes in the solar atmosphere. Its signature in the emergent Stokes spectrum in the absence of magnetic fields is depolarization in the line core. In the present paper, we derive the partial frequency redistribution (PRD) matrix that includes interference between the upper hyperfine structure states of a two-level atom in the presence of magnetic fields of arbitrary strengths. The theory is applied to the Na I D$_2$ line that is produced by the transition between the lower $J=1/2$ and upper $J=3/2$ states which split into $F$ states because of the coupling with the nuclear spin $I_s=3/2$. The properties of the PRD matrix for the single-scattering case is explored, in particular, the effects of the magnetic field in the Paschen--Back regime and their usefulness as a tool for the diagnostics of solar magnetic fields.

  11. Polarized Scattering with Paschen-Back Effect, Hyperfine Structure, and Partial Frequency Redistribution in Magnetized Stellar Atmospheres

    Science.gov (United States)

    Sowmya, K.; Nagendra, K. N.; Stenflo, J. O.; Sampoorna, M.

    2014-05-01

    F-state interference significantly modifies the polarization produced by scattering processes in the solar atmosphere. Its signature in the emergent Stokes spectrum in the absence of magnetic fields is depolarization in the line core. In the present paper, we derive the partial frequency redistribution (PRD) matrix that includes interference between the upper hyperfine structure states of a two-level atom in the presence of magnetic fields of arbitrary strengths. The theory is applied to the Na I D2 line that is produced by the transition between the lower J = 1/2 and upper J = 3/2 states which split into F states because of the coupling with the nuclear spin Is = 3/2. The properties of the PRD matrix for the single-scattering case is explored, in particular, the effects of the magnetic field in the Paschen-Back regime and their usefulness as a tool for the diagnostics of solar magnetic fields.

  12. Hyperfine Structure in Rotational Spectra of Deuterated Molecules: the Hds and ND_3 Case Studies

    Science.gov (United States)

    Cazzoli, Gabriele; Puzzarini, Cristina

    2016-06-01

    The determination of hyperfine parameters (quadrupole-coupling, spin-spin coupling, and spin-rotation constants) is one of the aims of high-resolution rotational spectroscopy. These parameters are relevant not only from a spectroscopic point of view, but also from a physical and/or chemical viewpoint, as they might provide detailed information on the chemical bond, structure, etc. In addition, the hyperfine structure of rotational spectra is so characteristic that its analysis may help in assigning the spectra of unknown species. In astronomical observations, hyperfine structures of rotational spectra would allow us to gain information on column densities and kinematics, and the omission of taking them into account can lead to a misinterpretation of the line width of the molecular emission lines. Nevertheless, the experimental determination of hyperfine constants can be a challenge not only for actual problems in resolving hyperfine structures themselves, but also due to the lack of reliable estimates or the complexity of the hyperfine structure itself. It is thus important to be able to rely on good predictions for such parameters, which can nowadays be provided by quantum-chemical calculations. In fact, the fruitful interplay of experiment and theory will be demonstrated by means of two study cases: the hypefine structure of the rotational spectra of HDS and ND_3. From an experimental point of view, the Lamb-dip technique has been employed to improve the resolving power in themillimeter- and submillimeterwave frequency range by at least one order of magnitude, thus making it possible to perform sub-Doppler measurements as well as to resolve narrow hyperfine structures. Concerning theory, it will be demonstrated that high-level calculations can provide quantitative estimates for hyperfine parameters (quadrupole coupling constants, spin-rotation tensors, spin-spin couplings, etc.) and shown how theoretical predictions are often essential for a detailed analysis of

  13. Embryo splitting

    Directory of Open Access Journals (Sweden)

    Karl Illmensee

    2010-04-01

    Full Text Available Mammalian embryo splitting has successfully been established in farm animals. Embryo splitting is safely and efficiently used for assisted reproduction in several livestock species. In the mouse, efficient embryo splitting as well as single blastomere cloning have been developed in this animal system. In nonhuman primates embryo splitting has resulted in several pregnancies. Human embryo splitting has been reported recently. Microsurgical embryo splitting under Institutional Review Board approval has been carried out to determine its efficiency for blastocyst development. Embryo splitting at the 6–8 cell stage provided a much higher developmental efficiency compared to splitting at the 2–5 cell stage. Embryo splitting may be advantageous for providing additional embryos to be cryopreserved and for patients with low response to hormonal stimulation in assisted reproduction programs. Social and ethical issues concerning embryo splitting are included regarding ethics committee guidelines. Prognostic perspectives are presented for human embryo splitting in reproductive medicine.

  14. Band electron spectrum and thermodynamic properties of the pseudospin-electron model with tunneling splitting of levels

    Directory of Open Access Journals (Sweden)

    O.Ya.Farenyuk

    2006-01-01

    Full Text Available The pseudospin-electron model with tunneling splitting of levels is considered. Generalization of dynamic mean-field method for systems with correlated hopping was applied to the investigation of the model. Electron spectra, electron concentrations, average values of pseudospins and grand canonical potential were calculated within the alloy-analogy approximation. Electron spectrum and dependencies of the electron concentrations on chemical potential were obtained. It was shown that in the alloy-analogy approximation, the model possesses the first order phase transition to ferromagnetic state with the change of chemical potential and the second order phase transition with the change of temperature.

  15. Study of hyperfine structure in simple atoms and precision tests of the bound state QED

    Energy Technology Data Exchange (ETDEWEB)

    Karshenboim, S.G. [Max-Planck-Institut fuer Quantenoptik, 85748 Garching (Germany); D.I. Mendeleev Institute for Metrology (VNIIM), St. Petersburg 190005 (Russian Federation); Eidelman, S.I. [Budker Institute for Nuclear Physics and Novosibirsk State University, Novosibirsk, 630090 (Russian Federation); Fendel, P. [Max-Planck-Institut fuer Quantenoptik, 85748 Garching (Germany); Ivanov, V.G. [Pulkovo Observatory, St. Petersburg 196140 (Russian Federation); Kolachevsky, N.N. [P.N. Lebedev Physics Institute, Moscow, 119991 (Russian Federation); Shelyuto, V.A. [D.I. Mendeleev Institute for Metrology (VNIIM), St. Petersburg 190005 (Russian Federation); Haensch, T.W. [Max-Planck-Institut fuer Quantenoptik, 85748 Garching (Germany)

    2006-12-15

    We consider the most accurate tests of bound state QED, precision theory of simple atoms, related to the hyperfine splitting in light hydrogen-like atoms. We discuss the HFS interval of the 1s state in muonium and positronium and of the 2s state in hydrogen, deuterium and helium-3 ion. We summarize their QED theory and pay attention to involved effects of strong interactions. We also consider recent optical measurements of the 2s HFS interval in hydrogen and deuterium.

  16. Study of hyperfine structure in simple atoms and precision tests of the bound state QED

    CERN Document Server

    Karshenboim, S G; Fendel, P; Ivanov, V G; Kolachevsky, N N; Shelyuto, V A; Hänsch, T W

    2006-01-01

    We consider the most accurate tests of bound state QED, precision theory of simple atoms, related to the hyperfine splitting in light hydrogen-like atoms. We discuss the HFS interval of the 1s state in muonium and positronium and of the 2s state in hydrogen, deuterium and helium-3 ion. We summarize their QED theory and pay attention to involved effects of strong interactions. We also consider recent optical measurements of the 2s HFS interval in hydrogen and deuterium.

  17. Model for the hyperfine structure of electronically-excited ${\\rm KCs}$ molecules

    CERN Document Server

    Orbán, A; Krieglsteiner, O; Nägerl, H -C; Dulieu, O; Crubellier, A; Bouloufa-Maafa, N

    2015-01-01

    A model for determining the hyperfine structure of the excited electronic states of diatomic bialkali heteronuclear molecules is formulated from the atomic hyperfine interactions, and is applied to the case of bosonic $^{39}$KCs and fermionic $^{40}$KCs molecules. The hyperfine structure of the potential energy curves of the states correlated to the K($4s\\,^2S_{1/2}$)+Cs($6p\\,^2P_{1/2,3/2}$) dissociation limits is described in terms of different coupling schemes depending on the internuclear distance $R$. These results provide the first step in the calculation of the hyperfine structure of rovibrational levels of these excited molecular states in the perspective of the identification of efficient paths for creating ultracold ground-state KCs molecules.

  18. Dephasing and hyperfine interaction in carbon nanotubes double quantum dots

    DEFF Research Database (Denmark)

    Reynoso, Andres Alejandro; Flensberg, Karsten

    2012-01-01

    We study theoretically the return probability experiment, which is used to measure the dephasing time T-2*, in a double quantum dot (DQD) in semiconducting carbon nanotubes with spin-orbit coupling and disorder-induced valley mixing. Dephasing is due to hyperfine interaction with the spins of the C......-13 nuclei. Due to the valley and spin degrees of freedom, four bounded states exist for any given longitudinal mode in the quantum dot. At zero magnetic field, the spin-orbit coupling and the valley mixing split those four states into two Kramers doublets. The valley-mixing term for a given dot...... is determined by the intradot disorder; this leads to (i) states in the Kramers doublets belonging to different dots being different, and (ii) nonzero interdot tunneling amplitudes between states belonging to different doublets. We show that these amplitudes give rise to new avoided crossings, as a function...

  19. Tuning the surface Fermi level on p-type gallium nitride nanowires for efficient overall water splitting.

    Science.gov (United States)

    Kibria, M G; Zhao, S; Chowdhury, F A; Wang, Q; Nguyen, H P T; Trudeau, M L; Guo, H; Mi, Z

    2014-04-30

    Solar water splitting is one of the key steps in artificial photosynthesis for future carbon-neutral, storable and sustainable source of energy. Here we show that one of the major obstacles for achieving efficient and stable overall water splitting over the emerging nanostructured photocatalyst is directly related to the uncontrolled surface charge properties. By tuning the Fermi level on the nonpolar surfaces of gallium nitride nanowire arrays, we demonstrate that the quantum efficiency can be enhanced by more than two orders of magnitude. The internal quantum efficiency and activity on p-type gallium nitride nanowires can reach ~51% and ~4.0 mol hydrogen h(-1) g(-1), respectively. The nanowires remain virtually unchanged after over 50,000 μmol gas (hydrogen and oxygen) is produced, which is more than 10,000 times the amount of photocatalyst itself (~4.6 μmol). The essential role of Fermi-level tuning in balancing redox reactions and in enhancing the efficiency and stability is also elucidated.

  20. Prospects of In-Flight Hyperfine Spectroscopy of (Anti)Hydrogen for Tests of CPT Symmetry

    CERN Document Server

    Widmann, Eberhard

    2016-01-01

    The ground-state hyperfine splitting of antihydrogen promises one of the most sensitive tests of CPT symmetry. The ASACUSA collaboration is pursuing a measurement of this splitting in a Rabi-type experiment using a polarized beam from a CUSP magnet at the Antiproton Decelerator of CERN. With the initial intention of characterizing the Rabi apparatus, a polarized source of cold hydrogen was built and the $\\sigma_1$ transition of hydrogen was measured to a few ppb precision. A measurement of the $\\pi_1$ transition is being prepared. The availability of this beam opens the possibility to perform first measurements of some coefficients within the nonminimal Standard-Model Extension.

  1. Alignment, vibronic level splitting, and coherent coupling effects on the pump-probe polarization anisotropy.

    Science.gov (United States)

    Smith, Eric R; Jonas, David M

    2011-04-28

    The pump-probe polarization anisotropy is computed for molecules with a nondegenerate ground state, two degenerate or nearly degenerate excited states with perpendicular transition dipoles, and no resonant excited-state absorption. Including finite pulse effects, the initial polarization anisotropy at zero pump-probe delay is predicted to be r(0) = 3/10 with coherent excitation. During pulse overlap, it is shown that the four-wave mixing classification of signal pathways as ground or excited state is not useful for pump-probe signals. Therefore, a reclassification useful for pump-probe experiments is proposed, and the coherent anisotropy is discussed in terms of a more general transition dipole and molecular axis alignment instead of experiment-dependent ground- versus excited-state pathways. Although coherent excitation enhances alignment of the transition dipole, the molecular axes are less aligned than for a single dipole transition, lowering the initial anisotropy. As the splitting between excited states increases beyond the laser bandwidth and absorption line width, the initial anisotropy increases from 3/10 to 4/10. Asymmetric vibrational coordinates that lift the degeneracy control the electronic energy gap and off-diagonal coupling between electronic states. These vibrations dephase coherence and equilibrate the populations of the (nearly) degenerate states, causing the anisotropy to decay (possibly with oscillations) to 1/10. Small amounts of asymmetric inhomogeneity (2 cm(-1)) cause rapid (130 fs) suppression of both vibrational and electronic anisotropy beats on the excited state, but not vibrational beats on the ground electronic state. Recent measurements of conical intersection dynamics in a silicon napthalocyanine revealed anisotropic quantum beats that had to be assigned to asymmetric vibrations on the ground electronic state only [Farrow, D. A.; J. Chem. Phys. 2008, 128, 144510]. Small environmental asymmetries likely explain the observed absence

  2. On the hyperfine structure of the triplet $n^{3}S-$states of the four-electron atoms and ions

    CERN Document Server

    Frolov, Alexei M

    2016-01-01

    Hyperfine structures of the triplet $n^3S-$states in the four-electron Be-atom(s) and Be-like ions are considered. It is shown that to determine the hyperfine structure splitting in such atomic systems one needs to know the triplet electron density at the central atomic nucleus $\\rho_T(0)$. We have developed the procedure which allows allows one to determine the triplet electron density $\\rho_T(0)$ for arbitrary four-electron atoms and ions.

  3. Hyperfine structure of the hydroxyl free radical (OH) in electric and magnetic fields

    Science.gov (United States)

    Maeda, Kenji; Wall, Michael L.; Carr, Lincoln D.

    2015-05-01

    We investigate single-particle energy spectra of the hydroxyl free radical (OH) in the lowest electronic and rovibrational level under combined static electric and magnetic fields, as an example of heteronuclear polar diatomic molecules. In addition to the fine-structure interactions, the hyperfine interactions and centrifugal distortion effects are taken into account to yield the zero-field spectrum of the lowest 2Π3 / 2 manifold to an accuracy of less than 2kHz. We also examine level crossings and repulsions in the hyperfine structure induced by applied electric and magnetic fields. Compared to previous work, we found more than 10 percent reduction of the magnetic fields at level repulsions in the Zeeman spectrum subjected to a perpendicular electric field. In addition, we find new level repulsions, which we call Stark-induced hyperfine level repulsions, that require both an electric field and hyperfine structure. It is important to take into account hyperfine structure when we investigate physics of OH molecules at micro-Kelvin temperatures and below. This research was supported in part by AFOSR Grant No.FA9550-11-1-0224 and by the NSF under Grants PHY-1207881 and NSF PHY-1125915. We appreciate the Aspen Center for Physics, supported in part by the NSF Grant No.1066293, for hospitality.

  4. Spin relaxation in nanowires by hyperfine coupling

    Energy Technology Data Exchange (ETDEWEB)

    Echeverria-Arrondo, C. [Department of Physical Chemistry, Universidad del Pais Vasco UPV/EHU, 48080 Bilbao (Spain); Sherman, E.Ya. [Department of Physical Chemistry, Universidad del Pais Vasco UPV/EHU, 48080 Bilbao (Spain); IKERBASQUE Basque Foundation for Science, 48011 Bilbao, Bizkaia (Spain)

    2012-08-15

    Hyperfine interactions establish limits on spin dynamics and relaxation rates in ensembles of semiconductor quantum dots. It is the confinement of electrons which determines nonzero hyperfine coupling and leads to the spin relaxation. As a result, in nanowires one would expect the vanishing of this effect due to extended electron states. However, even for relatively clean wires, disorder plays a crucial role and makes electron localization sufficient to cause spin relaxation on the time scale of the order of 10 ns. (copyright 2012 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

  5. Understanding heme proteins with hyperfine spectroscopy

    Science.gov (United States)

    Van Doorslaer, Sabine

    2017-07-01

    Heme proteins are versatile proteins that are involved in a large number of biological processes. Many spectroscopic methods are used to gain insight into the different mechanistic processes governing heme-protein functions. Since many (intermediate) states of heme proteins are paramagnetic, electron paramagnetic resonance (EPR) methods, such as hyperfine spectroscopy, offer unique tools for these investigations. This perspective gives an overview of the use of state-of-the-art hyperfine spectroscopy in heme research, focusing on the advantages, limits and challenges of the different techniques.

  6. The energy level splitting for Unharmonic dc SQUID to be used as phase Q-bit

    DEFF Research Database (Denmark)

    Klenov, Nicolai V.; Kornev, Victor K.; Pedersen, Niels Falsig

    2006-01-01

    Dc-SQUID with Josephson junctions characterized by nonsinusoidal current-phase relation is being considered as a basis for phase qubit. It has been shown that the second and third harmonic components each in the current-phase relation are able to provide double-well potential and the energy level...

  7. Hyperfine structure of singly ionized lanthanum and praseodymium

    Institute of Scientific and Technical Information of China (English)

    马洪良

    2002-01-01

    Hyperfine structure spectra of singly ionized lanthanum and praseodymium have been measured by collinearfast-ion-beam laser spectroscopy. All the spectral lines were resolved and the magnetic dipole and electric quadruplecoupling constants of the metastable levels and excited levels were determined. Our results are in agreement withthe published data within the experimental uncertainty. For praseodymium ions, the accuracy of the magnetic dipolecoupling constants are improved by one order of magnitude compared with other published data, and the electricquadruple coupling constants are reported for the first time.

  8. [Tablet splitting].

    Science.gov (United States)

    Quinzler, R; Haefeli, W E

    2006-06-01

    The splitting of scored tablets provides many advantages. One benefit is to achieve dose flexibility to account for the huge interindividual differences in dose requirements for instance in paediatric and geriatric patients, which are often not covered by the available strengths in the market. Moreover, large-sized tablets can easier be swallowed if broken before swallowing and medication costs can often be reduced by splitting brands with higher strength. But not all tablets, mostly unscored tablets, are suitable for splitting. Splitting of extended release formulations can result in an overdose by uncontrolled release of the active component and degradation of the compound can occur if an enteric coating is destroyed by the splitting process. Whether tablets are suitable for splitting depends on the properties of the active component (e.g. light sensitivity), the galenics, the shape of the tablet, and the shape of the scoreline. Moreover, not all patients are informed, able, or willing to split tablets and the majority of the elderly population is not capable to break tablets. When split tablets are prescribed it is therefore important to view the shape of the tablet, to assess the patients ability and willingness to break tablets, to properly inform the patient about the appropriate way of splitting, and if necessary to suggest (and instruct) the use of a tablet splitting device.

  9. A two-time-level split-explicit ocean circulation model (MASNUM) and its validation

    Institute of Scientific and Technical Information of China (English)

    HAN Lei

    2014-01-01

    A two-time-level, three-dimensional numerical ocean circulation model (named MASNUM) was estab-lished with a two-level, single-step Eulerian forward-backward time-differencing scheme. A mathematical model of large-scale oceanic motions was based on the terrain-following coordinated, Boussinesq, Reyn-olds-averaged primitive equations of ocean dynamics. A simple but very practical Eulerian forward-back-ward method was adopted to replace the most preferred leapfrog scheme as the time-differencing method for both barotropic and baroclinic modes. The forward-backward method is of second-order of accuracy, computationally efficient by requiring only one function evaluation per time step, and free of the compu-tational mode inherent in the three-level schemes. This method is superior to the leapfrog scheme in that the maximum time step of stability is twice as large as that of the leapfrog scheme in staggered meshes thus the computational efficiency could be doubled. A spatial smoothing method was introduced to control the nonlinear instability in the numerical integration. An ideal numerical experiment simulating the propa-gation of the equatorial Rossby soliton was performed to test the amplitude and phase error of this new model. The performance of this circulation model was further verified with a regional (northwest Pacific) and a quasi-global (global ocean simulation with the Arctic Ocean excluded) simulation experiments. These two numerical experiments show fairly good agreement with the observations. The maximum time step of stability in these two experiments were also investigated and compared between this model and that model which adopts the leapfrog scheme.

  10. Atomic-Layer-Confined Doping for Atomic-Level Insights into Visible-Light Water Splitting.

    Science.gov (United States)

    Lei, Fengcai; Zhang, Lei; Sun, Yongfu; Liang, Liang; Liu, Katong; Xu, Jiaqi; Zhang, Qun; Pan, Bicai; Luo, Yi; Xie, Yi

    2015-08-03

    A model of doping confined in atomic layers is proposed for atomic-level insights into the effect of doping on photocatalysis. Co doping confined in three atomic layers of In2S3 was implemented with a lamellar hybrid intermediate strategy. Density functional calculations reveal that the introduction of Co ions brings about several new energy levels and increased density of states at the conduction band minimum, leading to sharply increased visible-light absorption and three times higher carrier concentration. Ultrafast transient absorption spectroscopy reveals that the electron transfer time of about 1.6 ps from the valence band to newly formed localized states is due to Co doping. The 25-fold increase in average recovery lifetime is believed to be responsible for the increased of electron-hole separation. The synthesized Co-doped In2S3 (three atomic layers) yield a photocurrent of 1.17 mA cm(-2) at 1.5 V vs. RHE, nearly 10 and 17 times higher than that of the perfect In2S3 (three atomic layers) and the bulk counterpart, respectively.

  11. Hyperfine interactions, the key to multiquark physics

    Energy Technology Data Exchange (ETDEWEB)

    Likpink, H.J.

    1988-08-08

    Clues in the search for a fundamental description of hadron physics based on QCD may be obtained from a phenomenological constituent quark model in which the color-electric force binds quarks into saturated color-singlet hadrons, and finer details of the spectrum and multiquark physics are dominated by the color-magnetic hyperfine interaction. 47 refs.

  12. Fluctuating hyperfine interactions: an updated computational implementation

    Science.gov (United States)

    Zacate, M. O.; Evenson, W. E.

    2015-04-01

    The stochastic hyperfine interactions modeling library (SHIML) is a set of routines written in the C programming language designed to assist in the analysis of stochastic models of hyperfine interactions. The routines read a text-file description of the model, set up the Blume matrix, upon which the evolution operator of the quantum mechanical system depends, and calculate the eigenvalues and eigenvectors of the Blume matrix, from which theoretical spectra of experimental techniques can be calculated. The original version of SHIML constructs Blume matrices applicable for methods that measure hyperfine interactions with only a single nuclear spin state. In this paper, we report an extension of the library to provide support for methods such as Mössbauer spectroscopy and nuclear resonant scattering of synchrotron radiation, which are sensitive to interactions with two nuclear spin states. Examples will be presented that illustrate the use of this extension of SHIML to generate Mössbauer spectra for polycrystalline samples under a number of fluctuating hyperfine field models.

  13. Fluctuating hyperfine interactions: an updated computational implementation

    Energy Technology Data Exchange (ETDEWEB)

    Zacate, M. O., E-mail: zacatem1@nku.edu [Northern Kentucky University, Department of Physics and Geology (United States); Evenson, W. E. [Utah Valley University, Department of Physics (United States)

    2015-04-15

    The stochastic hyperfine interactions modeling library (SHIML) is a set of routines written in the C programming language designed to assist in the analysis of stochastic models of hyperfine interactions. The routines read a text-file description of the model, set up the Blume matrix, upon which the evolution operator of the quantum mechanical system depends, and calculate the eigenvalues and eigenvectors of the Blume matrix, from which theoretical spectra of experimental techniques can be calculated. The original version of SHIML constructs Blume matrices applicable for methods that measure hyperfine interactions with only a single nuclear spin state. In this paper, we report an extension of the library to provide support for methods such as Mössbauer spectroscopy and nuclear resonant scattering of synchrotron radiation, which are sensitive to interactions with two nuclear spin states. Examples will be presented that illustrate the use of this extension of SHIML to generate Mössbauer spectra for polycrystalline samples under a number of fluctuating hyperfine field models.

  14. Hyperfine structure constants for singly ionized manganese (Mn II) using Fourier transform spectroscopy

    Science.gov (United States)

    Townley-Smith, Keeley; Nave, Gillian; Pickering, Juliet C.; Blackwell-Whitehead, Richard J.

    2016-09-01

    We expand on the comprehensive study of hyperfine structure (HFS) in Mn II conducted by Holt et al. (1999) by verifying hyperfine magnetic dipole constants (A) for 20 levels previously measured by Holt et al. (1999) and deriving A constants for 47 previously unstudied levels. The HFS patterns were measured in archival spectra from Fourier transform (FT) spectrometers at Imperial College London and the National Institute of Standards and Technology. Analysis of the FT spectra was carried out in XGREMLIN. Our A constant for the ground level has a lower uncertainty by a factor of 6 than that of Blackwell-Whitehead et al.

  15. Determination of the hyperfine coupling constant of cesium 7S1/2 state

    CERN Document Server

    Yang, Guang; Yang, Baodong; Wang, Junmin

    2016-01-01

    We report the hyperfine splitting (HFS) measurement of cesium (Cs) 7S1/2 state by optical-optical double-resonance spectroscopy in the 6S1/2-6P3/2-7S1/2 (852 nm + 1470 nm) ladder-type system. The HFS frequency calibration is performed by employing a phase-type waveguide electro-optic modulator together with a stable confocal Fabry-Perot cavity. From the measured HFS between F"= 3 and F"= 4 manifolds of Cs 7S1/2 state [HFS = 2183.273(37) MHz], we have determined the magnetic dipole hyperfine coupling constant [A = 545.818(09) MHz], which is in good agreement with the previous work but much more accurate.

  16. Method of extending hyperfine coherence times in Pr^3+:Y_2SiO_5

    CERN Document Server

    Fraval, E; Longdell, J J

    2003-01-01

    In this letter we present a method for increasing the coherence time of praseodymium hyperfine ground state transitions in Pr^3+:Y_2SiO_5 by the application of a specific external magnetic field. The magnitude and angle of the external field is applied such that the Zeeman splitting of a hyperfine transition is at a critical point in three dimensions, making the first order Zeeman shift vanishingly small for the transition. This reduces the influence of the magnetic interactions between the praseodymium ions and the spins in the host lattice on the transition frequency. Using this method a phase memory time of 82ms was observed, a value two orders of magnitude greater than previously reported. It is shown that the residual dephasing is amenable quantum error correction.

  17. Human F7 sequence is split into three deep clades that are related to FVII plasma levels.

    Science.gov (United States)

    Sabater-Lleal, Maria; Soria, José Manuel; Bertranpetit, Jaume; Almasy, Laura; Blangero, John; Fontcuberta, Jordi; Calafell, Francesc

    2006-02-01

    It is widely accepted that FVII levels are strongly, consistently, and independently related to cardiovascular risk. These levels are influenced by genetic and environmental factors. Among the genetic factors, only a limited number of polymorphisms in the F7 gene have been reported, and they explain only a small proportion of the genetic variability. Recently, we have accomplished the complete dissection of the F7 quantitative trait locus responsible for all of the genetic variability observed in FVII levels. Now, we present the thorough study of the haplotype organization of F7 DNA sequence variation among individuals and the evolutionary processes that produced this variation, by sequencing 15 kb of genomic DNA sequence from the F7 locus in 40 unrelated individual (80 chromosomes) from the genetic analysis of idiopathic thrombophilia (GAIT) project as well as four non-human primate species. Our study revealed 49 polymorphisms, of which 39 SNPs were further considered. Genotyping of these DNA variations in the whole family-based GAIT sample helped resolve linkage phases, and a total of 37 distinct haplotypes were identified.Tajima's D was significantly positive in this sample, suggesting balancing selection. This parameter was a reflection of the phylogenetic structure of F7 haplotype, which was deeply split into three well-supported clades or haplogroups, suggesting that functional differences among F7 variants do not depend on a few single-site variations. Moreover, haplogroup 2 was associated with high FVII levels and haplogroup 3 with low levels. In this study, we have for the first time established a clear relation between genotypic variability structure and phenotypic variability of a particular quantitative trait involved in a complex disease.

  18. THE HYPERFINE STRUCTURE OF THE ROTATIONAL SPECTRUM OF HDO AND ITS EXTENSION TO THE THz REGION: ACCURATE REST FREQUENCIES AND SPECTROSCOPIC PARAMETERS FOR ASTROPHYSICAL OBSERVATIONS

    Energy Technology Data Exchange (ETDEWEB)

    Cazzoli, Gabriele; Lattanzi, Valerio; Puzzarini, Cristina [Dipartimento di Chimica “Giacomo Ciamician”, Università di Bologna, Via Selmi 2, I-40126 Bologna (Italy); Alonso, José Luis [Grupo de Espectroscopía Molecular (GEM), Unidad Asociada CSIC, Edificio Quifima, Laboratorios de Espectroscopia y Bioespectroscopia, Parque Científico UVa, Universidad de Valladolid, E-47005 Valladolid (Spain); Gauss, Jürgen, E-mail: cristina.puzzarini@unibo.it [Institut für Physikalische Chemie, Universität Mainz, D-55099 Mainz (Germany)

    2015-06-10

    The rotational spectrum of the mono-deuterated isotopologue of water, HD{sup 16}O, has been investigated in the millimeter- and submillimeter-wave frequency regions, up to 1.6 THz. The Lamb-dip technique has been exploited to obtain sub-Doppler resolution and to resolve the hyperfine (hf) structure due to the deuterium and hydrogen nuclei, thus enabling the accurate determination of the corresponding hf parameters. Their experimental determination has been supported by high-level quantum-chemical calculations. The Lamb-dip measurements have been supplemented by Doppler-limited measurements (weak high-J and high-frequency transitions) in order to extend the predictive capability of the available spectroscopic constants. The possibility of resolving hf splittings in astronomical spectra has been discussed.

  19. Stretchable Complementary Split Ring Resonator (CSRR-Based Radio Frequency (RF Sensor for Strain Direction and Level Detection

    Directory of Open Access Journals (Sweden)

    Seunghyun Eom

    2016-10-01

    Full Text Available In this paper, we proposed a stretchable radio frequency (RF sensor to detect strain direction and level. The stretchable sensor is composed of two complementary split ring resonators (CSRR with microfluidic channels. In order to achieve stretchability, liquid metal (eutectic gallium-indium, EGaIn and Ecoflex substrate are used. Microfluidic channels are built by Ecoflex elastomer and microfluidic channel frames. A three-dimensional (3D printer is used for fabrication of microfluidic channel frames. Two CSRR resonators are designed to resonate 2.03 GHz and 3.68 GHz. When the proposed sensor is stretched from 0 to 8 mm along the +x direction, the resonant frequency is shifted from 3.68 GHz to 3.13 GHz. When the proposed sensor is stretched from 0 to 8 mm along the −x direction, the resonant frequency is shifted from 2.03 GHz to 1.78 GHz. Therefore, we can detect stretched length and direction from independent variation of two resonant frequencies.

  20. Laser Spectroscopy of the Fine-Structure Splitting in the 2 PJ 3 Levels of He 4

    Science.gov (United States)

    Zheng, X.; Sun, Y. R.; Chen, J.-J.; Jiang, W.; Pachucki, K.; Hu, S.-M.

    2017-02-01

    The fine-structure splitting in the 2 PJ 3 (J =0 , 1, 2) levels of He 4 is of great interest for tests of quantum electrodynamics and for the determination of the fine-structure constant α . The 2 P0 3 -2 P2 3 and 2 P1 3 -2 P2 3 intervals are measured by laser spectroscopy of the PJ 3 -2 S1 3 transitions at 1083 nm in an atomic beam, and are determined to be 31 908 130.98 ±0.13 kHz and 2 291 177.56 ±0.19 kHz , respectively. Compared with calculations, which include terms up to α5Ry , the deviation for the α -sensitive interval 2 P0 3 -2 P2 3 is only 0.22 kHz. It opens the window for further improvement of theoretical predictions and an independent determination of the fine-structure constant α with a precision of 2 ×10-9 .

  1. Hyperfine and spin-orbit dynamics in GaAs double quantum dots

    Science.gov (United States)

    Shulman, Michael; Nichol, John; Harvey, Shannon; Pal, Arijeet; Halperin, Bertrand; Umansky, Vladimir; Yacoby, Amir

    2015-03-01

    Semiconductor quantum dots provide a unique platform for single-particle physics and many-body quantum mechanics. In particular, understanding the dynamics of a single electron interacting with a nuclear spin bath is key to improving spin-based quantum information processing, since the hyperfine interaction limits the performance of many spin qubits. We probe the electron-nuclear interaction by measuring the splitting at the anti-crossing between the electron singlet (S) and m =1 triplet (T +) states in a GaAs double quantum dot. Using Landau-Zener sweeps, we find that the size of this splitting varies by more than an order of magnitude depending on the magnitude and direction of the external magnetic field. These results are consistent with a competition between the spin orbit interaction and the hyperfine interaction, even though the extracted spin orbit length is much larger than the size of the double quantum dot. We confirm these results by using Landau-Zener sweeps to measure the high-frequency correlations in the S-T + splitting that arise from the Larmor precession of the nuclei. These unexpected results have implications for improving the performance of spin-based quantum information processing, as well as improving our understanding of the central spin problem.

  2. Temperature dependence of the hyperfine interaction at

    Energy Technology Data Exchange (ETDEWEB)

    Lopez-Garcia, Alberto; de la Presa, Patricia; Ayala, Alejandro

    2001-06-01

    The temperature dependence of the quadrupole hyperfine parameters covering the temperature range from 293 to 1173 K was measured at {sup 181}Ta probes in SrHfO{sub 3} by perturbed angular correlation spectroscopy. A fluctuating distribution of quadrupole interactions model was applied to interpret the data. At low temperatures above {approximately}300 K a static, asymmetric, and distributed electric quadrupole interaction was detected. At intermediate temperatures ({approx}600 K) a different quadrupole interaction appears, characterized by a fluctuating distribution of axially symmetric electric field gradient tensors. Above 873 K, the unique presence of a nuclear spin relaxation mechanism shows a second change in the perturbation acting on probes. These changes in the hyperfine interaction are consistent with the structural phase transitions detected by diffraction techniques. The probe effects were also analyzed, comparing {sup 181}Ta with {sup 111}Cd experiments.

  3. HfS, Hyperfine Structure Fitting Tool

    CERN Document Server

    Estalella, Robert

    2016-01-01

    HfS is a tool to fit the hyperfine structure of spectral lines, with multiple velocity components. The HfS_nh3 procedures included in HfS fit simultaneously the hyperfine structure of the NH$_3$ (J,K)= (1,1) and (2,2) transitions, and perform a standard analysis to derive $T_\\mathrm{ex}$, NH$_3$ column density, $T_\\mathrm{rot}$, and $T_\\mathrm{k}$. HfS uses a Monte Carlo approach for fitting the line parameters. Especial attention is paid to the derivation of the parameter uncertainties. HfS includes procedures that make use of parallel computing for fitting spectra from a data cube.

  4. Combined effect of coherent Z exchange and the hyperfine interaction in atomic PNC

    CERN Document Server

    Johnson, W R; Safronova, U I

    2003-01-01

    The nuclear spin-dependent PNC interaction arising from a combination of the hyperfine interaction and the coherent, spin-independent, PNC interaction from Z exchange is evaluated using many-body perturbation theory. For the 6s-7s transition in 133Cs, we obtain a result that is about 60% smaller than that found previously by Bouchiat and Piketty [Phys. Lett. B 269, 195 (1991)]. Applying this result to 133Cs, leads to an increase in the experimental value of nuclear anapole moment and exacerbates differences between constraints on PNC meson coupling constants obtained from the Cs anapole moment and those obtained from other nuclear parity violating experiments. Nuclear spin-dependent PNC dipole matrix elements, including contributions from the combined weak-hyperfine interaction, are also given for the 7s-8s transition in 211Fr and for transitions between ground-state hyperfine levels in K, Rb, Cs, Ba+, Au, Tl, Fr, and Ra+.

  5. Hyperfine and Optical Barium Ion Qubits

    CERN Document Server

    Dietrich, M R; Noel, T; Shu, G; Blinov, B B

    2010-01-01

    State preparation, qubit rotation, and high fidelity readout are demonstrated for two separate \\baseven qubit types. First, an optical qubit on the narrow 6S$_{1/2}$ to 5D$_{5/2}$ transition at 1.76 $\\mu$m is implemented. Then, leveraging the techniques developed there for readout, a ground state hyperfine qubit using the magnetically insensitive transition at 8 GHz is accomplished.

  6. Absorption properties of a driven Doppler-broadened ladder system with hyperfine structure

    Institute of Scientific and Technical Information of China (English)

    吴金辉; 高锦岳

    2002-01-01

    We have studied the absorption spectrum of a Doppler-broadened ladder system, where the highest level is coupled into two middle hyperfine sublevels by a strong coherent field. We find that, when the system is considered as homoge- neous, either two or three spectral components are observed, depending on the detuning of the coherent field. But when the velocity distribution of atoms is considered, we can always observe one electromagnetically induced transparency (EIT) window with high dispersion. So the atomic hyperfine structure cannot be an impediment for obtaining EIT.

  7. Zeeman- and Paschen-Back-effect of the hyperfine structure of the sodium D 2-line

    Science.gov (United States)

    Windholz, L.; Musso, M.

    1988-09-01

    Using high resolution laser-atomic-beam spectroscopy, Zeeman- and Paschen-Back-effects of the hyperfine structure of the sodium resonance lines were studied in magnetic fields up to 280 Gauss without perturbation by cross-over resonances. The observed behaviour of the components of the D 2-line is compared with results of theoretical calculations for the splitting and the relative intensity of each Zeeman-component of the line. Full agreement between theory and experiment can be stated. Additionally, the relative intensities of the components of the D 1-line are given.

  8. Effect of thermal history on Mossbauer signature and hyperfine interaction parameters of copper ferrite

    Energy Technology Data Exchange (ETDEWEB)

    Modi, K. B., E-mail: kunalbmodi2003@yahoo.com; Raval, P. Y.; Dulera, S. V.; Kathad, C. R.; Shah, S. J.; Trivedi, U. N. [Department of Physics, Saurashtra University, Rajkot-360005 (India); Chandra, Usha [High pressure Physics Laboratory, Department of Physics, University of Rajasthan, Jaipur-302004 (India)

    2015-06-24

    Two specimens of copper ferrite, CuFe{sub 2}O{sub 4}, have been synthesized by double sintering ceramic technique with different thermal history i.e. slow cooled and quenched. X-ray diffractometry has confirmed single phase fcc spinel structure for slow cooled sample while tetragonal distortion is present in quenched sample. Mossbauer spectral analysis for slow-cooled copper ferrite reveals super position of two Zeeman split sextets along with paramagnetic singlet in the centre position corresponds to delafossite (CuFeO{sub 2}) phase that is completely absent in quenched sample. The hyperfine interaction parameters are highly influenced by heat treatment employed.

  9. Hyperfine structure in the J = 1-0 transitions of DCO^+, DNC, and HN13C: astronomical observations and quantum-chemical calculations

    Science.gov (United States)

    van der Tak, F. F. S.; Müller, H. S. P.; Harding, M. E.; Gauss, J.

    2009-11-01

    Context: Knowledge of the hyperfine structure of molecular lines is useful for estimating reliable column densities from observed emission, and essential for the derivation of kinematic information from line profiles. Aims: Deuterium bearing molecules are especially useful in this regard, because they are good probes of the physical and chemical structure of molecular cloud cores on the verge of star formation. However, the necessary spectroscopic data are often missing, especially for molecules which are too unstable for laboratory study. Methods: We have observed the ground-state (J = 1{-}0) rotational transitions of DCO^+, HN13C and DNC with the IRAM 30 m telescope toward the dark cloud LDN 1512 which has exceptionally narrow lines permitting hyperfine splitting to be resolved in part. The measured splittings of 50-300 kHz are used to derive nuclear quadrupole and spin-rotation parameters for these species. The measurements are supplemented by high-level quantum-chemical calculations using coupled-cluster techniques and large atomic-orbital basis sets. Results: We find eQq = + 151.12 (400) kHz and CI = -1.12 (43) kHz for DCO^+, eQq = 272.5 (51) kHz for HN13C, and eQq(D) =265.9 (83) kHz and eQq(N) = 288.2 (71) kHz for DNC. The numbers for DNC are consistent with previous laboratory data, while our constants for DCO+ are somewhat smaller than previous results based on astronomical data. For both DCO+ and DNC, our results are more accurate than previous determinations. Our results are in good agreement with the corresponding best theoretical estimates, which amount to eQq = 156.0 kHz and CI = -0.69 kHz for DCO^+, eQq = 279.5 kHz for HN13C, and eQq(D) = 257.6 kHz and eQq(N) = 309.6 kHz for DNC. We also derive updated rotational constants for HN13C: B = 43 545.6000 (47) MHz and D = 93.7 (20) kHz. Conclusions: The hyperfine splittings of the DCO^+, DNC and HN13C J = 1{-}0 lines range over 0.47-1.28 km s-1, which is comparable to typical line widths in pre

  10. Hyperfine Stark effect of shallow donors in silicon

    Science.gov (United States)

    Pica, Giuseppe; Wolfowicz, Gary; Urdampilleta, Matias; Thewalt, Mike L. W.; Riemann, Helge; Abrosimov, Nikolai V.; Becker, Peter; Pohl, Hans-Joachim; Morton, John J. L.; Bhatt, R. N.; Lyon, S. A.; Lovett, Brendon W.

    2014-11-01

    We present a complete theoretical treatment of Stark effects in bulk doped silicon, whose predictions are supported by experimental measurements. A multivalley effective mass theory, dealing nonperturbatively with valley-orbit interactions induced by a donor-dependent central cell potential, allows us to obtain a very reliable picture of the donor wave function within a relatively simple framework. Variational optimization of the 1 s donor binding energies calculated with a new trial wave function, in a pseudopotential with two fitting parameters, allows an accurate match of the experimentally determined donor energy levels, while the correct limiting behavior for the electronic density, both close to and far from each impurity nucleus, is captured by fitting the measured contact hyperfine coupling between the donor nuclear and electron spin. We go on to include an external uniform electric field in order to model Stark physics: with no extra ad hoc parameters, variational minimization of the complete donor ground energy allows a quantitative description of the field-induced reduction of electronic density at each impurity nucleus. Detailed comparisons with experimental values for the shifts of the contact hyperfine coupling reveal very close agreement for all the donors measured (P, As, Sb, and Bi). Finally, we estimate field ionization thresholds for the donor ground states, thus setting upper limits to the gate manipulation times for single qubit operations in Kane-like architectures: the Si:Bi system is shown to allow for A gates as fast as ≈10 MHz.

  11. Zeeman- and Paschen-Back-effect of the hyperfine structure of the sodium D 1-line

    Science.gov (United States)

    Windholz, L.

    1985-06-01

    Using high-resolution laser-atomic-beam spectroscopy, Zeeman- and Paschen-Back-effects of the hyperfine structure of the sodium resonance lines were studied in fields up to app. 280 G. The results derived for the D 1-line are given in graphical form and show clearly the change in the coupling of J and I of the upper level.

  12. Classroom Modified Split-Root Technique and Its Application in a Plant Habitat Selection Experiment at the College Level

    Science.gov (United States)

    Elliott, Shannon S.; Winter, Peggy A.

    2011-01-01

    The split-root technique produces a plant with two equal root masses. Traditionally, the two root masses of the single plant are cultivated in adjacent pots with or without roots from competitors for the purpose of elucidating habitat preferences. We have tailored this technology for the classroom, adjusting protocols to match resources and time…

  13. Nagaoka's atomic model and hyperfine interactions.

    Science.gov (United States)

    Inamura, Takashi T

    2016-01-01

    The prevailing view of Nagaoka's "Saturnian" atom is so misleading that today many people have an erroneous picture of Nagaoka's vision. They believe it to be a system involving a 'giant core' with electrons circulating just outside. Actually, though, in view of the Coulomb potential related to the atomic nucleus, Nagaoka's model is exactly the same as Rutherford's. This is true of the Bohr atom, too. To give proper credit, Nagaoka should be remembered together with Rutherford and Bohr in the history of the atomic model. It is also pointed out that Nagaoka was a pioneer of understanding hyperfine interactions in order to study nuclear structure.

  14. Hyperfine structure studies with the COMPLIS facility

    CERN Document Server

    Crawford, J E; Le Blanc, F; Lunney, M D; Obert, J; Oms, J; Putaux, J C; Roussière, B; Sauvage, J; Zemlyanoi, S G; Verney, D; Pinard, J; Cabaret, L A; Duong, H T; Huber, G; Krieg, M; Sebastian, V; Girod, M; Peru, S; Genevey, J; Ibrahim, F; Lettry, Jacques

    1998-01-01

    COMPLIS is an experimental facility designed to carry out spectroscopic studies on radioisotopes produced by disintegration of elements available at CERN's Booster-ISOLDE on-line isotope separator. During recent series of experimental runs, hyperfine structure measurements have yielded information on nuclear moments and deformations of platinum and iridium isotopes, For the first time, population by alpha -decay from Hg was exploited to investigate /sup 178/-/sup 181/Pt-the most neutron-deficient Pt isotopes yet studied. Successful measurements have recently been carried out on /sup 182-189/Ir. (10 refs).

  15. Hyperfine Structure and Isotope Shifts in Dy II

    Directory of Open Access Journals (Sweden)

    Dylan F. Del Papa

    2017-01-01

    Full Text Available Using fast-ion-beam laser-fluorescence spectroscopy (FIBLAS, we have measured the hyperfine structure (hfs of 14 levels and an additional four transitions in Dy II and the isotope shifts (IS of 12 transitions in the wavelength range of 422–460 nm. These are the first precision measurements of this kind in Dy II. Along with hfs and IS, new undocumented transitions were discovered within 3 GHz of the targeted transitions. These atomic data are essential for astrophysical studies of chemical abundances, allowing correction for saturation and the effects of blended lines. Lanthanide abundances are important in diffusion modeling of stellar interiors, and in the mechanisms and history of nucleosynthesis in the universe. Hfs and IS also play an important role in the classification of energy levels, and provide a benchmark for theoretical atomic structure calculations.

  16. Level-crossing spectroscopy of nitrogen-vacancy centers in diamond: sensitive detection of paramagnetic defect centers

    CERN Document Server

    Anishchik, S V; Ivanov, K L

    2016-01-01

    We report a magnetic field dependence of fluorescence of diamond single crystals containing NV$^-$ centers. In such spectra, numerous sharp lines are found, which correspond to Level Anti-Crossings (LACs) in coupled spins systems comprising an NV$^-$ center. Theoretical modeling of such "LAC-spectra" enables characterization of paramagnetic defect centers and determination of their magnetic resonance parameters, such as zero-field splitting and hyperfine coupling constants. The outlined method thus enables sensitive detection of paramagnetic impurities in diamond crystals.

  17. Polarized scattering with Paschen-Back effect, hyperfine structure, and partial frequency redistribution in magnetized stellar atmospheres

    Energy Technology Data Exchange (ETDEWEB)

    Sowmya, K.; Nagendra, K. N.; Sampoorna, M. [Indian Institute of Astrophysics, Koramangala, Bengaluru (India); Stenflo, J. O., E-mail: ksowmya@iiap.res.in, E-mail: knn@iiap.res.in, E-mail: sampoorna@iiap.res.in, E-mail: stenflo@astro.phys.ethz.ch [Institute of Astronomy, ETH Zurich, CH-8093 Zurich (Switzerland)

    2014-05-10

    F-state interference significantly modifies the polarization produced by scattering processes in the solar atmosphere. Its signature in the emergent Stokes spectrum in the absence of magnetic fields is depolarization in the line core. In the present paper, we derive the partial frequency redistribution (PRD) matrix that includes interference between the upper hyperfine structure states of a two-level atom in the presence of magnetic fields of arbitrary strengths. The theory is applied to the Na I D{sub 2} line that is produced by the transition between the lower J = 1/2 and upper J = 3/2 states which split into F states because of the coupling with the nuclear spin I{sub s} = 3/2. The properties of the PRD matrix for the single-scattering case is explored, in particular, the effects of the magnetic field in the Paschen-Back regime and their usefulness as a tool for the diagnostics of solar magnetic fields.

  18. Splitting Descartes

    DEFF Research Database (Denmark)

    Schilhab, Theresa

    2007-01-01

    Kognition og Pædagogik vol. 48:10-18. 2003 Short description : The cognitivistic paradigm and Descartes' view of embodied knowledge. Abstract: That the philosopher Descartes separated the mind from the body is hardly news: He did it so effectively that his name is forever tied to that division....... But what exactly is Descartes' point? How does the Kartesian split hold up to recent biologically based learning theories?...

  19. Hyperfine structure in the J = 1-0 transitions of DCO+, DNC, and HN13C: astronomical observations and quantum-chemical calculations

    CERN Document Server

    van der Tak, Floris; Harding, Michael; Gauss, Jürgen

    2009-01-01

    We have observed the rotational ground-state (J = 1-0) transitions of DCO+, HN13C and DNC with the IRAM 30m telescope toward the dark cloud LDN 1512 which has exceptionally narrow lines permitting hyperfine splitting to be resolved in part. The measured splittings of 50-300 kHz are used to derive nuclear quadrupole and spin-rotation parameters for these species. The measurements are supplemented by high-level quantum-chemical calculations using coupled-cluster techniques and large atomic-orbital basis sets. We find eQq = +151.12 (400) kHz and C_I = -1.12 (43) kHz for DCO+, eQq = 272.5 (51) kHz for HN13C, and eQq(D) = 265.9 (83) kHz and eQq(N) = 288.2 (71) kHz for DNC. The numbers for DNC are consistent with previous laboratory data, while our constants for DCO+ are somewhat smaller than previous results based on astronomical data. For both DCO+ and DNC, our results are more accurate than previous determinations. Our results are in good agreement with the corresponding best theoretical estimates. We also deriv...

  20. Investigations of the ground-state hyperfine atomic structure and beta decay measurement prospects of 21Na with improved laser trapping techniques

    Energy Technology Data Exchange (ETDEWEB)

    Rowe, Mary Anderson [Univ. of California, Berkeley, CA (United States)

    1999-05-01

    This thesis describes an experiment in which a neutral atom laser trap loaded with radioactive 21Na was improved and then used for measurements. The sodium isotope (half-life=22 sec) is produced on line at the 88 in. cyclotron at Lawrence Berkeley National Laboratory. The author developed an effective magnesium oxide target system which is crucial to deliver a substantive beam of 21Na to the experiment. Efficient manipulation of the 21Na beam with lasers allowed 30,000 atoms to be contained in a magneto-optical trap. Using the cold trapped atoms, the author measured to high precision the hyperfine splitting of the atomic ground state of 21Na. She measured the 3S1/2(F=1,m=0)-3S1/2(F=2,m=0) atomic level splitting of 21Na to be 1,906,471,870±200 Hz. Additionally, she achieved initial detection of beta decay from the trap and evaluated the prospects of precision beta decay correlation studies with trapped atoms.

  1. Fine- and hyperfine structure investigations of even configuration system of atomic terbium

    Science.gov (United States)

    Stefanska, D.; Elantkowska, M.; Ruczkowski, J.; Furmann, B.

    2017-03-01

    In this work a parametric study of the fine structure (fs) and the hyperfine structure (hfs) for the even-parity configurations of atomic terbium (Tb I) is presented, based in considerable part on the new experimental results. Measurements on 134 spectral lines were performed by laser induced fluorescence (LIF) in a hollow cathode discharge lamp; on this basis, the hyperfine structure constants A and B were determined for 52 even-parity levels belonging to the configurations 4f85d6s2, 4f85d26s or 4f96s6p; in all the cases those levels were involved in the transitions investigated as the lower levels. For 40 levels the hfs was examined for the first time, and for the remaining 12 levels the new measurements supplement our earlier results. As a by-product, also preliminary values of the hfs constants for 84 odd-parity levels were determined (the investigations of the odd-parity levels system in the terbium atom are still in progress). This huge amount of new experimental data, supplemented by our earlier published results, were considered for the fine and hyperfine structure analysis. A multi-configuration fit of 7 configurations was performed, taking into account second-order of perturbation theory, including the effects of closed shell-open shell excitations. Predicted values of the level energies, as well as of magnetic dipole and electric quadrupole hyperfine structure constants A and B, are quoted in cases when no experimental values are available. By combining our experimental data with our own semi-empirical procedure it was possible to identify correctly the lower and upper level of the line 544.1440 nm measured by Childs with the use of the atomic-beam laser-rf double-resonance technique (Childs, J Opt Soc Am B 9;1992:191-6).

  2. Strain and electric field control of hyperfine interactions for donor spin qubits in silicon

    Science.gov (United States)

    Usman, M.; Hill, C. D.; Rahman, R.; Klimeck, G.; Simmons, M. Y.; Rogge, S.; Hollenberg, L. C. L.

    2015-06-01

    Control of hyperfine interactions is a fundamental requirement for quantum computing architecture schemes based on shallow donors in silicon. However, at present, there is lacking an atomistic approach including critical effects of central-cell corrections and nonstatic screening of the donor potential capable of describing the hyperfine interaction in the presence of both strain and electric fields in realistically sized devices. We establish and apply a theoretical framework, based on atomistic tight-binding theory, to quantitatively determine the strain and electric-field-dependent hyperfine couplings of donors. Our method is scalable to millions of atoms, and yet captures the strain effects with an accuracy level of DFT method. Excellent agreement with the available experimental data sets allow reliable investigation of the design space of multiqubit architectures, based on both strain only as well as hybrid (strain + field) control of qubits. The benefits of strain are uncovered by demonstrating that a hybrid control of qubits based on (001) compressive strain and in-plane (100 or 010) fields results in higher gate fidelities and or faster gate operations, for all of the four donor species considered (P, As, Sb, and Bi). The comparison between different donor species in strained environments further highlights the trends of hyperfine shifts, providing predictions where no experimental data exists. While faster gate operations are realizable with in-plane fields for P, As, and Sb donors, only for the Bi donor, our calculations predict faster gate response in the presence of both in-plane and out-of-plane fields, truly benefiting from the proposed planar field control mechanism of the hyperfine interactions.

  3. Electrical detection of hyperfine interactions in silicon

    Energy Technology Data Exchange (ETDEWEB)

    Hoehne, Felix

    2012-12-15

    The main focus of this work was the measurement of hyperfine interactions of defects in silicon using EDMR. We combined the high sensitivity of EDMR when compared to conventional ESR with the two most commonly used methods for the measurement of hyperfine interactions: ESEEM and ENDOR. We first demonstrated the electrical detection of ESEEM by measuring the hyperfine interactions of {sup 31}P donors in Si:P with {sup 29}Si nuclear spins. We then apply EDESEEM to P{sub b0} defects at the Si/SiO{sub 2} interface. In isotopically engineered, we observe an ESEEM modulation with a characteristic beating caused by {sup 29}Si nuclei at 4th and 5th nearest neighbor lattice sites. Then we combine pulsed ENDOR with the high sensitivity of EDMR (EDENDOR). First we demonstrate the measurement of {sup 31}P nuclear spin hyperfine transitions and the coherent manipulation and readout of the {sup 31}P nuclear spins under continuous illumination with above bandgap light. We further show that the EDENDOR method can be greatly improved by switching off the illumination during the microwave and rf pulses. This improves the signal-to-noise ratio by two orders of magnitude and removes the non-resonant background induced by the strong rf pulse allowing to measure ENDOR with a sensitivity <3000 nuclear spins. We apply EDENDOR to the {sup 31}P-P{sub b0} spin system and the {sup 31}P-SL1 spin system allowing us to compare the hyperfine interactions of bulk and interface-near donors. The pulsed illumination also makes spectroscopy of the {sup 31}P{sup +} nuclear spin possible, which due to its long coherence time of 18 ms compared to 280 {mu}s for the {sup 31}P{sub 0} nuclear spin, might be a candidate for a nuclear spin memory. In the last part, we devise a scheme for the hyperpolarization of {sup 31}P nuclei by combining pulsed optical excitation and pulsed ENDOR and demonstrate a {sup 31}P nuclear spin polarization of more than 50%. Crucial for these experiments was the development of a

  4. Ro-vibrational averaging of the isotropic hyperfine coupling constant for the methyl radical

    Energy Technology Data Exchange (ETDEWEB)

    Adam, Ahmad Y.; Jensen, Per, E-mail: jensen@uni-wuppertal.de [Fakultät Mathematik und Naturwissenschaften, Physikalische und Theoretische Chemie, Bergische Universität Wuppertal, D-42097 Wuppertal (Germany); Yachmenev, Andrey; Yurchenko, Sergei N. [Department of Physics and Astronomy, University College London, Gower Street, London WC1E 6BT (United Kingdom)

    2015-12-28

    We present the first variational calculation of the isotropic hyperfine coupling constant of the carbon-13 atom in the CH{sub 3} radical for temperatures T = 0, 96, and 300 K. It is based on a newly calculated high level ab initio potential energy surface and hyperfine coupling constant surface of CH{sub 3} in the ground electronic state. The ro-vibrational energy levels, expectation values for the coupling constant, and its temperature dependence were calculated variationally by using the methods implemented in the computer program TROVE. Vibrational energies and vibrational and temperature effects for coupling constant are found to be in very good agreement with the available experimental data. We found, in agreement with previous studies, that the vibrational effects constitute about 44% of the constant’s equilibrium value, originating mainly from the large amplitude out-of-plane bending motion and that the temperature effects play a minor role.

  5. Precise measurement of hyperfine intervals using avoided crossing of dressed states

    CERN Document Server

    Rapol, U D; Rapol, Umakant D.; Natarajan, Vasant

    2002-01-01

    We demonstrate a technique for precisely measuring hyperfine intervals in alkali atoms. The atoms form a three-level $\\Lambda$ system in the presence of a strong control laser and a weak probe laser. The dressed states created by the control laser show significant linewidth reduction. We have developed a technique for Doppler-free spectroscopy that enables the separation between the dressed states to be measured with high accuracy even in room-temperature atoms. The states go through an avoided crossing as the detuning of the control laser is changed from positive to negative. By studying the separation as a function of detuning, the center of the level-crossing diagram is determined with high precision, which yields the hyperfine interval. Using room-temperature Rb vapor, we obtain a precision of 44 kHz. This is a significant improvement over the current precision of ~ 1 MHz.

  6. Hyperfine and crystal field interactions in multiferroic HoCrO3

    Science.gov (United States)

    Kumar, C. M. N.; Xiao, Y.; Nair, H. S.; Voigt, J.; Schmitz, B.; Chatterji, T.; Jalarvo, N. H.; Brückel, Th

    2016-11-01

    We report a comprehensive specific heat and inelastic neutron scattering study to explore the possible origin of multiferroicity in HoCrO3. We have performed specific heat measurements in the temperature range 100 mK-290 K and inelastic neutron scattering measurements were performed in the temperature range 1.5-200 K. From the specific heat data we determined hyperfine splitting at 22.5(2) μeV and crystal field transitions at 1.379(5) meV, 10.37(4) meV, 15.49(9) meV and 23.44(9) meV, indicating the existence of strong hyperfine and crystal field interactions in HoCrO3. Further, an effective hyperfine field is determined to be 600(3) T. The quasielastic scattering observed in the inelastic scattering data and a large linear term γ =6.3(8) mJ mol-1  K-2 in the specific heat is attributed to the presence of short range exchange interactions, which is understood to be contributing to the observed ferroelectricity. Further the nuclear and magnetic entropies were computed to be, ˜17.2 Jmol-1 K-1 and  ˜34 Jmol-1 K-1, respectively. The entropy values are in excellent agreement with the limiting theoretical values. An anomaly is observed in the peak position of the temperature dependent crystal field spectra around 60 K, at the same temperature an anomaly in the pyroelectric current is reported. From this we could elucidate a direct correlation between the crystal electric field excitations of Ho3+ and ferroelectricity in HoCrO3. Our present study, along with recent reports, confirm that HoCrO3, and RCrO3 (R  =  rare earth) in general, possess more than one driving force for the ferroelectricity and multiferroicity.

  7. Quantum Theory of Hyperfine Structure Transitions in Diatomic Molecules.

    Science.gov (United States)

    Klempt, E.; And Others

    1979-01-01

    Described is an advanced undergraduate laboratory experiment in which radio-frequency transitions between molecular hyperfine structure states may be observed. Aspects of the quantum theory applied to the analysis of this physical system, are discussed. (Authors/BT)

  8. Spin-torsion effects in the hyperfine structure of methanol

    Energy Technology Data Exchange (ETDEWEB)

    Coudert, L. H., E-mail: laurent.coudert@lisa.u-pec.fr; Gutlé, C. [Laboratoire Inter-Universitaire des Systèmes Atmosphériques, UMR 7583 CNRS-Universités Paris Est Créteil et Paris Diderot, 61 Avenue du Général de Gaulle, 94010 Créteil Cedex (France); Huet, T. R. [Laboratoire de Physique des Lasers, Atomes et Molécules, UMR 8523 CNRS-Université Lille 1, Bâtiment P5, 59655 Villeneuve d’Ascq Cedex (France); Grabow, J.-U. [Institut für Physikalische Chemie, Callinstrasse 3–3a, 30167 Hannover (Germany); Levshakov, S. A. [St. Petersburg Electrotechnical University “LETI,” 197376 St. Petersburg (Russian Federation)

    2015-07-28

    The magnetic hyperfine structure of the non-rigid methanol molecule is investigated experimentally and theoretically. 12 hyperfine patterns are recorded using molecular beam microwave spectrometers. These patterns, along with previously recorded ones, are analyzed in an attempt to evidence the effects of the magnetic spin-torsion coupling due to the large amplitude internal rotation of the methyl group [J. E. M. Heuvel and A. Dymanus, J. Mol. Spectrosc. 47, 363 (1973)]. The theoretical approach setup to analyze the observed data accounts for this spin-torsion in addition to the familiar magnetic spin-rotation and spin-spin interactions. The theoretical approach relies on symmetry considerations to build a hyperfine coupling Hamiltonian and spin-rotation-torsion wavefunctions compatible with the Pauli exclusion principle. Although all experimental hyperfine patterns are not fully resolved, the line position analysis yields values for several parameters including one describing the spin-torsion coupling.

  9. Hyperfine Interactions in Iron Meteorites: Comparative Study by Moessbauer Spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Oshtrakh, M. I., E-mail: oshtrakh@mail.utnet.ru [Ural State Technical University - UPI, Faculty of Physical Techniques and Devices for Quality Control (Russian Federation); Milder, O. B. [Ural State Technical University - UPI, Faculty of Experimental Physics (Russian Federation); Grokhovsky, V. I. [Ural State Technical University - UPI, Faculty of Physical Techniques and Devices for Quality Control (Russian Federation); Semionkin, V. A. [Ural State Technical University - UPI, Faculty of Experimental Physics (Russian Federation)

    2004-11-15

    The iron meteorites Sikhote-Alin, Bilibino, Chinga and Dronino with different Ni concentration and terrestrial age were studied by Moessbauer spectroscopy. Different Moessbauer hyperfine parameters were determined for studied meteorites and possible Fe-Ni phases were supposed.

  10. Interpretation of quasi-Fermi level splitting in Cu(Ga,In)Se{sub 2}-absorbers by confocally recorded spectral luminescence and numerical modeling

    Energy Technology Data Exchange (ETDEWEB)

    Knabe, Sebastian [Institute of Physics, CvO University Oldenburg (Germany)], E-mail: levent.guetay@uni-oldenburg.de; Guetay, Levent; Bauer, Gottfried H. [Institute of Physics, CvO University Oldenburg (Germany)

    2009-02-02

    Spectral room temperature photoluminescence (pl) of polycrystalline Cu(In,Ga)Se{sub 2} films (CIGSe) is evaluated with respect to optoelectronic properties and in particular for the determination of the splitting of quasi-Fermi levels (E{sub Fn} - E{sub Fp}). For lateral resolution of {<=} 1 {mu}m a confocal pl-setup is used. The depth profile of the excess carrier densities determining the rates of radiative transitions strongly govern the spectral pl-shape which has been numerically modeled with a matrix transfer formalism. In this optical approach we discriminate for wave propagation and attenuation in a multilayer system between a plane-wave ansatz and a 3D-spherical formalism, depending on excitation area large or small/similar compared to the thickness of the absorber. In both cases re-absorption of photons in energetic regimes with absorption approaches unity, from which the splitting of the quasi-Fermi levels is preferentially deduced, substantially influence the spectral luminescence signal. For heterojunctions usually located at the light entrance side of the device our evaluation with good agreement reflects (E{sub Fn} - E{sub Fp}) in the vicinity of the barrier and thus indicates the maximum achievable open circuit voltage of the finally processed diode. Departures of the spectral pl from the idealized Bose-term signalize unfavorable carrier profiles and a depth dependence of optoelectronic absorber properties.

  11. Hyperfine Coherence in the Presence of Spontaneous Photon Scattering

    CERN Document Server

    Ozeri, R; Jost, J D; De Marco, B L; Ben-Kish, A; Blakestad, B R; Britton, J L; Chiaverini, J; Itano, W M; Hume, D; Leibfried, D; Rosenband, T; Schmidt, P; Wineland, D J

    2005-01-01

    The coherence of a hyperfine-state superposition of a trapped $^{9}$Be$^+$ ion in the presence of off-resonant light is experimentally studied. It is shown that Rayleigh elastic scattering of photons that does not change state populations also does not affect coherence. Coherence times exceeding the average scattering time of 19 photons are observed. This result implies that, with sufficient control over its parameters, laser light can be used to manipulate hyperfine-state superpositions with very little decoherence.

  12. Hyperfine selectivity using multiquantum electron-nuclear-electron triple resonance

    Science.gov (United States)

    Christidis, T. C.; Mchaourab, Hassane S.; Hyde, James S.

    1996-06-01

    Hyperfine selectivity is demonstrated in a continuous wave electron-nuclear double resonance (ENDOR) experiment. A multiquantum electron-electron double resonance (ELDOR) signal is monitored as a function of the nuclear radio frequency. The signs and relative intensities of the ENDOR lines permit separating the case where both ELDOR and ENDOR frequencies match hyperfine couplings from the cases where this condition is not satisfied.

  13. Thermal and nuclear hyperfine properties of Ho(OH)3

    Science.gov (United States)

    Karmakar, S.

    1985-05-01

    A reasonable explanation for the findings of Catanese and Meissner [Phys. Rev. B 8, 2071 (1973)] regarding the (hyperfine) heat capacity in the low-temperature region of Ho(OH)3 is given. The Schottky specific heat in the high-temperature region observed calorimetrically by Chirico et al. [J. Chem. Thermodyn. 13, 1092 (1981)] explained satisfactorily. Nuclear hyperfine constants for Ho3+ ions in Ho(OH)3 are determined.

  14. Determination of the hyperfine coupling constant of the cesium 7S1/2 state

    Science.gov (United States)

    Yang, Guang; Wang, Jie; Yang, Baodong; Wang, Junmin

    2016-08-01

    We report the hyperfine splitting (HFS) measurement of the cesium (Cs) 7S1/2 state by optical-optical double-resonance spectroscopy with the Cs 6S1/2-6P3/2-7S1/2 (852 nm  +  1470 nm) ladder-type system. The HFS frequency calibration is performed by employing a phase-type waveguide electro-optic modulator together with a stable confocal Fabry-Perot cavity. From the measured HFS between the F″  =  3 and F″  =  4 manifolds of the Cs 7S1/2 state (HFS  =  2183.273  ±  0.062 MHz), we have determined the magnetic dipole hyperfine coupling constant (A  =  545.818  ±  0.016 MHz), which is in good agreement with the previous work but much more precise.

  15. Hyperfine coupling of hole and nuclear spins in symmetric (111)-grown GaAs quantum dots

    Science.gov (United States)

    Vidal, M.; Durnev, M. V.; Bouet, L.; Amand, T.; Glazov, M. M.; Ivchenko, E. L.; Zhou, P.; Wang, G.; Mano, T.; Kuroda, T.; Marie, X.; Sakoda, K.; Urbaszek, B.

    2016-09-01

    In self-assembled III-V semiconductor quantum dots, valence holes have longer spin coherence times than the conduction electrons, due to their weaker coupling to nuclear spin bath fluctuations. Prolonging hole spin stability relies on a better understanding of the hole to nuclear spin hyperfine coupling which we address both in experiment and theory in the symmetric (111) GaAs/AlGaAs droplet dots. In magnetic fields applied along the growth axis, we create a strong nuclear spin polarization detected through the positively charged trion X+ Zeeman and Overhauser splittings. The observation of four clearly resolved photoluminescence lines—a unique property of the (111) nanosystems—allows us to measure separately the electron and hole contribution to the Overhauser shift. The hyperfine interaction for holes is found to be about five times weaker than that for electrons. Our theory shows that this ratio depends not only on intrinsic material properties but also on the dot shape and carrier confinement through the heavy-hole mixing, an opportunity for engineering the hole-nuclear spin interaction by tuning dot size and shape.

  16. First Principles Determination of Hyperfine Parameters on fcc-Fe{sub 8}X (X C, N) Arrangements

    Energy Technology Data Exchange (ETDEWEB)

    Peltzer y Blanca, E. L. [UNLP, Grupo de Estudio de Materiales y Dispositivos Electronicos (GEMyDE), Facultad de Ingenieria (Argentina); Desimoni, J. [UNLP, Departamento de Fisica, Facultad de Ciencias Exactas (Argentina); Christensen, N. E. [Aarhus University, Department of Physics and Astronomy (Denmark)

    2005-02-15

    In order to investigate some of the fundamental physical properties of the fcc-FeX (X = C, N) austenite solid solutions, we compare the hyperfine parameters obtained by Moessbauer {sup 57}Fe spectrometry and those obtained by the full-potential linear augmented-plane wave (FLAPW) method. We have focused the study on isomer shifts and quadrupole splittings at Fe sites obtained by FLAPW assuming an Fe{sub 8}X structure to sketch the austenite. In the present work, we will discuss this point and compare the results of the calculations with experimental data.

  17. Moessbauer hyperfine spectra of DyCo/sub 2/Si/sub 2/

    Energy Technology Data Exchange (ETDEWEB)

    Boge, M.; Chappert, J. (CEA Centre d' Etudes Nucleaires de Grenoble, 38 (France). Dept. de Recherche Fondamentale); Asch, L.; Kalvius, G.M. (Technische Univ. Muenchen, Garching (Germany, F.R.). Fakultaet fuer Physik); Gal, J. (Israel Atomic Energy Commission, Beersheba. Nuclear Research Center-Negev); Goerlich, E.A. (Uniwersytet Jagiellonski, Krakow (Poland). Inst. Fizyki)

    1983-12-01

    Moessbauer spectra of /sup 161/Dy in DyCo/sub 2/Si/sub 2/ were taken between 4.2 K and 78 K. The tetragonal intermetallic has a Neel temperature of Tsub(N)=21 K. Up to 25 K spectra are characterized by extremely slow electronic relaxation, precluding the usual collapse of hyperfine splitting on approaching Tsub(N). Between Tsub(N) and 78 K relaxation spectra are seen. The most unusual feature is a slow, steady decrease of Bsub(hf) and e/sup 2/qQ with temperature. It is suggested that this arises from changes in the wave function of the electronic ground state by influences of the molecular and the crystalline electric fields.

  18. High precision hyperfine measurements in Bismuth challenge bound-state strong-field QED

    Science.gov (United States)

    Ullmann, Johannes; Andelkovic, Zoran; Brandau, Carsten; Dax, Andreas; Geithner, Wolfgang; Geppert, Christopher; Gorges, Christian; Hammen, Michael; Hannen, Volker; Kaufmann, Simon; König, Kristian; Litvinov, Yuri A.; Lochmann, Matthias; Maaß, Bernhard; Meisner, Johann; Murböck, Tobias; Sánchez, Rodolfo; Schmidt, Matthias; Schmidt, Stefan; Steck, Markus; Stöhlker, Thomas; Thompson, Richard C.; Trageser, Christian; Vollbrecht, Jonas; Weinheimer, Christian; Nörtershäuser, Wilfried

    2017-05-01

    Electrons bound in highly charged heavy ions such as hydrogen-like bismuth 209Bi82+ experience electromagnetic fields that are a million times stronger than in light atoms. Measuring the wavelength of light emitted and absorbed by these ions is therefore a sensitive testing ground for quantum electrodynamical (QED) effects and especially the electron-nucleus interaction under such extreme conditions. However, insufficient knowledge of the nuclear structure has prevented a rigorous test of strong-field QED. Here we present a measurement of the so-called specific difference between the hyperfine splittings in hydrogen-like and lithium-like bismuth 209Bi82+,80+ with a precision that is improved by more than an order of magnitude. Even though this quantity is believed to be largely insensitive to nuclear structure and therefore the most decisive test of QED in the strong magnetic field regime, we find a 7-σ discrepancy compared with the theoretical prediction.

  19. Combined effect of coherent Z exchange and the hyperfine interaction in atomic PNC

    Science.gov (United States)

    Johnson, W. R.; Safronova, M. S.; Safronova, U. I.

    2003-05-01

    The nuclear spin-dependent PNC interaction arising from a combination of the hyperfine interaction and the coherent, spin-independent, PNC interaction from Z exchange is evaluated using many-body perturbation theory. For the 6s_1/2-7s_1/2 transition in ^133Cs, we obtain a result that is about 60% smaller than that found previously by Bouchiat and Piketty [Phys. Lett. B series 269, 195 (1991)]. Applying this result to ^133Cs, leads to an increase in the experimental value of nuclear anapole moment and exacerbates differences between constraints on PNC meson coupling constants obtained from the Cs anapole moment and those obtained from other nuclear parity violating experiments. Nuclear spin-dependent PNC dipole matrix elements, including contributions from the combined weak-hyperfine interaction, are also given for the 7s_1/2-8s_1/2 transition in ^211Fr and for transitions between ground-state hyperfine levels in K, Rb, Cs, Ba^+, Au, Tl, Fr, and Ra^+.

  20. Stochastic hyperfine interactions modeling library-Version 2

    Science.gov (United States)

    Zacate, Matthew O.; Evenson, William E.

    2016-02-01

    The stochastic hyperfine interactions modeling library (SHIML) provides a set of routines to assist in the development and application of stochastic models of hyperfine interactions. The library provides routines written in the C programming language that (1) read a text description of a model for fluctuating hyperfine fields, (2) set up the Blume matrix, upon which the evolution operator of the system depends, and (3) find the eigenvalues and eigenvectors of the Blume matrix so that theoretical spectra of experimental techniques that measure hyperfine interactions can be calculated. The optimized vector and matrix operations of the BLAS and LAPACK libraries are utilized. The original version of SHIML constructed and solved Blume matrices for methods that measure hyperfine interactions of nuclear probes in a single spin state. Version 2 provides additional support for methods that measure interactions on two different spin states such as Mössbauer spectroscopy and nuclear resonant scattering of synchrotron radiation. Example codes are provided to illustrate the use of SHIML to (1) generate perturbed angular correlation spectra for the special case of polycrystalline samples when anisotropy terms of higher order than A22 can be neglected and (2) generate Mössbauer spectra for polycrystalline samples for pure dipole or pure quadrupole transitions.

  1. Anomalous hyperfine coupling and nuclear magnetic relaxation in Weyl semimetals

    Science.gov (United States)

    Okvátovity, Zoltán; Simon, Ferenc; Dóra, Balázs

    2016-12-01

    The electron-nuclear hyperfine interaction shows up in a variety of phenomena including, e.g., NMR studies of correlated states and spin decoherence effects in quantum dots. Here we focus on the hyperfine coupling and the NMR spin relaxation time T1 in Weyl semimetals. Since the density of states in Weyl semimetals varies with the square of the energy around the Weyl point, a naive power counting predicts a 1 /T1T ˜E4 scaling, with E the maximum of temperature (T ) and chemical potential. By carefully investigating the hyperfine interaction between nuclear spins and Weyl fermions, we find that while its spin part behaves conventionally, its orbital part diverges unusually, with the inverse of the energy around the Weyl point. Consequently, the nuclear spin relaxation rate scales in a graphenelike manner as 1 /T1T ˜E2ln(E /ω0) , with ω0 the nuclear Larmor frequency. This allows us to identify an effective hyperfine coupling constant, which is tunable by gating or doping. This is relevant for the decoherence effect in spintronics devices and double quantum dots, where hyperfine coupling is the dominant source of spin-blockade lifting.

  2. Van der Waals interaction between ground state atoms and perfect surface of a metal and calculation of C3 in hyperfine atomic levels%基态原子与理想金属Au表面间的范德瓦尔斯作用及超精细能级C3的估算

    Institute of Scientific and Technical Information of China (English)

    魏奶萍; 李莉; 张相武; 张彦鹏; 李院院; 徐可为

    2014-01-01

    Van der Waals (vdW)interaction between alkali atoms and perfect surface of a metal Au is investigated. Taking into account the contribution to vdW from the electric quadruple,a theoretical model is presented to calcu-late C3 values of the vdW interaction between hyperfine levels of alkali atoms and perfect surface of a metal.C3 val-ues corresponding to hyperfine levels of 85 Rb and 133 Cs are calculated,where C3 values of 52 S1/2 (F=2)and 52 S1/2 (F=3)for 85 Rb are 2.2409KHzμm3 and 2.2425 KHzμm3 ,respectively,while 62 S1/2 (F=3)and 62 S1/2 (F=4)for 133 Cs 2.4480 KHzμm3 and 2.4538KHzμm3 .It is also shown that,the greater the F,the larger the C3 ,and the stronger the vdW interaction when z does not change,where z is the distance of an atom from the metal surface. This research on atomic imprisoned and quantum reflection from the dielectric surface has certain significance.%研究了基态碱金属原子与理想金属Au表面间的范德瓦尔斯(vdW)作用.通过分析电四极跃迁对vdW的贡献,构建了计算碱金属原子的超精细能级与理想金属表面间vdW作用系数C3的理论模型.以85 Rb、133 Cs为例,计算了其基态原子超精细能级的C3系数.其中85 Rb:52 S1/2(F=2)及52 S1/2(F=3)对应的C3系数分别为:2.2409KHzμm3及2.2425KHzμm3;133 Cs:62 S1/2(F=3)及62 S1/2(F=4)分别对应2.4480 KHzμm3及2.4538 KHzμm3.研究还发现随着F的增大,C3增大,z (原子与金属表面之间的距离)不变时,原子与理想金属表面间vdW作用增强.这一研究在实现原子囚禁及介质表面量子反射等方面有一定的意义.

  3. Enhancement of level-crossing resonances in rubidium atoms by frequency control of the exciting radiation field

    CERN Document Server

    Auzinsh, Marcis; Ferber, Ruvin; Gahbauer, Florian; Kalvans, Linards; Mozers, Arturs; Spiss, Agris

    2013-01-01

    We studied magneto-optical resonances caused by excited-state level crossings in a nonzero magnetic field. Experimental measurements were performed on the transitions of the $D_2$ line of rubidium. These measured signals were described by a theoretical model that takes into account all neighboring hyperfine transitions, the mixing of magnetic sublevels in an external magnetic field, the coherence properties of the exciting laser radiation, and the Doppler effect. Good agreement between the experimental measurements and the theoretical model could be achieved over a wide range of laser power densities. We further showed that the contrasts of the level-crossing peaks can be sensitive to changes in the frequency of the exciting laser radiation as small as several tens of megahertz when the hyperfine splitting of the exciting state is larger than the Doppler broadening.

  4. Measurement of hyperfine coupling constants of muoniated radicals in small molecule semiconductors

    Science.gov (United States)

    Schulz, L.; Wang, K.; Willis, M.; Nuccio, L.; Murahari, P.; Zhang, S.; Pratt, F. L.; Lord, J. S.; Morley, N. A.; Bernhard, C.; Drew, A. J.

    2014-12-01

    We report the hyperfine coupling constants of muoniated radicals formed in a number of organic semiconductors, via transverse field measurements taken in the Paschen Back limit, and compare the results to avoided level crossing resonances. Five muoniated radicals are found in tetracene, despite there only being three potential non-equivalent bonding sites, and we suggest that this might be down to crystal packing effects. For 6,13-bis(triisopropylsilylethynyl) pentacene and 6,13-bis(trimethlsilylethynyl)-pentacene, we demonstrate that the transverse field data supports the previously published avoided level crossing resonances.

  5. Measurement of hyperfine structure and isotope shift within the 7s1/2-7p1/2 transition in 203-Tl and 205-Tl

    CERN Document Server

    Ranjit, G; Vukasin, G D; Majumder, P K

    2013-01-01

    A two-step, two-color laser spectroscopy technique has been used to determine of the hyperfine splitting (HFS) of the 7p1/2 excited state in 203-Tl and 205-Tl, as well as the isotope shift within the 7s1/2 - 7p1/2 1301 nm transition. We find the hyperfine splittings in 203-Tl and 205-Tl to be 2152.2(7) MHz and 2173.3(8) MHz respectively. The 203-Tl - 205-Tl transition isotope shift is found to be 534.4(9) MHz. The HFS values each disagree by roughly 20 MHz from previously published values which quoted precision comparable to ours. In order to ensure accurate frequency-axis calibration in this new measurement, we employed both a Fabry-Perot cavity, as well as radio-frequency modulation to create sidebands in the absorption spectrum at well-defined frequency separation. In our experiment, one laser was locked to the ground-state 6p1/2 - 7s1/2 378 nm transition, while the second, spatially overlapping laser was scanned across the 7s1/2 (F=1) - 7p1/2 (F=0,1) hyperfine transitions.

  6. Hyperfine and Zeeman measurements in the infrared spectrum of doubly charged molecule D sup 3 sup 5 C1 sup 2 sup +

    CERN Document Server

    Cox, S G

    2001-01-01

    An experimental investigation of the X sup 3 SIGMA sup - ground electronic state of the doubly charged molecule D sup 3 sup 5 Cl sup 2 sup + was performed using the Fast-lon-Beam/Laser-Beam-Spectrometer (FIBLBS), with a CO sub 2 infrared laser acting as the source of exciting radiation. Hyperfine resolved transitions between the nu=1->2 vibrational bands were observed for D sup 3 sup 5 Cl sup 2 sup +. The observed spectrum was analysed for transition frequencies, linewidths and relative signal intensities. A solenoid was designed, built and incorporated into the FIBLBS for the inducement of Zeeman splitting in the hyperfine structure of D sup 3 sup 5 Cl sup 2 sup +. The solenoid was used to investigate the splitting of a P branch hyperfine quartet over a variety of magnetic fields and was subsequently assigned unambiguously as a P sub Q sub sub 2 sub sub 3 (6) transition, with F quantum numbers 7/2, 9/2, 11/2 and 13/2

  7. Calculation of the Van der Waals interaction coefficients C3 between excited state (|62 D3/2 F>) of 133 CS atoms and perfect surface of a metal in hyperfine atomic levels%超精细能级中133CS激发态(|62 D3/2F>)原子与理想金属表面间范德瓦尔斯作用系数C3的估算

    Institute of Scientific and Technical Information of China (English)

    魏奶萍; 赵小侠; 李莉; 张彦鹏; 李院院; 徐可为

    2016-01-01

    By utilizing alkali atoms and perfect surface of a metal between Van der Waals ( vdW) interaction and irreducible tensor method. We get analytical expression of coefficient C3 of hyperfine levels of alkali atoms. C3 values corresponding to hyperfine levels of 133Cs excited states (62D3/2(F=2,3,4,5)) are calculated. It is also shown that, the greater the F, the larger the C3 , and the stronger the vdW interaction when z does not change, where z is the distance of an atom from the metal surface. At the same time for C31 effect is produced by the elec-tric quadrupole moment because of no significant contribution, C3 numerical results did not meet with abnormal fluctuations.%利用碱金属原子与理想金属表面间范德瓦尔斯(vdW)作用势和不可约张量方法,导出超精细能级中碱金属原子特定量子态C3的解析表达式,完成133CS原子62D3/2(F=2,3,4,5)的C3数值计算,计算结果表明随着的增大,C3增大,z(原子与金属表面之间的距离)不变时,铯原子与理想金属表面间vdW作用增强.同时对于由电四极矩作用产生的C31效果因贡献不显著,C3数值结果并未见到有异常波动现象.

  8. Kinetic models in spin chemistry. 1. The hyperfine interaction

    DEFF Research Database (Denmark)

    Mojaza, M.; Pedersen, J. B.

    2012-01-01

    Kinetic models for quantum systems are quite popular due to their simplicity, although they are difficult to justify. We show that the transformation from quantum to kinetic description can be done exactly for the hyperfine interaction of one nuclei with arbitrary spin; more spins are described w...

  9. Control of inhomogeneous atomic ensembles of hyperfine qudits

    DEFF Research Database (Denmark)

    Mischuck, Brian Edward; Merkel, Seth T.; Deutsch, Ivan H.

    2012-01-01

    We study the ability to control d-dimensional quantum systems (qudits) encoded in the hyperfine spin of alkali-metal atoms through the application of radio- and microwave-frequency magnetic fields in the presence of inhomogeneities in amplitude and detuning. Such a capability is essential...

  10. Effect of nanocrystallization on the electrical conductivity enhancement and Moessbauer hyperfine parameters of iron based glasses

    Energy Technology Data Exchange (ETDEWEB)

    El-Desoky, M.M., E-mail: mmdesoky@gmail.com [Department of Physics, Faculty of Education, Suez Canal University, Al-Arish 45511, North Sinaa (Egypt); Ibrahim, F.A. [Department of Physics, Faculty of Education, Suez Canal University, Al-Arish 45511, North Sinaa (Egypt); Mostafa, A.G.; Hassaan, M.Y. [Department of Physics, Faculty of Science, Al-Azhar University, Nasr City 11884, Cairo (Egypt)

    2010-09-15

    Selected glasses of Fe{sub 2}O{sub 3}-PbO{sub 2}-Bi{sub 2}O{sub 3} system have been transformed into nanomaterials by annealing at temperature close to crystallization temperature (T{sub c}) for 1 h. The effects of the annealing of the present samples on its structural and electrical properties were studied by Moessbauer spectroscopy, transmission electron micrograph (TEM), differential scanning calorimeter (DSC) and dc conductivity ({sigma}). Moessbauer spectroscopy was used in order to determine the states of iron and its hyperfine structure. The effect of nanocrystalization on the Moessbauer hyperfine parameters did not exhibit significant modifications in present glasses. However, in case of glass ceramic nanocrystals show a distinct decrease in the quadrupole splitting ({Delta}) is observed, reflecting an evident decrease in the distortion of structural units like FeO{sub 4} units. In general, the Moessbauer parameters of the nano-crystalline phase exhibit tendency to increase with PbO{sub 2} content. TEM of as-quenched glasses confirm the homogeneous and essentially featureless morphology. TEM of the corresponding glass ceramic nanocrystals indicates nanocrystals embedded in the glassy matrix with average particle size of about 32 nm. The crystallization temperature (T{sub c}) was observed to decrease with PbO{sub 2} content. The glass ceramic nanocrystals obtained by annealing at T{sub c} exhibit improvement of electrical conductivity up to four orders of magnitude than the starting glasses. This considerable improvement of electrical conductivity after nanocrystallization is attributed to formation of defective, well-conducting phases 'easy conduction paths' along the glass-crystallites interfaces.

  11. Positronium energy levels at order $m \\alpha^7$: light-by-light scattering in the two-photon-annihilation channel

    CERN Document Server

    Adkins, Gregory S; Salinger, M D; Wang, Ruihan; Fell, Richard N

    2014-01-01

    Recent and ongoing experimental work on the positronium spectrum motivates new efforts to calculate positronium energy levels at the level of three loop corrections. We have obtained results for one set of such corrections involving light-by-light scattering of the photons produced in a two-photon virtual annihilation process. Our result is an energy shift $1.58377(8) m \\alpha^7/\\pi^3$ for the n=1 singlet state, correcting the ground state hyperfine splitting by -6.95 kHz. We also obtained a new and more precise result for the light-by-light scattering correction to the real decay of parapositronium into two photons.

  12. Observation of hyperfine mixing in measurements of a magnetic octupole decay in isotopically pure nickel-like 129Xe and 132Xe ions

    Energy Technology Data Exchange (ETDEWEB)

    Trabert, E; Beiersdorfer, P; Brown, G V

    2006-12-21

    We present measurements of high statistical significance of the rate of the magnetic octupole (M3) decay in nickel-like ions of isotopically pure {sup 129}Xe and {sup 132}Xe. On {sup 132}Xe, an isotope with zero nuclear spin and therefore without hyperfine structure, the lifetime of the metastable level was established as (15.06 {+-} 0.24) ms. On {sup 129}Xe, an additional fast (2.7 {+-} 0.1 ms) decay component was established that represents hyperfine mixing with a level that decays by electric quadrupole (E2) radiation.

  13. Theoretical calculations of hyperfine coupling constants for muoniated butyl radicals.

    Science.gov (United States)

    Chen, Ya Kun; Fleming, Donald G; Wang, Yan Alexander

    2011-04-01

    The hyperfine coupling constants (HFCCs) of all the butyl radicals that can be produced by muonium (Mu) addition to butene isomers (1- and 2-butene and isobutene) have been calculated, to compare with the experimental results for the muon and proton HFFCs for these radicals reported in paper II (Fleming, D. G.; et al. J. Phys. Chem. A 2011, 10.1021/jp109676b) that follows. The equilibrium geometries and HFCCs of these muoniated butyl radicals as well as their unsubstituted isotopomers were treated at both the spin-unrestricted MP2/EPR-III and B3LYP/EPR-III levels of theory. Comparisons with calculations carried out for the EPR-II basis set have also been made. All calculations were carried out in vacuo at 0 K only. A C-Mu bond elongation scheme that lengthens the equilibrium C-H bond by a factor of 1.076, on the basis of recent quantum calculations of the muon HFCCs of the ethyl radical, has been exploited to determine the vibrationally corrected muon HFCCs. The sensitivity of the results to small variations around this scale factor was also investigated. The computational methodology employed was "benchmarked" in comparisons with the ethyl radical, both with higher level calculations and with experiment. For the β-HFCCs of interest, compared to B3LYP, the MP2 calculations agree better with higher level theories and with experiment in the case of the eclipsed C-Mu bond and are generally deemed to be more reliable in predicting the equilibrium conformations and muon HFCCs near 0 K, in the absence of environmental effects. In some cases though, the experimental results in paper II demonstrate that environmental effects enhance the muon HFCC in the solid phase, where much better agreement with the experimental muon HFCCs near 0 K is found from B3LYP than from MP2. This seemingly better level of agreement is probably fortuitous, due to error cancellations in the DFT calculations, which appear to mimic these environmental effects. For the staggered proton HFCCs of the

  14. Hyperfine structures and Landé g{sub J}-factors for n=2 states in beryllium-, boron-, carbon-, and nitrogen-like ions from relativistic configuration interaction calculations

    Energy Technology Data Exchange (ETDEWEB)

    Verdebout, S.; Nazé, C. [Chimie Quantique et Photophysique, CP160/09, Université Libre de Bruxelles, B 1050 Brussels (Belgium); Jönsson, P., E-mail: per.jonsson@mah.se [Faculty of Technology and Society, Group for Materials Science and Applied Mathematics, Malmö University, 205-06 Malmö (Sweden); Rynkun, P. [Institute of Theoretical Physics and Astronomy, Vilnius University, LT-01108 Vilnius (Lithuania); Godefroid, M. [Chimie Quantique et Photophysique, CP160/09, Université Libre de Bruxelles, B 1050 Brussels (Belgium); Gaigalas, G. [Institute of Theoretical Physics and Astronomy, Vilnius University, LT-01108 Vilnius (Lithuania)

    2014-09-15

    Energy levels, hyperfine interaction constants, and Landé g{sub J}-factors are reported for n=2 states in beryllium-, boron-, carbon-, and nitrogen-like ions from relativistic configuration interaction calculations. Valence, core–valence, and core–core correlation effects are taken into account through single and double-excitations from multireference expansions to increasing sets of active orbitals. A systematic comparison of the calculated hyperfine interaction constants is made with values from the available literature.

  15. Hyperfine relaxation of an optically pumped cesium vapor

    Energy Technology Data Exchange (ETDEWEB)

    Tornos, J.; Amare, J.C.

    1986-07-01

    The relaxation of hyperfine orientation indirectly induced by optical pumping with a sigma-polarized D/sub 1/-light in a cesium vapor in the presence of Ar is experimentally studied. The detection technique ensures the absence of quadrupole relaxation contributions in the relaxation signals. The results from the dependences of the hyperfine relaxation rate on the temperature and argon pressure are: diffusion coefficient of Cs in Ar, D/sub 0/ = 0.101 +- 0.010 cm/sup 2/s/sup -1/ at 0/sup 0/C and 760 Torr; relaxation cross section by Cs-Ar collisions, sigma/sub c/ = (104 +- 5) x 10/sup -23/ cm/sup 2/; relaxation cross section by Cs-Cs (spin exchange) collisions, sigma/sub e//sub x/ = (1.63 +- 0.13) x 10/sup -14/ cm/sup 2/.

  16. Tuning hyperfine fields in conjugated polymers for coherent organic spintronics.

    Science.gov (United States)

    Lee, Sang-Yun; Paik, Seo-Young; McCamey, Dane R; Yu, Justin; Burn, Paul L; Lupton, John M; Boehme, Christoph

    2011-02-23

    An appealing avenue for organic spintronics lies in direct coherent control of the spin population by means of pulsed electron spin resonance techniques. Whereas previous work has focused on the electrical detection of coherent spin dynamics, we demonstrate here the equivalence of an all-optical approach, allowing us to explore the influence of materials chemistry on the spin dynamics. We show that deuteration of the conjugated polymer side groups weakens the local hyperfine fields experienced by electron-hole pairs, thereby lowering the threshold for the resonant radiation intensity at which coherent coupling and spin beating occur. The technique is exquisitively sensitive to previously obscured material properties and offers a route to quantifying and tuning hyperfine fields in organic semiconductors.

  17. Experimental and ab initio study of the hyperfine parameters of ZnFe {sub 2}O{sub 4} with defects

    Energy Technology Data Exchange (ETDEWEB)

    Quintero, J. Melo; Salcedo Rodríguez, K. L.; Pasquevich, G. A.; Zélis, P. Mendoza; Stewart, S. J., E-mail: stewart@fisica.unlp.edu.ar; Rodríguez Torres, C. E.; Errico, L. A. [Universidad Nacional de La Plata, IFLP-CCT- La Plata-CONICET and Departamento de Física, Facultad de Ciencias Exactas, C. C. 67 (Argentina)

    2016-12-15

    We present a combined Mössbauer and ab initio study on the influence of oxygen-vacancies on the hyperfine and magnetic properties of the ZnFe {sub 2}O{sub 4} spinel ferrite. Samples with different degree of oxygen-vacancies were obtained from zinc ferrite powder that was thermally treated at different temperatures up to 650 {sup ∘}C under vacuum.Theoretical calculations of the hyperfine parameters, magnetic moments and magnetic alignment have been carried out considering different defects such as oxygen vacancies and cation inversion. We show how theoretical and experimental approaches are complementary to characterize the local structure around Fe atoms and interpret the observed changes in the hyperfine parameters as the level of defects increases.

  18. Nuclear Quadrupole Hyperfine Structure in HC14N/H14NC and DC15N/D15NC Isomerization: A Diagnostic Tool for Characterizing Vibrational Localization

    CERN Document Server

    Wong, Bryan M

    2010-01-01

    Large-amplitude molecular motions which occur during isomerization can cause significant changes in electronic structure. These variations in electronic properties can be used to identify vibrationally-excited eigenstates which are localized along the potential energy surface. This work demonstrates that nuclear quadrupole hyperfine interactions can be used as a diagnostic marker of progress along the isomerization path in both the HC14N/H14NC and DC15N/D15NC chemical systems. Ab initio calculations at the CCSD(T)/cc-pCVQZ level indicate that the hyperfine interaction is extremely sensitive to the chemical bonding of the quadrupolar 14N nucleus and can therefore be used to determine in which potential well the vibrational wavefunction is localized. A natural bonding orbital analysis along the isomerization path further demonstrates that hyperfine interactions arise from the asphericity of the electron density at the quadrupolar nucleus. Using the CCSD(T) potential surface, the quadrupole coupling constants of...

  19. Hyperfine interactions and electronic structures of BaFe{sub 2}As{sub 2}: a first-principles LDA+U study

    Energy Technology Data Exchange (ETDEWEB)

    Pang Hua, E-mail: hpang@lzu.edu.cn; Fang Yang; Li Fashen [Lanzhou UniversityLanzhou, Key Laboratory for Magnetism and Magnetic Materials of the Ministry of Education, Department of Physics (China)

    2011-07-15

    The hyperfine parameters of hyperfine fields, electric field gradients and isomer shifts at the Fe site are investigated based on the first-principles calculations of the electronic structures using LDA (GGA)+U method in the low-temperature orthorhombic antiferromagnetic phase of undoped BaFe{sub 2}As{sub 2}. It is fond that the electric field gradient of Fe nucleus is highly related with the electronic structures close to the Fermi level. Though the addition of negative on-site Coulomb interaction to Fe-3d states improves the calculated magnetic moment of Fe atom and the hyperfine parameters of Fe nucleus when U = -0.1 Ry (-0.08 Ry) for GGA+U (LDA+U) method, a negative U correction does not capture the right physics of this system. The calculations prove the strong coupling between the magnetic, structural and electronic properties in antiferromagnetic BaFe{sub 2}As{sub 2} parent.

  20. Hadronic deuteron polarizability contribution the hyperfine structure in muonic deuterium

    Directory of Open Access Journals (Sweden)

    Eskin A.V.

    2017-01-01

    Full Text Available The calculation of the contribution to the polarizability of the nucleus to hyperfine structure of muonic hydrogen is carried out within the unitary isobar model and on the basis of experimental data on the structure functions of deep inelastic lepton-proton and lepton-deuteron scattering. The calculation of virtual absorption cross sections of transversely and longitudinally polarized photons by nucleons in the resonance region is performed in the framework of the program MAID.

  1. Ligand field splittings in core level transitions for transition metal (TM) oxides: Tanabe-Sugano diagrams and (TM) dangling bonds in vacated O-atom defects

    Science.gov (United States)

    Lucovsky, Gerry; Wu, Kun; Pappas, Brian; Whitten, Jerry

    2013-04-01

    Defect states in the forbidden band-gap below the conduction band edge are active as electron traps in nano-grain high-) transition metal (TM) oxides with thickness >0.3 nm, e.g., ZrO2 and HfO2. These oxides have received considerable attention as gate-dielectrics in complementary metal oxide semiconductor (CMOS) devices, and more recently are emerging as candidates for charge storage and memory devices. To provide a theoretical basis for device functionality, ab-initio many-electron theory is combined with X-ray absorption spectroscopy (XAS) to study O K edge and TM core level transitions. These studies identify ligand field splittings (ΔLF) for defect state features,. When compared with those obtained from O-atom and TM-atom core spectroscopic transitions, this provides direct information about defect state sun-nm bonding arrangements. comparisons are made for (i) elemental TiO2 and Ti2O3 with different formal ionic charges, Ti4+ and Ti3+ and for (ii) Magneli Phase alloys, TinO2n-1, n is an integer 9>=n>3, and (TiO2)x(HfO2)1-x alloys. The alloys display multi-valent behavior from (i) different ionic-charge states, (ii} local bond-strain, and (iii) metallic hopping transport. The intrinsic bonding defects in TM oxides are identified as pairs of singly occupied dangling bonds. For 6-fold coordinated Ti-oxides defect excited states in 2nd derivative O K pre-edge spectra are essentially the same as single Ti-atom d2 transitions in Tanabe-Sugano (T-S) diagrams. O-vacated site defects in 8-fold coordinated ZrO2 and HfO2 are described by d8 T-S diagrams. T-S defect state ordering and splittings are functions of the coordination and symmetry of vacated site bordering TM atoms. ΔLF values from the analysis of T-S diagrams indicate medium range order (MRO) extending to 3rd and 4th nearest-neighbor (NN) TM-atoms. Values are different for 6-fold Ti, and 8-fold ZrO2 and HfO2, and scale inversely with differences in respective formal ionic radii. O-vacated site bonding

  2. The hyperfine properties of iron-gallium alloys

    Energy Technology Data Exchange (ETDEWEB)

    Elzain, M., E-mail: elzain@squ.edu.om; Gismelseed, A.; Al-Rawas, A.; Yousif, A.; Widatallah, H.; Al-Azri, Maya [Sultan Qaboos University, Department of Physics (Oman); Al-Barwani, M. [NYU Abu Dhabi (United Arab Emirates)

    2016-12-15

    The hyperfine properties at Fe site in iron-gallium alloy are calculated using the full-potential linear-augmented-plane-waves method. We have calculated the Fermi contact field (B{sub hf}) and isomer shift (δ) at the Fe site versus the number of neighbouring Ga atoms. We found that B{sub hf} decrease whereas δ increases with increasing number of neighbouring G atom. In addition we have calculated the hyperfine properties of FeGa system with DO{sub 3} structure, where various distributions of 4 the Ga atoms in the conventional unit cell are considered (including the regular DO{sub 3} structure). We found that the DO{sub 3} structure has the lowest energy as compared to the other configurations. The two distinct A and D sites of the ordered DO{sub 3} conventional unit cell have two distinct values for B{sub hf} and δ. On changing the atomic arrangement of the Ga atoms within the conventional unit cell, the configuration of the A site is maintained whereas that of the D site becomes imperfect. The contact magnetic hyperfine fields of the D-like sites in the imperfect structures are lower than that of the DO{sub 3}D site.

  3. The hyperfine properties of iron-gallium alloys

    Science.gov (United States)

    Elzain, M.; Gismelseed, A.; Al-Rawas, A.; Yousif, A.; Widatallah, H.; Al-Azri, Maya; Al-Barwani, M.

    2016-12-01

    The hyperfine properties at Fe site in iron-gallium alloy are calculated using the full-potential linear-augmented-plane-waves method. We have calculated the Fermi contact field (Bhf) and isomer shift ( δ) at the Fe site versus the number of neighbouring Ga atoms. We found that Bhf decrease whereas δ increases with increasing number of neighbouring G atom. In addition we have calculated the hyperfine properties of FeGa system with DO3 structure, where various distributions of 4 the Ga atoms in the conventional unit cell are considered (including the regular DO3 structure). We found that the DO3 structure has the lowest energy as compared to the other configurations. The two distinct A and D sites of the ordered DO3 conventional unit cell have two distinct values for Bhf and δ. On changing the atomic arrangement of the Ga atoms within the conventional unit cell, the configuration of the A site is maintained whereas that of the D site becomes imperfect. The contact magnetic hyperfine fields of the D-like sites in the imperfect structures are lower than that of the DO3D site.

  4. The effect of oxygen vacancies on the hyperfine properties of metal-doped SnO2

    Science.gov (United States)

    Aragón, F. H.; Villegas-Lelovsky, L.; Martins, J. B. L.; Coaquira, J. A. H.; Cohen, R.; Nagamine, L. C. C. M.; Morais, P. C.

    2017-03-01

    We have performed a Mössbauer investigation of oxygen-vacancy formation on a doped substitutional solution of Sn1‑y M y O2 (M  =  Al, Fe, Ce and Er) nanoparticles. Experimental results were assessed from Mössbauer spectroscopy data, which suggest the rise of the oxygen-vacancy population while increasing the content of dopant ions (M). Likewise, we have analyzed the dependence of the structural, electronic and hyperfine properties on the oxygen-vacancy concentration through first-principles calculations of the SnO2‑x (where x varies from 0 to 0.25) system. The results obtained from the isomer shift and quadrupole splitting indicate a significant dependence of the hyperfine properties on the number of oxygen vacancies. Moreover, after structural optimization of the Sn16O32-Vo supercell (where Vo is the number of oxygen vacancies) we found an increase of the unit-cell volume with the increase of Vo, while the bulk modulus showed a linear decrease with Vo. Indeed, our results corroborate the experimental findings for pure and transition-metal-doped SnO2 systems for which the presence of the oxygen vacancy plays a key role.

  5. Steady-state nevirapine, lamivudine and stavudine levels in Malawian HIV-infected children on antiretroviral therapy using split Triomune 30 tablets.

    NARCIS (Netherlands)

    Poerksen, G.; Pollock, L.; Moons, P.; Chesshyre, E.; Burger, D.M.; Khoo, S.; Molyneux, E.

    2010-01-01

    BACKGROUND: Children remain under-represented in national antiretroviral treatment (ART) programmes in settings with limited resources and high HIV prevalence. In Malawi, an increasing number of HIV-infected children have been started on ART with split tablets of an adult fixed-dose combination drug

  6. Fine- and hyperfine-structure effects in molecular photoionization: II. Resonance-enhanced multiphoton ionization and hyperfine-selective generation of molecular cations

    CERN Document Server

    Germann, Matthias

    2016-01-01

    Resonance-enhanced multiphoton ionization (REMPI) is a widely used technique for studying molecular photoionization and producing molecular cations for spectroscopy and dynamics studies. Here, we present a model for describing hyperfine-structure effects in the REMPI process and for predicting hyperfine populations in molecular ions produced by this method. This model is a generalization of our model for fine- and hyperfine- structure effects in one-photon ionization of molecules presented in the preceding companion article. This generalization is achieved by covering two main aspects: (1) treatment of the neutral bound-bound transition including hyperfine structure that makes up the first step of the REMPI process and (2) modification of our ionization model to account for anisotropic populations resulting from this first excitation step. Our findings may be used for analyzing results from experiments with molecular ions produced by REMPI and may serve as a theoretical background for hyperfine-selective ioni...

  7. The effect of spin polarization on zero field splitting parameters in paramagnetic pi-electron molecules.

    Science.gov (United States)

    van Gastel, Maurice

    2009-09-28

    Spin polarization effects play an important role in the theory of isotropic hyperfine interactions for aromatic protons. The spin polarization gives rise to significant isotropic proton hyperfine interactions--spin-dependent one-electron properties--smaller than 0 MHz and the effect has been theoretically described [H. M. McConnell and D. B. J. Chesnut, Chem. Phys. 28, 107 (1958)]. The influence of spin polarization on the zero field splitting parameters, which are spin-dependent two-electron properties, has not been clearly identified yet. A phenomenological equation is proposed here for the contribution of spin polarization to the zero field splitting parameter D in analogy to McConnell's equation for hyperfine interactions. The presence of the effect is demonstrated in a series of calculations on polyacenes in the triplet state and turns out to be responsible for up to 50% of the D parameter in the case of naphthalene! It is found that spin-unrestricted single-determinant methods, including the widely used density functional theory methods, do not accurately reproduce the two-electron reduced electron density required for the evaluation of two-electron spin-dependent properties. For the accurate calculation of zero field splitting parameters by quantum chemical methods, it thus seems necessary to resort to correlated ab initio methods which do not give rise to spin contamination and which do provide an accurate description of the two-electron reduced electron density.

  8. Split liver transplantation.

    Science.gov (United States)

    Yersiz, H; Cameron, A M; Carmody, I; Zimmerman, M A; Kelly, B S; Ghobrial, R M; Farmer, D G; Busuttil, R W

    2006-03-01

    Seventy-five thousand Americans develop organ failure each year. Fifteen percent of those on the list for transplantation die while waiting. Several possible mechanisms to expand the organ pool are being pursued including the use of extended criteria donors, living donation, and split deceased donor transplants. Cadaveric organ splitting results from improved understanding of the surgical anatomy of the liver derived from Couinaud. Early efforts focused on reduced-liver transplantation (RLT) reported by both Bismuth and Broelsch in the mid-1980s. These techniques were soon modified to create both a left lateral segment graft appropriate for a pediatric recipient and a right trisegment for an appropriately sized adult. Techniques of split liver transplantation (SLT) were also modified to create living donor liver transplantation. Pichlmayr and Bismuth reported successful split liver transplantation in 1989 and Emond reported a larger series of nine split procedures in 1990. Broelsch and Busuttil described a technical modification in which the split was performed in situ at the donor institution with surgical division completed in the heart beating cadaveric donor. In situ splitting reduces cold ischemia, simplifies identification of biliary and vascular structures, and reduces reperfusion hemorrhage. However, in situ splits require specialized skills, prolonged operating room time, and increased logistical coordination at the donor institution. At UCLA over 120 in situ splits have been performed and this technique is the default when an optimal donor is available. Split liver transplantation now accounts for 10% of adult transplantations at UCLA and 40% of pediatric transplantations.

  9. Hyperfine structure and nuclear hyperpolarization observed in the bound exciton luminescence of Bi donors in natural Si.

    Science.gov (United States)

    Sekiguchi, T; Steger, M; Saeedi, K; Thewalt, M L W; Riemann, H; Abrosimov, N V; Nötzel, N

    2010-04-02

    As the deepest group-V donor in Si, Bi has by far the largest hyperfine interaction and also a large I = 9/2 nuclear spin. At zero field this splits the donor ground state into states having total spin 5 and 4, which are fully resolved in the photoluminescence spectrum of Bi donor bound excitons. Under a magnetic field, the 60 expected allowed transitions cannot be individually resolved, but the effects of the nuclear spin distribution, -9/2 < or = I(z) < or = 9/2, are clearly observed. A strong hyperpolarization of the nuclear spin towards I(z) = -9/2 is observed to result from the nonresonant optical excitation. This is very similar to the recently reported optical hyperpolarization of P donors observed by EPR at higher magnetic fields. We introduce a new model to explain this effect, and predict that it may be very fast.

  10. Quadrupole splitting and isomer shifts in Te oxides investigated using nuclear forward scattering

    Science.gov (United States)

    Klobes, Benedikt; Barrier, Nicolas; Vertruyen, Benedicte; Martin, Christine; Hermann, Raphaël P.

    2014-04-01

    Nuclear forward scattering by 125Te is a viable alternative to conventional 125Te Mössbauer spectroscopy avoiding all source related issues. Using reference compounds with known hyperfine parameters and Te oxides exhibiting stereochemically active lone pairs, we show that nuclear forward scattering by 125Te can be reliably used to extract quadrupole splitting energy and relative isomer shift. The rough correlation between Te-Ocoordination and quadrupole splitting energy as put forward by Takeda and Greenwood (J. Chem. Soc. Dalton, 2207, 1975), is corroborated by the presented results.

  11. Polarizabilities and tune-out wavelengths of the hyperfine ground states of $^{87,85}$Rb

    CERN Document Server

    Wang, Xia; Xie, Lu-You; Zhang, Deng-Hong; Dong, Chen-Zhong

    2016-01-01

    The static and dynamic polarizabilities, and the tune-out wavelengths of the ground state of Rb and the hyperfine ground states of $^{87, 85}$Rb have been calculated by using relativistic configuration interaction plus core polarization(RCICP) approach. It is found that the first primary tune-out wavelengths of the $ 5s_{1/2}, F=1, 2 $ states of $ ^{87}$Rb are 790.018187(193) nm and 790.032602(193) nm severally, where the calculated result for the $ 5s_{1/2}, F=2 $ state is in good agreement with the latest high-precision measurement 790.032388(32) nm [Phys. Rev. A 92, 052501 (2015)]. Similarly, the first primary tune-out wavelengths of the $ 5s_{1/2}, F=2, 3 $ states of $^{85}$Rb are 790.023515(218) nm and 790.029918(218) nm respectively. Furthermore, the tune-out wavelengths for the different magnetic sublevels $ M_{F}$ of each hyperfine level $F$ are also determined by considering the contributions of tensor polarizabilities.

  12. Electron plasmas as a diagnostic tool for hyperfine spectroscopy of antihydrogen

    Science.gov (United States)

    Friesen, T.; Amole, C.; Ashkezari, M. D.; Baquero-Ruiz, M.; Bertsche, W.; Bowe, P. D.; Butler, E.; Capra, A.; Cesar, C. L.; Charlton, M.; Deller, A.; Evetts, N.; Eriksson, S.; Fajans, J.; Fujiwara, M. C.; Gill, D. R.; Gutierrez, A.; Hangst, J. S.; Hardy, W. N.; Hayden, M. E.; Isaac, C. A.; Jonsell, S.; Kurchaninov, L.; Little, A.; Madsen, N.; McKenna, J. T. K.; Menary, S.; Napoli, S. C.; Olchanski, K.; Olin, A.; Pusa, P.; Rasmussen, C. Ø.; Robicheaux, F.; Sarid, E.; Silveira, D. M.; So, C.; Stracka, S.; Thompson, R. I.; van der Werf, D. P.; Wurtele, J. S.

    2013-03-01

    Long term magnetic confinement of antihydrogen atoms has recently been demonstrated by the ALPHA collaboration at CERN, opening the door to a range of experimental possibilities. Of particular interest is a measurement of the antihydrogen spectrum. A precise comparison of the spectrum of antihydrogen with that of hydrogen would be an excellent test of CPT symmetry. One prime candidate for precision CPT tests is the ground-state hyperfine transition; measured in hydrogen to a precision of nearly one part in 1012. Effective execution of such an experiment with trapped antihydrogen requires precise knowledge of the magnetic environment. Here we present a solution that uses an electron plasma confined in the antihydrogen trapping region. The cyclotron resonance of the electron plasma is probed with microwaves at the cyclotron frequency and the subsequent heating of the electron plasma is measured through the plasma quadrupole mode frequency. Using this method, the minimum magnetic field of the neutral trap can be determined to within 4 parts in 104. This technique was used extensively in the recent demonstration of resonant interaction with the hyperfine levels of trapped antihydrogen atoms.

  13. Electron-impact rotational and hyperfine excitation of HCN, HNC, DCN and DNC

    CERN Document Server

    Faure, A; Stoecklin, T; Tennyson, J

    2007-01-01

    Rotational excitation of isotopologues of HCN and HNC by thermal electron-impact is studied using the molecular {\\bf R}-matrix method combined with the adiabatic-nuclei-rotation (ANR) approximation. Rate coefficients are obtained for electron temperatures in the range 5$-$6000 K and for transitions among all levels up to J=8. Hyperfine rates are also derived using the infinite-order-sudden (IOS) scaling method. It is shown that the dominant rotational transitions are dipole allowed, that is those for which $\\Delta J=1$. The hyperfine propensity rule $\\Delta J=\\Delta F$ is found to be stronger than in the case of He$-$HCN collisions. For dipole allowed transitions, electron-impact rates are shown to exceed those for excitation of HCN by He atoms by 6 orders of magnitude. As a result, the present rates should be included in any detailed population model of isotopologues of HCN and HNC in sources where the electron fraction is larger than 10$^{-6}$, for example in interstellar shocks and comets.

  14. Electron-impact rotational and hyperfine excitation of HCN, HNC, DCN and DNC

    Science.gov (United States)

    Faure, Alexandre; Varambhia, Hemal N.; Stoecklin, Thierry; Tennyson, Jonathan

    2007-12-01

    Rotational excitation of isotopologues of HCN and HNC by thermal electron-impact is studied using the molecular R-matrix method combined with the adiabatic-nuclei-rotation approximation. Rate coefficients are obtained for electron temperatures in the range 5-6000 K and for transitions among all levels up to J = 8. Hyperfine rates are also derived using the infinite-order-sudden scaling method. It is shown that the dominant rotational transitions are dipole-allowed, that is, those for which ΔJ = 1. The hyperfine propensity rule ΔJ = ΔF is found to be stronger than that in the case of He-HCN collisions. For dipole-allowed transitions, electron-impact rates are shown to exceed those for excitation of HCN by He atoms by six orders of magnitude. As a result, the present rates should be included in any detailed population model of isotopologues of HCN and HNC in sources where the electron fraction is larger than 10-6, for example, in interstellar shocks and comets.

  15. Electron plasmas as a diagnostic tool for hyperfine spectroscopy of antihydrogen

    Energy Technology Data Exchange (ETDEWEB)

    Friesen, T.; Thompson, R. I. [Department of Physics and Astronomy, University of Calgary, Calgary AB, T2N 1N4 (Canada); Amole, C.; Capra, A.; Menary, S. [Department of Physics and Astronomy, York University, Toronto ON, M3J 1P3 (Canada); Ashkezari, M. D.; Hayden, M. E. [Department of Physics, Simon Fraser University, Burnaby BC, V5A 1S6 (Canada); Baquero-Ruiz, M.; Fajans, J.; Little, A.; So, C.; Wurtele, J. S. [Department of Physics, University of California, Berkeley, CA 94720-7300 (United States); Bertsche, W. [School of Physics and Astronomy, University of Manchester, M13 9PL Manchester, UK and The Cockcroft Institute, WA4 4AD Warrington (United Kingdom); Bowe, P. D.; Hangst, J. S.; Rasmussen, C. O. [Department of Physics and Astronomy, Aarhus University, DK-8000 Aarhus C (Denmark); Butler, E. [Physics Department, CERN, CH-1211 Geneva 23 (Switzerland); Cesar, C. L.; Silveira, D. M. [Instituto de Fisica, Universidade Federal do Rio de Janeiro, Rio de Janeiro 21941-972 (Brazil); Charlton, M. [Department of Physics, College of Science, Swansea University, Swansea SA2 8PP (United Kingdom); and others

    2013-03-19

    Long term magnetic confinement of antihydrogen atoms has recently been demonstrated by the ALPHA collaboration at CERN, opening the door to a range of experimental possibilities. Of particular interest is a measurement of the antihydrogen spectrum. A precise comparison of the spectrum of antihydrogen with that of hydrogen would be an excellent test of CPT symmetry. One prime candidate for precision CPT tests is the ground-state hyperfine transition; measured in hydrogen to a precision of nearly one part in 10{sup 12}. Effective execution of such an experiment with trapped antihydrogen requires precise knowledge of the magnetic environment. Here we present a solution that uses an electron plasma confined in the antihydrogen trapping region. The cyclotron resonance of the electron plasma is probed with microwaves at the cyclotron frequency and the subsequent heating of the electron plasma is measured through the plasma quadrupole mode frequency. Using this method, the minimum magnetic field of the neutral trap can be determined to within 4 parts in 10{sup 4}. This technique was used extensively in the recent demonstration of resonant interaction with the hyperfine levels of trapped antihydrogen atoms.

  16. The theory of the Bohr-Weisskopf effect in the hyperfine structure

    CERN Document Server

    Karpeshin, F F

    2015-01-01

    For twenty years research into the anomalies in the HF spectra was going in a wrong direction by fighting the related Bohr-Weisskopf effect. As a way out, the model-independent way is proposed of estimating the nuclear radii from the hyper-fine splitting. The way is based on analogy of HFS to internal conversion coefficients, and the Bohr-Weisskopf effect - to the anomalies in the internal conversion coefficients. This makes transparent It is shown that the parameters which can be extracted from the data are the even nuclear moments of the magnetization distribution. The radii $R_2$ and (for the first time) $R_4$ are thus obtained by analysis of the experimental HFS for the H- and Li-like ions of $^{209}$Bi. The critical prediction of the HFS for the $2p_{1/2}$ state is discussed. The moments may be determined in this way only if the higher QED effects are properly taken into account. Therefore, this set of the parameters form a basis of a strict QED test. Experimental prospects are discussed, aimed at retrie...

  17. PRISM: pair-read informed split-read mapping for base-pair level detection of insertion, deletion and structural variants.

    Science.gov (United States)

    Jiang, Yue; Wang, Yadong; Brudno, Michael

    2012-10-15

    The development of high-throughput sequencing technologies has enabled novel methods for detecting structural variants (SVs). Current methods are typically based on depth of coverage or pair-end mapping clusters. However, most of these only report an approximate location for each SV, rather than exact breakpoints. We have developed pair-read informed split mapping (PRISM), a method that identifies SVs and their precise breakpoints from whole-genome resequencing data. PRISM uses a split-alignment approach informed by the mapping of paired-end reads, hence enabling breakpoint identification of multiple SV types, including arbitrary-sized inversions, deletions and tandem duplications. Comparisons to previous datasets and simulation experiments illustrate PRISM's high sensitivity, while PCR validations of PRISM results, including previously uncharacterized variants, indicate an overall precision of ~90%. PRISM is freely available at http://compbio.cs.toronto.edu/prism.

  18. Combined effect of coherent Z exchange and the hyperfine interaction in the atomic parity-nonconserving interaction

    Science.gov (United States)

    Johnson, W. R.; Safronova, M. S.; Safronova, U. I.

    2003-06-01

    The nuclear spin-dependent parity-nonconserving (PNC) interaction arising from a combination of the hyperfine interaction and the coherent, spin-independent, PNC interaction from Z exchange is evaluated using many-body perturbation theory. For the 6s1/2-7s1/2 transition in 133Cs, we obtain a result that is about 40% smaller than that found previously by Bouchiat and Piketty [Phys. Lett. B 269, 195 (1991)]. Applying this result to 133Cs leads to an increase in the experimental value of nuclear anapole moment and exacerbates differences between constraints on PNC meson coupling constants obtained from the Cs anapole moment and those obtained from other nuclear parity violating experiments. Nuclear spin-dependent PNC dipole matrix elements, including contributions from the combined weak-hyperfine interaction, are also given for the 7s1/2-8s1/2 transition in 211Fr and for transitions between ground-state hyperfine levels in K, Rb, Cs, Ba+, Au, Tl, Fr, and Ra+.

  19. Anisotropic hyperfine interactions and spin relaxation in neptunyl salts

    Energy Technology Data Exchange (ETDEWEB)

    Asch, L.; Dunlap, B.D.; Marquardt, R.; Potzel, W.; Litterst, F.J.; Werner, G.D.; Weigel, F.; Spirlet, J.C.; Kalvius, G.M.

    1987-09-01

    Moessbauer spectra of hexavalent neptunyls X/sub 2/(NpO/sub 2/)Cl/sub 4/ and X/sub 4/(NpO/sub 2/)(CO/sub 3/)/sub 3/ with X = Na, K, Cs, (NH/sub 4/) and ((C/sub 2/H/sub 5/)/sub 4/N) are discussed and compared to EPR data. In cases where reliable values of hyperfine parameters can be extracted, the Moessbauer spectra give fine details of bonding structure. It is found that the O-Np-O bond is not linear and that exchanging the cation results in small but definite changes. 9 refs., 5 figs.

  20. Modeling flux noise in SQUIDs due to hyperfine interactions.

    Science.gov (United States)

    Wu, Jiansheng; Yu, Clare C

    2012-06-15

    Recent experiments implicate spins on the surface of metals as the source of flux noise in superconducting quantum interference devices and indicate that these spins are able to relax without conserving total magnetization. We present a model of 1/f flux noise in which electron spins on the surface of metals can relax via hyperfine interactions. Our results indicate that flux noise would be significantly reduced in superconducting materials where the most abundant isotopes do not have nuclear moments, such as zinc and lead.

  1. Determination of hyperfine fields orientation in nuclear probe techniques

    Science.gov (United States)

    Szymański, K.; Olszewski, W.; Satuła, D.; Gawryluk, D. J.; Krzton-Maziopa, A.; Kalska-Szostko, B.

    2017-02-01

    One of the most popular nuclear probes, 57Fe is used for the investigation of orientations of hyperfine fields and also for the determination of other important properties. In particular, the orientation of iron magnetic moments can be unambiguously determined, including its signs. Experiments with polarized radiation are presented with regard to selected systems. Orientation of electric field gradient is used for acquiring information about the shape of the texture-free spectra. Applications on the analysis of iron-based superconductors are presented.

  2. Hyperfine interactions: the past, the present and the future

    Energy Technology Data Exchange (ETDEWEB)

    Langouche, Guido, E-mail: guido.langouche@kuleuven.be [Katholieke Universiteit Leuven, Physics Department, Institute of Nuclear and Radiation Physics (Belgium)

    2008-01-15

    Five major hyperfine interaction techniques, detected by nuclear radiation, originated in the short time span between 1950 and 1965. The coincidence with the demographic expansion, especially in Europe, of university education led to the creation of many new research laboratories applying these promising techniques in solid state physics, chemistry and biology. Since the turn of century many of the early pioneers are going into retirement, leading to a decline in activities in Europe, compensated in some degree by an increase in activities outside Europe. The organisation of the 2007 HI/NQI-conference was impeccable and took place in a superb setting. Thanks to all those involved in its organization.

  3. Transitions between hyperfine-structure states of the 2s metastable muonic hydrogen in collision processes

    Energy Technology Data Exchange (ETDEWEB)

    Czaplinski, W.

    1992-12-31

    Hyperfine effects in the symmetric collisions of the 2s metastable muonic hydrogen with hydrogen atoms: (p{mu}){sub 2s} + H, (d{mu}){sub 2s} + D, (t{mu}){sub 2s} + t are presented. Elastic and spin-flip cross sections for the scattering of The 2s muonic atoms are calculated in the two-level approximation as a function of collision energy. The corresponding formulae are derived with inclusion of electron screening and Lamb-shift between 2s and 2p energy levels of the muonic atom. The obtained spin-flip cross sections are about two orders of magnitude higher than their ground state counterparts and are much more influenced by electron screening. The rates of the spin-flip transitions are also calculated and are found to be about three orders of magnitude higher than the decay rate of the 2s state. (author). 65 refs, 15 figs, 4 tabs.

  4. Vibrational branching ratios and hyperfine structure of BH and its suitability for laser cooling

    Science.gov (United States)

    Hendricks, Richard; Holland, Darren; Truppe, Stefan; Sauer, Ben; Tarbutt, Michael

    2014-08-01

    The simple structure of the BH molecule makes it an excellent candidate for direct laser cooling. We measure the branching ratios for the decay of the A^{1}Pi (v'=0) state to vibrational levels of the ground state, X^{1}Sigma^{+}, and find that they are exceedingly favourable for laser cooling. We verify that the branching ratio for the spin-forbidden transition to the intermediate a^{3}Pi state is inconsequentially small. We measure the frequency of the lowest rotational transition of the X state, and the hyperfine structure in the relevant levels of both the X and A states, and determine the nuclear electric quadrupole and magnetic dipole coupling constants. Our results show that, with a relatively simple laser cooling scheme, a Zeeman slower and magneto-optical trap can be used to cool, slow and trap BH molecules.

  5. Vibrational branching ratios and hyperfine structure of $^{11}$BH and its suitability for laser cooling

    CERN Document Server

    Hendricks, R J; Truppe, S; Sauer, B E; Tarbutt, M R

    2014-01-01

    The simple structure of the BH molecule makes it an excellent candidate for direct laser cooling. We measure the branching ratios for the decay of the ${\\rm A}^{1}\\Pi (v'=0)$ state to vibrational levels of the ground state, ${\\rm X}^{1}\\Sigma^{+}$, and find that they are exceedingly favourable for laser cooling. We verify that the branching ratio for the spin-forbidden transition to the intermediate ${\\rm a}^{3}\\Pi$ state is inconsequentially small. We measure the frequency of the lowest rotational transition of the X state, and the hyperfine structure in the relevant levels of both the X and A states, and determine the nuclear electric quadrupole and magnetic dipole coupling constants. Our results show that, with a relatively simple laser cooling scheme, a Zeeman slower and magneto-optical trap can be used to cool, slow and trap BH molecules.

  6. Vibrational branching ratios and hyperfine structure of BH and its suitability for laser cooling

    Directory of Open Access Journals (Sweden)

    Richard eHendricks

    2014-08-01

    Full Text Available The simple structure of the BH molecule makes it an excellent candidate for direct laser cooling. We measure the branching ratios for the decay of the A^{1}Pi (v'=0 state to vibrational levels of the ground state, X^{1}Sigma^{+}, and find that they are exceedingly favourable for laser cooling. We verify that the branching ratio for the spin-forbidden transition to the intermediate a^{3}Pi state is inconsequentially small. We measure the frequency of the lowest rotational transition of the X state, and the hyperfine structure in the relevant levels of both the X and A states, and determine the nuclear electric quadrupole and magnetic dipole coupling constants. Our results show that, with a relatively simple laser cooling scheme, a Zeeman slower and magneto-optical trap can be used to cool, slow and trap BH molecules.

  7. Split Cord Malformations

    Directory of Open Access Journals (Sweden)

    Yurdal Gezercan

    2015-06-01

    Full Text Available Split cord malformations are rare form of occult spinal dysraphism in children. Split cord malformations are characterized by septum that cleaves the spinal canal in sagittal plane within the single or duplicated thecal sac. Although their precise incidence is unknown, split cord malformations are exceedingly rare and represent %3.8-5 of all congenital spinal anomalies. Characteristic neurological, urological, orthopedic clinical manifestations are variable and asymptomatic course is possible. Earlier diagnosis and surgical intervention for split cord malformations is associated with better long-term fuctional outcome. For this reason, diagnostic imaging is indicated for children with associated cutaneous and orthopedic signs. Additional congenital anomalies usually to accompany the split cord malformations. Earlier diagnosis, meticuolus surgical therapy and interdisciplinary careful evaluation and follow-up should be made for good prognosis. [Cukurova Med J 2015; 40(2.000: 199-207

  8. Accuracy of tablet splitting.

    Science.gov (United States)

    McDevitt, J T; Gurst, A H; Chen, Y

    1998-01-01

    We attempted to determine the accuracy of manually splitting hydrochlorothiazide tablets. Ninety-four healthy volunteers each split ten 25-mg hydrochlorothiazide tablets, which were then weighed using an analytical balance. Demographics, grip and pinch strength, digit circumference, and tablet-splitting experience were documented. Subjects were also surveyed regarding their willingness to pay a premium for commercially available, lower-dose tablets. Of 1752 manually split tablet portions, 41.3% deviated from ideal weight by more than 10% and 12.4% deviated by more than 20%. Gender, age, education, and tablet-splitting experience were not predictive of variability. Most subjects (96.8%) stated a preference for commercially produced, lower-dose tablets, and 77.2% were willing to pay more for them. For drugs with steep dose-response curves or narrow therapeutic windows, the differences we recorded could be clinically relevant.

  9. Coded Splitting Tree Protocols

    DEFF Research Database (Denmark)

    Sørensen, Jesper Hemming; Stefanovic, Cedomir; Popovski, Petar

    2013-01-01

    This paper presents a novel approach to multiple access control called coded splitting tree protocol. The approach builds on the known tree splitting protocols, code structure and successive interference cancellation (SIC). Several instances of the tree splitting protocol are initiated, each...... instance is terminated prematurely and subsequently iterated. The combined set of leaves from all the tree instances can then be viewed as a graph code, which is decodable using belief propagation. The main design problem is determining the order of splitting, which enables successful decoding as early...... as possible. Evaluations show that the proposed protocol provides considerable gains over the standard tree splitting protocol applying SIC. The improvement comes at the expense of an increased feedback and receiver complexity....

  10. A theoretical study of the fine and hyperfine interactions in the NCO and CNO radicals

    Science.gov (United States)

    Prasad, Rajendra

    2004-06-01

    The geometries, the harmonic vibrational frequencies, and the Renner-Teller parameter have been reported for the NCO+(X˜ 3Σ-), NCO(X˜ 2Π,Ã2Σ+,B˜ 2Π,2 2Σ+), NCO-(X˜ 1Σ+), CNO+(X˜), CNO(X˜ 2Π,Ã2Σ+,B˜ 2Π,2 2Σ+), and CNO-(X˜ 1Σ+) systems at the full valence-complete active space self-consistent-field (fv-CASSCF) level of theory. The 2Π electronic states of the NCO and CNO radicals have two distinct real vibrational frequencies for the bending modes and these states are subject to the type A Renner-Teller effect. The total energy of CNO+ without zero point energy correction of the linear geometry is ˜31 cm-1 higher than the bent geometry at the fv-CASSCF level and the inversion barrier vanishes after the zero point energy correction; therefore, the ground state of the CNO+ may possess a quasilinear geometry. The spin-orbit coupling constants estimated using atomic mean field Hamiltonian at the fv-CASSCF level of theory are in better agreement with the experimental values. The excitation energies, the electron affinity, and the ionization potential have been computed at the complete active space second order perturbation theory (CASPT2) and the multireference singles and doubles configuration (MRSD-CI) levels of theory. The computed values of the electric hyperfine coupling constants for the 14N atom in the ground state of the NCO radical agree well with the experimental data. The magnetic hyperfine coupling constants (HFCC's) have been estimated employing the configuration selected MRSD-CI and the multireference singles configuration interaction (MRS-CI) methods using iterative natural orbitals (ino) as one particle basis. Sufficiently accurate value of the isotropic contribution to the HFCC's can be obtained using an MRS-CI-ino procedure.

  11. Zeeman effects in the hyperfine structure of atomic iodine photodissociation laser emission.

    Science.gov (United States)

    Hwang, W. C.; Kasper, J. V. V.

    1972-01-01

    Observation of hyperfine structure in laser emission from CF3I and C2F5I photodissociation lasers. Constant magnetic fields affect the time behavior of the emission by changing the relative gains of the hyperfine transitions. Time-varying fields usually present in photodissociation lasers further complicate the emission.

  12. Pressure-dependent hyperfine interactions in NpAl/sub 2/

    Energy Technology Data Exchange (ETDEWEB)

    Litterst, F.J.; Moser, J.; Potzel, W.; Potzel, U.; Kalvius, G.M.; Asch, L.; Gal, J.; Spirlet, J.C.

    1986-12-01

    /sup 237/Np Moessbauer data of NpAl/sub 2/ are reported for pressures up to 90 kbar in a temperature range from 1.5 K to 77 K. Application of pressure yields a continuous reduction of the Curie temperature T/sub c/, of the saturation hyperfine magnetic field and of the isomer shift indicating an increasing delocalization of 5 f electrons. Severe relaxational broadenings of the magnetic patterns are found especially for high pressures and close to T/sub c/. In part these may be connected with interconfigurational fluctuations but major role play fluctuations within the lowest electronic levels of Np at rates in the range of 1-10 GHz.

  13. Resolution of hyperfine transitions in metastable 83Kr using Electromagnetically Induced Transparency

    CERN Document Server

    Kale, Y B; Tiwari, V B; Singh, S; Rawat, H S

    2015-01-01

    Narrow linewidth signals of Electromagnetically Induced Transparency (EIT) in the metastable 83Kr have been observed for the first time. Various hyperfine transitions in 4p55s[3/2]2 to 4p55p[5/2]3 manifolds of 83Kr have been identified through the experimentally observed EIT signals. Some unresolved or poorly resolved hyperfine transitions in saturated absorption spectroscopy (SAS) are clearly resolved in the present work. Using the spectral separation of these EIT identified hyperfine transitions, the magnetic hyperfine constant (A) and the electric quadrupole hyperfine constant (B) are determined with improved accuracy for 4p55s[3/2]2 and 4p55p[5/2]3 manifolds.

  14. Concentric Split Flow Filter

    Science.gov (United States)

    Stapleton, Thomas J. (Inventor)

    2015-01-01

    A concentric split flow filter may be configured to remove odor and/or bacteria from pumped air used to collect urine and fecal waste products. For instance, filter may be designed to effectively fill the volume that was previously considered wasted surrounding the transport tube of a waste management system. The concentric split flow filter may be configured to split the air flow, with substantially half of the air flow to be treated traveling through a first bed of filter media and substantially the other half of the air flow to be treated traveling through the second bed of filter media. This split flow design reduces the air velocity by 50%. In this way, the pressure drop of filter may be reduced by as much as a factor of 4 as compare to the conventional design.

  15. Autler-Townes splitting via frequency upconversion at ultra-low power levels in cold $^{87}$Rb atoms using an optical nanofiber

    CERN Document Server

    Kumar, Ravi; Deasy, Kieran; Chormaic, Síle Nic

    2015-01-01

    The tight confinement of the evanescent light field around the waist of an optical nanofiber makes it a suitable tool for studying nonlinear optics in atomic media. Here, we use an optical nanofiber embedded in a cloud of laser-cooled 87Rb for near-infrared frequency upconversion via a resonant two-photon process. Sub-nW powers of the two-photon beams, at 780 nm and 776 nm, co-propagate through the optical nanofiber and generation of 420 nm photons is observed. A measurement of the Autler-Townes splitting provides a direct measurement of the Rabi frequency of the 780 nm transition. Through this method, dephasings of the system can be studied. In this work, the optical nanofiber is used as an excitation and detection tool simultaneously, and it highlights some of the advantages of using fully fibered systems for nonlinear optics with atoms.

  16. Autler-Townes splitting via frequency up-conversion at ultralow-power levels in cold 87Rb atoms using an optical nanofiber

    Science.gov (United States)

    Kumar, Ravi; Gokhroo, Vandna; Deasy, Kieran; Chormaic, Síle Nic

    2015-05-01

    The tight confinement of the evanescent light field around the waist of an optical nanofiber makes it a suitable tool for studying nonlinear optics in atomic media. Here, we use an optical nanofiber embedded in a cloud of laser-cooled 87Rb for near-infrared frequency up-conversion via a resonant two-photon process. Sub-nW powers of the two-photon radiation, at 780 and 776 nm, copropagate through the optical nanofiber and the generation of 420 nm photons is observed. A measurement of the Autler-Townes splitting provides a direct measurement of the Rabi frequency of the 780 nm transition. Through this method, dephasings of the system can be studied. In this work, the optical nanofiber is used as an excitation and detection tool simultaneously, and it highlights some of the advantages of using fully fibered systems for nonlinear optics with atoms.

  17. Polarized Antenna Splitting Functions

    Energy Technology Data Exchange (ETDEWEB)

    Larkoski, Andrew J.; Peskin, Michael E.; /SLAC

    2009-10-17

    We consider parton showers based on radiation from QCD dipoles or 'antennae'. These showers are built from 2 {yields} 3 parton splitting processes. The question then arises of what functions replace the Altarelli-Parisi splitting functions in this approach. We give a detailed answer to this question, applicable to antenna showers in which partons carry definite helicity, and to both initial- and final-state emissions.

  18. Split-body Processing and Fabrication Weld Manufacturing Technique of Super-long Coal Leveling Bar%超长平煤杆的分体加工组焊制造工艺技术

    Institute of Scientific and Technical Information of China (English)

    张小川; 陆博福

    2015-01-01

    Super-long coal leveling bar has been manufactured successfully by adopting split-body processing and fabrication weld moulding technique.The product quality was sufficient for technical requirement and the processing mode was economical and practical.%采用分体加工、组装焊接成型技术成功制造了超长平煤杆。产品质量符合技术要求,加工方式经济实用。

  19. Nagaoka’s atomic model and hyperfine interactions

    Science.gov (United States)

    INAMURA, Takashi T.

    2016-01-01

    The prevailing view of Nagaoka’s “Saturnian” atom is so misleading that today many people have an erroneous picture of Nagaoka’s vision. They believe it to be a system involving a ‘giant core’ with electrons circulating just outside. Actually, though, in view of the Coulomb potential related to the atomic nucleus, Nagaoka’s model is exactly the same as Rutherford’s. This is true of the Bohr atom, too. To give proper credit, Nagaoka should be remembered together with Rutherford and Bohr in the history of the atomic model. It is also pointed out that Nagaoka was a pioneer of understanding hyperfine interactions in order to study nuclear structure. PMID:27063182

  20. Theoretical Investigation on Hyperfine Structures of Perfluoropolyether Radicals

    Institute of Scientific and Technical Information of China (English)

    DONG Su-li; LIU Ya-jun

    2011-01-01

    The geometries of CF3OCF2, CF3OCFCF3 and CF3OCF2CF2 radicals were investigated by density func tional theory(DFT) method. The calculated results indicate that all the three radicals have pyramidal shapes at their centers, and the aC is one top of the pyramids. Based on the DFT optimized geometries, the hyperfine coupling con stants(hfcc's) of the 19F atoms of the three radicals were calculated by B3LYP, MP2(full) and QCISD(full) methods.The calculated values agree with the experimental values, especially for the a values of Fa, the a values are 125.6× 10-4, 104.2× 10-4, and 83.2× 10-4 T of CF3OCF2, CF3OCFCF3 and CF3OCF2CF2, respectively. These results better explain the experimental observation.

  1. Measurement and modeling of hyperfine parameters in ferroic materials

    CERN Document Server

    Gonçalves, João Nuno; Correia, J G

    This thesis presents the results of perturbed angular correlation (PAC) experiments , an experimental technique which measures the hyperfine interaction at probes (radioactive ions implanted in the materials to study), from which one infers local information on an atomic scale. Furthermore, abinitio calculations using density functional theory electronic obtain results that directly complement the experiments, and are also used for theoretical research. These methods were applied in two families of materials. The manganites, with the possible existence of magnetic, charge, orbital and ferroelectric orders, are of fundamental and technological interest. The experimental results are obtained in the alkaline-earth manganites (Ca, Ba, Sr), with special interest due to the structural variety of possible polymorphs. With probes of Cd and In the stability of the probe and its location in a wide temperature range is established and a comparison with calculations allows the physical interpretation of the results. Cal...

  2. Exploration of hyperfine interaction between constituent quarks via eta productions

    CERN Document Server

    He, Jun; Xu, H S

    2011-01-01

    In this work, the different exchange freedom, one gluon, one pion or Goldstone boson, in constituent quark model is investigated, which is responsible to the hyperfine interaction between constituent quarks, via the combined analysis of the eta production processes, $\\pi^{-}p\\rightarrow\\eta n$ and $\\gamma p\\rightarrow\\eta p$. With the Goldstone-boson exchange, as well as the one-gluon or one-pion exchange, both the spectrum and observables, such as, the differential cross section and polarized beam asymmetry, are fitted to the suggested values of Particle Data Group and the experimental data. The first two types of exchange freedoms give acceptable description of the spectrum and observables while the one pion exchange can not describe the observables and spectrum simultaneously, so can be excluded. The experimental data for the two processes considered here strongly support the mixing angles for two lowest S11 sates and D13 states as about -30 and 6 degree respectively.

  3. Relativistic extended coupled cluster method for magnetic hyperfine structure constant

    CERN Document Server

    Sasmal, Sudip; Nayak, Malaya K; Vaval, Nayana; Pal, Sourav

    2015-01-01

    This article deals with the general implementation of 4-component spinor relativistic extended coupled cluster (ECC) method to calculate first order property of atoms and molecules in their open-shell ground state configuration. The implemented relativistic ECC is employed to calculate hyperfine structure (HFS) constant of alkali metals (Li, Na, K, Rb and Cs), singly charged alkaline earth metal atoms (Be+, Mg+, Ca+ and Sr+) and molecules (BeH, MgF and CaH). We have compared our ECC results with the calculations based on restricted active space configuration interaction (RAS-CI) method. Our results are in better agreement with the available experimental values than those of the RAS-CI values.

  4. Control of inhomogeneous atomic ensembles of hyperfine qudits

    CERN Document Server

    Mischuck, Brian E; Deutsch, Ivan H

    2011-01-01

    We study the ability to control d-dimensional quantum systems (qudits) encoded in the hyperfine spin of alkali-metal atoms through the application of radio- and microwave-frequency magnetic fields in the presence of inhomogeneities in amplitude and detuning. Such a capability is essential to the design of robust pulses that mitigate the effects of experimental uncertainty and also for application to tomographic addressing of particular members of an extended ensemble. We study the problem of preparing an arbitrary state in the Hilbert space from an initial fiducial state. We prove that inhomogeneous control of qudit ensembles is possible based on a semi-analytic protocol that synthesizes the target through a sequence of alternating rf and microwave-driven SU(2) rotations in overlapping irreducible subspaces. Several examples of robust control are studied, and the semi-analytic protocol is compared to a brute force, full numerical search. For small inhomogeneities, < 1%, both approaches achieve average fide...

  5. Split-plot designs for multistage experimentation

    DEFF Research Database (Denmark)

    Kulahci, Murat; Tyssedal, John

    2016-01-01

    at the same time will be more efficient. However, there have been only a few attempts in the literature to provide an adequate and easy-to-use approach for this problem. In this paper, we present a novel methodology for constructing two-level split-plot and multistage experiments. The methodology is based...... be accommodated in each stage. Furthermore, split-plot designs for multistage experiments with good projective properties are also provided....

  6. HCN hyperfine ratio analysis of massive molecular clumps

    Science.gov (United States)

    Schap, W. J.; Barnes, P. J.; Ordoñez, A.; Ginsburg, A.; Yonekura, Y.; Fukui, Y.

    2017-03-01

    We report a new analysis protocol for HCN hyperfine data, based on the PYSPECKIT package, and results of using this new protocol to analyse a sample area of seven massive molecular clumps from the Census of High- and Medium-mass Protostars (CHaMP) survey, in order to derive maps of column density for this species. There is a strong correlation between the HCN integrated intensity, IHCN, and previously reported I_HCO+ in the clumps, but I_N_{2H+} is not well correlated with either of these other two 'dense gas tracers'. The four fitted parameters from PYSPECKIT in this region fall in the range of VLSR = 8-10 km s-1, σV = 1.2-2.2 km s-1, Tex = 4-15 K, and τ = 0.2-2.5. These parameters allow us to derive a column density map of these clouds, without limiting assumptions about the excitation or opacity. A more traditional (linear) method of converting IHCN to total mass column gives much lower clump masses than our results based on the hyperfine analysis. This is primarily due to areas in the sample region of low I, low Tex, and high τ. We conclude that there may be more dense gas in these massive clumps not engaged in massive star formation than previously recognized. If this result holds for other clouds in the CHaMP sample, it would have dramatic consequences for the calibration of the Kennicutt-Schmidt star formation laws, including a large increase in the gas depletion time-scale in such regions.

  7. Magnetic Response and Hyperfine Magnetic Fields at Fe Sites of Sr{sub 3}Fe{sub 2}MO{sub 9} (M = Mo, Te, W, U) Double-Perovskites

    Energy Technology Data Exchange (ETDEWEB)

    Baum, L. A.; Stewart, S. J.; Mercader, R. C. [Universidad Nacional de La Plata, Departamento de Fisica, IFLP, Facultad de Ciencias Exactas (Argentina); Greneche, J. M., E-mail: greneche@univ-lemans.fr [Universite du Maine, Laboratoire de Physique de L' Etat Condense UMR CNRS 6087 (France)

    2004-12-15

    We have studied the isostructural series of double-perovskites Sr{sub 3}Fe{sub 2}MO{sub 9} (M=Mo, Te, W, U) by Moessbauer spectrometry and AC susceptibility measurements. The hyperfine structure of Moessbauer spectra at room temperature is attributed to the presence of high spin state Fe{sup 3+} ions sensing both static and fluctuating magnetic hyperfine fields with different relative areas that depend on M. The magnetically split signal - indistinguishable from the background in the Mo compound spectrum - increases with the Fe-site disorder in the sequence Mosplit and display hyperfine fields that range from 49 up to 53 T. Coincident with the X-ray and neutron diffraction results, the hyperfine parameters are consistent with Fe atoms centered in oxygen octahedral units, coordinated to different numbers of M-centered octahedra. The AC susceptibility response is {chi}'{sub max} {approx}3.5x10{sup -5} emu/g.Oe for the Mo compound and increases for the W, Te and U compounds with values of {chi}'{sub max} 1.6x10{sup -4}, 3.0x10{sup -4}, and 9.4x10{sup -3} emu/g.Oe, respectively. The out-of-phase component, {chi}'', could only be detected for the U compound. Its frequency dependence displays a shift that denotes a spin-glass-like state arising from the chemical disorder.

  8. Measurement of hyperfine structure and isotope shifts in the 580.56nm line of 142_145_146_148_150_Nd+

    Institute of Scientific and Technical Information of China (English)

    Ma Hong-Liang

    2005-01-01

    Istope shifts and hyperfine spectrum of singly ionized neodymium ion was measured by collinear fast-ion-beam laser spectroscopy. The hyperfine A constants and B constants are obtained for the (23230)o9/2 level and 4f45d6K9/2 level, respectively. The optical isotope shifts between seven isotopes in the 580.56 nm of 142-145;146;148;150hNd+ line are determined. The configuration admixtures for (23230)o9/2 level were quantitatively analysed to be 4f46p,4f35d2,and 4f35d6p with mixing coefficients of 67%, 5%,and 28%,respectively.

  9. Fine- and hyperfine-structure effects in molecular photoionization: I. General theory and direct photoionization

    CERN Document Server

    Germann, Matthias

    2016-01-01

    We develop a model for predicting fine- and hyperfine intensities in the direct photoionization of molecules based on the separability of electron and nuclear spin states from vibrational-electronic states. Using spherical tensor algebra, we derive highly symmetrized forms of the squared photoionization dipole matrix elements from which which we derive the salient selection and propensity rules for fine- and hyperfine resolved photoionizing transitions. Our theoretical results are validated by the analysis of the fine-structure resolved photoelectron spectrum of O$_2$ (reported by H. Palm and F. Merkt, Phys. Rev. Lett. 81, 1385 (1998)) and are used for predicting hyperfine populations of molecular ions produced by photoionization.

  10. (O)Mega Split

    CERN Document Server

    Benakli, Karim; Goodsell, Mark

    2015-01-01

    We study two realisations of the Fake Split Supersymmetry Model (FSSM), the simplest model that can easily reproduce the experimental value of the Higgs mass for an arbitrarily high supersymmetry scale, as a consequence of swapping higgsinos for equivalent states, fake higgsinos, with suppressed Yukawa couplings. If the LSP is identified as the main Dark matter component, then a standard thermal history of the Universe implies upper bounds on the supersymmetry scale, which we derive. On the other hand, we show that renormalisation group running of soft masses above the supersymmetry scale barely constrains the model - in stark contrast to Split Supersymmetry - and hence we can have a "Mega Split" spectrum even with all of these assumptions and constraints, which include the requirements of a correct relic abundance, a gluino life-time compatible with Big Bang Nucleosynthesis and absence of signals in present direct detection experiments of inelastic dark matter. In an appendix we describe a related scenario, ...

  11. Splitting Ward identity

    Energy Technology Data Exchange (ETDEWEB)

    Safari, Mahmoud [Institute for Research in Fundamental Sciences (IPM), School of Particles and Accelerators, P.O. Box 19395-5531, Tehran (Iran, Islamic Republic of)

    2016-04-15

    Within the background-field framework we present a path integral derivation of the splitting Ward identity for the one-particle irreducible effective action in the presence of an infrared regulator, and make connection with earlier works on the subject. The approach is general in the sense that it does not rely on how the splitting is performed. This identity is then used to address the problem of background dependence of the effective action at an arbitrary energy scale. We next introduce the modified master equation and emphasize its role in constraining the effective action. Finally, application to general gauge theories within the geometric approach is discussed. (orig.)

  12. Split Malcev Algebras

    Indian Academy of Sciences (India)

    Antonio J Calderón Martín; Manuel Forero Piulestán; José M Sánchez Delgado

    2012-05-01

    We study the structure of split Malcev algebras of arbitrary dimension over an algebraically closed field of characteristic zero. We show that any such algebras is of the form $M=\\mathcal{U}+\\sum_jI_j$ with $\\mathcal{U}$ a subspace of the abelian Malcev subalgebra and any $I_j$ a well described ideal of satisfying $[I_j, I_k]=0$ if ≠ . Under certain conditions, the simplicity of is characterized and it is shown that is the direct sum of a semisimple split Lie algebra and a direct sum of simple non-Lie Malcev algebras.

  13. Role of zero-point vibrational corrections to carbon hyperfine coupling constants in organic π radicals

    Science.gov (United States)

    Chen, X.; Rinkevicius, Z.; Ruud, K.; Ågren, H.

    2013-02-01

    By analyzing a set of organic π radicals, we demonstrate that zero-point vibrational corrections give significant contributions to carbon hyperfine coupling constants, in one case even inducing a sign reversal for the coupling constant. We discuss the implications of these findings for the computational analysis of electron paramagnetic spectra based on hyperfine coupling constants evaluated at the equilibrium geometry of radicals. In particular, we note that a dynamical description that involves the nuclear motion is in many cases necessary in order to achieve a semi-quantitatively predictive theory for carbon hyperfine coupling constants. In addition, we discuss the implications of the strong dependence of the carbon hyperfine coupling constants on the zero-point vibrational corrections for the selection of exchange-correlation functionals in density functional theory studies of these constants.

  14. The Splitting Loope

    Science.gov (United States)

    Wilkins, Jesse L. M.; Norton, Anderson

    2011-01-01

    Teaching experiments have generated several hypotheses concerning the construction of fraction schemes and operations and relationships among them. In particular, researchers have hypothesized that children's construction of splitting operations is crucial to their construction of more advanced fractions concepts (Steffe, 2002). The authors…

  15. Pendulum separatrix splitting

    CERN Document Server

    Gallavotti, G; Mastropietro, V

    1997-01-01

    An exact expression for the determinant of the splitting matrix is derived: it allows us to analyze the asympotic behaviour needed to amend the large angles theorem proposed in Ann. Inst. H. Poincaré, B-60, 1, 1994. The asymptotic validity of Melnokov's formulae is proved for the class of models considered, which include polynomial perturbations.

  16. Hole spin dephasing time associated to hyperfine interaction in quantum dots

    OpenAIRE

    Testelin, C.; Bernardot, F.; Eble, B.; Chamarro, M.

    2009-01-01

    The spin interaction of a hole confined in a quantum dot with the surrounding nuclei is described in terms of an effective magnetic field. We show that, in contrast to the Fermi contact hyperfine interaction for conduction electrons, the dipole-dipole hyperfine interaction is anisotropic for a hole, for both pure or mixed hole states. We evaluate the coupling constants of the hole-nuclear interaction and demonstrate that they are only one order of magnitude smaller than the coupling constants...

  17. Density functional theory predictions of isotropic hyperfine coupling constants.

    Science.gov (United States)

    Hermosilla, L; Calle, P; García de la Vega, J M; Sieiro, C

    2005-02-17

    The reliability of density functional theory (DFT) in the determination of the isotropic hyperfine coupling constants (hfccs) of the ground electronic states of organic and inorganic radicals is examined. Predictions using several DFT methods and 6-31G, TZVP, EPR-III and cc-pVQZ basis sets are made and compared to experimental values. The set of 75 radicals here studied was selected using a wide range of criteria. The systems studied are neutral, cationic, anionic; doublet, triplet, quartet; localized, and conjugated radicals, containing 1H, 9Be, 11B, 13C, 14N, 17O, 19F, 23Na, 25Mg, 27Al, 29Si, 31P, 33S, and 35Cl nuclei. The considered radicals provide 241 theoretical hfcc values, which are compared with 174 available experimental ones. The geometries of the studied systems are obtained by theoretical optimization using the same functional and basis set with which the hfccs were calculated. Regression analysis is used as a basic and appropriate methodology for this kind of comparative study. From this analysis, we conclude that DFT predictions of the hfccs are reliable for B3LYP/TZVP and B3LYP/EPR-III combinations. Both functional/basis set scheme are the more useful theoretical tools for predicting hfccs if compared to other much more expensive methods.

  18. Spin-dependent recombination and hyperfine interaction at deep defects

    Science.gov (United States)

    Ivchenko, E. L.; Bakaleinikov, L. A.; Kalevich, V. K.

    2015-05-01

    We present a theoretical study of optical electron-spin orientation and spin-dependent Shockley-Read-Hall recombination in the longitudinal magnetic field, taking into account the hyperfine coupling between the bound-electron spin and the nuclear spin of a deep paramagnetic center. The master rate equations for the coupled system are extended to describe the nuclear spin relaxation by using two distinct relaxation times, τn 1 and τn 2, respectively, for defect states with one and two (singlet) bound electrons. The general theory is developed for an arbitrary value of the nuclear spin I . The magnetic-field and excitation-power dependencies of the electron and nuclear spin polarizations are calculated for the value of I =1 /2 . In this particular case the nuclear effects can be taken into account by a simple replacement of the bound-electron spin relaxation time by an effective time dependent on free-electron and hole densities and free-electron spin polarization. The role of nuclear spin relaxation is visualized by isolines of the electron spin polarization on a two-dimensional graph with the axes log2(τn 1) and log2(τn 2) .

  19. Hyperfine Coupling Constants from Internally Contracted Multireference Perturbation Theory.

    Science.gov (United States)

    Shiozaki, Toru; Yanai, Takeshi

    2016-09-13

    We present an accurate method for calculating hyperfine coupling constants (HFCCs) based on the complete active space second-order perturbation theory (CASPT2) with full internal contraction. The HFCCs are computed as a first-order property using the relaxed CASPT2 spin-density matrix that takes into account orbital and configurational relaxation due to dynamical electron correlation. The first-order unrelaxed spin-density matrix is calculated from one- and two-body spin-free counterparts that are readily available in the CASPT2 nuclear gradient program [M. K. MacLeod and T. Shiozaki, J. Chem. Phys. 142, 051103 (2015)], whereas the second-order part is computed directly using the newly extended automatic code generator. The relaxation contribution is then calculated from the so-called Z-vectors that are available in the CASPT2 nuclear gradient program. Numerical results are presented for the CN and AlO radicals, for which the CASPT2 values are comparable (or, even superior in some cases) to the ones computed by the coupled-cluster and density matrix renormalization group methods. The HFCCs for the hexaaqua complexes with V(II), Cr(III), and Mn(II) are also presented to demonstrate the accuracy and efficiency of our code.

  20. Hyperfine coupling constants from internally contracted multireference perturbation theory

    CERN Document Server

    Shiozaki, Toru

    2016-01-01

    We present an accurate method for calculating hyperfine coupling constants (HFCCs) based on the complete active space second-order perturbation theory (CASPT2) with full internal contraction. The HFCCs are computed as a first-order property using the relaxed CASPT2 spin-density matrix that takes into account orbital and configurational relaxation due to dynamical electron correlation. The first-order unrelaxed spin-density matrix is calculated from one- and two-body spin-free counterparts that are readily available in the CASPT2 nuclear gradient program [M. K. MacLeod and T. Shiozaki, J. Chem. Phys. 142, 051103 (2015)], whereas the second-order part is computed directly using the newly extended automatic code generator. The relaxation contribution is then calculated from the so-called Z-vectors that are available in the CASPT2 nuclear gradient program. Numerical results are presented for the CN and AlO radicals, for which the CASPT2 values are comparable (or, even superior in some cases) to the ones computed ...

  1. Determination of Hyperfine Splittings of Biradical Termini by Combining Biradical Trapping and Time-Resolved ESR Techniques

    Science.gov (United States)

    1993-01-01

    detection of spin-polarized short-lived biradicals has been shown to be a valuable tool in studying the-mechanisms of photochemical reactions and in the...investigation of the propoerties of biradicals . However,*some important spectroscopic features of the S species are not readily available because of...certain peculiarities of biradical ESR spectra. This difficulty can be overcome through the conservation of spin polarizatioi ,by the controlled scavenging

  2. Energy, fine structure, hyperfine structure, and radiative transition rates of the high-lying multi-excited states for B-like neon

    Science.gov (United States)

    Zhang, Chun Mei; Chen, Chao; Sun, Yan; Gou, Bing Cong; Shao, Bin

    2015-04-01

    The Rayleigh-Ritz variational method with multiconfiguration interaction wave functions is used to obtain the energies of high-lying multi-excited quartet states 1 s 22 s2 pnl and 1 s 22 p 2 nl 4Pe,o ( n ≥ 2) in B-like neon, including the mass polarization and relativistic corrections. The fine structure and hyperfine structure of the excited quartet states for this system are investigated. Configuration structures of the high-lying multi-excited series are further identified by relativistic corrections and fine structure splittings. The transition rates and wavelengths are also calculated. Calculated wavelengths include the quantum electrodynamic effects. The results are compared with other theoretical and experimental data in the literature.

  3. Fee splitting in ophthalmology.

    Science.gov (United States)

    Levin, Alex V; Ganesh, Anuradha; Al-Busaidi, Ahmed

    2011-02-01

    Fee splitting and co-management are common practices in ophthalmology. These arrangements may conflict with the ethical principles governing the doctor-patient relationship, may constitute professional misconduct, and at times, may be illegal. Implications and perceptions of these practices may vary between different cultures. Full disclosure to the patient may minimize the adverse effects of conflicts of interest that arise from these practices, and may thereby allow these practices to be deemed acceptable by some cultural morays, professional guidelines, or by law. Disclosure does not necessarily relieve the physician from a potential ethical compromise. This review examines the practice of fee splitting in ophthalmology, its legal implications, the policies or guidelines governing such arrangements, and the possible ethical ramifications. A comparative view between 3 countries, Canada, the United States, and Oman, was conducted; illustrating that even in disparate cultures, there may be some universality to the application of ethical principles.

  4. Syntax for Split Preorders

    CERN Document Server

    Dosen, K

    2009-01-01

    A split preorder is a preordering relation on the disjoint union of two sets, which function as source and target when one composes split preorders. The paper presents by generators and equations the category SplPre, whose arrows are the split preorders on the disjoint union of two finite ordinals. The same is done for the subcategory Gen of SplPre, whose arrows are equivalence relations, and for the category Rel, whose arrows are the binary relations between finite ordinals, and which has an isomorphic image within SplPre by a map that preserves composition, but not identity arrows. It was shown previously that SplPre and Gen have an isomorphic representation in Rel in the style of Brauer. The syntactical presentation of Gen and Rel in this paper exhibits the particular Frobenius algebra structure of Gen and the particular bialgebraic structure of Rel, the latter structure being built upon the former structure in SplPre. This points towards algebraic modelling of various categories motivated by logic, and re...

  5. Relativistic many-body calculation of energies, lifetimes, polarizabilities, blackbody radiative shift, and hyperfine constants in Lu2 +

    Science.gov (United States)

    Safronova, U. I.; Safronova, M. S.; Johnson, W. R.

    2016-09-01

    Energy levels of 30 low-lying states of Lu2 + and allowed electric-dipole matrix elements between these states are evaluated using a relativistic all-order method in which all single, double, and partial triple excitations of Dirac-Fock wave functions are included to all orders of perturbation theory. Matrix elements are critically evaluated for their accuracy and recommended values of the matrix elements are given together with uncertainty estimates. Line strengths, transition rates, and lifetimes of the metastable 5 d3 /2 and 5 d5 /2 states are calculated. Recommended values are given for static polarizabilities of the 6 s , 5 d , and 6 p states and tensor polarizabilities of the 5 d and 6 p3 /2 states. Uncertainties of the polarizability values are estimated in all cases. The blackbody radiation shift of the 6 s1 /2-5 d5 /2 transition frequency of the Lu2 + ion is calculated with the aid of the recommended scalar polarizabilities of the 6 s1 /2 and 5 d5 /2 states. Finally, A and B hyperfine constants are determined for states of 2+175Lu with n ≤9 . This work provides recommended values of transition matrix elements, polarizabilities, and hyperfine constants of Lu2 +, critically evaluated for accuracy, for benchmark tests of high-precision theoretical methodology and planning of future experiments.

  6. Hyperfine excitation of C2H and C2D by para-H2

    Science.gov (United States)

    Dumouchel, Fabien; Lique, François; Spielfiedel, Annie; Feautrier, Nicole

    2017-10-01

    The [C2H]/[C2D] abundance ratio is a useful tool to explore the physical and chemical conditions of cold molecular clouds. Hence, an accurate determination of both the C2H and C2D abundances is of fundamental interest. Due to the low density of the interstellar medium, the population of the energy levels of the molecules is not at local thermodynamical equilibrium. Thus, the accurate modelling of the emission spectra requires the calculation of collisional rate coefficients with the most abundant interstellar species. Hence, we provide rate coefficients for the hyperfine excitation of C2H and C2D by para-H2(j=0), the most abundant collisional partner in cold molecular clouds. State-to-state rate coefficients between the lowest levels were computed for temperatures ranging from 5 to 80 K. For both isotopologues, the Δj = ΔF propensity rule is observed. The comparison between C2H and C2D rate coefficients shows that differences by up to a factor of two exist, mainly for Δj = ΔN = 1 transitions. The new rate coefficients will significantly help in the interpretation of recent observed spectra.

  7. Hyperfine interaction and tuning of magnetic anisotropy of Cu doped CoFe2O4 ferrite nanoparticles

    Science.gov (United States)

    Batoo, Khalid Mujasam; Salah, Dina; Kumar, Gagan; Kumar, Arun; Singh, Mahavir; Abd El-sadek, M.; Mir, Feroz Ahmad; Imran, Ahamad; Jameel, Daler Adil

    2016-08-01

    Ferrimagnetic oxides may contain single or multi domain particles which get converted into superparamagnetic state near a critical size. To explore the existence of these particles, we have made Mössbauer and magnetic studies of Cu2+ substitution effect in CoFe2-xO4 Ferrites (0.0, 0.1, 0.2, 0.3, 0.4, and 0.5). All the samples have a cubic spinel structure with lattice parameters increasing linearly with increase in Cu content. The hysteresis loops yield a saturation magnetization, coercive field, and remanent magnetization that vary significantly with Cu content. The magnetic hysteresis curves shows a reduction in saturation magnetization and an increase in coercitivity with Cu2+ ion substitution. The anisotropy constant, K1, is found strongly dependent on the composition of Cu2+ ions. The variation of saturation magnetization with increasing Cu2+ ion content has been explained in the light of Neel's molecular field theory. Mössbauer spectra at room temperature shows two ferrimagnetically relaxed Zeeman sextets. The dependence of Mössbauer parameters such as isomer shift, quadrupole splitting, line width and hyperfine magnetic field on Cu2+ ion concentration have been discussed.

  8. MEASUREMENT OF HYPERFINE COUPLING CONSTANTS OF THE EXCITED STATES 4f7(8S07/2)6p3/2(7/2, 3/2) IN 151,153Eu+

    Institute of Scientific and Technical Information of China (English)

    MA HONG-LIANG; YANG FU-JIA

    2001-01-01

    Hyperfine structure spectra of singly ionized europium have been measured by collinear fast-ion-beam laser spectroscopy. All the spectral lines were resolved and the magnetic dipole and electric quadrupole coupling constants of the metastable and excited levels were determined.

  9. Structural properties and hyperfine characterization of Sn-substituted goethites

    Energy Technology Data Exchange (ETDEWEB)

    Larralde, A.L. [INQUIMAE, Departamento de Quimica Inorganica, Analitica y Quimica Fisica, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires (Argentina); Ramos, C.P. [Departamento de Fisica de la Materia Condensada, GIyA - CAC - CNEA, Av. Gral. Paz 1499 (1650), San Martin, Bs. As. (Argentina); Arcondo, B. [Departamento de Fisica, Facultad de Ingenieria, Universidad de Buenos Aires, Av. Paseo Colon 850 (C1063ACV), Bs. As. (Argentina); Tufo, A.E. [INQUIMAE, Departamento de Quimica Inorganica, Analitica y Quimica Fisica, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires (Argentina); Saragovi, C. [Departamento de Fisica de la Materia Condensada, GIyA - CAC - CNEA, Av. Gral. Paz 1499 (1650), San Martin, Bs. As. (Argentina); Sileo, E.E., E-mail: sileo@qi.fcen.uba.ar [INQUIMAE, Departamento de Quimica Inorganica, Analitica y Quimica Fisica, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires (Argentina)

    2012-04-16

    Highlights: Black-Right-Pointing-Pointer Pure and tin-doped goethites were synthesized from Sn(II) solutions at ambient pressure and 70 Degree-Sign C. Black-Right-Pointing-Pointer The Rietveld refinement of PXRD data indicated that Sn partially substituted the Fe(III) ions. Black-Right-Pointing-Pointer The substitution provoked unit cell expansion, and a distortion of the coordination polyhedron. Black-Right-Pointing-Pointer {sup 119}Sn Moessbauer spectroscopy revealed that Sn(II) is incorporated as Sn(IV). Black-Right-Pointing-Pointer {sup 57}Fe Moessbauer spectroscopy showed a lower magnetic coupling as tin concentration increased. - Abstract: Tin-doped goethites obtained by a simple method at ambient pressure and 70 Degree-Sign C were characterized by inductively coupled plasma atomic emission spectrometry, scanning electron microscopy, Rietveld refinement of powder X-ray diffraction data, and {sup 57}Fe and {sup 119}Sn Moessbauer spectroscopy. The particles size and the length to width ratios decreased with tin-doping. Sn partially substituted the Fe(III) ions provoking unit cell expansion and increasing the crystallinity of the particles with enlarged domains that grow in the perpendicular and parallel directions to the anisotropic broadening (1 1 1) axis. Intermetallic E, E Prime and DC distances also change although the variations are not monotonous, indicating different variations in the coordination polyhedron. In general, the Sn-substituted samples present larger intermetallic distances than pure goethite, and the greatest change is shown in the E Prime distance which coincides with the c-parameter. {sup 119}Sn Moessbauer spectroscopy revealed that Sn(II) is incorporated as Sn(IV) in the samples. On the other hand, Fe(II) presence was not detected by {sup 57}Fe Moessbauer spectroscopy, suggesting the existence of vacancies in the Sn-doped samples. A lower magnetic coupling is also evidenced from the average magnetic hyperfine field values obtained as tin

  10. Salt splitting with ceramic membranes

    Energy Technology Data Exchange (ETDEWEB)

    Kurath, D. [Pacific Northwest National Lab., Richland, WA (United States)

    1996-10-01

    The purpose of this task is to develop ceramic membrane technologies for salt splitting of radioactively contaminated sodium salt solutions. This technology has the potential to reduce the low-level waste (LLW) disposal volume, the pH and sodium hydroxide content for subsequent processing steps, the sodium content of interstitial liquid in high-level waste (HLW) sludges, and provide sodium hydroxide free of aluminum for recycle within processing plants at the DOE complex. Potential deployment sites include Hanford, Savannah River, and Idaho National Engineering Laboratory (INEL). The technical approach consists of electrochemical separation of sodium ions from the salt solution using sodium (Na) Super Ion Conductors (NaSICON). As the name implies, sodium ions are transported rapidly through these ceramic crystals even at room temperatures.

  11. Measurement of the electronic transition dipole moment by Autler-Townes splitting: Comparison of three- and four-level excitation schemes for the Na2 A 1Sigma(u)+ - X 1Sigma(g)+ system.

    Science.gov (United States)

    Ahmed, E; Hansson, A; Qi, P; Kirova, T; Lazoudis, A; Kotochigova, S; Lyyra, A M; Li, L; Qi, J; Magnier, S

    2006-02-28

    We present a fundamentally new approach for measuring the transition dipole moment of molecular transitions, which combines the benefits of quantum interference effects, such as the Autler-Townes splitting, with the familiar R-centroid approximation. This method is superior to other experimental methods for determining the absolute value of the R-dependent electronic transition dipole moment function mu(e)(R), since it requires only an accurate measurement of the coupling laser electric field amplitude and the determination of the Rabi frequency from an Autler-Townes split fluorescence spectral line. We illustrate this method by measuring the transition dipole moment matrix element for the Na2 A 1Sigma(u)+ (v' = 25, J' = 20e)-X 1Sigma(g)+ (v" = 38, J" = 21e) rovibronic transition and compare our experimental results with our ab initio calculations. We have compared the three-level (cascade) and four-level (extended Lambda) excitation schemes and found that the latter is preferable in this case for two reasons. First, this excitation scheme takes advantage of the fact that the coupling field lower level is outside the thermal population range. As a result vibrational levels with larger wave function amplitudes at the outer turning point of vibration lead to larger transition dipole moment matrix elements and Rabi frequencies than those accessible from the equilibrium internuclear distance of the thermal population distribution. Second, the coupling laser can be "tuned" to different rovibronic transitions in order to determine the internuclear distance dependence of the electronic transition dipole moment function in the region of the R-centroid of each coupling laser transition. Thus the internuclear distance dependence of the transition moment function mu(e)(R) can be determined at several very different values of the R centroid. The measured transition dipole moment matrix element for the Na2 A 1Sigma(u)+ (v' = 25, J' = 20e)-X 1Sigma(g)+ (v" = 38, J" = 21e

  12. Magnetic properties and hyperfine interactions in Cr8, Cr7Cd, and Cr7Ni molecular rings from 19F-NMR

    Science.gov (United States)

    Bordonali, L.; Garlatti, E.; Casadei, C. M.; Furukawa, Y.; Lascialfari, A.; Carretta, S.; Troiani, F.; Timco, G.; Winpenny, R. E. P.; Borsa, F.

    2014-04-01

    A detailed experimental investigation of the 19F nuclear magnetic resonance is made on single crystals of the homometallic Cr8 antiferromagnetic molecular ring and heterometallic Cr7Cd and Cr7Ni rings in the low temperature ground state. Since the F- ion is located midway between neighboring magnetic metal ions in the ring, the 19F-NMR spectra yield information about the local electronic spin density and 19F hyperfine interactions. In Cr8, where the ground state is a singlet with total spin ST = 0, the 19F-NMR spectra at 1.7 K and low external magnetic field display a single narrow line, while when the magnetic field is increased towards the first level crossing field, satellite lines appear in the 19F-NMR spectrum, indicating a progressive increase in the Boltzmann population of the first excited state ST = 1. In the heterometallic rings, Cr7Cd and Cr7Ni, whose ground state is magnetic with ST = 3/2 and ST = 1/2, respectively, the 19F-NMR spectrum has a complicated structure which depends on the strength and orientation of the magnetic field, due to both isotropic and anisotropic transferred hyperfine interactions and classical dipolar interactions. From the 19F-NMR spectra in single crystals we estimated the transferred hyperfine constants for both the F--Ni2+ and the F--Cd2+ bonds. The values of the hyperfine constants compare well to the ones known for F--Ni2+ in KNiF3 and NiF2 and for F--Cr3+ in K2NaCrF6. The results are discussed in terms of hybridization of the 2s, 2p orbitals of the F- ion and the d orbitals of the magnetic ion. Finally, we discuss the implications of our results for the electron-spin decoherence.

  13. Technical Skills Required in Split Liver Transplantation.

    Science.gov (United States)

    Liu, Huanqiu; Li, Ruijun; Fu, Jinling; He, Qianyan; Li, Ji

    2016-07-01

    The number of liver grafts obtained from a cadaver can be greatly increased with the application of split liver transplantation. In the last 10 years, pediatric waiting list mortality has been reduced significantly with the use of this form of liver transplantation, which has 2 major forms. In its most commonly used form, the liver can be transplanted into 1 adult and 1 child by splitting it into a right extended and a left lateral graft. For adult and pediatric recipients, the results of this procedure are comparable to those of whole-organ techniques. In another form, 2 hemi-grafts are obtained by splitting the liver, which can be transplanted into a medium-sized adult (the right side) and a large child/small adult (the left side). The adult liver graft pool is expanded through the process of full right/full left splitting; but it is also a critical technique when one considers the knowledge required of the potential anatomic variations and the high technical skill level needed. In this review, we provide some basic insights into the technical and anatomical aspects of these 2 forms of split liver transplantation and present an updated summary of both forms.

  14. Split Q-balls

    Science.gov (United States)

    Bazeia, D.; Losano, L.; Marques, M. A.; Menezes, R.

    2017-02-01

    We investigate the presence of non-topological solutions of the Q-ball type in (1 , 1) spacetime dimensions. The model engenders the global U (1) symmetry and is of the k-field type, since it contains a new term, of the fourth-order power in the derivative of the complex scalar field. It supports analytical solution of the Q-ball type which is stable quantum mechanically. The new solution engenders an interesting behavior, with the charge and energy densities unveiling a splitting profile.

  15. Trap split with Laguerre-Gaussian beams

    CERN Document Server

    Kazemi, Seyedeh Hamideh; Mahmoud, Mohammad

    2016-01-01

    The optical trapping techniques have been extensively used in physics, biophysics, micro-chemistry, and micro-mechanics to allow trapping and manipulation of materials ranging from particles, cells, biological substances, and polymers to DNA and RNA molecules. In this Letter, we present a convenient and effective way to generate a novel phenomenon of trapping, named trap split, in a conventional four-level double-$\\Lambda$ atomic system driven by four femtosecond Laguerre-Gaussian laser pulses. We find that trap split can be always achieved when atoms are trapped by such laser pulses, as compared to Gaussian ones. This work would greatly facilitate the trapping and manipulating the particles and generation of trap split. It may also suggest the possibility of extension into new research fields, such as micro-machining and biophysics.

  16. Direct measurement of excited-state dipole matrix elements using electromagnetically induced transparency in the hyperfine Paschen-Back regime

    Science.gov (United States)

    Whiting, Daniel J.; Keaveney, James; Adams, Charles S.; Hughes, Ifan G.

    2016-04-01

    Applying large magnetic fields to gain access to the hyperfine Paschen-Back regime can isolate three-level systems in a hot alkali metal vapors, thereby simplifying usually complex atom-light interactions. We use this method to make the first direct measurement of the || matrix element in 87Rb. An analytic model with only three levels accurately models the experimental electromagnetically induced transparency spectra and extracted Rabi frequencies are used to determine the dipole matrix element. We measure || =(2.290 ±0 .002stat±0 .04syst) e a0 , which is in excellent agreement with the theoretical calculations of Safronova, Williams, and Clark [Phys. Rev. A 69, 022509 (2004), 10.1103/PhysRevA.69.022509].

  17. Direct measurement of excited-state dipole matrix elements using electromagnetically induced transparency in the hyperfine Paschen-Back regime

    CERN Document Server

    Whiting, Daniel J; Adams, Charles S; Hughes, Ifan G

    2016-01-01

    Applying large magnetic fields to gain access to the hyperfine Paschen-Back regime can isolate three-level systems in a hot alkali metal vapors, thereby simplifying usually complex atom-light interactions. We use this method to make the first direct measurement of the $|\\langle\\mathrm{5P}| er||\\mathrm{5D}\\rangle|$ matrix element in $^{87}$Rb. An analytic model with only three-levels accurately models the experimental electromagnetically induced transparency spectra and extracted Rabi-frequencies are used to determine the dipole matrix element. We measure $|\\langle\\mathrm{5P}_{3/2}|er||\\mathrm{5D}_{5/2}\\rangle| = (2.290\\pm0.002_{\\rm stat}\\pm0.05_{\\rm syst})~ea_{0}$ which is in excellent agreement with the theoretical calculations of Safronova, Williams and Clark, Phys. Rev. A 69(2), 022509 (2004).

  18. Muonium hyperfine parameters in Si{sub 1-} {sub x} Ge {sub x} alloys

    Energy Technology Data Exchange (ETDEWEB)

    King, Philip [ISIS Facility, Rutherford Appleton Laboratory, Chilton, Oxfordshire OX11 0QX (United Kingdom)]. E-mail: p.j.c.king@rl.ac.uk; Lichti, Roger [Physics Department, Texas Tech University, Lubbock, TX 79409-1051 (United States); Cottrell, Stephen [ISIS Facility, Rutherford Appleton Laboratory, Chilton, Oxfordshire OX11 0QX (United Kingdom); Yonenaga, Ichiro [Institute for Materials Research, Tohoku University (Japan)

    2006-03-31

    We present studies of muonium behaviour in bulk, Czochralski-grown Si{sub 1-} {sub x} Ge {sub x} alloy material, focusing in particular on the hyperfine parameter of the tetrahedral muonium species. In contrast to the bond-centred species, the hyperfine parameter of the tetrahedral-site muonium centre (Mu{sub T}) appears to vary non-linearly with alloy composition. The temperature dependence of the Mu{sub T} hyperfine parameter observed in low-Ge alloy material is compared with that seen in pure Si, and previous models of the Mu{sub T} behaviour in Si are discussed in the light of results from Si{sub 1-} {sub x} Ge {sub x} alloys.

  19. Hyperfine-induced electric dipole contributions to the electric octupole and magnetic quadrupole atomic clock transitions

    CERN Document Server

    Dzuba, V A

    2016-01-01

    Hyperfine-induced electric dipole contributions may significantly increase probabilities of otherwise very weak electric octupole and magnetic quadrupole atomic clock transitions (e.g. transitions between $s$ and $f$ electron orbitals). These transitions can be used for exceptionally accurate atomic clocks, quantum information processing and search for dark matter. They are very sensitive to new physics beyond the Standard Model, such as temporal variation of the fine structure constant, the Lorentz invariance and Einstein equivalence principle violation. We formulate conditions under which the hyperfine-induced electric dipole contribution dominates. Due to the hyperfine quenching the electric octupole clock transition in $^{173}$Yb$^+$ is two orders of magnitude stronger than that in currently used $^{171}$Yb$^+$. Some enhancement is found in $^{143}$Nd$^{13+}$, $^{149}$Pm$^{14+}$, $^{147}$Sm$^{14+}$, and $^{147}$Sm$^{15+}$ ions.

  20. Hyperfine-frequency shifts of alkali-metal atoms during long-range collisions

    CERN Document Server

    McGuyer, B H

    2013-01-01

    Collisions with chemically inert atoms or molecules change the hyperfine coupling of an alkali-metal atom through the hyperfine-shift interaction. This interaction is responsible for the pressure shifts of the microwave resonances of alkali-metal atoms in buffer gases, is an important spin interaction in alkali-metal--noble-gas van der Waals molecules, and is anticipated to enable the magnetoassociation of ultracold molecules such as RbSr. An improved estimate is presented for the long-range asymptote of this interaction for Na, K, Rb, and Cs. To test the results, the change in hyperfine coupling due to a static electric field is estimated and reasonable agreement is found.

  1. Hyperfine electric parameters calculation in Si samples implanted with {sup 57}Mn→{sup 57}Fe

    Energy Technology Data Exchange (ETDEWEB)

    Abreu, Y., E-mail: yabreu@ceaden.edu.cu [Centro de Aplicaciones Tecnológicas y Desarrollo Nuclear (CEADEN), Calle 30 No. 502 e/5ta y 7ma Ave., 11300 Miramar, Playa, La Habana (Cuba); Cruz, C.M.; Piñera, I.; Leyva, A.; Cabal, A.E. [Centro de Aplicaciones Tecnológicas y Desarrollo Nuclear (CEADEN), Calle 30 No. 502 e/5ta y 7ma Ave., 11300 Miramar, Playa, La Habana (Cuba); Van Espen, P. [Departement Chemie, Universiteit Antwerpen, Middelheimcampus, G.V.130, Groenenborgerlaan 171, 2020 Antwerpen (Belgium); Van Remortel, N. [Departement Fysica, Universiteit Antwerpen, Middelheimcampus, G.U.236, Groenenborgerlaan 171, 2020 Antwerpen (Belgium)

    2014-07-15

    Nowadays the electronic structure calculations allow the study of complex systems determining the hyperfine parameters measured at a probe atom, including the presence of crystalline defects. The hyperfine electric parameters have been measured by Mössbauer spectroscopy in silicon materials implanted with {sup 57}Mn→{sup 57}Fe ions, observing four main contributions to the spectra. Nevertheless, some ambiguities still remain in the {sup 57}Fe Mössbauer spectra interpretation in this case, regarding the damage configurations and its evolution with annealing. In the present work several implantation environments are evaluated and the {sup 57}Fe hyperfine parameters are calculated. The observed correlation among the studied local environments and the experimental observations is presented, and a tentative microscopic description of the behavior and thermal evolution of the characteristic defects local environments of the probe atoms concerning the location of vacancies and interstitial Si in the neighborhood of {sup 57}Fe ions in substitutional and interstitial sites is proposed.

  2. Solar water splitting: efficiency discussion

    OpenAIRE

    Juodkazyte, Jurga; Seniutinas, Gediminas; Sebeka, Benjaminas; Savickaja, Irena; Malinauskas, Tadas; Badokas, Kazimieras; Juodkazis, Kestutis; Juodkazis, Saulius

    2016-01-01

    The current state of the art in direct water splitting in photo-electrochemical cells (PECs) is presented together with: (i) a case study of water splitting using a simple solar cell with the most efficient water splitting electrodes and (ii) a detailed mechanism analysis. Detailed analysis of the energy balance and efficiency of solar hydrogen production are presented. The role of hydrogen peroxide formation as an intermediate in oxygen evolution reaction is newly revealed and explains why a...

  3. Split Quasi-adequate Semigroups

    Institute of Scientific and Technical Information of China (English)

    Xiao Jiang GUO; Ting Ting PENG

    2012-01-01

    The so-called split IC quasi-adequate semigroups are in the class of idempotent-connected quasi-adequate semigroups.It is proved that an IC quasi-adequate semigroup is split if and only if it has an adequate transversal.The structure of such semigroup whose band of idempotents is regular will be particularly investigated.Our obtained results enrich those results given by McAlister and Blyth on split orthodox semigroups.

  4. Comet LINEAR Splits Further

    Science.gov (United States)

    2001-05-01

    Third Nucleus Observed with the VLT Summary New images from the VLT show that one of the two nuclei of Comet LINEAR (C/2001 A2), now about 100 million km from the Earth, has just split into at least two pieces . The three fragments are now moving through space in nearly parallel orbits while they slowly drift apart. This comet will pass through its perihelion (nearest point to the Sun) on May 25, 2001, at a distance of about 116 million kilometres. It has brightened considerably due to the splitting of its "dirty snowball" nucleus and can now be seen with the unaided eye by observers in the southern hemisphere as a faint object in the southern constellation of Lepus (The Hare). PR Photo 18a/01 : Three nuclei of Comet LINEAR . PR Photo 18b/01 : The break-up of Comet LINEAR (false-colour). Comet LINEAR splits and brightens ESO PR Photo 18a/01 ESO PR Photo 18a/01 [Preview - JPEG: 400 x 438 pix - 55k] [Normal - JPEG: 800 x 875 pix - 136k] ESO PR Photo 18b/01 ESO PR Photo 18b/01 [Preview - JPEG: 367 x 400 pix - 112k] [Normal - JPEG: 734 x 800 pix - 272k] Caption : ESO PR Photo 18a/01 shows the three nuclei of Comet LINEAR (C/2001 A2). It is a reproduction of a 1-min exposure in red light, obtained in the early evening of May 16, 2001, with the 8.2-m VLT YEPUN (UT4) telescope at Paranal. ESO PR Photo 18b/01 shows the same image, but in a false-colour rendering for more clarity. The cometary fragment "B" (right) has split into "B1" and "B2" (separation about 1 arcsec, or 500 km) while fragment "A" (upper left) is considerably fainter. Technical information about these photos is available below. Comet LINEAR was discovered on January 3, 2001, and designated by the International Astronomical Union (IAU) as C/2001 A2 (see IAU Circular 7564 [1]). Six weeks ago, it was suddenly observed to brighten (IAUC 7605 [1]). Amateurs all over the world saw the comparatively faint comet reaching naked-eye magnitude and soon thereafter, observations with professional telescopes indicated

  5. Hyperfine interactions in the itinerant system UFeGa{sub 5}

    Energy Technology Data Exchange (ETDEWEB)

    Kambe, S. [Advanced Science Research Center, Japan Atomic Energy Agency, Tokai-mura, Shirakata-shirane-2-4, Ibaraki 319-1195 (Japan)], E-mail: kambe.shinsaku@jaea.go.jp; Sakai, H.; Tokunaga, Y.; Chudo, H.; Yasuoka, H.; Matsuda, T.D.; Haga, Y.; Ikeda, S.; Nakamura, A.; Yamamoto, E. [Advanced Science Research Center, Japan Atomic Energy Agency, Tokai-mura, Shirakata-shirane-2-4, Ibaraki 319-1195 (Japan); Aoki, D.; Homma, Y.; Shiokawa, Y. [Institute for Materials Research, Tohoku University, Oarai, Ibaraki 311-1313 (Japan); Onuki, Y. [Graduate School of Science, Osaka University, Toyonaka, Osaka 560-0043 (Japan)

    2009-03-15

    We report {sup 69}Ga NMR measurements on the itinerant compound UFeGa{sub 5} using a single crystal sample. Hyperfine coupling constants at both the Ga(1) and Ga(2) sites are determined for H-parallel a and c-axes based on Knight shift versus susceptibility plots. The T-dependence of the spin-lattice relaxation time (T{sub 1}) has been determined at both sites for H-parallel a and c-axes. From these quantities, the magnetic fluctuations are estimated for both axes. The complex nature of the hyperfine interactions is discussed.

  6. Spin dynamics and hyperfine interaction in InAs semiconductor quantum dots

    Energy Technology Data Exchange (ETDEWEB)

    Eble, B.; Krebs, O.; Voisin, P.; Lemaitre, A.; Kudelski, A. [CNRS - Laboratoire de Photonique et Nanostructures, Route de Nozay, 91460 Marcoussis (France); Braun, P.F.; Lombez, L.; Marie, X.; Urbaszek, B.; Amand, T.; Lagarde, D.; Renucci, P. [Laboratoire de Nanophysique Magnetisme et Optoelectronique, INSA, 31077 Toulouse Cedex 4 (France); Kowalik, K. [CNRS - Laboratoire de Photonique et Nanostructures, Route de Nozay, 91460 Marcoussis (France); Institute of Experimental Physics, Warsaw University, Hoza 69, 00-681 Warsaw (Poland); Kalevich, V.K.; Kavokin, K.V. [Ioffe Institute, Politekhnicheskaya 26, St-Petersburg 194021 (Russian Federation)

    2006-08-15

    We present a detailed study of the hyperfine interaction between carrier and nuclear spins in InAs semiconductor quantum dots. Time resolved measurements on excitons in positively charged quantum dots show the electron spin relaxation due to random fluctuations of the spin orientation of the nuclei in the quantum dot. A complimentary aspect of the hyperfine interaction can be uncovered in single dot continuous wave photoluminescence experiments in a weak magnetic field, namely the Overhauser shift due to the dynamic polarisation of the nuclei following excitation with circularly polarised light. (copyright 2006 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

  7. Production of Nuclear Polarization of Na Isotopes at ISAC/TRIUMF and its Hyperfine Interaction

    Energy Technology Data Exchange (ETDEWEB)

    Minamisono, K., E-mail: minamiso@nscl.msu.edu [NSCL/MSU (United States); Matsuta, K.; Minamisono, T. [Osaka University, Department of Physics (Japan); Levy, C. D. P. [TRIUMF (Canada); Nagatomo, T.; Ogura, M. [Osaka University, Department of Physics (Japan); Sumikama, T. [RIKEN (Japan); Behr, J. A.; Jackson, K. P. [TRIUMF (Canada); Fujiwara, H.; Mihara, M.; Fukuda, M. [Osaka University, Department of Physics (Japan)

    2004-12-15

    Hyperfine interactions of Na isotopes in single crystals have been studied using highly nuclear polarized {sup 20,21,26,27,28}Na beams provided by ISAC/TRIUMF. The degree of polarization kept in the crystals, the spin-lattice relaxation times, the electric quadrupole coupling constants and the initial distribution of the populations were measured. Such knowledge is indispensable for the application of the hyperfine interactions in the study of precision measurements such as the nuclear structure through nuclear moments and the fundamental symmetries.

  8. Measurement of hyperfine structure in the $\\rm D_1$ line of $^{87}$Rb

    CERN Document Server

    Datar, Durgesh; Ananthamurthy, Sharath; Natarajan, Vasant

    2016-01-01

    This work reports a new measurement of the hyperfine structure constant of the $\\rm D_1 $ line in $ \\rm ^{87}Rb $ through precision laser spectroscopy. In a departure from methods that rely on locking the laser on the transitions of interest, the technique reported here relies on scanning around the transition. This is carried out so as to overcome potential frequency shifts caused by various noise sources including electronic noise and thermal fluctuations. The value of the hyperfine constant reported here is $ A = 408.29(25) $ MHz, which is in variance from an earlier value reported from our lab but is consistent with other recent measurements.

  9. Study of coupled-cluster correlations on electromagnetic transitions and hyperfine structure constants of W VI

    CERN Document Server

    Bhowmik, Anal; Roy, Sourav; Majumder, Sonjoy

    2016-01-01

    This work presents precise calculations of important electromagnetic transition amplitudes along with detail of their many-body correlations using relativistic coupled cluster method. Studies of hyperfine interaction constants, useful for plasma diagnostic, with this correlation exhaustive many-body approach are another important area of this work. The calculated oscillator strengths of allowed transitions, amplitudes of forbidden transitions and lifetimes are compared with the other theoretical results wherever available and they show a good agreement. Hyperfine constants of ?different isotopes of W VI, presented in this paper will be helpful to get accurate picture of abundances of this element in different astronomical bodies.

  10. Temperature-dependent hyperfine interactions at {sup 111}Cd-C complex in germanium

    Energy Technology Data Exchange (ETDEWEB)

    Mola, Genene Tessema [University of Kwazulu-Natal, School Chemistry and Physics, Pietermaritzburg Campus, Private Bag X01, Scottsville (South Africa)

    2013-09-15

    The temperature dependent nuclear hyperfine interaction of {sup 111}Cd-carbon complex in germanium has been studied using the perturbed {gamma}-{gamma} angular correlation (PAC) method. The parameters of the hyperfine interaction representing substitutional carbon-cadmium complex in germanium ({nu} {sub Q1}=207(1) MHz ({eta}=0.16)) shows dependence on temperature. The formation and thermal stability of the complex has been reported by the same author earlier. It was found in this study that the quadrupole coupling constant of the interaction increases at sample temperature below 293 K. The results are encouraging toward better understanding of the complex in the host matrix. (orig.)

  11. Thermally induced photon splitting

    CERN Document Server

    Elmfors, P; Elmfors, Per; Skagerstam, Bo-Sture

    1998-01-01

    We calculate thermal corrections to the non-linear QED effective action for low-energy photon interactions in a background electromagnetic field. The high-temperature expansion shows that at $T \\gg m$ the vacuum contribution is exactly cancelled to all orders in the external field except for a non-trivial two-point function contribution. The high-temperature expansion derived reveals a remarkable cancellation of infrared sensitive contributions. As a result photon-splitting in the presence of a magnetic field is suppressed in the presence of an electron-positron QED-plasma at very high temperatures. In a cold and dense plasma a similar suppression takes place. At the same time Compton scattering dominates for weak fields and the suppression is rarely important in physical situations.

  12. Leptogenesis from split fermions

    Energy Technology Data Exchange (ETDEWEB)

    Nagatani, Yukinori; Perez, Gilad

    2004-01-11

    We present a new type of leptogenesis mechanism based on a two-scalar split-fermions framework. At high temperatures the bulk scalar vacuum expectation values (VEVs) vanish and lepton number is strongly violated. Below some temperature, T{sub c}, the scalars develop extra dimension dependent VEVs. This transition is assumed to proceed via a first order phase transition. In the broken phase the fermions are localized and lepton number violation is negligible. The lepton-bulk scalar Yukawa couplings contain sizable CP phases which induce lepton production near the interface between the two phases. We provide a qualitative estimation of the resultant baryon asymmetry which agrees with current observation. The neutrino flavor parameters are accounted for by the above model with an additional approximate U(1) symmetry.

  13. Modified split level lid resection in ptosis

    Directory of Open Access Journals (Sweden)

    Bethria S

    1990-01-01

    Full Text Available 10 patients of congenital simple ptosis having 3 to 5 mm of ptosis with variable levator action were operated. All the patients showed a good response of lid lift after instillation of phenyl ephrine drops showing the activity of Muller′s muscle. With this technique the lagophthalmos was minimal and good lid folds were formed in all cases. The skin muscle lamina was not excised and was utilized for formation of lid folds which were equal in depth and dynamic in nature. However, the lid lag which is an unavoidable complication of any ptosis surgery was present in the present technique also.

  14. Calculations of hyperfine coupling constant of copper(II) in aqueous environment. Finite temperature molecular dynamics and relativistic effects.

    Science.gov (United States)

    Malček, Michal; Bučinský, Lukáš; Valko, Marián; Biskupič, Stanislav

    2015-09-01

    The presented paper is focused on the calculation of hyperfine coupling constants (HFCC) of Cu (2+) ion in water environment. To simulate the conditions of the electron paramagnetic resonance (EPR) experiment in aqueous phase, molecular dynamics using the density functional theory (DFT) was employed. In total three different functionals (BLYP, B3LYP, M06) were employed for studying their suitability in describing coordination of Cu (2+) by water molecules. The system of our interest was composed of one Cu (2+) cation surrounded by a selected number (between thirty and fifty) of water molecules. Besides the non-relativistic HFCCs (Fermi contact terms) of Cu (2+) also the four-component relativistic HFCC calculations are presented. The importance of the proper evaluation of HFCCs, the inclusion of spin-orbit term, for Cu (2+) containing systems (Neese, J. Chem. Phys. 118, 3939 2003; Almeida et al., Chem. Phys. 332, 176 2007) is confirmed at the relativistic four-component level of theory.

  15. Hyperfine-induced valley mixing and the spin-valley blockade in carbon-based quantum dots

    Energy Technology Data Exchange (ETDEWEB)

    Palyi, Andras; Burkard, Guido [Department of Physics, University Konstanz (Germany)

    2010-07-01

    Hyperfine interaction (HFI) in carbon nanotube and graphene quantum dots is due to the presence of {sup 13}C atoms. We theoretically show that in these structures the short-range nature of the HFI gives rise to a coupling between the valley degree of freedom of the electron and the nuclear spin, in addition to the usual electron spin-nuclear spin coupling. We predict that this property of the HFI affects the Pauli blockade transport in carbon-based double quantum dots. In particular, we show that transport is blocked only if both the spin and the valley degeneracies of the quantum dot levels are lifted, e.g., by an appropriately oriented magnetic field. The blockade is caused by four ''supertriplet'' states in the (1,1) charge configuration.

  16. The effect of hyperfine interactions on ultracold molecular collisions: NH(^3Sigma^-) with Mg(^1S) in magnetic fields

    CERN Document Server

    González-Martínez, Maykel L

    2011-01-01

    We investigate the effect of hyperfine interactions on ultracold molecular collisions in magnetic fields, using ^{24}Mg(^1S) + ^{14}NH(^3Sigma^-) as a prototype system. We explore the energy and magnetic field dependence of the cross sections, comparing the results with previous calculations that neglected hyperfine interactions (Phys. Rev. Lett. 103, 183201 (2009)). The main effect of hyperfine interactions for spin relaxation cross sections is that the kinetic energy release of the dominant outgoing channels does not reduce to zero at low fields. This results in reduced centrifugal suppression on the cross sections and increased inelastic cross sections at low energy and low field. We also analyze state-to-state cross sections, for various initial states, and show that hyperfine interactions introduce additional mechanisms for spin relaxation. In particular, there are hyperfine-mediated collisions to outgoing channels that are not centrifugally suppressed. However, for Mg+NH these unsuppressed channels make...

  17. Improving the calculation of electron paramagnetic resonance hyperfine coupling tensors for d-block metals

    DEFF Research Database (Denmark)

    Hedegård, Erik Donovan; Kongsted, Jacob; Sauer, Stephan P. A.

    2012-01-01

    and obtained a set of basis functions for the elements Sc–Zn, which were saturated with respect to both the Fermi contact and spin-dipolar components of the hyperfine coupling tensor [Hedeg°ard et al., J. Chem. Theory Comput., 2011, 7, pp. 4077-4087]. Furthermore, a contraction scheme was proposed leading...

  18. Magnetic hyperfine interaction studies of isolated Ni impurities in Pd and Pd-Pt alloys

    Science.gov (United States)

    Müller, W.; Bertschat, H. H.; Haas, H.; Spellmeyer, B.; Zeitz, W.-D.

    1989-10-01

    The magnetic hyperfine fields at isolated Ni impurities in Pd and Pd-Pt alloys were studied with the perturbed-angular-distribution (PAD) method by measuring the temperature, magnetic field, and concentration dependence of the nuclear-spin Larmor precession of isomeric states in 63Ni. The recoil-implanted Ni nuclei, as products of heavy-ion nuclear reactions, are present in extreme dilution (Pd-Pt alloys a considerable positive shift remains even at 30 at. % Pt content. The variation of the shift with Pt concentration and temperature reflects the variation of the Pd-Pt alloy susceptibility. The different contributions to the hyperfine field could be differentiated by comparing the Knight shift for Ni in Pd with its susceptibility contribution obtained from extrapolated susceptibility measurements in dilute Pd-Ni alloys. The negative core-polarization field of the impurity spin moment is compensated for by a transferred hyperfine field correlated with the host polarization in the neighborhood of the impurity. The remaining positive hyperfine field is due to a weak orbital moment of 0.3μB at the impurity site. The values obtained for the different contributions are compared with results of the Korringa-Kohn-Rostoker-coherent-potential-approximation calculations for concentrated Pd-Ni alloys extrapolated to the dilute limit.

  19. First-principles calculations of Moessbauer hyperfine parameters for solids and large molecules

    Energy Technology Data Exchange (ETDEWEB)

    Guenzburger, Diana [Centro Brasileiro de Pesquisas Fisicas (CBPF), Rio de Janeiro, RJ (Brazil); Ellis, D.E. [Northwestern Univ., Evanston, IL (United States). Dept. of Physics; Zeng, Z. [Academia Sinica, Hefei, AH (China). Inst. of Solid-State Physics

    1997-10-01

    Electronic structure calculations based on Density Functional theory were performed for solids and large molecules. The solids were represented by clusters of 60-100 atoms embedded in the potential of the external crystal. Magnetic moments and Moessbauer hyperfine parameters were derived. (author) 22 refs., 8 figs., 1 tab.

  20. Observation of HCN hyperfine line anomalies towards low- and high-mass star-forming cores

    CERN Document Server

    Loughnane, R M; Thompson, M A; Lo, N; O'Dwyer, B; Cunningham, M R; 10.1111/j.1365-2966.2011.20121.x

    2013-01-01

    HCN is becoming a popular choice of molecule for studying star formation in both low- and high-mass regions and for other astrophysical sources from comets to high-redshift galaxies. However, a major and often overlooked difficulty with HCN is that it can exhibit non-local thermodynamic equilibrium (non-LTE) behaviour in its hyperfine line structure. Individual hyperfine lines can be strongly boosted or suppressed. In low-mass star-forming cloud observations, this could possibly lead to large errors in the calculation of opacity and excitation temperature, while in massive star-forming clouds, where the hyperfine lines are blended due to turbulent broadening, errors will arise in infall measurements that are based on the separation of the peaks in a self-absorbed profile. The underlying line shape cannot be known for certain if hyperfine anomalies are present. We present a first observational investigation of these anomalies across a range of conditions and transitions by carrying out a survey of low-mass sta...

  1. Magnetic hyperfine field at a Cd impurity diluted in RCo{sub 2} at finite temperatures

    Energy Technology Data Exchange (ETDEWEB)

    Oliveira, A.L. de, E-mail: alexandre.oliveira@ifrj.edu.br [Instituto Federal de Educação, Ciência e Tecnologia do Rio de Janeiro, Campus Nilópolis – RJ (Brazil); Chaves, C.M., E-mail: cmch@cbpf.br [Centro Brasileiro de Pesquisas Físicas, Rio de Janeiro (Brazil); Oliveira, N.A. de [Instituto de Física Armando Dias Tavares, Universidade do Estado do Rio de Janeiro, Rio de Janeiro (Brazil); Troper, A. [Centro Brasileiro de Pesquisas Físicas, Rio de Janeiro (Brazil)

    2015-06-15

    The local magnetic moments and the magnetic hyperfine fields at an s–p Cd impurity diluted in inter-metallic Laves phase compounds RCo{sub 2} (R=Gd, Tb) at finite temperatures are calculated. For other rare earth elements (light or heavy) the pure compounds display a magnetic first order transition and are not describable by our formalism. The host has two coupled lattices (R and Co) both having itinerant d electrons but only the rare earth lattice has localized f electrons. They all contribute to the magnetization of the host and also to the local moment and to the magnetic hyperfine field at the impurity. The investigation of magnetic hyperfine field in these materials then provides valuable information on the d-itinerant electrons and also on the localized (4f) magnetic moments. For the d–d electronic interaction we use the Hubbard–Stratonovich identity thus allowing the employment of functional integral in the static saddle point approximation. Our model reproduces quite well the experimental data. - Highlights: • A functional integral method in the static limit, producing site disorder, is used. • The site disorder is treated with the coherent potential approximation (CPA) • A Friedel sum rule gives a self-consistency condition for the impurity energy. • The experimental curve of hyperfine fields×temperature is very well reproduced.

  2. Hyperfine field and magnetic structure in the B phase of CeCoIn5

    Energy Technology Data Exchange (ETDEWEB)

    Graf, Matthias J [Los Alamos National Laboratory; Curro, Nicholas J [UNIV OF CAL; Young, Ben - Li [NATIONAL CHIAO UNIV; Urbano, Ricardo R [FL STATE UNIV

    2009-01-01

    We re-analyze Nuclear Magnetic Resonance (NMR) spectra observed at low temperatures and high magnetic fields in the field-induced B-phase of CeCoIn{sub 5}. The NMR spectra are consistent with incommensurate antiferromagnetic order of the Ce magnetic moments. However, we find that the spectra of the In(2) sites depend critically on the direction of the ordered moments, the ordering wavevector and the symmetry of the hyperfine coupling to the Ce spins. Assuming isotropic hyperfine coupling, the NMR spectra observed for H {parallel} [100] are consistent with magnetic order with wavevector Q = {pi}(1+{delta}/a, 1/a, 1/c) and Ce moments ordered antiferromagnetically along the [100] direction in real space. If the hyperfine coupling has dipolar symmetry, then the NMR spectra require Ce moments along the [001] direction. The dipolar scenario is also consistent with recent neutron scattering measurements that find an ordered moment of 0.15{micro}{sub B} along [001] and Q{sub n} = {pi}(1+{delta}/a, 1+{delta}c, 1/c) with incommensuration {delta} = 0.12 for field H {parallel} [1{bar 1}0]. Using these parameters, we find that the hyperfine field is consistent with both experiments. We speculate that the B phase of CeCoIn{sub 5} represents an intrinsic phase of modulated superconductivity and antiferromagnetism that can only emerge in a highly clean system.

  3. Theoretical investigation of the hyperfine structure in spatially and spin degenerate electronic states

    Directory of Open Access Journals (Sweden)

    JELENA RADIC-PERIC

    2005-03-01

    Full Text Available The present paper reviews the results of ab initio studies on the magnetic hyperfine structure in spectra of spatially and spin degenerate electronic states of triatomic and tetra-atomic molecules. The main goal of the present paper is to show that such theoretical investigations can be used to reliably reproduce, explain and predict the results of the corresponding measurements.

  4. Split brain: divided perception but undivided consciousness.

    Science.gov (United States)

    Pinto, Yair; Neville, David A; Otten, Marte; Corballis, Paul M; Lamme, Victor A F; de Haan, Edward H F; Foschi, Nicoletta; Fabri, Mara

    2017-01-24

    In extensive studies with two split-brain patients we replicate the standard finding that stimuli cannot be compared across visual half-fields, indicating that each hemisphere processes information independently of the other. Yet, crucially, we show that the canonical textbook findings that a split-brain patient can only respond to stimuli in the left visual half-field with the left hand, and to stimuli in the right visual half-field with the right hand and verbally, are not universally true. Across a wide variety of tasks, split-brain patients with a complete and radiologically confirmed transection of the corpus callosum showed full awareness of presence, and well above chance-level recognition of location, orientation and identity of stimuli throughout the entire visual field, irrespective of response type (left hand, right hand, or verbally). Crucially, we used confidence ratings to assess conscious awareness. This revealed that also on high confidence trials, indicative of conscious perception, response type did not affect performance. These findings suggest that severing the cortical connections between hemispheres splits visual perception, but does not create two independent conscious perceivers within one brain.

  5. Split-ball resonator

    CERN Document Server

    Kuznetsov, Arseniy I; Fu, Yuan Hsing; Viswanathan, Vignesh; Rahmani, Mohsen; Valuckas, Vytautas; Kivshar, Yuri; Pickard, Daniel S; Lukiyanchuk, Boris

    2014-01-01

    We introduce a new concept of split-ball resonator and demonstrate a strong omnidirectional magnetic dipole response for both gold and silver spherical plasmonic nanoparticles with nanometer-scale cuts. Tunability of the magnetic dipole resonance throughout the visible spectral range is demonstrated by a change of the depth and width of the nanoscale cut. We realize this novel concept experimentally by employing the laser-induced transfer method to produce near-perfect spheres and helium ion beam milling to make cuts with the nanometer resolution. Due to high quality of the spherical particle shape, governed by strong surface tension forces during the laser transfer process, and the clean, straight side walls of the cut made by helium ion milling, magnetic resonance is observed at 600 nm in gold and at 565 nm in silver nanoparticles. Structuring arbitrary features on the surface of ideal spherical resonators with nanoscale dimensions provides new ways of engineering hybrid resonant modes and ultra-high near-f...

  6. Hidden sector hydrogen as dark matter: Small-scale structure formation predictions and the importance of hyperfine interactions

    Science.gov (United States)

    Boddy, Kimberly K.; Kaplinghat, Manoj; Kwa, Anna; Peter, Annika H. G.

    2016-12-01

    We study the atomic physics and the astrophysical implications of a model in which the dark matter is the analog of hydrogen in a secluded sector. The self-interactions between dark matter particles include both elastic scatterings as well as inelastic processes due to a hyperfine transition. The self-interaction cross sections are computed by numerically solving the coupled Schrödinger equations for this system. We show that these self-interactions exhibit the right velocity dependence to explain the low dark matter density cores seen in small galaxies while being consistent with all constraints from observations of clusters of galaxies. For a viable solution, the dark hydrogen mass has to be in the 10-100 GeV range and the dark fine-structure constant has to be larger than 0.01. This range of model parameters requires the existence of a dark matter-antimatter asymmetry in the early universe to set the relic abundance of dark matter. For this range of parameters, we show that significant cooling losses may occur due to inelastic excitations to the hyperfine state and subsequent decays, with implications for the evolution of low-mass halos and the early growth of supermassive black holes. Cooling from excitations to higher n levels of dark hydrogen and subsequent decays is possible at the cluster scale, with a strong dependence on halo mass. Finally, we show that the minimum halo mass is in the range of 1 03.5 to 1 07M⊙ for the viable regions of parameter space, significantly larger than the typical predictions for weakly interacting dark matter models. This pattern of observables in cosmological structure formation is unique to this model, making it possible to rule in or rule out hidden sector hydrogen as a viable dark matter model.

  7. Doping effects on the structural, magnetic, and hyperfine properties of Gd-doped SnO{sub 2} nanoparticles

    Energy Technology Data Exchange (ETDEWEB)

    Coelho-Júnior, H.; Aquino, J. C. R.; Aragón, F. H. [Universidade de Brasília, Núcleo de Física Aplicada, Instituto de Física (Brazil); Hidalgo, P. [Universidade de Brasília, Faculdade Gama-FGA, Setor Central Gama (Brazil); Cohen, R.; Nagamine, L. C. C. M. [Universidade de São Paulo, Instituto de Física (Brazil); Coaquira, J. A. H., E-mail: coaquira@unb.br; Silva, S. W. da [Universidade de Brasília, Núcleo de Física Aplicada, Instituto de Física (Brazil); Brito, H. F. [Universidade de São Paulo, Instituto de Química (Brazil)

    2014-12-15

    In this work we present the study of the structural, magnetic, and hyperfine properties of Gd-doped SnO{sub 2} nanoparticles synthesized by a polymer precursor method. The X-ray diffraction data analysis shows the formation of the rutile-type structure in all samples with Gd content from 1.0 to 10.0 mol%. The mean crystallite size is ∼11 nm for the 1.0 mol% Gd-doped samples and it shows a decreasing tendency as the Gd content is increased. The analysis of magnetic measurements indicates the coexistence of ferromagnetic and paramagnetic phases for the 1.0 mol% Gd-doped sample; however, above that content, only a paramagnetic phase is observed. The ferromagnetic phase observed in the 1.0 mol% Gd-doped sample has been assigned to the presence of bound magnetic polarons which overlap to create a spin-split impurity band. Room-temperature {sup 119}Sn Mössbauer measurements reveal the occurrence of strong electric quadrupole interactions. It has been determined that the absence of magnetic interactions even for 1.0 mol% Gd-doped sample has been related to the weak magnetic field associated to the exchange interaction between magnetic ions and the donor impurity band. The broad distribution of electric quadrupole interactions are attributed to the several non-equivalent surroundings of Sn{sup 4+} ions provoked by the entrance of Gd{sup 3+} ions and to the likely presence of Sn{sup 2+} ions. The isomer shift seems to be nearly independent of the Gd content for samples with Gd content below 7.5 mol%.

  8. Mössbauer hyperfine parameters of iron species in the course of Geobacter-mediated magnetite mineralization

    Science.gov (United States)

    Li, Yi-Liang; Zhu, San-Yuan; Deng, Kun

    2011-10-01

    Amorphous ferric iron species (ferrihydrite or akaganeite of <5 nm in size) is the only known solid ferric iron oxide that can be reductively transformed by dissimilatory iron-reducing bacteria to magnetite completely. The lepidocrocite crystallite can be transformed into magnetite in the presence of abiotic Fe(II) at elevated pH or biogenic Fe(II) with particular growth conditions. The reduction of lepidocrocite by dissimilatory iron-reducing bacteria has been widely investigated showing varying results. Vali et al. (Proc Natl Acad Sci USA 101:16121-16126, 2004) captured a unique biologically mediated mineralization pathway where the amorphous hydrous ferric oxide transformed to lepidocrocite was followed by the complete reduction of lepidocrocite to single-domain magnetite. Here, we report the 57Fe Mössbauer hyperfine parameters of the time-course samples reported in Vali et al. (Proc Natl Acad Sci USA 101:16121-16126, 2004). Both the quadrupole splittings and linewidths of Fe(III) ions decrease consistently with the change of aqueous Fe(II) and transformations of mineral phases, showing the Fe(II)-mediated gradual regulation of the distorted coordination polyhedrons of Fe3+ during the biomineralization process. The aqueous Fe(II) catalyzes the transformations of Fe(III) minerals but does not enter the mineral structures until the mineralization of magnetite. The simulated abiotic reaction between Fe(II) and lepidocrocite in pH-buffered, anaerobic media shows the simultaneous formation of green rust and its gradual transformation to magnetite plus a small fraction of goethite. We suggested that the dynamics of Fe(II) supply is a critical factor for the mineral transformation in the dissimilatory iron-reducing cultures.

  9. Hyperfine interactions in Ho(Fe{sub 1-x}Co{sub x}){sub 2} compounds at 77 K

    Energy Technology Data Exchange (ETDEWEB)

    Bednarski, M; Pszczola, J; Bodnar, W [Faculty of Physics and Applied Computer Science, AGH University of Science and Technology, A Mickiewicza Avenue 30, 30-059 Krakow (Poland); Stoch, P; Zachariasz, P; Suwalski, J, E-mail: pszczola@agh.edu.p [Institute of Atomic Energy, 05-400 Swierk-Otwock (Poland)

    2011-01-15

    Synthesized, x-ray studied Ho(Fe{sub 1-x}Co{sub x}){sub 2} compounds (x= 0-1) have a pure cubic Fd3m, C15, MgCu{sub 2}-type crystal phase. The unit cell parameter decreases nonlinearly with the composition parameter x. Moessbauer effect spectra collected at 77 K for the Ho(Fe{sub 1-x}Co{sub x}){sub 2} series were composed of a number of locally originated subspectra due to random Fe/Co nearest neighbourhoods. Hyperfine interaction parameters, i.e. the isomer shift, the magnetic hyperfine field and the quadrupole interaction parameter, were determined from the fitting procedure of the spectra for the individual nearest neighbourhoods and also as average values for the sample as bulk. As a result of Fe/Co substitution, Slater-Pauling-type dependences for magnetic hyperfine fields corresponding to both the local area and the sample as bulk were observed. A correlation between the local magnetic hyperfine fields and the average magnetic hyperfine fields was noticed, and this was related to weak and strong ferromagnetism of the transition metal sublattice. The obtained magnetic hyperfine fields were compared to analogous data known for compounds with other rare earths. A numerical formula for describing the magnetic hyperfine field as a function of the composition parameter x and rare earth spin S was proposed.

  10. Semantic Parameters of Split Intransitivity.

    Science.gov (United States)

    Van Valin, Jr., Robert D.

    1990-01-01

    This paper argues that split-intransitive phenomena are better explained in semantic terms. A semantic analysis is carried out in Role and Reference Grammar, which assumes the theory of verb classification proposed in Dowty 1979. (49 references) (JL)

  11. ISR split-field magnet

    CERN Multimedia

    1975-01-01

    The experimental apparatus used at intersection 4 around the Split-Field Magnet by the CERN-Bologna Collaboration (experiment R406). The plastic scintillator telescopes are used for precise pulse-height and time-of-flight measurements.

  12. Split-Plot Designs with Mirror Image Pairs as Subplots

    DEFF Research Database (Denmark)

    Tyssedal, John; Kulahci, Murat; Bisgaard, Soren

    2011-01-01

    In this article we investigate two-level split-plot designs where the sub-plots consist of only two mirror image trials. Assuming third and higher order interactions negligible, we show that these designs divide the estimated effects into two orthogonal sub-spaces, separating sub-plot main effects...... and sub-plot by whole-plot interactions from the rest. Further we show how to construct split-plot designs of projectivity P≥3. We also introduce a new class of split-plot designs with mirror image pairs constructed from non-geometric Plackett–Burman designs. The design properties of such designs are very...

  13. Thermoelectric-induced unitary Cooper pair splitting efficiency

    Energy Technology Data Exchange (ETDEWEB)

    Cao, Zhan; Fang, Tie-Feng [Center for Interdisciplinary Studies and Key Laboratory for Magnetism and Magnetic Materials of the Ministry of Education, Lanzhou University, Lanzhou 730000 (China); Li, Lin [Department of Physics, Southern University of Science and Technology of China, Shenzhen 518005 (China); Luo, Hong-Gang [Center for Interdisciplinary Studies and Key Laboratory for Magnetism and Magnetic Materials of the Ministry of Education, Lanzhou University, Lanzhou 730000 (China); Beijing Computational Science Research Center, Beijing 100084 (China)

    2015-11-23

    Thermoelectric effect is exploited to optimize the Cooper pair splitting efficiency in a Y-shaped junction, which consists of two normal leads coupled to an s-wave superconductor via double noninteracting quantum dots. Here, utilizing temperature difference rather than bias voltage between the two normal leads, and tuning the two dot levels such that the transmittance of elastic cotunneling process is particle-hole symmetric, we find current flowing through the normal leads are totally contributed from the splitting of Cooper pairs emitted from the superconductor. Such a unitary splitting efficiency is significantly better than the efficiencies obtained in experiments so far.

  14. Split NMSSM with electroweak baryogenesis

    OpenAIRE

    Demidov, S.; Gorbunov, D; Kirpichnikov, D.

    2016-01-01

    In light of the Higgs boson discovery and other results of the LHC we re-consider generation of the baryon asymmetry in the split Supersymmetry model with an additional singlet superfield in the Higgs sector (non-minimal split SUSY). We find that successful baryogenesis during the first order electroweak phase transition is possible within a phenomenologically viable part of the model parameter space. We discuss several phenomenological consequences of this scenario, namely, predictions for t...

  15. Sub-Doppler two-photon-excitation Rydberg spectroscopy of atomic xenon: mass-selective studies of isotopic and hyperfine structure

    Science.gov (United States)

    Kono, Mitsuhiko; He, Yabai; Baldwin, Kenneth G. H.; Orr, Brian J.

    2016-03-01

    Mass-selective sub-Doppler two-photon excitation (TPE) spectroscopy is employed to resolve isotopic contributions for transitions to high-energy Rydberg levels of xenon in an atomic beam, using narrowband pulses of coherent ultraviolet light at 205-213 nm generated by nonlinear-optical conversion processes. Previous research (Kono et al 2013 J. Phys. B: At. Mol. Opt. Phys. 46 35401), has determined isotope energy shifts and hyperfine structure for 33 high-energy Rydberg levels of gas-phase xenon and accessed Rydberg levels at TPE energies in the range of 94 100-97 300 cm-1 with unprecedented spectroscopic resolution. The new isotopic-mass-resolved results were obtained by adding a pulsed free-jet atomic-beam source and a mass-selective time-of-flight detector to the apparatus in order to discern individual xenon isotopes and extract previously unresolved spectroscopic information. Resulting isotope energy shifts and hyperfine-coupling parameters are examined with regard to trends in principal quantum number n and in atomic angular-momentum quantum numbers, together with empirical and theoretical precedents for such trends.

  16. Hyperfine structure and lifetime measurements in the 4s2nd 2D3/2 Rydberg sequence of Ga I by time-resolved laser spectroscopy

    Science.gov (United States)

    Liu, Chunqing; Tian, Yanshan; Yu, Qi; Bai, Wanshuang; Wang, Xinghao; Wang, Chong; Dai, Zhenwen

    2016-05-01

    The hyperfine structure (HFS) constants of the 4s2nd 2D3/2 (n=6-18) Rydberg sequence and the 4s26p 2P3/2 level for two isotopes of 69Ga and 71Ga atoms were measured by means of the time-resolved laser-induced fluorescence (TR-LIF) technique and the quantum beat method. The observed hyperfine quantum beat spectra were analyzed and the magnetic-dipole HFS constants A as well as the electric-quadrupole HFS constants B of these levels were obtained by Fourier transform and a program for multiple regression analysis. Also using TR-LIF method radiative lifetimes of the above sequence states were determined at room temperature. The measured lifetime values range from 69 to 2279 ns with uncertainties no more than 10%. To our knowledge, the HFS constants of this Rydberg sequence and the lifetimes of the 4s2nd 2D3/2 (n=10-18) levels are reported for the first time. Good agreement between our results and the previous is achieved.

  17. Hyperfine field distributions in disordered Mn2CoSn and Mn2NiSn Heusler alloys

    Indian Academy of Sciences (India)

    N Lakshmi; Anil Pandey; K Venugopalan

    2002-08-01

    Heusler alloys, Mn2CoSn and Mn2NiSn, were prepared and characterized by X-ray studies. Mössbauer studies using Sn-119 were carried out to investigate the hyperfine fields present at the Sn site in these alloys. The hyperfine field distribution in these alloys as well as X-ray studies point to the chemical disorder present in both alloys. Co-existence of a paramagnetic portion along with the magnetic hyperfine part was observed in Mn2CoSn even at low temperatures, while this was not found in Mn2NiSn spectra. Hyperfine fields at Sn site were calculated using Blandin and Campbell model and compared with the experimental results.

  18. Development of atomic spectroscopy technologies - Hyperfine structure of 2 period atoms using optogalvanic effects

    Energy Technology Data Exchange (ETDEWEB)

    Kwon, Nam Ic [Hankuk University of foreign studies, Seoul (Korea)

    2000-03-01

    The source of anomalous broad linewidth of 3{sup 3}P{sub 1},{sub 2},{sub 3}-3{sup 3}D{sub 2},{sub 3},4(3s') transition was explained. The broad optogalvanic spectrum was consisted of two gaussian peaks of different linewidths, and they are separated by 250 MHz. The Narrow peak, which has linewidth of room temperature, is from oxygen atoms already separated, and the shifted broad peak, which has linewidth corresponding to a temperature of 9000 K, is from weakly bound molecular ions. Obtained hyperfine spectrum of fluorine atom at the expected frequency, was too weak to analyze hyperfine structure constants. Microwave discharge might be necessary for higher density of excited state. 16 refs., 11 figs. (Author)

  19. High resolution isotope shifts and hyperfine structure measurements of tungsten by laser induced fluorescence spectroscopy

    CERN Document Server

    Lee, Jeongwon; Leanhardt, Aaron

    2012-01-01

    Isotope shifts and hyperfine structure of tungsten were studied in the near UV range. We have used laser induced fluorescence spectroscopy on a pulsed supersonic beam to probe the 5D0 -> 5F1 transition at 384.9 nm, 7S3 -> 7P4 transition at 400.9 nm, and 7S3 -> 7P3 transition at 407.4 nm. Three new magnetic hyperfine constants are reported for 7P3,7P4, and 5F1 states. The isotope shifts of the 384.9 nm transition are presented for the first time, and the isotope shifts of 400.9 nm and 407.4 nm transition are measured with an order of magnitude higher precision compared to the previous measurements. As a result, the nuclear parameters lambda and lambda_{rel} are extracted from the isotope shifts with an improved precision.

  20. AB-INITIO SIMULATION OF ELECTRONIC FEATURES OF HYPERFINE RARE EARTH OXIDE FILMS FOR SENSORY NANOSYSTEMS

    Directory of Open Access Journals (Sweden)

    A. V. Gulay

    2014-01-01

    Full Text Available Ab-Initio simulation of electronic features of sensoring nanomaterials based on rare earth oxides has been made by the example of yttrium oxide. The simulation method for thin films of nanometer scale consisted in the simulation of the material layer of the thickness equal to unit crystal cell size has been proposed within the VASP simulation package. The atomic bond breakdown in the crystal along one of the coordinate axes is simulated by the increase of a distance between the atomic layers along this axis up to values at which the value of free energy is stabilized. It has been found that the valence and conductivity bands are not revealed explicitly and the band gap is not formed in the hyperfine rare earth oxide film (at the film thickness close to 1 nm. In fact the hyperfine rare earth oxide film loses dielectric properties which were exhibited clear enough in continuum.

  1. Hyperfine fields in Fe-Ni-X alloys and their application to a study of tempering of 9Ni steel

    Energy Technology Data Exchange (ETDEWEB)

    Fultz, B.; Morris, J.W. Jr.

    1984-12-01

    Hyperfine interactions due to solutes in Fe-Ni-X alloys were systematized, and interpreted with a model of linear response of hyperfine magnetic fields to magnetic moments. The effects of solutes on the /sup 57/Fe hmf were used for chemical analysis of the austenite formed in 9Ni steel during tempering. Diffusion kinetics of the Ni and X solutes were found to play an important role in the formation of the austenite particles.

  2. Cobalt-related impurity centers in diamond: electronic properties and hyperfine parameters

    CERN Document Server

    Larico, R; Machado, W V M; Justo, J F

    2013-01-01

    Cobalt-related impurity centers in diamond have been studied using first principles calculations. We computed the symmetry, formation and transition energies, and hyperfine parameters of cobalt impurities in isolated configurations and in complexes involving vacancies and nitrogen atoms. We found that the Co impurity in a divacant site is energetically favorable and segregates nitrogen atoms in its neighborhood. Our results were discussed in the context of the recently observed Co-related electrically active centers in synthetic diamond.

  3. Hyperfine interactions of {beta}-emitter {sup 12}N in TiO{sub 2}

    Energy Technology Data Exchange (ETDEWEB)

    Maruyama, Yukiko [Osaka Univ., Toyonaka (Japan). Faculty of Science; Izumikawa, Takuji; Tanigaki, Minoru [and others

    1997-03-01

    Hyperfine interactions of {beta}-emitter {sup 12}N (I{sup {pi}} = 1{sup -}, T{sub 1/2} 11ms) in TiO{sub 2} has been studied. A {beta}-NMR spectrum on the polarized {sup 12}N implanted in TiO{sub 2} shows that {sup 12}N are located at two different sites and maintain about 100% of initial polarization. These are the first phenomena observed in ionic crystals. (author)

  4. New precise measurement of muonium hyperfine structure interval at J-PARC

    Energy Technology Data Exchange (ETDEWEB)

    Ueno, Y., E-mail: yueno@radphys4.c.u-tokyo.ac.jp [University of Tokyo, Graduate School of Arts and Sciences (Japan); Aoki, M. [Osaka University, Graduate School of Science (Japan); Fukao, Y. [KEK (Japan); Higashi, Y.; Higuchi, T. [University of Tokyo, Graduate School of Arts and Sciences (Japan); Iinuma, H.; Ikedo, Y. [KEK (Japan); Ishida, K. [RIKEN (Japan); Ito, T. U. [Japan Atomic Energy Agency (Japan); Iwasaki, M. [RIKEN (Japan); Kadono, R. [KEK (Japan); Kamigaito, O. [RIKEN (Japan); Kanda, S. [University of Tokyo, Department of Physics (Japan); Kawall, D. [University of Massachusetts, Amherst, Department of Physics (United States); Kawamura, N.; Koda, A.; Kojima, K. M. [KEK (Japan); Kubo, M. K. [International Christian University, Graduate School of Arts and Science (Japan); Matsuda, Y. [University of Tokyo, Graduate School of Arts and Sciences (Japan); Mibe, T. [KEK (Japan); and others

    2017-11-15

    MuSEUM is an international collaboration aiming at a new precise measurement of the muonium hyperfine structure at J-PARC (Japan Proton Accelerator Research Complex). Utilizing its intense pulsed muon beam, we expect a ten-fold improvement for both measurements at high magnetic field and zero magnetic field. We have developed a sophisticated monitoring system, including a beam profile monitor to measure the 3D distribution of muonium atoms to suppress the systematic uncertainty.

  5. Hyperfine coupling of hole and nuclear spins in symmetric GaAs quantum dots

    OpenAIRE

    Vidal, M.; Durnev, M. V.; Bouet, L.; Amand, T.; Glazov, M. M.; Ivchenko, E. L.; Zhou, P; Wang, G.; Mano, T; Kuroda, T.; Marie, X.; Sakoda, K.; Urbaszek, B.

    2016-01-01

    In self assembled III-V semiconductor quantum dots, valence holes have longer spin coherence times than the conduction electrons, due to their weaker coupling to nuclear spin bath fluctuations. Prolonging hole spin stability relies on a better understanding of the hole to nuclear spin hyperfine coupling which we address both in experiment and theory in the symmetric (111) GaAs/AlGaAs droplet dots. In magnetic fields applied along the growth axis, we create a strong nuclear spin polarization d...

  6. Hyperfine specific heats of PrX 2 ( X = Ir, Pt, Rh, Ru) laves phase compounds

    Science.gov (United States)

    Greidanus, F. J. A. M.; de Jongh, L. J.; Huiskamp, W. J.; Buschow, K. H. J.

    1980-01-01

    Specific heat data below 1 K for the C-15 compounds PrX 2 (X = Ir, Pt, Rh, Ru) reveal Schottky-type anomalies, ascribed to hyperfine interactions. Apparently the 4f-moments are magnetically ordered. The values deduced for these moments are only ≈ 70% of that for J = 4, indicating that the Pr 3+ moment is partially quenched by the crystal field.

  7. Isotope shifts and hyperfine structure of {sup 212-214}Ra{sup +}

    Energy Technology Data Exchange (ETDEWEB)

    Giri, Gouri S.; Sahoo, Bijaya K.; Versolato, Oscar O.; Wansbeek, Lotje W.; Willmann, Lorenz; Wilschut, Hans W.; Jungmann, Klaus; Timmermans, Rob G.E. [Kernfysisch Versneller Instituut, University of Groningen (Netherlands)

    2010-07-01

    The availability of short lived Ra isotopes at the TRI{mu}P facility of the KVI makes the study of atomic structure of these isotopes possible. {sup 212-214}Ra ions are trapped in a buffer-gas filled Paul trap. Isotope shifts and hyperfine structures of {sup 212-214}Ra{sup +} for several transitions were obtained by laser spectroscopy. Ra{sup +} is of particular interest for a most precise measurement of Atomic Parity Violation (APV), currently underway in our group. Such a measurement will provide a stringent test of the Standard Model of particle physics. However, the interpretation of APV measurements require the determination of the weak matrix elements to better than 1% accuracy in order to extract the weak charge (Weinberg angle). Currently, our calculations are accurate to some 3%. We therefore plan to exploit the fact that radium has a wide range of isotopes by looking at the ratio E1APV/ E1'APV for two -or more- isotopes, and thus canceling atomic uncertainties. Here, nuclear structure effects start to play a role. The extracted isotope shifts and hyperfine interactions provide indispensable information. In addition, the measured hyperfine structure of {sup 213}Ra{sup +} is of particular interest for the proposed Radium single ion clock.

  8. Investigation of hyperfine interactions in DNA nitrogenous bases using perturbed angular correlation spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Silva, Andreia dos Santos; Carbonari, Artur Wilson; Lapolli, Andre Luis; Saxena, Rajendra Narain [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil); Saitovitch, Henrique, E-mail: asilva@usp.br [Centro Brasileiro de Pesquisas Fisicas (CBPF), Rio de Janeiro, RJ (Brazil)

    2013-07-01

    Perturbed γγ angular correlations (PAC) spectroscopy has been used to study the DNA nitrogenous bases (adenine, cytosine, guanine, thymine), using {sup 111}In→{sup 111}Cd and {sup 111m}Cd→{sup 111}Cd probe nuclei. One of the advantages of applying PAC technique to biological molecules is that the experiments can be carried out on molecules in aqueous solution [1], approaching the function of molecules under conditions that are close to in vivo conditions. The measurements were carried out for DNA nitrogenous bases molecules at 295 K and 77 K in order to investigate dynamic and static hyperfine interactions, respectively. The interpretation of the results was based on the measurements of dynamic interaction characterized by the decay constant from which valuable information on the macroscopic behavior of the molecules was obtained [2; 3]. On the other hand, PAC measurements at low temperature showed interaction frequency (ν{sub Q}), asymmetry parameter (η) and the distribution of the quadrupole frequency (δ). These parameters provide a local microscopic description of the chemical environment in the neighborhood of the probe nuclei. Results showed differences in the hyperfine interactions of probe nuclei bound to the studied biomolecules. Such differences were observed by variations in the hyperfine parameters, which depended on the type of biomolecule and the results also showed that the probe nuclei bounded at the molecules in some cases and at others did not. (author)

  9. Analysis of the competition between forbidden and hyperfine-induced transitions in Ne-like ions

    Science.gov (United States)

    Andersson, Martin; Grumer, Jon; Brage, Tomas; Zou, Yaming; Hutton, Roger

    2016-03-01

    In this work we investigate the decay of the |2 p53 s P30> state in neon-like ions along the isoelectronic sequence ranging from Z =10 to Z =35 . In the absence of a nuclear spin, the magnetic dipole transition to |2 p53 s P31> is the dominating decay channel. However, for isotopes with a nuclear spin, the interaction between the nuclear magnetic dipole moment and the electronic field introduces a mixing of |2 p53 s P31> and |P11> into the |P30> state, which in turn opens up a competing hyperfine-induced electric dipole decay channel to the ground state. This hyperfine-induced transition channel clearly dominates over the magnetic dipole channel for the neutral end of the isoelectronic sequence, when present. We give values for the rates of both these competing channels and discuss how the introduction of the hyperfine-induced transition channel could have a dramatic influence on the spectrum, not only because it introduces a new line, but also since it can substantially decrease the intensity of the magnetic dipole 2 p53 s P30→2 p53 s P31 line and affect the predicted ionization balance in different plasmas.

  10. Direct observation of electronic and nuclear ground state splitting in external magnetic field by inelastic neutron scattering on oxidized ferrocene and ferrocene containing polymers

    Directory of Open Access Journals (Sweden)

    Appel Markus

    2015-01-01

    Full Text Available The quantum mechanical splitting of states by interaction of a magnetic moment with an external magnetic field is well known, e.g., as Zeeman effect in optical transitions, and is also often seen in magnetic neutron scattering. We report excitations observed in inelastic neutron spectroscopy on the redox-responsive polymer poly(vinylferrocene. They are interpreted as splitting of the electronic ground state in the organometallic ferrocene units attached to the polymer chain where a magnetic moment is created by oxidation. In a second experiment using high resolution neutron backscattering spectroscopy we observe the hyperfine splitting, i.e., interaction of nuclear magnetic moments with external magnetic fields leading to sub-μeV excitations observable in incoherent neutron spin-flip scattering on hydrogen and vanadium nuclei.

  11. Non-split and split deformations of AdS_5

    CERN Document Server

    Hoare, Ben

    2016-01-01

    The eta-deformation of the AdS_5 x S^5 superstring depends on a non-split r matrix for the superalgebra psu(2,2|4). Much of the investigation into this model has considered one particular choice, however there are a number of inequivalent alternatives. This is also true for the bosonic sector of the theory with su(2,2), the isometry algebra of AdS_5, admitting one split and three non-split r matrices. In this article we explore these r matrices and the corresponding geometries. We investigate their contraction limits, comment on supergravity backgrounds and demonstrate their relation to gauged-WZW deformations. We then extend the three non-split cases to AdS_5 x S^5 and compute four separate bosonic two-particle tree-level S-matrices based on inequivalent BMN-type light-cone gauges. The resulting S-matrices, while different, are related by momentum-dependent one-particle changes of basis.

  12. Solar water splitting: efficiency discussion

    CERN Document Server

    Juodkazyte, Jurga; Sebeka, Benjaminas; Savickaja, Irena; Malinauskas, Tadas; Badokas, Kazimieras; Juodkazis, Kestutis; Juodkazis, Saulius

    2016-01-01

    The current state of the art in direct water splitting in photo-electrochemical cells (PECs) is presented together with: (i) a case study of water splitting using a simple solar cell with the most efficient water splitting electrodes and (ii) a detailed mechanism analysis. Detailed analysis of the energy balance and efficiency of solar hydrogen production are presented. The role of hydrogen peroxide formation as an intermediate in oxygen evolution reaction is newly revealed and explains why an oxygen evolution is not taking place at the thermodynamically expected 1.23 V potential. Solar hydrogen production with electrical-to-hydrogen conversion efficiency of 52% is demonstrated using a simple ~0.7%-efficient n-Si/Ni Schottky solar cell connected to a water electrolysis cell. This case study shows that separation of the processes of solar harvesting and electrolysis avoids photo-electrode corrosion and utilizes optimal electrodes for hydrogen and oxygen evolution reactions and achieves ~10% efficiency in light...

  13. Lattice splitting under intermittent flows

    CERN Document Server

    Schläpfer, Markus

    2010-01-01

    We study the splitting of regular square lattices subject to stochastic intermittent flows. By extensive Monte Carlo simulations we reveal how the time span until the occurence of a splitting depends on various flow patterns imposed on the lattices. Increasing the flow fluctuation frequencies shortens this time span which reaches a minimum before rising again due to inertia effects incorporated in the model. The size of the largest connected component after the splitting is rather independent of the flow fluctuations but sligthly decreases with the link capacities. Our results are relevant for assessing the robustness of real-life systems, such as electric power grids with a large share of renewable energy sources including wind turbines and photovoltaic systems.

  14. On Split Lie Triple Systems

    Indian Academy of Sciences (India)

    Antonio J Calderón Martín

    2009-04-01

    We begin the study of arbitrary split Lie triple systems by focussing on those with a coherent 0-root space. We show that any such triple systems with a symmetric root system is of the form $T=\\mathcal{U}+\\sum_j I_j$ with $\\mathcal{U}$ a subspace of the 0-root space $T_0$ and any $I_j$ a well described ideal of , satisfying $[I_j,T,I_k]=0$ if $j≠ k$. Under certain conditions, it is shown that is the direct sum of the family of its minimal ideals, each one being a simple split Lie triple system, and the simplicity of is characterized. The key tool in this job is the notion of connection of roots in the framework of split Lie triple systems.

  15. Split supersymmetry in brane models

    Indian Academy of Sciences (India)

    Ignatios Antoniadis

    2006-11-01

    Type-I string theory in the presence of internal magnetic fields provides a concrete realization of split supersymmetry. To lowest order, gauginos are massless while squarks and sleptons are superheavy. For weak magnetic fields, the correct Standard Model spectrum guarantees gauge coupling unification with sin2 W = 3/8 at the com-pactification scale of GUT ≃ 2 × 1016 GeV. I discuss mechanisms for generating gaugino and higgsino masses at the TeV scale, as well as generalizations to models with split extended supersymmetry in the gauge sector.

  16. Split NMSSM with electroweak baryogenesis

    Science.gov (United States)

    Demidov, S. V.; Gorbunov, D. S.; Kirpichnikov, D. V.

    2016-11-01

    In light of the Higgs boson discovery and other results of the LHC we re-consider generation of the baryon asymmetry in the split Supersymmetry model with an additional singlet superfield in the Higgs sector (non-minimal split SUSY). We find that successful baryogenesis during the first order electroweak phase transition is possible within a phenomenologically viable part of the model parameter space. We discuss several phenomenological consequences of this scenario, namely, predictions for the electric dipole moments of electron and neutron and collider signatures of light charginos and neutralinos.

  17. Splitting strings on integrable backgrounds

    Energy Technology Data Exchange (ETDEWEB)

    Vicedo, Benoit

    2011-05-15

    We use integrability to construct the general classical splitting string solution on R x S{sup 3}. Namely, given any incoming string solution satisfying a necessary self-intersection property at some given instant in time, we use the integrability of the worldsheet {sigma}-model to construct the pair of outgoing strings resulting from a split. The solution for each outgoing string is expressed recursively through a sequence of dressing transformations, the parameters of which are determined by the solutions to Birkhoff factorization problems in an appropriate real form of the loop group of SL{sub 2}(C). (orig.)

  18. Split Supersymmetry in String Theory

    CERN Document Server

    Antoniadis, Ignatios

    2006-01-01

    Type I string theory in the presence of internal magnetic fields provides a concrete realization of split supersymmetry. To lowest order, gauginos are massless while squarks and sleptons are superheavy. For weak magnetic fields, the correct Standard Model spectrum guarantees gauge coupling unification with \\sin^2{\\theta_W}=3/8 at the compactification scale of M_{\\rm GUT}\\simeq 2 \\times 10^{16} GeV. I discuss mechanisms for generating gaugino and higgsino masses at the TeV scale, as well as generalizations to models with split extended supersymmetry in the gauge sector.

  19. Quadrupole splitting and Eu partial lattice dynamics in europium orthophosphate EuPO 4

    Science.gov (United States)

    Klobes, B.; Arinicheva, Y.; Neumeier, S.; Simon, R. E.; Jafari, A.; Bosbach, D.; Hermann, R. P.

    2016-12-01

    Hyperfine interactions in europium orthophosphate EuPO4 were investigated using 151Eu Mössbauer spectroscopy from 6 to 300 K. The value of the quadrupole splitting and the asymmetry parameter were refined and further substantiated by nuclear forward scattering data obtained at room temperature. The temperature dependence of the relative absorption was modeled with an Eu specific Debye temperature of 221(1) K. Eu partial lattice dynamics were probed by means of nuclear inelastic scattering and the mean force constant, the Lamb-Mössbauer factor, the internal energy, the vibrational entropy, the average phonon group velocity were calculated using the extracted density of phonon states. In general, Eu specific vibrations are characterized by rather small phonon energies and contribute strongly to the total entropy of the system. Although there is no classical Debye like behavior at low vibrational energies, the average phonon group velocity can be reasonably approximated using a linear fit.

  20. Measurement of the Hyperfine Structure and Isotope Shifts of the 3s23p2 3P2 to 3s3p3 3Do3 Transition in Silicon

    CERN Document Server

    Lee, Siu Au

    2010-01-01

    The hyperfine structure and isotope shifts of the 3s23p2 3P2 to 3s3p3 3Do3 transition in silicon have been measured. The transition at 221.7 nm was studied by laser induced fluorescence in an atomic Si beam. For 29Si, the hyperfine A constant for the 3s23p2 3P2 level was determined to be -160.1+-1.3 MHz (1 sigma error), and the A constant for the 3s3p3 3Do3 level is -532.9+-0.6 MHz. This is the first time that these constants were measured. The isotope shifts (relative to the abundant isotope 28Si) of the transition were determined to be 1753.3+-1.1 MHz for 29Si and 3359.9+-0.6 MHz for 30Si. This is an improvement by about two orders of magnitude over a previous measurement. From these results we are able to predict the hyperfine structure and isotope shift of the radioactive 31Si atom, which is of interest in building a scalable quantum computer.

  1. Density functional study of electronic, magnetic and hyperfine properties of [M(CN){sub 5} NO]{sup 2-} (M=Fe, Ru) and reduction products

    Energy Technology Data Exchange (ETDEWEB)

    Gomez, J.A.; Guenzburger, Diana [Centro Brasileiro de Pesquisas Fisicas (CBPF), Rio de Janeiro, RJ (Brazil)

    1999-06-01

    The Discrete Variational method (DVM) in density functional theory was employed to investigate the electronic structure of the complexes [Fe(CN){sub 5} NO]{sup 2-} (Nitroprusside), [Fe(CN){sub 5} NO]{sup 3-}, [Fe(CN){sub 4} NO]{sup 2-}, [Ru(CN){sub 5} NO]{sup 2-} and [Ru(CN){sub 5} NO]{sup 3-}. Total energy calculations revealed that in pentacyano nitrosyl ferrate (I) and pentacyano nitrosyl ruthenate (I), which are paramagnetic ions containing one unpaired electron, the M-N-O angle is bent, having values of 152.5 deg and 144 deg, respectively. From self-consistent spin-polarized calculations, the distribution of unpaired electron in the paramagnetic complexes [Fe(CN){sub 5} NO]{sup 3,} [Fe(CN){sub 4} NO]{sup 2-} and [Ru(CN){sub 5} NO]{sup 3-}was obtained as well as spin-density maps. A long-standing controversy regarding the configuration of [Fe(CN){sub 5} NO]{sup 3-} was elucidated, and it was found that the unpaired electron in this complex is in an orbital primarily localized on {pi}{sup *} (NO). Moessbauer quadrupole splittings on Fe and Ru were derived from calculations of the electric-field gradients. Magnetic hyperfine coupling constants on No of the NO ligand were also obtained for the paramagnetic complexes. (author)

  2. Beam splitting on weak illumination.

    Science.gov (United States)

    Snyder, A W; Buryak, A V; Mitchell, D J

    1998-01-01

    We demonstrate, in both two and three dimensions, how a self-guided beam in a non-Kerr medium is split into two beams on weak illumination. We also provide an elegant physical explanation that predicts the universal character of the observed phenomenon. Possible applications of our findings to guiding light with light are also discussed.

  3. Torque-Splitting Gear Drive

    Science.gov (United States)

    Kish, J.

    1991-01-01

    Geared drive train transmits torque from input shaft in equal parts along two paths in parallel, then combines torques in single output shaft. Scheme reduces load on teeth of meshing gears while furnishing redundancy to protect against failures. Such splitting and recombination of torques common in design of turbine engines.

  4. Water splitting by cooperative catalysis

    NARCIS (Netherlands)

    D.G.H. Hetterscheid; J.I. van der Vlugt; B. de Bruin; J.N.H. Reek

    2009-01-01

    A mononuclear Ru complex is shown to efficiently split water into H2 and O2 in consecutive steps through a heat- and light-driven process (see picture). Thermally driven H2 formation involves the aid of a non-innocent ligand scaffold, while dioxygen is generated by initial photochemically induced re

  5. Raman transitions between hyperfine clock states in a magnetic trap

    CERN Document Server

    Naber, J B; Hubert, T; Spreeuw, R J C

    2016-01-01

    We present our experimental investigation of an optical Raman transition between the magnetic clock states of $^{87}$Rb in an atom chip magnetic trap. The transfer of atomic population is induced by a pair of diode lasers which couple the two clock states off-resonantly to an intermediate state manifold. This transition is subject to destructive interference of two excitation paths, which leads to a reduction of the effective two-photon Rabi-frequency. Furthermore, we find that the transition frequency is highly sensitive to the intensity ratio of the diode lasers. Our results are well described in terms of light shifts in the multi-level structure of $^{87}$Rb. The differential light shifts vanish at an optimal intensity ratio, which we observe as a narrowing of the transition linewidth. We also observe the temporal dynamics of the population transfer and find good agreement with a model based on the system's master equation and a Gaussian laser beam profile. Finally, we identify several sources of decoheren...

  6. Hyperfine structure in 229gTh3+ as a probe of the 229gTh→ 229mTh nuclear excitation energy.

    Science.gov (United States)

    Beloy, K

    2014-02-14

    We identify a potential means to extract the 229gTh→ 229mTh nuclear excitation energy from precision microwave spectroscopy of the 5F(5/2,7/2) hyperfine manifolds in the ion 229gTh3+. The hyperfine interaction mixes this ground fine structure doublet with states of the nuclear isomer, introducing small but observable shifts to the hyperfine sublevels. We demonstrate how accurate atomic structure calculations may be combined with the measurement of the hyperfine intervals to quantify the effects of this mixing. Further knowledge of the magnetic dipole decay rate of the isomer, as recently reported, allows an indirect determination of the nuclear excitation energy.

  7. Puzzling absence of hyperfine interaction in the D{sub 4h}RhCl{sub 6}{sup 4-} centre: role of the 4d-5s hybridization in Rh{sup 2+} centres

    Energy Technology Data Exchange (ETDEWEB)

    Barriuso, M.T. [Departamento de Fisica Moderna, Facultad de Ciencias, Universidad de Cantabria, Santander (Spain); Aramburu, J.A.; Moreno, M. [Departamento de Ciencias de la Tierra y Fisica de la Materia Condensada, Facultad de Ciencias, Universidad de Cantabria, Santander (Spain)

    2002-07-01

    The amazing absence of hyperfine interaction in EPR spectra of the tetragonally elongated RhCl{sub 6}{sup 4-} centre in NaCl is explored through the present work. In addition to the core polarization contribution it is shown that there is another isotropic contribution from the small 5s admixture in the a{sub 1g}*({approx}3z{sup 2} - r{sup 2}) level. These two contributions together with the anisotropic ones are shown to lead to a null hyperfine tensor for a 5s admixture of only {approx}1.5%. Density functional calculations reveal that such an admixture is strongly sensitive to the tetragonality of the RhCl{sub 6}{sup 4-} unit. Writing the axial (R{sub ax}) and equatorial (R{sub eq}) Rh{sup 2+}-Cl{sup -} distances as R{sub ax}=R{sub 0}+2a and R{sub eq}=R{sub 0} - a it is shown that (i) the 5s admixture is proportional to a{sup 2} (for a {<=}25 pm), a fact which can be accounted for through a simple model; (ii) relative variations of R{sub eq} and R{sub ax} of only -0.4 and 0.8% lead to a hyperfine constant of 7 MHz. The present results are shown to shed some light on EPR data of the orthorhombic RhCl{sub 6}{sup 4-} complex with two cis-equatorial Na{sup +} vacancies in the fourth shell. It is concluded that the hyperfine interaction measured for this centre can be explained in terms of the small strain induced by equatorial Na{sup +} vacancies upon the RhCl{sub 6}{sup 4-} unit. This idea can also explain the {approx}2% decrement of the isotropic axial superhyperfine constant when compared with that for the tetragonal RhCl{sub 6}{sup 4-} centre. (author)

  8. The hyperfine structure in the rotational spectra of D{sub 2}{sup 17}O and HD{sup 17}O: Confirmation of the absolute nuclear magnetic shielding scale for oxygen

    Energy Technology Data Exchange (ETDEWEB)

    Puzzarini, Cristina, E-mail: cristina.puzzarini@unibo.it; Cazzoli, Gabriele [Dipartimento di Chimica “Giacomo Ciamician,” Università degli Studi di Bologna, Via Selmi 2, I-40126 Bologna (Italy); Harding, Michael E. [Institut für Nanotechnologie, Karlsruher Institut für Technologie (KIT), Campus Nord, Postfach 3640, D-76021 Karlsruhe (Germany); Center for Theoretical Chemistry, Department of Chemistry and Biochemistry, University of Texas at Austin, Austin, Texas 78712 (United States); Vázquez, Juana [Center for Theoretical Chemistry, Department of Chemistry and Biochemistry, University of Texas at Austin, Austin, Texas 78712 (United States); Gauss, Jürgen, E-mail: gauss@uni-mainz.de [Institut für Physikalische Chemie, Universität Mainz, D-55099 Mainz (Germany)

    2015-03-28

    Guided by theoretical predictions, the hyperfine structures of the rotational spectra of mono- and bideuterated-water containing {sup 17}O have been experimentally investigated. To reach sub-Doppler resolution, required to resolve the hyperfine structure due to deuterium quadrupole coupling as well as to spin-rotation (SR) and dipolar spin-spin couplings, the Lamb-dip technique has been employed. The experimental investigation and in particular, the spectral analysis have been supported by high-level quantum-chemical computations employing coupled-cluster techniques and, for the first time, a complete experimental determination of the hyperfine parameters involved was possible. The experimentally determined {sup 17}O spin-rotation constants of D{sub 2}{sup 17}O and HD{sup 17}O were used to derive the paramagnetic part of the corresponding nuclear magnetic shielding constants. Together with the computed diamagnetic contributions as well as the vibrational and temperature corrections, the latter constants have been employed to confirm the oxygen nuclear magnetic shielding scale, recently established on the basis of spin-rotation data for H{sub 2}{sup 17}O [Puzzarini et al., J. Chem. Phys. 131, 234304 (2009)].

  9. Cool covered sky-splitting spectrum-splitting FK

    Energy Technology Data Exchange (ETDEWEB)

    Mohedano, Rubén; Chaves, Julio; Falicoff, Waqidi; Hernandez, Maikel; Sorgato, Simone [LPI, Altadena, CA, USA and Madrid (Spain); Miñano, Juan C.; Benitez, Pablo [LPI, Altadena, CA, USA and Madrid, Spain and Universidad Politécnica de Madrid (UPM), Madrid (Spain); Buljan, Marina [Universidad Politécnica de Madrid (UPM), Madrid (Spain)

    2014-09-26

    Placing a plane mirror between the primary lens and the receiver in a Fresnel Köhler (FK) concentrator gives birth to a quite different CPV system where all the high-tech components sit on a common plane, that of the primary lens panels. The idea enables not only a thinner device (a half of the original) but also a low cost 1-step manufacturing process for the optics, automatic alignment of primary and secondary lenses, and cell/wiring protection. The concept is also compatible with two different techniques to increase the module efficiency: spectrum splitting between a 3J and a BPC Silicon cell for better usage of Direct Normal Irradiance DNI, and sky splitting to harvest the energy of the diffuse radiation and higher energy production throughout the year. Simple calculations forecast the module would convert 45% of the DNI into electricity.

  10. Relativistic many-body calculation of energies, lifetimes, polarizabilities, blackbody radiative shift and hyperfine constants in Lu2+

    CERN Document Server

    Safronova, U I; Johnson, W R

    2016-01-01

    Energy levels of 30 low-lying states of Lu2+ and allowed electric-dipole matrix elements between these states are evaluated using a relativistic all-order method in which all single, double and partial triple excitations of Dirac-Fock wave functions are included to all orders of perturbation theory. Matrix elements are critically evaluated for their accuracy and recommended values of the matrix elements are given together with uncertainty estimates. Line strengths, transition rates and lifetimes of the metastable 5d(3/2) and 5d(5/2) states are calculated. Recommended values are given for static polarizabilities of the 6s, 5d and 6p states and tensor polarizabilities of the 5d and 6p(3/2) states. Uncertainties of the polarizability values are estimated in all cases. The blackbody radiation shift of the 6s(1/2)-5d(5/2) transition frequency of the Lu2+ ion is calculated with the aid of the recommended scalar polarizabilities of the 6s(1/2) and 5d(5/2) states. Finally, A and B hyperfine constants are determined f...

  11. Computation of the Isotropic Hyperfine Coupling Constant: Efficiency and Insights from a New Approach Based on Wave Function Theory.

    Science.gov (United States)

    Giner, Emmanuel; Tenti, Lorenzo; Angeli, Celestino; Ferré, Nicolas

    2017-02-14

    The present paper reports an original computational strategy for the computation of the isotropic hyperfine coupling constants (hcc). The algorithm proposed here is based on an approach recently introduced by some of the authors, namely, the first-order breathing orbital self-consistent field (FOBO-SCF). The approach is an almost parameter-free wave function method capable to accurately treat the spin delocalization together with the spin polarization effects while staying in a restricted formalism and avoiding spin contamination. The efficiency of the method is tested on a series of small radicals, among which four nitroxide radicals and the comparison with high-level ab initio methods show very encouraging results. On the basis of these results, the method is then applied to compute the hcc of a challenging system, namely, the DEPMPO-OOH radical in various conformations. The reference values obtained on such a large system allows us to validate a cheap computational method based on density functional theory (DFT). Another interesting feature of the model applied here is that it allows for the rationalization of the results according to a relatively simple scheme based on a two-step mechanism. More precisely, the results are analyzed in terms of two separated contributions: first the spin delocalization and then the spin polarization.

  12. Hyperfine interactions in nanocrystallized NANOPERM-type metallic glass containing Mo

    Science.gov (United States)

    Cesnek, M.; Kubániová, D.; Kohout, J.; Křišťan, P.; Štěpánková, H.; Závěta, K.; Lančok, A.; Štefánik, M.; Miglierini, M.

    2016-12-01

    NANOPERM-type alloy with chemical composition Fe76Mo8CuB15 was studied by combination of 57Fe Mössbauer spectroscopy and 57Fe(10B, 11B) nuclear magnetic resonance in order to determine distribution of hyperfine magnetic fields and evolution of relative concentration of Fe-containing crystalline phases within the surface layer and the volume of the nanocrystallized ribbons with annealing temperature. Differential scanning calorimetry revealed two crystallization stages at T x1 ˜ 510 ∘C and T x2 ˜ 640 ∘C, connected to precipitation of α-Fe and Fe(Mo,B) nanocrystals, respectively. The amorphous and partially crystalline state was obtained by annealing at several temperatures in the range 510-650 ∘C. The combination of conversion electron (CEMS) and transmission Mössbauer spectrometry (TMS) showed that annealing induces crystallization starting from both surfaces of the ribbons. For the as-quenched sample, scanning electron microscopy (SEM) and CEMS revealed significant differences in the "air" and "wheel" sides of the ribbons, crystallites were preferentially formed at the latter. While SEM micrographs of annealed samples showed various mean diameters of the crystals at opposite sides of the ribbons, the amounts of crystalline volume derived from the CEMS spectra approximately equaled. Mössbauer spectra of annealed samples contained narrow sextet ascribed to crystalline α-Fe phase, three sextets with distribution of hyperfine field assigned to the interface regions of the nanocrystals and the contribution of the amorphous phases. In-field TMS performed at 4.2 K with magnetic moments aligned by external magnetic field enabled to properly determine in particular the contribution of the amorphous phases in the samples. Resulting distributions of the hyperfine fields were compared with 57Fe(10B, 11B) nuclear magnetic resonance (NMR) spectra.

  13. Study of hyperfine parameters in Co-doped tin dioxide using PAC spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Ramos, Juliana M.; Carbonari, Artur W.; Martucci, Thiago; Costa, Messias S.; Saxena, Rajendra N. [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil); Vianden, R.; Kessler, P.; Geruschke, T.; Steffens, M., E-mail: vianden@hiskp.uni-bonn.d [Rheinische Friedrich-Wilhelms-Universitaet Bonn (HISKP- Bonn) (Germany). Helmholtz - Institut fuer Strahlen- und Kernphysik

    2011-07-01

    PAC technique has been used to measure the hyperfine interactions in nano-structured powder samples of semiconducting SnO{sub 2} doped with Co. The aim of this work is to compare the results of PAC measurements using two different techniques of introducing the radioactive {sup 111}In probe nuclei in the sample of SnO{sub 2} doped with Co. The perturbed gamma-gamma angular correlation (PAC) spectroscopy is used for the measurements of the magnetic hyperfine field (MHF) and the electric field gradient (EFG) at {sup 111}Cd sites in SnO{sub 2} doped with 1% and 2% Co. The measurement of EFG is used to study the defects introduced in the semiconductor material and also for the identification of different phases formed within the compound. The techniques utilized for introducing the radioactive {sup 111}In in the sample are the ion-implantation using radioactive ion beam of {sup 111}In and the chemical process in which {sup 111}InCl{sub 3} solution is added during the preparation of SnO{sub 2} doped with Co using sol gel method. The ion-implantation of {sup 111}In in SnO{sub 2} doped with Co was carried out using the University of Bonn ion-implanter with beam energy of 160 keV. The PAC measurements were carried out with four BaF{sub 2} detector gamma spectrometer in the temperature range of 10-295 K. The results show no significant difference in the values of hyperfine parameters. Both techniques show practically the same electric quadrupole interaction for the substitutional site. The results were compared with previous PAC and Moessbauer measurements of SnO{sub 2} powder samples using {sup 111}In-{sup 111}Cd probe. (author)

  14. Impact of silica environment on hyperfine interactions in 𝜖-Fe2O3 nanoparticles

    Science.gov (United States)

    Kubíčková, Lenka; Kohout, Jaroslav; Brázda, Petr; Veverka, Miroslav; Kmječ, Tomáš; Kubániová, Denisa; Bezdička, Petr; Klementová, Mariana; Šantavá, Eva; Závěta, Karel

    2016-12-01

    Magnetic nanoparticles have found broad applications in medicine, especially for cell targeting and transport, and as contrast agents in MRI. Our samples of 𝜖-Fe2O3 nanoparticles were prepared by annealing in silica matrix, which was leached off and the bare particles were then coated with amorphous silica layers of various thicknesses. The distribution of particle sizes was determined from the TEM pictures giving the average size ˜20 nm and the thickness of silica coating ˜5; 8; 12; 19 nm. The particles were further characterized by the XRPD and DC magnetic measurements. The nanoparticles consisted mainly of 𝜖-Fe2O3 with admixtures of ˜1 % of the α phase and less than 1 % of the γ phase. The hysteresis loops displayed coercivities of ˜2 T at room temperature. The parameters of hyperfine interactions were derived from transmission Mössbauer spectra. Observed differences of hyperfine fields for nanoparticles in the matrix and the bare ones are ascribed to strains produced during cooling of the composite. This interpretation is supported by slight changes of their lattice parameters and increase of the elementary cell volume deduced from XRD. The temperature dependence of the magnetization indicated a two-step magnetic transition of the 𝜖-Fe2O3 nanoparticles spread between ˜85 K and ˜150 K, which is slightly modified by remanent tensile stresses in the case of nanoparticles in the matrix. The subsequent coating of the bare particles by silica produced no further change in hyperfine parameters, which indicates that this procedure does not modify magnetic properties of nanoparticles.

  15. Neutral nitrogen acceptors in ZnO: The {sup 67}Zn hyperfine interactions

    Energy Technology Data Exchange (ETDEWEB)

    Golden, E. M.; Giles, N. C., E-mail: Nancy.Giles@afit.edu [Department of Engineering Physics, Air Force Institute of Technology, Wright-Patterson Air Force Base, Ohio 45433 (United States); Evans, S. M.; Halliburton, L. E. [Department of Physics, West Virginia University, Morgantown, West Virginia 26506 (United States)

    2014-03-14

    Electron paramagnetic resonance (EPR) is used to characterize the {sup 67}Zn hyperfine interactions associated with neutral nitrogen acceptors in zinc oxide. Data are obtained from an n-type bulk crystal grown by the seeded chemical vapor transport method. Singly ionized nitrogen acceptors (N{sup −}) initially present in the crystal are converted to their paramagnetic neutral charge state (N{sup 0}) during exposure at low temperature to 442 or 633 nm laser light. The EPR signals from these N{sup 0} acceptors are best observed near 5 K. Nitrogen substitutes for oxygen ions and has four nearest-neighbor cations. The zinc ion along the [0001] direction is referred to as an axial neighbor and the three equivalent zinc ions in the basal plane are referred to as nonaxial neighbors. For axial neighbors, the {sup 67}Zn hyperfine parameters are A{sub ‖} = 37.0 MHz and A{sub ⊥} = 8.4 MHz with the unique direction being [0001]. For nonaxial neighbors, the {sup 67}Zn parameters are A{sub 1} = 14.5 MHz, A{sub 2} = 18.3 MHz, and A{sub 3} = 20.5 MHz with A{sub 3} along a [101{sup ¯}0] direction (i.e., in the basal plane toward the nitrogen) and A{sub 2} along the [0001] direction. These {sup 67}Zn results and the related {sup 14}N hyperfine parameters provide information about the distribution of unpaired spin density at substitutional neutral nitrogen acceptors in ZnO.

  16. Dirac and Maxwell equations in Split Octonions

    CERN Document Server

    Beradze, Revaz

    2016-01-01

    The split octonionic form of Dirac and Maxwell equations are found. In contrast with the previous attempts these equations are derived from the octonionic analyticity condition and also we use different basis of the 8-dimensional space of split octonions.

  17. Entropy Analysis of Solar Two-Step Thermochemical Cycles for Water and Carbon Dioxide Splitting

    Directory of Open Access Journals (Sweden)

    Matthias Lange

    2016-01-01

    Full Text Available The present study provides a thermodynamic analysis of solar thermochemical cycles for splitting of H2O or CO2. Such cycles, powered by concentrated solar energy, have the potential to produce fuels in a sustainable way. We extend a previous study on the thermodynamics of water splitting by also taking into account CO2 splitting and the influence of the solar absorption efficiency. Based on this purely thermodynamic approach, efficiency trends are discussed. The comprehensive and vivid representation in T-S diagrams provides researchers in this field with the required theoretical background to improve process development. Furthermore, results about the required entropy change in the used redox materials can be used as a guideline for material developers. The results show that CO2 splitting is advantageous at higher temperature levels, while water splitting is more feasible at lower temperature levels, as it benefits from a great entropy change during the splitting step.

  18. Tuning the pseudo-Zeeman splitting in graphene cones by magnetic field

    Energy Technology Data Exchange (ETDEWEB)

    Kandemir, B.S.; Akay, D.

    2015-06-15

    The effect of a homogeneous magnetic field on the energy spectrum of gapped graphene cones with long range charged Coulomb impurity is investigated within the framework of the perturbation theory. It is found that, besides lifting the degeneracy of angular momentum channels due to topological defects, the size of the corresponding splitting is enhanced by the introduction of a homogeneous magnetic field. This indicates that the level splitting may be controlled by the strength of a magnetic field in topological cones. Therefore, our results show that the magnetic field may be used as a tool to tune the pseudo-Zeeman splitting in graphene cones. - Highlights: • The size of level splitting in angular momentum channels is enhanced by introduction of a homogenous magnetic field. • Pseudo-Zeeman splitting in graphene can be controlled by hydrogenic impurities. • Pseudo-Zeeman splitting may be controlled by the strength of magnetic field in topological cones.

  19. The 57Fe hyperfine interactions in the iron-bearing phases in some LL ordinary chondrites

    Science.gov (United States)

    Oshtrakh, M. I.; Maksimova, A. A.; Grokhovsky, V. I.; Petrova, E. V.; Semionkin, V. A.

    2016-12-01

    The study of several LL ordinary chondrites such as NWA 6286 LL6, NWA 7857 LL6 and Chelyabinsk LL5 fragments with different lithology was carried out using scanning electron microscopy with energy dispersion spectroscopy, X-ray diffraction and 57Fe Mössbauer spectroscopy with a high velocity resolution at 295 K. Small variations in the 57Fe hyperfine parameters were revealed for the M1 and M2 sites in olivine, orthopyroxene and clinopyroxene as well as for α-Fe(Ni, Co), α 2-Fe(Ni, Co) and γ-Fe(Ni, Co) phases, and for troilite in different samples of studied LL ordinary chondrites.

  20. Orientation of hyperfine magnetic fields of {alpha}-iron films produced by laser deposition

    Energy Technology Data Exchange (ETDEWEB)

    Yasuike, Mamoru, E-mail: yyasu@rs.kagu.tus.ac.jp; Usui, Ryo; Yamada, Yasuhiro [Tokyo University of Science (Japan); Kobayashi, Yoshio [RIKEN (Japan)

    2012-03-15

    Iron films were produced by pulsed laser deposition (PLD) of iron in Ar gas and Moessbauer spectra of these films were obtained at room temperature. The orientation of the hyperfine magnetic field was found to vary depending on the pressure of the Ar gas. Iron films produced at low Ar pressures exhibited magnetic fields parallel to the substrate surface. The magnetic field became increasingly perpendicular to the substrate with increasing Ar pressure. Collisions with Ar gas molecules reduced the translational energies of laser-evaporated iron atoms and thus the orientation of crystals formed on the substrate varied depending on the Ar pressure.

  1. Calculation of hyperfine coupling constant by symmetry adapted cluster expansion configuration interaction theory. II. Anisotropic constants

    Science.gov (United States)

    Momose, Takamasa; Yamaguchi, Makoto; Shida, Tadamasa

    1990-11-01

    Following the previous work on the isotropic hyperfine coupling constants (HFCCs) of polyatomic radicals the symmetry adapted cluster expansion-configuration interaction (SAC-CI) theory is applied to calculate anisotropic HFCCs also. The results are compared with available experimental data from diatomic to polyatomic radicals such as the vinoxy. For radicals consisting of only the first row atoms Dunning's double zeta (DZ) basis set is shown to be adequate, but for those containing the second row atoms inclusion of polarization functions is required. Compared with the isotropic HFCC the calculation of the anisotropic HFCC is less formidable. However, ignorance of electron correlation causes serious disagreements with experimental data.

  2. Quantum spacetime fluctuations: Lamb Shift and hyperfine structure of the hydrogen atom

    CERN Document Server

    Rivas, Juan Israel; Goeklue, Ertan

    2011-01-01

    We consider the consequences of the presence of metric fluctuations upon the properties of a hydrogen atom. Particularly, we introduce these metric fluctuations in the corresponding effective Schroedinger equation and deduce the modifications that they entail upon the hyperfine structure related to a hydrogen atom. We will find the change that these effects imply for the ground state energy of the system and obtain a bound for its size comparing our theoretical predictions against the experimental uncertainty reported in the literature. In addition, we analyze the corresponding Lamb shift effect emerging from these fluctuations of spacetime. Once again, we will set a bound to these oscillations resorting to the current experimental outcomes

  3. Incomplete Erasure of Which-Way Information Encoded in Atomic Hyperfine States

    Institute of Scientific and Technical Information of China (English)

    WEN Ling-Hua; LIU Min; KONG Ling-Bo; ZHAN Ming-Sheng

    2005-01-01

    @@ We propose an experimental scheme to investigate incomplete erasure of which-way information encoded in atomic hyperfine states.Due to the incomplete erasure of the which-way information, it is shown that the interference patterns of the atomic wave packets initially confined in a spin-dependent optical lattice are destroyed to a certain extent, which provides a new straight way to test further the validity of the theoretical model developed in our recent work.The remarkable merit of the proposal is that it is simple and can be implemented easily.

  4. Variations of {sup 57}Fe hyperfine parameters in medicaments containing ferrous fumarate and ferrous sulfate

    Energy Technology Data Exchange (ETDEWEB)

    Oshtrakh, M. I., E-mail: oshtrakh@mail.utnet.ru; Novikov, E. G. [Ural Federal University (The former Ural State Technical University-UPI), Faculty of Physical Techniques and Devices for Quality Control (Russian Federation); Dubiel, S. M. [AGH University of Science and Technology, Faculty of Physics and Computer Science (Poland); Semionkin, V. A. [Ural Federal University (The former Ural State Technical University-UPI), Faculty of Physical Techniques and Devices for Quality Control (Russian Federation)

    2010-04-15

    Several commercially available medicaments containing ferrous fumarate (FeC{sub 4}H{sub 2}O{sub 4}) and ferrous sulfate (FeSO{sub 4}), as a source of ferrous iron, were studied using a high velocity resolution Moessbauer spectroscopy. A comparison of the {sup 57}Fe hyperfine parameters revealed small variations for the main components in both medicaments indicating some differences in the ferrous fumarates and ferrous sulfates. It was also found that all spectra contained additional minor components probably related to ferrous and ferric impurities or to partially modified main components.

  5. Split Left GC-Lpp Semigroups

    Institute of Scientific and Technical Information of China (English)

    Zhen Zhen LI; Xiao Jiang GUO; Zhi Qing FU

    2012-01-01

    A left GC-lpp semigroup S is called split if the natural homomorphism γb of S onto S/γ induced by γ is split.It is proved that a left GC-lpp semigroup is split if and only if it has a left adequate transversal.In particular,a construction theorem for split left GC-lpp semigroups is established.

  6. Image Segmentation Using Two Step Splitting Function

    Directory of Open Access Journals (Sweden)

    Gopal Kumar Jha

    2013-12-01

    Full Text Available Image processing and computer vision is widely using Level Set Method (LSM. In conventional level set formulation, irregularities are developed during evolution of level set function, which cause numerical errors and eventually destroy the stability of the evolution. Therefore a numerical remedy called re-initialization is typically applied periodically to replace the degraded level set function. However re –initialization raises serious problem that is when and how it should be performed and also affects numerical accuracy in an undesirable way. To overcome this drawback of re-initialization process, a new variation level set formulation called Distance regularization level set evolution (DRLSE is introduced in which the regularity of the level set function is internally maintained during the level set evolution. DRLSE allows more general and effective initialization of the level set function. But DRLSE uses relatively large number of steps to ensure efficient numerical accuracy. Here in this thesis we are implementing faster and equally efficient computation technique called two step splitting method (TSSM. TSSM is physio-chemical reaction diffusion equation in which firstly LSE equation get iterated and then regularize the level set function from the first step to ensure the stability and hence re-initialization is completely eliminated from LSE which also satisfy DRLSE.

  7. Effects of Restricted Rotations and Dynamic Averaging on the Calculated Isotropic Hyperfine Coupling Constants of the bis-Dimethyl and bis-Di(trifluoromethyl) Nitroxide Radicals

    Science.gov (United States)

    Mattar, Saba M.; Sanford, Jacob

    2009-09-01

    The rotational effects of the CH3 and CF3 groups on the electronic structure and nuclear hyperfine coupling constants (HFCCs) in dimethylnitroxide (DMNO·) and ditrifluoro-methynitroxide (TFMNO·) are investigated using the UB1LYP hybrid density functional method. The CH3 and CF3 HFCCs of both radicals are found to obey the McConnell relation during rotation. The two CH3 groups of the DMNO· do not gear with each other, but the rotation of the first CH3 group induces only a small rocking effect (˜7°) in the second group. However, in TFMNO·, the fluorine atoms from different CF3 groups are close enough so that the steric repulsion between them causes them to act as two interlocked gears, where one drives the other. Therefore, both CF3 groups undergo full rotation. To the best of our knowledge, this is only the second example of "gearing" to be studied. Stabilization due to hyperconjugation is also a major factor that affects the magnitudes of the HFCCs of the CF3 groups during rotational averaging. Stable configurations at specific CF3 group orientations have a large overlap with the NO π-electron cloud because the lobes of the hybridized pσ(F2), pσ(F3), pσ(F5), and pσ(F6) orbitals along the F-C bonds have cylindrical symmetry and are of the correct phases for hyperconjugation to occur. The calculated TFMNO· C1-N and C2-N bond orders range from 0.91 to 0.95 as the CF3 groups are rotated. Therefore, the C-N bonds are essentially single bonds. This, in conjunction with the low rotational energy barrier of approximately 50 cm-1, explains why the EPR intensities of the 19F hyperfine splittings, in the range of 163-297 K, are characteristic of six equivalent rapidly rotating fluorine atoms. The TFMNO· out-of-plane NO vibrations induce additional s character at the 14N nucleus. This increases the magnitude of the 14N HFCC and decreases the 19F HFCCs. As the temperature increases and because of mixing of the first excited out-of-plane vibrational state, the NO

  8. 7 CFR 51.2002 - Split shell.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 2 2010-01-01 2010-01-01 false Split shell. 51.2002 Section 51.2002 Agriculture... Standards for Grades of Filberts in the Shell 1 Definitions § 51.2002 Split shell. Split shell means a shell... of the shell, measured in the direction of the crack....

  9. Split NMSSM with electroweak baryogenesis

    CERN Document Server

    Demidov, S V; Kirpichnikov, D V

    2016-01-01

    In light of the Higgs boson discovery we reconsider generation of the baryon asymmetry in the non-minimal split Supersymmetry model with an additional singlet superfield in the Higgs sector. We find that successful baryogenesis during the first order electroweak phase transition is possible within phenomenologically viable part of the model parameter space. We discuss several phenomenological consequences of this scenario, namely, predictions for the electric dipole moments of electron and neutron and collider signatures of light charginos and neutralinos.

  10. The Split Variational Inequality Problem

    CERN Document Server

    Censor, Yair; Reich, Simeon

    2010-01-01

    We propose a new variational problem which we call the Split Variational Inequality Problem (SVIP). It entails finding a solution of one Variational Inequality Problem (VIP), the image of which under a given bounded linear transformation is a solution of another VIP. We construct iterative algorithms that solve such problems, under reasonable conditions, in Hilbert space and then discuss special cases, some of which are new even in Euclidean space.

  11. Torsional Split Hopkinson Bar Optimization

    Science.gov (United States)

    2012-04-10

    pillow blocks used to mount the incident and transmitter bars are cast iron based- mounted Babbitt -lined bearing split, for 1 in. shaft diameter...Total 1 McMaster-CARR 5911k16 1" Dia, 6" long anodized aluminum shaft $15.38 8 $123.04 2 McMaster-CARR 6359k37 Cast iron base-mounted babbitt

  12. Geometrical Applications of Split Octonions

    Directory of Open Access Journals (Sweden)

    Merab Gogberashvili

    2015-01-01

    Full Text Available It is shown that physical signals and space-time intervals modeled on split-octonion geometry naturally exhibit properties from conventional (3 + 1-theory (e.g., number of dimensions, existence of maximal velocities, Heisenberg uncertainty, and particle generations. This paper demonstrates these properties using an explicit representation of the automorphisms on split-octonions, the noncompact form of the exceptional Lie group G2. This group generates specific rotations of (3 + 4-vector parts of split octonions with three extra time-like coordinates and in infinitesimal limit imitates standard Poincare transformations. In this picture translations are represented by noncompact Lorentz-type rotations towards the extra time-like coordinates. It is shown how the G2 algebra’s chirality yields an intrinsic left-right asymmetry of a certain 3-vector (spin, as well as a parity violating effect on light emitted by a moving quantum system. Elementary particles are connected with the special elements of the algebra which nullify octonionic intervals. Then the zero-norm conditions lead to free particle Lagrangians, which allow virtual trajectories also and exhibit the appearance of spatial horizons governing by mass parameters.

  13. Testing split supersymmetry with inflation

    Science.gov (United States)

    Craig, Nathaniel; Green, Daniel

    2014-07-01

    Split supersymmetry (SUSY) — in which SUSY is relevant to our universe but largely inaccessible at current accelerators — has become increasingly plausible given the absence of new physics at the LHC, the success of gauge coupling unification, and the observed Higgs mass. Indirect probes of split SUSY such as electric dipole moments (EDMs) and flavor violation offer hope for further evidence but are ultimately limited in their reach. Inflation offers an alternate window into SUSY through the direct production of superpartners during inflation. These particles are capable of leaving imprints in future cosmological probes of primordial non-gaussianity. Given the recent observations of BICEP2, the scale of inflation is likely high enough to probe the full range of split SUSY scenarios and therefore offers a unique advantage over low energy probes. The key observable for future experiments is equilateral non-gaussianity, which will be probed by both cosmic microwave background (CMB) and large scale structure (LSS) surveys. In the event of a detection, we forecast our ability to find evidence for superpartners through the scaling behavior in the squeezed limit of the bispectrum.

  14. Hyperfine-induced quadrupole moments of alkali-metal atom ground states and their implications for atomic clocks

    CERN Document Server

    Derevianko, Andrei

    2016-01-01

    Spherically-symmetric ground states of alkali-metal atoms do not posses electric quadrupole moments. However, the hyperfine interaction between nuclear moments and atomic electrons distorts the spherical symmetry of electronic clouds and leads to non-vanishing atomic quadrupole moments. We evaluate these hyperfine-induced quadrupole moments using techniques of relativistic many-body theory and compile results for Li, Na, K, Rb, and Cs atoms. For heavy atoms we find that the hyperfine-induced quadrupole moments are strongly (two orders of magnitude) enhanced by correlation effects. We further apply the results of the calculation to microwave atomic clocks where the coupling of atomic quadrupole moments to gradients of electric fields leads to clock frequency uncertainties. We show that for $^{133}$Cs atomic clocks, the spatial gradients of electric fields must be smaller than $30 \\, \\mathrm{V}/\\mathrm{cm}^2$ to guarantee fractional inaccuracies below $10^{-16}$.

  15. Analysis of the Torsional Splitting in the νb{8} Band of Propane Near 870.4 wn Caused by Fermi Resonance with the 2νb{14}+2νb{27} Level

    Science.gov (United States)

    Groner, Peter; Perrin, Agnes; Kwabia Tchana, F.; Manceron, Laurent

    2016-06-01

    Torsional splitting has been observed in the νb{8} and νb{21} IR bands of propane near 870.4 and 921.4 wn, respectively, recorded at the AILES Beamline at the SOLEIL synchrotron. Over 4000 individual transitions of the νb{8} band were assigned and analyzed with an expanded version of the effective rotational Hamiltonian for molecules with two symmetric internal rotors (ERHAM). A least-squares fit approximated a large portion of the assigned transitions with a model of an isolated νb{8} state with acceptable precision. However, this model was unable to reproduce many systematic deviations and local resonances. A torsional analysis of existing experimental data and ab initio predictions allows the conclusion that Fermi resonance between νb{8} and the torsional combination state 2νb{14}+2νb{27} most likely caused the failure of the isolated state model. Additional modifications to ERHAM that include Fermi resonance with another state support the conclusion that most of the observed torsional splitting in νb{8} is caused by the 2νb{14}+2νb{27} state. The continuing detailed analysis is expected to yield more definitive results by the time of this meeting. A. Perrin et al., J. Mol. Spectrosc. 315 (2015), 55-62; A. Perrin et al., ISMS15, presentation TG04. P. Groner, J. Chem. Phys. 107 (1997) 4483-4498; P. Groner, J. Mol. Spectrosc. 278 (2012) 52-67.

  16. Hyperfine interactions and some thermomagnetic properties of amorphous FeZr(CrNbBCu alloys

    Directory of Open Access Journals (Sweden)

    Łukiewska Agnieszka

    2017-06-01

    Full Text Available In this research, we studied the magnetic phase transition by Mössbauer spectroscopy and using vibrating sample magnetometer for amorphous Fe86-xZr7CrxNb2Cu1B4 (x = 0 or 6 alloys in the as-quenched state and after accumulative annealing in the temperature range 600-750 K. The Mössbauer investigations were carried out at room and nitrogen temperatures. The Mössbauer spectra of the investigated alloys at room temperature are characteristic of amorphous paramagnets and have a form of asymmetric doublets. However, at nitrogen temperature, the alloys behave like ferromagnetic amorphous materials. The two components are distinguished in the spectrum recorded at both room and nitrogen temperatures. The low field component in the distribution of hyperfine field induction shifts towards higher field with the annealing temperature. It is assumed that during annealing at higher temperature, due to diffusion processes, the grains of α-Fe are created in the area corresponding to this component. Both investigated alloys show the invar effect and the decrease of hyperfine field induction after annealing at 600 K for 10 min is observed. It is accompanied by the lowering of Curie temperature.

  17. Hyperfine interaction mechanism of magnetic field effects in sequential fluorophore and exciplex fluorescence

    Science.gov (United States)

    Dodin, Dmitry V.; Ivanov, Anatoly I.; Burshtein, Anatoly I.

    2013-03-01

    The magnetic field effect on the fluorescence of the photoexcited electron acceptor, 1A*, and the exciplex, 1[D+δA-δ] formed at contact of 1A* with an electron donor 1D, is theoretically explored in the framework of Integral Encounter Theory. It is assumed that the excited fluorophore is equilibrated with the exciplex that reversibly dissociates into the radical-ion pair. The magnetic field sensitive stage is the spin conversion in the resulting geminate radical-ion pair, 1, 3[D+…A-] that proceeds due to hyperfine interaction. We confirm our earlier conclusion (obtained with a rate description of spin conversion) that in the model with a single nucleus spin 1/2 the magnitude of the Magnetic Field Effect (MFE) also vanishes in the opposite limits of low and high dielectric permittivity of the solvent. Moreover, it is shown that MFE being positive at small hyperfine interaction A, first increases with A but approaching the maximum starts to decrease and even changes the sign.

  18. Frequency swept microwaves for hyperfine decoupling and time domain dynamic nuclear polarization.

    Science.gov (United States)

    Hoff, Daniel E M; Albert, Brice J; Saliba, Edward P; Scott, Faith J; Choi, Eric J; Mardini, Michael; Barnes, Alexander B

    2015-11-01

    Hyperfine decoupling and pulsed dynamic nuclear polarization (DNP) are promising techniques to improve high field DNP NMR. We explore experimental and theoretical considerations to implement them with magic angle spinning (MAS). Microwave field simulations using the high frequency structural simulator (HFSS) software suite are performed to characterize the inhomogeneous phase independent microwave field throughout a 198GHz MAS DNP probe. Our calculations show that a microwave power input of 17W is required to generate an average EPR nutation frequency of 0.84MHz. We also present a detailed calculation of microwave heating from the HFSS parameters and find that 7.1% of the incident microwave power contributes to dielectric sample heating. Voltage tunable gyrotron oscillators are proposed as a class of frequency agile microwave sources to generate microwave frequency sweeps required for the frequency modulated cross effect, electron spin inversions, and hyperfine decoupling. Electron spin inversions of stable organic radicals are simulated with SPINEVOLUTION using the inhomogeneous microwave fields calculated by HFSS. We calculate an electron spin inversion efficiency of 56% at a spinning frequency of 5kHz. Finally, we demonstrate gyrotron acceleration potentials required to generate swept microwave frequency profiles for the frequency modulated cross effect and electron spin inversions. Copyright © 2015 Elsevier Inc. All rights reserved.

  19. Orbital hyperfine interaction and qubit dephasing in carbon nanotube quantum dots

    Science.gov (United States)

    Palyi, Andras; Csiszar, Gabor

    2015-03-01

    Hyperfine interaction (HF) is of key importance for the functionality of solid-state quantum information processing, as it affects qubit coherence and enables nuclear-spin quantum memories. In this work, we complete the theory of the basic hyperfine interaction mechanisms (Fermi contact, dipolar, orbital) in carbon nanotube quantum dots by providing a theoretical description of the orbital HF. We find that orbital HF induces an interaction between the nuclear spins of the nanotube lattice and the valley degree of freedom of the electrons confined in the quantum dot. We show that the resulting nuclear-spin-electron-valley interaction (i) is approximately of Ising type, (ii) is essentially local, in the sense that an effective atomic interaction strength can be defined, and (iii) has a strength that is comparable to the combined strength of Fermi contact and dipolar interactions. We argue that orbital HF provides a new decoherence mechanism for single-electron valley qubits and spin-valley qubits in a range of multi-valley materials. We explicitly evaluate the corresponding inhomogeneous dephasing time T2* for a nanotube-based valley qubit. We acknowledge funding from the EU Marie Curie CIG-293834, OTKA Grant PD 100373, and EU ERC Starting Grant CooPairEnt 258789. AP is supported by the Janos Bolyai Scholarship of the Hungarian Academy of Sciences.

  20. Electronic structure and hyperfine parameters of substitutional Al and P impurities in silica

    DEFF Research Database (Denmark)

    Lægsgaard, Jesper; Stokbro, Kurt

    2002-01-01

    The electronic structure of substitutional Al and P impurities in silica is investigated using supercell calculations within the framework of density functional theory (DFT). Evaluation of hyperfine matrices for the magnetic nuclei facilitates comparison to experimental data. It is found that the......, there is an "asymmetry" between electrons and holes in the electronic states of the silica network: The hole present at the Al impurity goes into a nonbonding O orbital while the extra electron present at the P impurity goes into a P-O antibonding state.......The electronic structure of substitutional Al and P impurities in silica is investigated using supercell calculations within the framework of density functional theory (DFT). Evaluation of hyperfine matrices for the magnetic nuclei facilitates comparison to experimental data. It is found...... that the impaired spin state of substitutional P is well described by the theory, while the unpaired spin state found for substitutional Al is severely at variance with the experimental data. Cluster calculations using both the DFT and the Hartree-Fock approximation indicate that the problem is not caused...

  1. Alternating tip splitting in directional solidification.

    Science.gov (United States)

    Utter, B; Ragnarsson, R; Bodenschatz, E

    2001-05-14

    We report experimental results on the tip splitting dynamics of seaweed growth in directional solidification of succinonitrile alloys. Despite the random appearance of the growth, a tip splitting morphology was observed in which the tip alternately splits to the left and to the right. The tip splitting frequency f was found to be related to the growth velocity V as a power law f~V1.5. This finding is consistent with the predictions of a tip splitting model that is also presented. Small anisotropies are shown to lead to different kinds of seaweed morphologies.

  2. Magnetic hyperfine structure of the ground-state doublet in highly charged ions 89+,87+229Th and the Bohr-Weisskopf effect

    Science.gov (United States)

    Tkalya, E. V.; Nikolaev, A. V.

    2016-07-01

    Background: The search for new opportunities to investigate the low-energy level in the 229Th nucleus, which is nowadays intensively studied experimentally, has motivated us to theoretical studies of the magnetic hyperfine (MHF) structure of the 5 /2+ (0.0 eV) ground state and the low-lying 3 /2+ (7.8 eV) isomeric state in highly charged 89+229Th and 87+229Th ions. Purpose: The aim is to calculate, with the maximal precision presently achievable, the energy of levels of the hyperfine structure of the 229Th ground-state doublet in highly charged ions and the probability of radiative transitions between these levels. Methods: The distribution of the nuclear magnetization (the Bohr-Weisskopf effect) is accounted for in the framework of the collective nuclear model with Nilsson model wave functions for the unpaired neutron. Numerical calculations using precise atomic density functional theory methods, with full account of the electron self-consistent field, have been performed for the electron structure inside and outside the nuclear region. Results: The deviations of the MHF structure for the ground and isomeric states from their values in a model of a pointlike nuclear magnetic dipole are calculated. The influence of the mixing of the states with the same quantum number F on the energy of sublevels is studied. Taking into account the mixing of states, the probabilities of the transitions between the components of the MHF structure are calculated. Conclusions: Our findings are relevant for experiments with highly ionized 229Th ions in a storage ring at an accelerator facility.

  3. Hyperfine and magnetic properties of Fe-Cu clusters and Fe precipitates embedded in a Cu matrix

    Energy Technology Data Exchange (ETDEWEB)

    Klautau, A B [Faculdade de Fisica, Universidade Federal do Para, 66075-110, Belem, PA (Brazil); Socolovsky, L M [Laboratorio de Solidos Amorfos, INTECIN, Facultad de Ingenieria, Universidad de Buenos Aires, C1063ACV, Buenos Aires (Argentina); Nogueira, R N [Faculdade Taboao da Serra, 06768-000, Taboao da Serra, SP (Brazil); Petrilli, H M, E-mail: aklautau@ufpa.b [Instituto de Fisica, Universidade de Sao Paulo, CP 66318, 05315-970 Sao Paulo, SP (Brazil)

    2009-12-16

    Using the first-principles real-space linear muffin-tin orbital method within the atomic sphere approximation (RS-LMTO-ASA) we study hyperfine and local magnetic properties of substituted pure Fe and Fe-Cu clusters in an fcc Cu matrix. Spin and orbital contributions to magnetic moments, hyperfine fields and the Moessbauer isomer shifts at the Fe sites in Fe precipitates and Fe-Cu alloy clusters of sizes up to 60 Fe atoms embedded in the Cu matrix are calculated and the influence of the local environment on these properties is discussed.

  4. Characterization of hyperfine interaction between an NV electron spin and a first-shell 13C nuclear spin in diamond

    Science.gov (United States)

    Rao, K. Rama Koteswara; Suter, Dieter

    2016-08-01

    The nitrogen-vacancy (NV) center in diamond has attractive properties for a number of quantum technologies that rely on the spin angular momentum of the electron and the nuclei adjacent to the center. The nucleus with the strongest interaction is the 13C nuclear spin of the first shell. Using this degree of freedom effectively hinges on precise data on the hyperfine interaction between the electronic and the nuclear spin. Here, we present detailed experimental data on this interaction, together with an analysis that yields all parameters of the hyperfine tensor, as well as its orientation with respect to the atomic structure of the center.

  5. Split-and-merge Procedure for Image Segmentation using Bimodality Detection Approach

    Directory of Open Access Journals (Sweden)

    Debasis Chaudhuri

    2010-04-01

    Full Text Available Image segmentation, the division of a multi-dimensional image into groups of associated pixels, is an essential step for many advanced imaging applications. Image segmentation can be performed by recursively splitting the whole image or by merging together a large number of minute regions until a specified condition is satisfied. The split-and-merge procedure of image segmentation takes an  intermediate level in an image description as the starting cutest, and thereby achieves a compromise between merging small primitive regions and recursively splitting the whole images to reach the desired final cutest. The proposed segmentation approach is a split-andmerge technique. The conventional split-and-merge algorithm is lacking in adaptability to the image semantics because of its stiff quadtree-based structure. In this paper, an automatic thresholding technique based on bimodality detection approach with non-homogeneity criterion is employed in the splitting phase of the split-and-merge segmentation scheme to directly reflect the image semantics to the image segmentation results. Since the proposed splitting technique depends upon homogeneity factor, some of the split regions may or may not split properly. There should be rechecking through merging technique between the two adjacent regions to overcome the drawback of the splitting technique. A sequential-arrange-based or a minimal spanning-tree based approach, that depends on data dimensionality of the weighted centroids of all split regions for finding the pair wise adjacent regions, is introduced. Finally, to overcome the problems caused by the splitting technique, a novel merging technique based on the density ratio of the adjacent pair regions is proposed. The algorithm has been tested on several synthetic as well as real life data and the results show the efficiency of the segmentation technique.Defence Science Journal, 2010, 60(3, pp.290-301, DOI:http://dx.doi.org/10.14429/dsj.60.356

  6. Design of a Cocoa Pod Splitting Machine

    Directory of Open Access Journals (Sweden)

    Adetunde, I.A

    2010-10-01

    Full Text Available This study outlines the design of a very efficient, highly productive, cost- effective, ergonomic and environmentally friendly cocoa splitting machine that will be used by cocoa Farmers world - wide to increase and boost productivity and enhance the quality of coca products to the highest possible level devoid of any hazards, dangers or perils. This machine can be manufactured from locally available scraps and assembled and maintained at a relatively low cost. The knives which do the splitting are actuated by simple hydraulic mechanisms devoid any major stresses, forces or moments acting on them. These mechanisms are powered by simple low - powered lobe positive displacement or hydrostatic hydraulic pumps of power rating of 87.5 kW (65.625 Hp. The machine can be assembled and/or disassembled easily and quickly, and, therefore can be owned patronized by a group of cocoa farmers who can easily bear the low cost of maintenance of the already relative cheap machine.

  7. Trap split with Laguerre-Gaussian beams

    Science.gov (United States)

    Hamideh Kazemi, Seyedeh; Ghanbari, Saeed; Mahmoudi, Mohammad

    2017-08-01

    We present a convenient and effective way to generate a novel phenomenon of trapping, named ‘trap split’, in a conventional four-level double-Λ atomic system, driven by four femtosecond Laguerre-Gaussian laser pulses. We find that trap split can always be achieved when atoms are trapped by such laser pulses, as compared to Gaussian ones. This feature is enabled by the interaction of the atomic system and the Laguerre-Gaussian laser pulses with zero intensity in the center. A further advantage of using Laguerre-Gaussian laser pulses is the insensitivity to fluctuation in the intensity of the lasers in such a way that the separation between the traps remains constant. Moreover, it is demonstrated that the suggested scheme with Laguerre-Gaussian laser pulses can form optical traps with spatial sizes that are not limited by the wavelength of the laser, and can, in principle, become smaller than the wavelength of light. This work would greatly facilitate the trapping and manipulating of particles and the generation of trap split. It may also suggest the possibility of extension into new research fields, such as micro-machining and biophysics.

  8. Improved V II log($gf$) Values, Hyperfine Structure Constants, and Abundance Determinations in the Photospheres of the Sun and Metal-poor Star HD 84937

    CERN Document Server

    Wood, M P; Hartog, E A Den; Sneden, C; Cowan, J J

    2014-01-01

    New experimental absolute atomic transition probabilities are reported for 203 lines of V II. Branching fractions are measured from spectra recorded using a Fourier transform spectrometer and an echelle spectrometer. The branching fractions are normalized with radiative lifetime measurements to determine the new transition probabilities. Generally good agreement is found between this work and previously reported V II transition probabilities. Use of two spectrometers, independent radiometric calibration methods, and independent data analysis routines enables a reduction in systematic uncertainties, in particular those due to optical depth errors. In addition, new hyperfine structure constants are measured for selected levels by least squares fitting line profiles in the FTS spectra. The new V II data are applied to high resolution visible and UV spectra of the Sun and metal-poor star HD 84937 to determine new, more accurate V abundances. Lines covering a range of wavelength and excitation potential are used t...

  9. Circadian regulation of cortisol release in behaviorally split golden hamsters.

    Science.gov (United States)

    Lilley, Travis R; Wotus, Cheryl; Taylor, Daniel; Lee, Jennifer M; de la Iglesia, Horacio O

    2012-02-01

    The master circadian clock located within the hypothalamic suprachiasmatic nucleus (SCN) is necessary for the circadian rhythm of glucocorticoid (GC) release. The pathways by which the SCN sustains rhythmic GC release remain unclear. We studied the circadian regulation of cortisol release in the behaviorally split golden hamster, in which the single bout of circadian locomotor activity splits into two bouts approximately 12 h apart after exposing the animals to constant light conditions. We show that unsplit control hamsters present a single peak of cortisol release that is concomitant with a single peak of ACTH release. In contrast, split hamsters show two peaks of cortisol release that are approximately 12 h appart and are appropriately phased to each locomotor activity bout but surprisingly do not rely on rhythmic release of ACTH. Our results are consistent with a model in which the circadian pacemaker within the SCN regulates the circadian release of GC via input to the hypothalamo-pituitary-adrenal axis and via a second regulatory pathway, which likely involves sympathetic innervation of the adrenal and can operate even in the absence of ACTH circadian rhythmic release. Furthermore, we show that although the overall 24-h cortisol output in split hamsters is lower than in unsplit controls, split hamsters release constant low levels of ACTH. This result suggests that the timing, rather than the absolute amount, of cortisol release is more critical for the induction of negative feedback effects that regulate the hypothalamo-pituitary-adrenal axis.

  10. Constructing General Orthogonal Fractional Factorial Split-Plot Designs

    NARCIS (Netherlands)

    Sartono, B.; Goos, P.; Schoen, E.

    2015-01-01

    While the orthogonal design of split-plot fractional factorial experiments has received much attention already, there are still major voids in the literature. First, designs with one or more factors acting at more than two levels have not yet been considered. Second, published work on nonregular fra

  11. Long segment composite split cord malformation with double bony spur

    Directory of Open Access Journals (Sweden)

    Sharma Anand

    2015-09-01

    Full Text Available A composite type of SCM is very rare and only a few cases have been reported until today. The frequency of composite- type SCM is lower than 1% in the literature. In this report, we presented an unusual case of long segment composite type split cord malformation with double level bony spur with multiple associated bony anomalies.

  12. CBM split title in Alberta

    Energy Technology Data Exchange (ETDEWEB)

    Campbell, L.M. [EnCana Corp., Calgary, AB (Canada); Laurin, W.

    2006-07-01

    Coalbed methane (CBM) coal underlies most of central and southern Alberta. This article discussed disputes surrounding CBM ownership and split-titles. Historically, ownership of lands in Alberta implied possession and rights of all under- and overground substances. Surface estates are now typically separated from the subsurface estate, and subsurface estates are further divided either on the basis of substances or stratigraphically to create a split-title. Mineral severances are used to separate respective mineral rights among owners. While there is a relative certainty that under provincial Crown tenure CBM is included in natural gas tenure, there is currently no Canadian jurisprudence in respect of CBM entitlement on split-title private lands. Where compressed natural gas (CNG) and coal are separately held, and CBM ownership is not specifically addressed in the mineral severance, there is no Canadian law respecting CBM ownership. Resolution of ownership issues has proceeded on a case by case basis. Coal owners argue that there is a distinct interrelationship between CBM and its host coal strata. Gas owners argue that the chemical composition of CBM is identical to CNG, and that the recovery method is similar to that of CNG. Courts have historically applied the vernacular test to resolve mineral substance ownership disputes, which considers the meanings of the word coal and coalbed methane as defined by industry. The most recent and relevant application of the vernacular test were the Borys/Anderson, which effectively implemented a gas-oil interface ownership determination, which if applied to a coal grant or reservation, may lead to the conclusion that the coal strata includes CBM. It was concluded that there are 26,000 individual mineral owners in Alberta that may become involved in CBM litigation. and could become parties to litigation. refs., tabs., figs.

  13. Partitions of generalized split graphs

    OpenAIRE

    Shklarsky, Oren

    2012-01-01

    We discuss matrix partition problems for graphs that admit a partition into k independent sets and ` cliques. We show that when k + ` 6 2, any matrix M has finitely many (k; `) minimal obstructions and hence all of these problems are polynomial time solvable. We provide upper bounds for the size of any (k; `) minimal obstruction when k = ` = 1 (split graphs), when k = 2; ` = 0 (bipartite graphs), and when k = 0; ` = 2 (co-bipartite graphs). When k = ` = 1, we construct an exponential size spl...

  14. Generalized Forward-Backward Splitting

    OpenAIRE

    2011-01-01

    International audience; This paper introduces a generalized forward-backward splitting algorithm for finding a zero of a sum of maximal monotone operators $B + \\sum_{i=1}^{n} A_i$, where $B$ is cocoercive. It involves the computation of $B$ in an explicit (forward) step and of the parallel computation of the resolvents of the $A_i$'s in a subsequent implicit (backward) step. We prove its convergence in infinite dimension, and robustness to summable errors on the computed operators in the expl...

  15. Split-plot Experiments with Unusual Numbers of Subplot Runs

    DEFF Research Database (Denmark)

    Kulahci, Murat

    2007-01-01

    In many experimental situations, it may not be feasible or even possible to run experiments in a completely randomized fashion as usually recommended. Under these circumstances, split-plot experiments in which certain factors are changed less frequently than the others are often used. Most...... of the literature on split-plot designs is based on 2-level factorials. For those designs, the number of subplots is a power of 2. There may however be some situations where for cost purposes or physical constraints, we may need to have unusual number of subplots such as 3, 5, 6, etc. In this article, we explore...... this issue and provide some examples based on the Plackett and Burman designs. Also algorithmically constructed D-optimal split-plot designs are compared to those based on Plackett and Burman designs....

  16. Rectangular split-ring resonators with single-split and two-splits under different excitations at microwave frequencies

    Directory of Open Access Journals (Sweden)

    S. Zahertar

    2015-11-01

    Full Text Available In this work, transmission characteristics of rectangular split-ring resonators with single-split and two-splits are analyzed at microwave frequencies. The resonators are coupled with monopole antennas for excitation. The scattering parameters of the devices are investigated under different polarizations of E and H fields. The magnetic resonances induced by E and H fields are identified and the differences in the behavior of the resonators due to orientations of the fields are explained based on simulation and experimental results. The addition of the second split of the device is investigated considering different configurations of the excitation vectors. It is demonstrated that the single-split and the two-splits resonators exhibit identical transmission characteristics for a certain excitation configuration as verified with simulations and experiments. The presented resonators can effectively function as frequency selective media for varying excitation conditions.

  17. Hyperfine interactions in nanocrystallized NANOPERM-type metallic glass containing Mo

    Energy Technology Data Exchange (ETDEWEB)

    Cesnek, M., E-mail: martin.cesnek@fjfi.cvut.cz [Czech Technical University in Prague, Department of Nuclear Reactors, Faculty of Nuclear Science and Physical Engineering (Czech Republic); Kubániová, D.; Kohout, J.; Křišťan, P.; Štěpánková, H.; Závěta, K. [Charles University, Department of Low Temperature Physics, Faculty of Mathematics and Physics (Czech Republic); Lančok, A. [Institute of Inorganic Chemistry AS CR (Czech Republic); Štefánik, M.; Miglierini, M. [Czech Technical University in Prague, Department of Nuclear Reactors, Faculty of Nuclear Science and Physical Engineering (Czech Republic)

    2016-12-15

    NANOPERM-type alloy with chemical composition Fe{sub 76}Mo{sub 8}CuB{sub 15} was studied by combination of {sup 57}Fe Mössbauer spectroscopy and {sup 57}Fe({sup 10}B, {sup 11}B) nuclear magnetic resonance in order to determine distribution of hyperfine magnetic fields and evolution of relative concentration of Fe-containing crystalline phases within the surface layer and the volume of the nanocrystallized ribbons with annealing temperature. Differential scanning calorimetry revealed two crystallization stages at T{sub x1} ∼ 510 {sup ∘}C and T{sub x2} ∼ 640 {sup ∘}C, connected to precipitation of α-Fe and Fe(Mo,B) nanocrystals, respectively. The amorphous and partially crystalline state was obtained by annealing at several temperatures in the range 510-650 {sup ∘}C. The combination of conversion electron (CEMS) and transmission Mössbauer spectrometry (TMS) showed that annealing induces crystallization starting from both surfaces of the ribbons. For the as-quenched sample, scanning electron microscopy (SEM) and CEMS revealed significant differences in the “air” and “wheel” sides of the ribbons, crystallites were preferentially formed at the latter. While SEM micrographs of annealed samples showed various mean diameters of the crystals at opposite sides of the ribbons, the amounts of crystalline volume derived from the CEMS spectra approximately equaled. Mössbauer spectra of annealed samples contained narrow sextet ascribed to crystalline α-Fe phase, three sextets with distribution of hyperfine field assigned to the interface regions of the nanocrystals and the contribution of the amorphous phases. In-field TMS performed at 4.2 K with magnetic moments aligned by external magnetic field enabled to properly determine in particular the contribution of the amorphous phases in the samples. Resulting distributions of the hyperfine fields were compared with {sup 57}Fe({sup 10}B, {sup 11}B) nuclear magnetic resonance (NMR) spectra.

  18. Generalized Forward-Backward Splitting

    CERN Document Server

    Raguet, Hugo; Peyré, Gabriel

    2011-01-01

    This paper introduces the generalized forward-backward splitting algorithm for minimizing convex functions of the form $F + \\sum_{i=1}^n G_i$, where $F$ has a Lipschitz-continuous gradient and the $G_i$'s are simple in the sense that their Moreau proximity operators are easy to compute. While the forward-backward algorithm cannot deal with more than $n = 1$ non-smooth function, our method generalizes it to the case of arbitrary $n$. Our method makes an explicit use of the regularity of $F$ in the forward step, and the proximity operators of the $G_i$'s are applied in parallel in the backward step. This allows the generalized forward backward to efficiently address an important class of convex problems. We prove its convergence in infinite dimension, and its robustness to errors on the computation of the proximity operators and of the gradient of $F$. Examples on inverse problems in imaging demonstrate the advantage of the proposed methods in comparison to other splitting algorithms.

  19. THE SPLITTING OF COMET HALLEY

    Institute of Scientific and Technical Information of China (English)

    Chen Daohan; Liu Linzhong; Alan Gilmore

    2000-01-01

    In combination with the authors previous obsewation about the splitting of Comet Halley in March 1986, the events involving the sharp, straight feature in the antisolar direction observed in the head of Comet Halley in 1910 (such as those occurring on May 14, 25 and 31, and June 2) are rediscussed The analysis leads to the following scenario: When Comet Halley explodes and splits, a fragment jettisoned or thrown off from the nucleus will, after moving in the direction of its tail, develop into a mini-comet. Although not well developed or permanent, it has its own plasma tail and, sometimes, a dust tail. If Bobrovnikoffs definition of a secondary nucleus is assumed, then the fragment should be considered as a real secondary nucleus. It seems that the current idea of a tailward jet suggested by Sekanina and Larson is a wrong explanation for the plasma tail of a mini-comet and hence the rotation period of 52-53h for Comet Halley is doubtful

  20. The splitting of Comet Halley

    Institute of Scientific and Technical Information of China (English)

    陈道汉; 刘麟仲; Alan Gilmore

    1995-01-01

    In combination with the authors’ previous observation about the splitting of Comet Halley in March 1986, the events involving the sharp, straight feature in the antisolar direction observed in the bead of Comet Halley in 1910 (such as those occurring on May 14, 25 and 31, and June 2) are rediscussed. The analysis leads to the following scenario: When Comet Halley explodes and splits, a fragment jettisoned or thrown off from the nucleus will, after moving in the direction of its tail, develop into a mini-comet. Although not well developed or permanent, it has its own plasma tail and, sometimes, a dust tail. If Bobrovnikoff’s definition of a secondary nucleus is assumed, then the fragment should be considered as a real secondary nucleus. It seems that the current idea of a tailward jet suggested by Sekanina and Larson is a wrong explanation for the plasma tail of a mini-comet and hence the rotation period of 52- 53 h for Comet Halley is doubtful.

  1. Structural, electronic, and hyperfine properties of pure and Ta-doped m-ZrO2

    DEFF Research Database (Denmark)

    Taylor, M.A.; Alonso, R.E.; Errico, L.A.

    2012-01-01

    A combination of experiments and ab initio quantum-mechanical calculations has been applied to examine electronic, structural, and hyperfine interactions in pure and Ta-doped zirconium dioxide in its monoclinic phase (m-ZrO2). From the theoretical point of view, the full-potential linear augmented...

  2. Hyperfine excitation of linear molecules by para- and ortho-H2: application to the HCl-H2 system.

    Science.gov (United States)

    Lanza, Mathieu; Lique, François

    2014-10-28

    The determination of hyperfine structure resolved excitation cross sections and rate coefficients due to H2 collisions is required to interpret astronomical spectra. In this paper, we present several theoretical approaches to compute these data. An almost exact recoupling approach and approximate sudden methods are presented. We apply these different approaches to the HCl-H2 collisional system in order to evaluate their respective accuracy. HCl-H2 hyperfine structure resolved cross sections and rate coefficients are then computed using recoupling and approximate sudden methods. As expected, the approximate sudden approaches are more accurate when the collision energy increases and the results suggest that these approaches work better for para-H2 than for ortho-H2 colliding partner. For the first time, we present HCl-H2 hyperfine structure resolved rate coefficients, computed here for temperatures ranging from 5 to 300 K. The usual Δj1 = ΔF1 propensity rules are observed for the hyperfine transitions. The new rate coefficients will significantly help the interpretation of interstellar HCl emission lines observed with current and future telescopes. We expect that these new data will allow a better determination of the HCl abundance in the interstellar medium, that is crucial to understand the interstellar chlorine chemistry.

  3. Hyperfine interactions in soybean and lupin oxy-leghemoglobins studied using Mössbauer spectroscopy with a high velocity resolution

    Energy Technology Data Exchange (ETDEWEB)

    Kumar, A. [University of Delhi South Campus, Department of Biochemistry (India); Alenkina, I. V. [Ural Federal University, Department of Physical Techniques and Devices for Quality Control, Institute of Physics and Technology (Russian Federation); Zakharova, A. P. [Ural Federal University, Department of Experimental Physics, Institute of Physics and Technology (Russian Federation); Oshtrakh, M. I., E-mail: oshtrakh@gmail.com; Semionkin, V. A. [Ural Federal University, Department of Physical Techniques and Devices for Quality Control, Institute of Physics and Technology (Russian Federation)

    2015-04-15

    A comparative study of monomeric soybean and lupin leghemoglobins in the oxy-form was carried out using Mössbauer spectroscopy with a high velocity resolution at 90 K. The {sup 57}Fe hyperfine parameters of measured spectra were evaluated and compared with possible structural differences in the heme Fe(II)–O {sub 2} bond.

  4. Algebraic techniques for diagonalization of a split quaternion matrix in split quaternionic mechanics

    Energy Technology Data Exchange (ETDEWEB)

    Jiang, Tongsong, E-mail: jiangtongsong@sina.com [Department of Mathematics, Linyi University, Linyi, Shandong 276005 (China); Department of Mathematics, Heze University, Heze, Shandong 274015 (China); Jiang, Ziwu; Zhang, Zhaozhong [Department of Mathematics, Linyi University, Linyi, Shandong 276005 (China)

    2015-08-15

    In the study of the relation between complexified classical and non-Hermitian quantum mechanics, physicists found that there are links to quaternionic and split quaternionic mechanics, and this leads to the possibility of employing algebraic techniques of split quaternions to tackle some problems in complexified classical and quantum mechanics. This paper, by means of real representation of a split quaternion matrix, studies the problem of diagonalization of a split quaternion matrix and gives algebraic techniques for diagonalization of split quaternion matrices in split quaternionic mechanics.

  5. Telugu Bigram Splitting using Consonant-based and Phrase-based Splitting

    Directory of Open Access Journals (Sweden)

    T. Kameswara Rao

    2014-06-01

    Full Text Available Splitting is a conventional process in most of Indian languages according to their grammar rules. It is called ‘pada vicchEdanam’ (a Sanskrit term for word splitting and is widely used by most of the Indian languages. Splitting plays a key role in Machine Translation (MT particularly when the source language (SL is an Indian language. Though this splitting may not succeed completely in extracting the root words of which the compound is formed, but it shows considerable impact in Natural Language Processing (NLP as an important phase. Though there are many types of splitting, this paper considers only consonant based and phrase based splitting.

  6. Modeling habitat split: landscape and life history traits determine amphibian extinction thresholds.

    Directory of Open Access Journals (Sweden)

    Carlos Roberto Fonseca

    Full Text Available Habitat split is a major force behind the worldwide decline of amphibian populations, causing community change in richness and species composition. In fragmented landscapes, natural remnants, the terrestrial habitat of the adults, are frequently separated from streams, the aquatic habitat of the larvae. An important question is how this landscape configuration affects population levels and if it can drive species to extinction locally. Here, we put forward the first theoretical model on habitat split which is particularly concerned on how split distance - the distance between the two required habitats - affects population size and persistence in isolated fragments. Our diffusive model shows that habitat split alone is able to generate extinction thresholds. Fragments occurring between the aquatic habitat and a given critical split distance are expected to hold viable populations, while fragments located farther away are expected to be unoccupied. Species with higher reproductive success and higher diffusion rate of post-metamorphic youngs are expected to have farther critical split distances. Furthermore, the model indicates that negative effects of habitat split are poorly compensated by positive effects of fragment size. The habitat split model improves our understanding about spatially structured populations and has relevant implications for landscape design for conservation. It puts on a firm theoretical basis the relation between habitat split and the decline of amphibian populations.

  7. A Comparison of Splitting Techniques for 3D Complex Padé Fourier Finite Difference Migration

    Directory of Open Access Journals (Sweden)

    Jessé C. Costa

    2011-01-01

    Full Text Available Three-dimensional wave-equation migration techniques are still quite expensive because of the huge matrices that need to be inverted. Several techniques have been proposed to reduce this cost by splitting the full 3D problem into a sequence of 2D problems. We compare the performance of splitting techniques for stable 3D Fourier finite-difference (FFD migration techniques in terms of image quality and computational cost. The FFD methods are complex Padé FFD and FFD plus interpolation, and the compared splitting techniques are two- and four-way splitting as well as alternating four-way splitting, that is, splitting into the coordinate directions at one depth and the diagonal directions at the next depth level. From numerical examples in homogeneous and inhomogeneous media, we conclude that, though theoretically less accurate, alternate four-way splitting yields results of comparable quality as full four-way splitting at the cost of two-way splitting.

  8. Radiative corrections to the muonium hyperfine structure; 1, the $\\alpha^{2}$ (Z$\\alpha$) correction

    CERN Document Server

    Kinoshita, T

    1995-01-01

    This is the first of a series of papers on a systematic application of the NRQED bound state theory of Caswell and Lepage to higher-order radiative corrections to the hyperfine structure of the muonium ground state. This paper describes the calculation of the \\alpha^2 (Z\\alpha) radiative correction. Our result for the complete \\alpha^2 (Z\\alpha) correction is 0.424(4) kHz, which reduces the theoretical uncertainty significantly. The remaining uncertainty is dominated by that of the numerical evaluation of the nonlogarithmic part of the \\alpha (Z\\alpha )^2 term and logarithmic terms of order \\alpha^4. These terms will be treated in the subsequent papers.

  9. Radiative Corrections to the Muonium Hyperfine Structure; 2, The $\\alpha (Z\\alpha)^2$ Correction

    CERN Document Server

    Nio, M

    1997-01-01

    This is the second of a series of papers on the radiative corrections of order $\\alpha^2 (Z\\alpha)$, $\\alpha (Z\\alpha )^2$, and various logarithmic terms of order $\\alpha^4$, to the hyperfine structure of the muonium ground state. This paper deals with the $\\alpha (Z\\alpha)^2$ correction. Based on the NRQED bound state theory, we isolated the term of order $\\alpha(Z\\alpha)^2$ exactly. Our result $+16.904~2~(11) \\alpha(Z\\alpha)^2 E_F / \\pi$ for the non-logarithmic part is consistent with the $\\alpha (Z\\alpha)^2$ part of Sapirstein's calculation and the recent result of Pachucki, and reduces the numerical uncertainty in the $\\alpha (Z\\alpha)^2$ term by two orders of magnitude.

  10. Centrifugal correction to hyperfine structure constants in the ground state of lead monofluoride, PbF

    CERN Document Server

    Petrov, A N; Titov, A V; Mawhorter, R J

    2013-01-01

    The sensitivity of the PbF molecule to the electron electric dipole moment has motivated detailed microwave spectroscopy. Previous theoretical approaches cannot fully explain the spectra. In turn, the explanation from "first principles" is very important both for molecular theory and for confirmation of the correctness of the interpretation of experimental data obtained with high precision. All of these issues are decisively addressed here. We have determined centrifugal correction parameters for hyperfine structure constants, both on lead and fluorine nuclei, of the $X^2\\Pi_{1/2}$ state of lead monofluoride. These parameters were obtained by fitting experimentally observed pure rotational transitions and from {\\it ab initio} calculations. We show that taking this correction into account is required to reproduce the experimental transition energies obtained in [Phys. Rev. A 84, 022508 (2011)].

  11. A triple resonance hyperfine sublevel correlation experiment for assignment of electron-nuclear double resonance lines

    Science.gov (United States)

    Potapov, Alexey; Epel, Boris; Goldfarb, Daniella

    2008-02-01

    A new, triple resonance, pulse electron paramagnetic resonance (EPR) sequence is described. It provides spin links between forbidden electron spin transitions (ΔMS=±1, ΔMI≠0) and allowed nuclear spin transitions (ΔMI=±1), thus, facilitating the assignment of nuclear frequencies to their respective electron spin manifolds and paramagnetic centers. It also yields the relative signs of the hyperfine couplings of the different nuclei. The technique is based on the combination of electron-nuclear double resonance (ENDOR) and electron-electron double resonance (ELDOR)-detected NMR experiments in a way similar to the TRIPLE experiment. The feasibility and the information content of the method are demonstrated first on a single crystal of Cu-doped L-histidine and then on a frozen solution of a Cu-histidine complex.

  12. Hyperfine frequencies of 87Rb and 133Cs atoms in Xe gas

    CERN Document Server

    McGuyer, B H; Happer, W; 10.1103/PhysRevA.84.030501

    2013-01-01

    The microwave resonant frequencies of ground-state 87Rb and 133Cs atoms in Xe buffer gas are shown to have a relatively large nonlinear dependence on the Xe pressure, presumably because of RbXe or CsXe van der Waals molecules. The nonlinear shifts for Xe are opposite in sign to the previously measured shifts for Ar and Kr, even though all three gases have negative linear shifts. The Xe data show striking discrepancies with the previous theory for nonlinear shifts. Most of this discrepancy is eliminated by accounting for the spin-rotation interaction in addition to the hyperfine-shift interaction in the molecules. To the limit of our experimental accuracy, the shifts of 87Rb and 133Cs in He, Ne, and N2 were linear with pressure.

  13. Maraging-350 steel: Following the aging through diffractometric, magnetic and hyperfine analysis

    Science.gov (United States)

    Nunes, G. C. S.; Sarvezuk, P. W. C.; Alves, T. J. B.; Biondo, V.; Ivashita, F. F.; Paesano, A.

    2017-01-01

    Plates of solution annealed Maraging-350 steel were submitted to aging under an inert atmosphere, varying the time and temperature. The aged samples were characterized by X-ray diffraction and Mössbauer spectroscopy. The results revealed that the aging treatments induced the reversion of austenite, in amounts that vary with the time and the temperature of the heat treatment. The lattice parameters of the martensite and austenite phases, as well as their hyperfine parameters, were obtained at all aging conditions. No intermetallic compounds were identified in any of the aged samples, but a poorly crystallized phase fraction, the consequence of an incomplete martensite ⇒ austenite reversion transformation, was observed for some samples. The tetragonal distortion from cubic symmetry presented by the martensite in the solution annealed steel was not eliminated after aging.

  14. Precise measurements of hyperfine components in the spectrum of molecular iodine

    Energy Technology Data Exchange (ETDEWEB)

    Sansonetti, C.J. [National Inst. of Standards and Technology, Gaithersburg, MD (United States)

    1996-05-01

    Absolute wave numbers with a typical uncertainty of 1 MHz (95% confidence) were measured for 102 hyperfine-structure components of {sup 127}I{sub 2}. The data cover the range 560-656 nm, with no gaps over 50 cm{sup -1}. The spectra were observed using Doppler-free frequency modulation spectroscopy with tunable cw laser. The laser was locked to selected iodine components and its wave number measured with a high precision Fabry-Perot wavemeter. Accuracy is confirmed by good agreement of 9 of the lines with previous results from other laboratories. These measurements provide a well-distributed set of precise reference lines for this spectral region.

  15. Sternheimer free determination of the 47Ti nuclear quadrupole moment from hyperfine structure measurements

    Science.gov (United States)

    Aydin, R.; Stachowska, E.; Johann, U.; Dembczyński, J.; Unkel, P.; Ertmer, W.

    1990-12-01

    The hyperfine structure (hfs) of 12 metastable states of47Ti has been measured by laser induced fluorescence. 11 of these states have been measured additionally very precisely by a laser-rf double resonance method. Taking into account results of earlier hfs measurements, the hfs of altogether 17 fine structure states has been analyzed by the simultaneous parametrization of the one- and two-body interactions in the atomic hfs for the model space (3 d+4 s) N+2 ( N=2). This gives 16 parameters for the magnetic dipole interaction and 12 parameters for the electric quadrupole interaction. From the model space parameters, obtained from the hfs fit, the nuclear quadrupole moment Q(47Ti)=0.303(24b), has been evaluated at the first time; it is free of Sternheimer corrections up to second order.

  16. A path integral molecular dynamics study of the hyperfine coupling constants of the muoniated and hydrogenated acetone radicals

    Science.gov (United States)

    Oba, Yuki; Kawatsu, Tsutomu; Tachikawa, Masanori

    2016-08-01

    The on-the-fly ab initio density functional path integral molecular dynamics (PIMD) simulations, which can account for both the nuclear quantum effect and thermal effect, were carried out to evaluate the structures and "reduced" isotropic hyperfine coupling constants (HFCCs) for muoniated and hydrogenated acetone radicals (2-muoxy-2-propyl and 2-hydoxy-2-propyl) in vacuo. The reduced HFCC value from a simple geometry optimization calculation without both the nuclear quantum effect and thermal effect is -8.18 MHz, and that by standard ab initio molecular dynamics simulation with only the thermal effect and without the nuclear quantum effect is 0.33 MHz at 300 K, where these two methods cannot distinguish the difference between muoniated and hydrogenated acetone radicals. In contrast, the reduced HFCC value of the muoniated acetone radical by our PIMD simulation is 32.1 MHz, which is about 8 times larger than that for the hydrogenated radical of 3.97 MHz with the same level of calculation. We have found that the HFCC values are highly correlated with the local molecular structures; especially, the Mu—O bond length in the muoniated acetone radical is elongated due to the large nuclear quantum effect of the muon, which makes the expectation value of the HFCC larger. Although our PIMD result calculated in vacuo is about 4 times larger than the measured experimental value in aqueous solvent, the ratio of these HFCC values between muoniated and hydrogenated acetone radicals in vacuo is in reasonable agreement with the ratio of the experimental values in aqueous solvent (8.56 MHz and 0.9 MHz); the explicit presence of solvent molecules has a major effect on decreasing the reduced muon HFCC of in vacuo calculations for the quantitative reproduction.

  17. Hyperfine interaction and tuning of magnetic anisotropy of Cu doped CoFe{sub 2}O{sub 4} ferrite nanoparticles

    Energy Technology Data Exchange (ETDEWEB)

    Batoo, Khalid Mujasam, E-mail: khalid.mujasam@gmail.com [King Abdullah Institute for Nanotechnology, King Saud University, P.O. Box-2455, Riyadh 11451 (Saudi Arabia); Salah, Dina [Department of Physics, Ain Shams University, Khalifa El-Maamon, Street, 11566 Cairo (Egypt); Kumar, Gagan; Kumar, Arun; Singh, Mahavir [Department of Physics, Himachal Pradesh University, Summer Hill, Shimla 171005 (India); Abd El-sadek, M. [Nanomaterials Lab, Physics Department, Faculty of Science, South Valley University, Qena 83523 (Egypt); Mir, Feroz Ahmad [University Science Instrumentation Centre, University of Kashmir, Srinagar 190006 (India); Imran, Ahamad [King Abdullah Institute for Nanotechnology, King Saud University, P.O. Box-2455, Riyadh 11451 (Saudi Arabia); Jameel, Daler Adil [School of Physics and Astronomy, Nottingham Nanotechnology and Nanoscience Center, University of Nottingham, NG7 2RD (United Kingdom)

    2016-08-01

    Ferrimagnetic oxides may contain single or multi domain particles which get converted into superparamagnetic state near a critical size. To explore the existence of these particles, we have made Mössbauer and magnetic studies of Cu{sup 2+} substitution effect in CoFe{sub 2−x}O{sub 4} Ferrites (0.0, 0.1, 0.2, 0.3, 0.4, and 0.5). All the samples have a cubic spinel structure with lattice parameters increasing linearly with increase in Cu content. The hysteresis loops yield a saturation magnetization, coercive field, and remanent magnetization that vary significantly with Cu content. The magnetic hysteresis curves shows a reduction in saturation magnetization and an increase in coercitivity with Cu{sup 2+} ion substitution. The anisotropy constant, K{sub 1,} is found strongly dependent on the composition of Cu{sup 2+} ions. The variation of saturation magnetization with increasing Cu{sup 2+} ion content has been explained in the light of Neel's molecular field theory. Mössbauer spectra at room temperature shows two ferrimagnetically relaxed Zeeman sextets. The dependence of Mössbauer parameters such as isomer shift, quadrupole splitting, line width and hyperfine magnetic field on Cu{sup 2+} ion concentration have been discussed. - Highlights: • Synthesis of the nanoparticles of Cu doped CoFe{sub 2}O{sub 4} ferrite nanoparticles. • The samples were characterized for the structural, morphological and magnetic studies using XRD, TEM, VSM and Mossbauer spectroscopy. • It has been found that the all the magnetic and Mossbauer parameters are diluted with the addition of Cu content in the CoFe{sub 2}O{sub 4} matrix. • The Mossbauer and magnetic properties were studied in the light of size of nanoparticles and also with respect to the doping composition.

  18. Equation of state and hyperfine parameters of high-spin bridgmanite in the Earth’s lower mantle by synchrotron X-ray diffraction and Mössbauer spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Mao, Zhu; Wang, Fan; Lin, Jung-Fu; Fu, Suyu; Yang, Jing; Wu, Xiang; Okuchi, Takuo; Tomioka, Naotaka; Prakapenka, Vitali B.; Xiao, Yuming; Chow, Paul

    2017-02-01

    In this study, we performed synchrotron X-ray diffraction (XRD) and Mössbauer spectroscopy (SMS) measurements on two single-crystal bridgmanite samples [ Embedded Image and Embedded Image ] to investigate the combined effect of Fe and Al on the hyperfine parameters, lattice parameters, and equation of state (EoS) of bridgmanite up to 130 GPa. Our SMS results show that Fe2+ and Fe3+ in Bm6 and Al-Bm11 are predominantly located in the large pseudo-dodecahedral sites (A-site) at lower-mantle pressures. The observed drastic increase in the hyperfine quadrupole splitting (QS) between 13 and 32 GPa can be associated with an enhanced local distortion of the A-site Fe2+ in Bm6. In contrast to Bm6, the enhanced lattice distortion and the presence of extremely high QS values of Fe2+ are not observed in Al-Bm11 at high pressures. Our results here support the notion that the occurrence of the extremely high QS component of approximately 4 mm/s in bridgmanite is due to the lattice distortion in the high-spin (HS) A-site Fe2+, instead of the occurrence of the intermediate-spin state. Both A-site Fe2+ and Fe3+ in Bm6 and Al-Bm11 remain in the HS state at lower-mantle pressures. Together with XRD results, we present the first experimental evidence that the enhanced lattice distortion of A-site Fe2+ does not cause any detectable variation in the EoS parameters, but is associated with anomalous variations in the bond length, tilting angle, and shear strain in the octahedra of Bm6. Analysis of the obtained EoS parameters of bridgmanite at lower-mantle pressures indicates that the substitution of Fe in bridgmanite will cause an enhanced density and a reduced bulk sound velocity (VΦ), whereas the Al and Fe substitution has a reduced effect on density and a negligible effect on VΦ. These experimental results provide new insight into the correlation between lattice, hyperfine, and EoS parameters of bridgmanite in the Earth’s lower mantle.

  19. Signature splitting in 129Ce

    Institute of Scientific and Technical Information of China (English)

    LIU Ying; WU Xiao-Guang; ZHU Li-Hua; LI Guang-Sheng; HE Chuang-Ye; LI Xue-Qin; PAN Bo; HAO Xin; LI Li-Hua; WANG Zhi-Min; LI Zhong-Yu; XU Qiang

    2009-01-01

    The high spin states of 129Ce have been populated via heavy-ion fusion evaporation reaction 96Mo (37C1, 1p3n) 129Ce. The γ-γ coincidence and intensity balance used to measure the B(M1; I→I-1)/B(E2; I→I-2) (the probability ratio of the dipole and quadrupole transition) in v7/2[523] rotational band of 129Ce. And the energy splitting (Δe') has been got through the experimental Routhians. The lifetimes and quadrupole moments Qt have been extracted from the lineshape analyses using DSAM. The deformation of the v7/2[523] rotational band of 129Ce was extracted from the Qt and moment of inertia JRR.

  20. Method for carbon dioxide splitting

    Energy Technology Data Exchange (ETDEWEB)

    Miller, James E.; Diver, Jr., Richard B.; Siegel, Nathan P.

    2017-02-28

    A method for splitting carbon dioxide via a two-step metal oxide thermochemical cycle by heating a metal oxide compound selected from an iron oxide material of the general formula A.sub.xFe.sub.3-xO.sub.4, where 0.ltoreq.x.ltoreq.1 and A is a metal selected from Mg, Cu, Zn, Ni, Co, and Mn, or a ceria oxide compound of the general formula M.sub.aCe.sub.bO.sub.c, where 0

  1. Salt splitting using ceramic membranes

    Energy Technology Data Exchange (ETDEWEB)

    Kurath, D.E. [Pacific Northwest National Lab., Richland, WA (United States)

    1997-10-01

    Many radioactive aqueous wastes in the DOE complex have high concentrations of sodium that can negatively affect waste treatment and disposal operations. Sodium can decrease the durability of waste forms such as glass and is the primary contributor to large disposal volumes. Waste treatment processes such as cesium ion exchange, sludge washing, and calcination are made less efficient and more expensive because of the high sodium concentrations. Pacific Northwest National Laboratory (PNNL) and Ceramatec Inc. (Salt Lake City UT) are developing an electrochemical salt splitting process based on inorganic ceramic sodium (Na), super-ionic conductor (NaSICON) membranes that shows promise for mitigating the impact of sodium. In this process, the waste is added to the anode compartment, and an electrical potential is applied to the cell. This drives sodium ions through the membrane, but the membrane rejects most other cations (e.g., Sr{sup +2}, Cs{sup +}). The charge balance in the anode compartment is maintained by generating H{sup +} from the electrolysis of water. The charge balance in the cathode is maintained by generating OH{sup {minus}}, either from the electrolysis of water or from oxygen and water using an oxygen cathode. The normal gaseous products of the electrolysis of water are oxygen at the anode and hydrogen at the cathode. Potentially flammable gas mixtures can be prevented by providing adequate volumes of a sweep gas, using an alternative reductant or destruction of the hydrogen as it is generated. As H{sup +} is generated in the anode compartment, the pH drops. The process may be operated with either an alkaline (pH>12) or an acidic anolyte (pH <1). The benefits of salt splitting using ceramic membranes are (1) waste volume reduction and reduced chemical procurement costs by recycling of NaOH; and (2) direct reduction of sodium in process streams, which enhances subsequent operations such as cesium ion exchange, calcination, and vitrification.

  2. Kondo peak splitting and Kondo dip in single molecular magnet junctions

    Energy Technology Data Exchange (ETDEWEB)

    Niu, Pengbin, E-mail: 120233951@qq.com [Institute of Solid State Physics, Shanxi Datong University, Datong 037009 (China); Shi, Yunlong; Sun, Zhu [Institute of Solid State Physics, Shanxi Datong University, Datong 037009 (China); Nie, Yi-Hang [Institute of Theoretical Physics, Shanxi University, Taiyuan 030006 (China); Luo, Hong-Gang [Center for Interdisciplinary Studies & Key Laboratory for Magnetism and Magnetic Materials of the MoE, Lanzhou University, Lanzhou 730000 (China); Beijing Computational Science Research Center, Beijing 100084 (China)

    2016-01-15

    Many factors containing bias, spin–orbit coupling, magnetic fields applied, and so on can strongly influence the Kondo effect, and one of the consequences is Kondo peak splitting (KPS). It is natural that KPS should also appear when another spin degree of freedom is involved. In this work we study the KPS effects of single molecular magnets (SMM) coupled with two metallic leads in low-temperature regime. It is found that the Kondo transport properties are strongly influenced by the exchange coupling and anisotropy of the magnetic core. By employing Green's function method in Hubbard operator representation, we give an analytical expression for local retarded Green's function of SMM and discussed its low-temperature transport properties. We find that the anisotropy term behaves as a magnetic field and the splitting behavior of exchange coupling is quite similar to the spin–orbit coupling. These splitting behaviors are explained by introducing inter-level or intra-level transitions, which account for the seven-peak splitting structure. Moreover, we find a Kondo dip at Fermi level under proper parameters. These Kondo peak splitting behaviors in SMM deepen our understanding to Kondo physics and should be observed in the future experiments. - Highlights: • We study Kondo peak splitting in single molecular magnets. • We study Kondo effect by Hubbard operator Green's function method. • We find Kondo peak splitting structures and a Kondo dip at Fermi level. • The exchange coupling and magnetic anisotropy induce fine splitting structure. • The splitting structures are explained by inter-level or intra-level transitions.

  3. Standard Model Particles from Split Octonions

    Directory of Open Access Journals (Sweden)

    Gogberashvili M.

    2016-01-01

    Full Text Available We model physical signals using elements of the algebra of split octonions over the field of real numbers. Elementary particles are corresponded to the special elements of the algebra that nullify octonionic norms (zero divisors. It is shown that the standard model particle spectrum naturally follows from the classification of the independent primitive zero divisors of split octonions.

  4. Standard Model Particles from Split Octonions

    CERN Document Server

    Gogberashvili, Merab

    2016-01-01

    We model physical signals using elements of the algebra of split octonions over the field of real numbers. Elementary particles are corresponded to the special elements of the algebra that nullify octonionic norms (zero divisors). It is shown that the standard model particle spectrum naturally follows from the classification of the independent primitive zero divisors of split octonions.

  5. Distinguishing division algebras by finite splitting fields

    CERN Document Server

    Krashen, Daniel

    2010-01-01

    This paper is concerned with the problem of determining the number of division algebras which share the same collection of finite splitting fields. As a corollary we are able to determine when two central division algebras may be distinguished by their finite splitting fields over certain fields.

  6. Transferring Goods or Splitting a Resource Pool

    Science.gov (United States)

    Dijkstra, Jacob; Van Assen, Marcel A. L. M.

    2008-01-01

    We investigated the consequences for exchange outcomes of the violation of an assumption underlying most social psychological research on exchange. This assumption is that the negotiated direct exchange of commodities between two actors (pure exchange) can be validly represented as two actors splitting a fixed pool of resources (split pool…

  7. 2-Photon tandem device for water splitting

    DEFF Research Database (Denmark)

    Seger, Brian; Castelli, Ivano Eligio; Vesborg, Peter Christian Kjærgaard;

    2014-01-01

    Within the field Of photocatalytic water splitting there are several strategies to achieve the goal of efficient and cheap photocatalytic water splitting. This work examines one particular strategy by focusing on monolithically stacked, two-photon photoelectrochemical cells. The overall aim of th...

  8. Cheating More when the Spoils Are Split

    Science.gov (United States)

    Wiltermuth, Scott S.

    2011-01-01

    Four experiments demonstrated that people are more likely to cheat when the benefits of doing so are split with another person, even an anonymous stranger, than when the actor alone captures all of the benefits. In three of the studies, splitting the benefits of over-reporting one's performance on a task made such over-reporting seem less…

  9. Split scheduling with uniform setup times.

    NARCIS (Netherlands)

    F. Schalekamp; R.A. Sitters (René); S.L. van der Ster; L. Stougie (Leen); V. Verdugo; A. van Zuylen

    2015-01-01

    htmlabstractWe study a scheduling problem in which jobs may be split into parts, where the parts of a split job may be processed simultaneously on more than one machine. Each part of a job requires a setup time, however, on the machine where the job part is processed. During setup, a

  10. Cheating More when the Spoils Are Split

    Science.gov (United States)

    Wiltermuth, Scott S.

    2011-01-01

    Four experiments demonstrated that people are more likely to cheat when the benefits of doing so are split with another person, even an anonymous stranger, than when the actor alone captures all of the benefits. In three of the studies, splitting the benefits of over-reporting one's performance on a task made such over-reporting seem less…

  11. Stock Splits and Liquidity for Two Major Capital Markets from Central–Eastern Europe

    Directory of Open Access Journals (Sweden)

    Józef Rudnicki

    2012-12-01

    Full Text Available In the stock market there occur some events that contradict the efficient market hypothesis therefore they are called anomalies. One of the mysterious corporate events which has attracted the attention of numerous researchers is a stock split. I perform the review of implications of splitting the stock for market liquidity of companies listed on the Warsaw Stock Exchange and the Vienna Stock Exchange. I use event study, in particular Market model method and Market adjusted return method, to inspect the behavior of abnormal changes in daily trading volume for stock splits performed between 2000 through 2011 over a short run and assuming a longer time interval. Moreover, I juxtapose the results for both stock exchanges to examine whether the stock split phenomenon for two major capital markets from this part of Europe can be better explained by means of existing theories on stock splits. The research is aimed at analyzing the implications of the split for market liquidity, i.e. whether there occurs an immediate effect following the split as well as whether this corporate event improves the level of market liquidity over long run. Furthermore, the goal of the paper is to investigate whether the investors can cash in on the stock split, more specifically, whether they can profit from lower transaction costs. I document a significant growth in the market liquidity of stock splitting firms over 36 months following the split for both capital markets what is indicative of lower transaction costs for investors. The 1–percent significant results are consistent with the liquidity hypothesis on stock splits.

  12. Anisotropic Spin Splitting in Step Quantum Wells

    Institute of Scientific and Technical Information of China (English)

    HAO Ya-Fei; CHEN Yong-Hai; HAO Guo-Dong; WANG Zhan-Guo

    2009-01-01

    By the method of finite difference,the anisotropic spin splitting of the Alx Ga1-x As/GaAs/Aly Ga1-y As/Alx Ga1-x As step quantum wells (QWs) are theoretically investigated considering the interplay of the bulk inversion asymmetry and structure inversion asymmetry induced by step quantum well structure and external electric field.We demonstrate that the anisotropy of the total spin splitting can be controlled by the shape of the QWs and the external electric field.The interface related Rashba effect plays an important effect on the anisotropic spin splitting by influencing the magnitude of the spin splitting and the direction of electron spin.The Rashba spin splitting presents in the step quantum wells due to the interface related Rashba effect even without external electric field or magnetic field.

  13. Crushing or splitting medications: unrecognized hazards.

    Science.gov (United States)

    Gill, Donna; Spain, Margaret; Edlund, Barbara J

    2012-01-01

    Given the high use and the cost of medications in the current economy, one way older adults may save money on prescription costs is to split some of their medications in half. However, not all oral medications can be split. Splitting inappropriate medications such as extended-release tablets can be harmful and in some instances very dangerous. In addition to splitting medications, older adults who have difficulty swallowing pills may resort to crushing the medication for ease of administration. This option is also problematic and potentially harmful if the medication is not intended to be crushed. Clinicians managing the care of older adults need to discuss medication administration, clarify the dosing schedule, and clearly indicate the route of administration. Patients should be cautioned not to split or crush a medication without checking with the health care provider or pharmacist.

  14. Light splitting with imperfect wave plates.

    Science.gov (United States)

    Jackson, Jarom S; Archibald, James L; Durfee, Dallin S

    2017-02-01

    We discuss the use of wave plates with arbitrary retardances, in conjunction with a linear polarizer, to split linearly polarized light into two linearly polarized beams with an arbitrary splitting fraction. We show that for non-ideal wave plates, a much broader range of splitting ratios is typically possible when a pair of wave plates, rather than a single wave plate, is used. We discuss the maximum range of splitting fractions possible with one or two wave plates as a function of the wave plate retardances, and how to align the wave plates to achieve the maximum splitting range possible when simply rotating one of the wave plates while keeping the other one fixed. We also briefly discuss an alignment-free polarization rotator constructed from a pair of half-wave plates.

  15. Iterative group splitting algorithm for opportunistic scheduling systems

    KAUST Repository

    Nam, Haewoon

    2014-05-01

    An efficient feedback algorithm for opportunistic scheduling systems based on iterative group splitting is proposed in this paper. Similar to the opportunistic splitting algorithm, the proposed algorithm adjusts (or lowers) the feedback threshold during a guard period if no user sends a feedback. However, when a feedback collision occurs at any point of time, the proposed algorithm no longer updates the threshold but narrows down the user search space by dividing the users into multiple groups iteratively, whereas the opportunistic splitting algorithm keeps adjusting the threshold until a single user is found. Since the threshold is only updated when no user sends a feedback, it is shown that the proposed algorithm significantly alleviates the signaling overhead for the threshold distribution to the users by the scheduler. More importantly, the proposed algorithm requires a less number of mini-slots than the opportunistic splitting algorithm to make a user selection with a given level of scheduling outage probability or provides a higher ergodic capacity given a certain number of mini-slots. © 2013 IEEE.

  16. Ultrafast reduction of exchange splitting in ferromagnetic nickel

    Science.gov (United States)

    Zhang, G. P.; Bai, Y. H.; George, Thomas F.

    2016-06-01

    A decade ago Rhie et al (2003 Phys. Rev. Lett. 90 247201) reported that when ferromagnetic nickel is subject to an intense ultrashort laser pulse, its exchange splitting is reduced quickly. But to simulate such reduction remains a big challenge. The popular rigid band approximation (RBA), where both the band structure and the exchange splitting are held fixed before and after laser excitation, is unsuitable for this purpose, while the time-dependent density functional theory could be time-consuming. To overcome these difficulties, we propose a time-dependent Liouville and density functional theory (TDLDFT) that integrates the time-dependent Liouville equation into the density functional theory. As a result, the excited charge density is reiterated back into the Kohn-Sham equation, and the band structure is allowed to change dynamically. Even with the ground-state density functional, a larger demagnetization than RBA is found; after we expand Ortenzi’s spin scaling method into an excited-state (laser) density functional, we find that the exchange splitting is indeed strongly reduced, as seen in the experiment. Both the majority and minority bands are shifted toward the Fermi level, but the majority shifts a lot more. The ultrafast reduction in exchange splitting occurs concomitantly with demagnetization. While our current theory is still unable to yield the same percentage loss in the spin moment as observed in the experiment, it predicts a correct trend that agrees with the experiments. With a better functional, we believe that our results can be further improved.

  17. Evaluation of selected information on splitting devices for water samples

    Science.gov (United States)

    Capel, P.D.; Larson, S.J.

    1996-01-01

    Four devices for splitting water samples into representative aliquots are used by the U.S. Geological Survey's Water Resources Division. A thorough evaluation of these devices (14-liter churn, 8-liter churn, plastic cone, and Teflon cone) encompasses a wide variety of concerns, based on both chemical and physical considerations. This report surveys the existing data (as of April 1994) on cleaning efficiency and splitting capability of these devices and presents the data in a systematic framework for evaluation. From the existing data, some of these concerns are adequately or partially addressed, but the majority of concerns could not be addressed because of the lack of data. In general, the existing cleaning and transport protocols are adequate at the milligram per liter level, but the adequacy is largely unknown for trace elements and organic chemicals at lower concen- trations. The existing data indicate that better results are obtained when the splitters are cleaned in the laboratory rather than in the field. Two conclusions that can be reached on the splitting capability of solids are that more work must be done with all four devices to characterize and quantify their limitations and range of usefulness, and that the 14-liter churn (and by association, the 8-liter churn) is not useful in obtaining representative splits of sand-sized particles.

  18. Nuclear Hyperfine and Quadrupole Tensor Characterization of the Nitrogen Hydrogen Bond Donors to the Semiquinone of the QB Site in Bacterial Reaction Centers: A Combined X- and S-Band 14,15N ESEEM and DFT Study

    Science.gov (United States)

    2015-01-01

    The secondary quinone anion radical QB– (SQB) in reaction centers of Rhodobacter sphaeroides interacts with Nδ of His-L190 and Np (peptide nitrogen) of Gly-L225 involved in hydrogen bonds to the QB carbonyls. In this work, S-band (∼3.6 GHz) ESEEM was used with the aim of obtaining a complete characterization of the nuclear quadrupole interaction (nqi) tensors for both nitrogens by approaching the cancelation condition between the isotropic hyperfine coupling and 14N Zeeman frequency at lower microwave frequencies than traditional X-band (9.5 GHz). By performing measurements at S-band, we found a dominating contribution of Nδ in the form of a zero-field nqi triplet at 0.55, 0.92, and 1.47 MHz, defining the quadrupole coupling constant K = e2qQ/4h = 0.4 MHz and associated asymmetry parameter η = 0.69. Estimates of the hyperfine interaction (hfi) tensors for Nδ and Np were obtained from simulations of 1D and 2D 14,15N X-band and three-pulse 14N S-band spectra with all nuclear tensors defined in the SQB g-tensor coordinate system. From simulations, we conclude that the contribution of Np to the S-band spectrum is suppressed by its strong nqi and weak isotropic hfi comparable to the level of hyperfine anisotropy, despite the near-cancelation condition for Np at S-band. The excellent agreement between our EPR simulations and DFT calculations of the nitrogen hfi and nqi tensors to SQB is promising for the future application of powder ESEEM to full tensor characterizations. PMID:24437652

  19. Nuclear hyperfine and quadrupole tensor characterization of the nitrogen hydrogen bond donors to the semiquinone of the QB site in bacterial reaction centers: a combined X- and S-band (14,15)N ESEEM and DFT study.

    Science.gov (United States)

    Taguchi, Alexander T; O'Malley, Patrick J; Wraight, Colin A; Dikanov, Sergei A

    2014-02-13

    The secondary quinone anion radical QB(-) (SQB) in reaction centers of Rhodobacter sphaeroides interacts with Nδ of His-L190 and Np (peptide nitrogen) of Gly-L225 involved in hydrogen bonds to the QB carbonyls. In this work, S-band (∼3.6 GHz) ESEEM was used with the aim of obtaining a complete characterization of the nuclear quadrupole interaction (nqi) tensors for both nitrogens by approaching the cancelation condition between the isotropic hyperfine coupling and (14)N Zeeman frequency at lower microwave frequencies than traditional X-band (9.5 GHz). By performing measurements at S-band, we found a dominating contribution of Nδ in the form of a zero-field nqi triplet at 0.55, 0.92, and 1.47 MHz, defining the quadrupole coupling constant K = e(2)qQ/4h = 0.4 MHz and associated asymmetry parameter η = 0.69. Estimates of the hyperfine interaction (hfi) tensors for Nδ and Np were obtained from simulations of 1D and 2D (14,15)N X-band and three-pulse (14)N S-band spectra with all nuclear tensors defined in the SQB g-tensor coordinate system. From simulations, we conclude that the contribution of Np to the S-band spectrum is suppressed by its strong nqi and weak isotropic hfi comparable to the level of hyperfine anisotropy, despite the near-cancelation condition for Np at S-band. The excellent agreement between our EPR simulations and DFT calculations of the nitrogen hfi and nqi tensors to SQB is promising for the future application of powder ESEEM to full tensor characterizations.

  20. Bad splits in bilateral sagittal split osteotomy: systematic review of fracture patterns.

    Science.gov (United States)

    Steenen, S A; Becking, A G

    2016-07-01

    An unfavourable and unanticipated pattern of the mandibular sagittal split osteotomy is generally referred to as a 'bad split'. Few restorative techniques to manage the situation have been described. In this article, a classification of reported bad split pattern types is proposed and appropriate salvage procedures to manage the different types of undesired fracture are presented. A systematic review was undertaken, yielding a total of 33 studies published between 1971 and 2015. These reported a total of 458 cases of bad splits among 19,527 sagittal ramus osteotomies in 10,271 patients. The total reported incidence of bad split was 2.3% of sagittal splits. The most frequently encountered were buccal plate fractures of the proximal segment (types 1A-F) and lingual fractures of the distal segment (types 2A and 2B). Coronoid fractures (type 3) and condylar neck fractures (type 4) have seldom been reported. The various types of bad split may require different salvage approaches.

  1. Segmented holographic spectrum splitting concentrator

    Science.gov (United States)

    Ayala, Silvana P.; Vorndran, Shelby; Wu, Yuechen; Chrysler, Benjamin; Kostuk, Raymond K.

    2016-09-01

    This paper presents a segmented parabolic concentrator employing holographic spectral filters that provide focusing and spectral bandwidth separation capability to the system. Strips of low band gap silicon photovoltaic (PV) cells are formed into a parabolic surface as shown by Holman et. al. [1]. The surface of the PV segments is covered with holographic elements formed in dichromated gelatin. The holographic elements are designed to transmit longer wavelengths to silicon cells, and to reflect short wavelength light towards a secondary collector where high-bandgap PV cells are mounted. The system can be optimized for different combinations of diffuse and direct solar illumination conditions for particular geographical locations by controlling the concentration ratio and filtering properties of the holographic elements. In addition, the reflectivity of the back contact of the silicon cells is used to increase the optical path length and light trapping. This potentially allows the use of thin film silicon for the low bandgap PV cell material. The optical design combines the focusing properties of the parabolic concentrator and the holographic element to control the concentration ratio and uniformity of the spectral distribution at the high bandgap cell location. The presentation concludes with a comparison of different spectrum splitting holographic filter materials for this application.

  2. Innovative solar thermochemical water splitting.

    Energy Technology Data Exchange (ETDEWEB)

    Hogan, Roy E. Jr.; Siegel, Nathan P.; Evans, Lindsey R.; Moss, Timothy A.; Stuecker, John Nicholas (Robocasting Enterprises, Albuquerque, NM); Diver, Richard B., Jr.; Miller, James Edward; Allendorf, Mark D. (Sandia National Laboratories, Livermore, CA); James, Darryl L. (Texas Tech University, Lubbock, TX)

    2008-02-01

    Sandia National Laboratories (SNL) is evaluating the potential of an innovative approach for splitting water into hydrogen and oxygen using two-step thermochemical cycles. Thermochemical cycles are heat engines that utilize high-temperature heat to produce chemical work. Like their mechanical work-producing counterparts, their efficiency depends on operating temperature and on the irreversibility of their internal processes. With this in mind, we have invented innovative design concepts for two-step solar-driven thermochemical heat engines based on iron oxide and iron oxide mixed with other metal oxides (ferrites). The design concepts utilize two sets of moving beds of ferrite reactant material in close proximity and moving in opposite directions to overcome a major impediment to achieving high efficiency--thermal recuperation between solids in efficient counter-current arrangements. They also provide inherent separation of the product hydrogen and oxygen and are an excellent match with high-concentration solar flux. However, they also impose unique requirements on the ferrite reactants and materials of construction as well as an understanding of the chemical and cycle thermodynamics. In this report the Counter-Rotating-Ring Receiver/Reactor/Recuperator (CR5) solar thermochemical heat engine and its basic operating principals are described. Preliminary thermal efficiency estimates are presented and discussed. Our ferrite reactant material development activities, thermodynamic studies, test results, and prototype hardware development are also presented.

  3. Accurate measurements of electric quadrupole hyperfine interactions of very dilute spins in magnetic solids

    Science.gov (United States)

    Chaplin, D. H.; Hutchison, W. D.; Prandolini, M. J.; Bowden, G. J.

    1998-01-01

    The application of double and triple resonance techniques to enhance signals in quadrupole interaction — nuclear magnetic resonance on oriented nuclei spectroscopy, is illustrated for the antiferromagnet ( 54Mn)MnBr 2-4H 2O. Unusual shifts of the quadrupolar split, higher order, ν ±2, ±1 subresonance, comparable to the NMRON linewidth, are observed and explained.

  4. Calculations with spectroscopic accuracy for energies, transition rates, hyperfine interaction constants, and Landé gJ-factors in nitrogen-like Kr XXX

    Science.gov (United States)

    Wang, K.; Li, S.; Jönsson, P.; Fu, N.; Dang, W.; Guo, X. L.; Chen, C. Y.; Yan, J.; Chen, Z. B.; Si, R.

    2017-01-01

    Extensive self-consistent multi-configuration Dirac-Fock (MCDF) calculations and second-order many-body perturbation theory (MBPT) calculations are performed for the lowest 272 states belonging to the 2s22p3, 2s2p4, 2p5, 2s22p23l, and 2s2p33l (l=s, p, d) configurations of N-like Kr XXX. Complete and consistent data sets of level energies, wavelengths, line strengths, oscillator strengths, lifetimes, AJ, BJ hyperfine interaction constants, Landé gJ-factors, and electric dipole (E1), magnetic dipole (M1), electric quadrupole (E2), magnetic quadrupole (M2) transition rates among all these levels are given. The present MCDF and MBPT results are compared with each other and with other available experimental and theoretical results. The mean relative difference between our two sets of level energies is only about 0.003% for these 272 levels. The accuracy of the present calculations are high enough to facilitate identification of many observed spectral lines. These accurate data can be served as benchmark for other calculations and can be useful for fusion plasma research and astrophysical applications.

  5. Hyperfine-interaction-driven suppression of quantum tunneling at zero field in a holmium(III) single-ion magnet

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Yan-Cong; Liu, Jun-Liang; Chen, Xiao-Ming; Tong, Ming-Liang [Key Lab. of Bioinorganic and Synthetic Chemistry of Ministry of Education, School of Chemistry, Sun Yat-Sen Univ., Guangzhou (China); Wernsdorfer, Wolfgang [Institut Neel, CNRS and Universite Joseph Fournier, Grenoble (France); Institute of Nanotechnology, Karlsruhe Institute of Technology (Germany); Physikalisches Institut, Karlsruhe Institute of Technology (Germany); Liu, Dan; Chibotaru, Liviu F. [Theory of Nanomaterials Group and INPAC-Institute of Nanoscale Physics and Chemistry, Katholieke Universiteit Leuven (Belgium)

    2017-04-24

    An extremely rare non-Kramers holmium(III) single-ion magnet (SIM) is reported to be stabilized in the pentagonal-bipyramidal geometry by a phosphine oxide with a high energy barrier of 237(4) cm{sup -1}. The suppression of the quantum tunneling of magnetization (QTM) at zero field and the hyperfine structures originating from field-induced QTMs can be observed even from the field-dependent alternating-current magnetic susceptibility in addition to single-crystal hysteresis loops. These dramatic dynamics were attributed to the combination of the favorable crystal-field environment and the hyperfine interactions arising from {sup 165}Ho (I=7/2) with a natural abundance of 100 %. (copyright 2017 Wiley-VCH Verlag GmbH and Co. KGaA, Weinheim)

  6. Searching for an oscillating massive scalar field as a dark matter candidate using atomic hyperfine frequency comparisons

    CERN Document Server

    Hees, A; Abgrall, M; Bize, S; Wolf, P

    2016-01-01

    We use six years of accurate hyperfine frequency comparison data of the dual Rubidium and Caesium cold atom fountain FO2 at LNE-SYRTE to search for a massive scalar dark matter candidate. Such a scalar field can induce harmonic variations of the fine structure constant, of the mass of fermions and of the quantum chromodynamic mass scale, which will directly impact the Rubidium/Caesium hyperfine transition frequency ratio. We find no signal consistent with a scalar dark matter candidate but provide improved constraints on the coupling of the putative scalar field to standard matter. Our limits are complementary to previous results that were only sensitive to the fine-structure constant, and improve them by more than an order of magnitude when only a coupling to electromagnetism is assumed.

  7. Searching for an Oscillating Massive Scalar Field as a Dark Matter Candidate Using Atomic Hyperfine Frequency Comparisons

    Science.gov (United States)

    Hees, A.; Guéna, J.; Abgrall, M.; Bize, S.; Wolf, P.

    2016-08-01

    We use 6 yrs of accurate hyperfine frequency comparison data of the dual rubidium and caesium cold atom fountain FO2 at LNE-SYRTE to search for a massive scalar dark matter candidate. Such a scalar field can induce harmonic variations of the fine structure constant, of the mass of fermions, and of the quantum chromodynamic mass scale, which will directly impact the rubidium/caesium hyperfine transition frequency ratio. We find no signal consistent with a scalar dark matter candidate but provide improved constraints on the coupling of the putative scalar field to standard matter. Our limits are complementary to previous results that were only sensitive to the fine structure constant and improve them by more than an order of magnitude when only a coupling to electromagnetism is assumed.

  8. Hyperfine structure effects in Doppler-broadening thermometry on water vapor at 1.4 μm

    Science.gov (United States)

    Domenica De Vizia, Maria; Odintsova, Tatyana; Gianfrani, Livio

    2016-04-01

    This article builds upon a previous work dealing with the budget of uncertainties associated to our recent determination of the Boltzmann constant by means of Doppler broadening thermometry. We report on the outcomes of theoretical calculations and numerical simulations aimed to precisely quantify the influence of the unresolved hyperfine structure of a given ortho component of the \\text{H}218 O spectrum at 1.4 μm on the measurement of the Doppler width of the line itself. We have found that, if the hyperfine structure of the {{4}4,1}\\to {{4}4,0} line of the {ν1}+{ν3} band was ignored, the spectroscopic measurement of the Boltzmann constant would be affected by a relative systematical deviation of 4\\cdot {{10}-8} .

  9. Searching for an Oscillating Massive Scalar Field as a Dark Matter Candidate Using Atomic Hyperfine Frequency Comparisons.

    Science.gov (United States)

    Hees, A; Guéna, J; Abgrall, M; Bize, S; Wolf, P

    2016-08-05

    We use 6 yrs of accurate hyperfine frequency comparison data of the dual rubidium and caesium cold atom fountain FO2 at LNE-SYRTE to search for a massive scalar dark matter candidate. Such a scalar field can induce harmonic variations of the fine structure constant, of the mass of fermions, and of the quantum chromodynamic mass scale, which will directly impact the rubidium/caesium hyperfine transition frequency ratio. We find no signal consistent with a scalar dark matter candidate but provide improved constraints on the coupling of the putative scalar field to standard matter. Our limits are complementary to previous results that were only sensitive to the fine structure constant and improve them by more than an order of magnitude when only a coupling to electromagnetism is assumed.

  10. Self-interaction correction and relativistic exchange on the core states and core hyperfine fields in Fe, Co, and Ni

    Science.gov (United States)

    Severin, L.; Richter, M.; Steinbeck, L.

    1997-04-01

    Local density calculations with self-interaction-corrected core states are reported for the transition-metal ferromagnets Fe, Co, and Ni. The hyperfine field matrix elements have been computed. Good agreement with measurements is obtained for Co, whereas for Fe and Ni the discrepancy between local density theory and experiment remains also in the self-interaction-corrected calculation. Possible changes in the core states due to relativistic exchange corrections are also discussed and found to be of minor importance.

  11. Rotational Spectroscopy of CF_2ClCCl_3 and Analysis of Hyperfine Structure from Four Quadrupolar Nuclei

    Science.gov (United States)

    Kisiel, Zbigniew; Bialkowska-Jaworska, Ewa; Uriarte, Iciar; Basterretxea, Francisco J.; Cocinero, Emilio J.

    2016-06-01

    CF_2ClCCl_3 has recently been identified among several new ozone- depleting substances in the atmosphere. There are no literature reports concerning rotational spectroscopy of this molecule, although we were recently able to report its first chirped pulse, supersonic expansion spectrum. CF_2ClCCl_3 has a rather small dipole moment so that the spectrum is weak and each transition displays very complex nuclear quadrupole hyperfine structure resulting from the presence of four chlorine nuclei. We have presently been able to carry out a complete analysis of the hyperfine structure by combining the information from chirped pulse spectra with dedicated higher resolution measurements made with a cavity supersonic expansion instrument. The hyperfine analysis was carried out with Pickett's SPFIT/SPCAT package and the sizes of Hamiltonian matrices are sufficiently large to require the use of 64-bit compilation of these programs (made available for both Windows and Linux systems on the PROSPE website). The resulting fit is to within experimental accuracy and is supported by ab initio calculations. The precise values of off-diagonal hyperfine constants for all nuclei lead to useful angular information that is complementary to direct structural information from moments of inertia. J.C.Laube, M.J.Newland, C.Hogan, et al., Nature Geoscience 7, 266 (2014). Z.Kisiel, E.Białkowska-Jaworska, L.Pszczółkowski, I.Uriarte, P.Ejica, F.J.Basterretxea, E.J.Cocinero, 70th ISMS, Champaign-Urbana, Illinois, RF-11 (2015). Z.Kisiel, E.Białkowska-Jaworska, L.Pszczółkowski, J.Chem.Phys. 109, 10263 (1998).

  12. Scalar relativistic calculations of hyperfine coupling constants using ab initio density matrix renormalization group method in combination with third-order Douglas-Kroll-Hess transformation: case studies on 4d transition metals.

    Science.gov (United States)

    Nguyen Lan, Tran; Kurashige, Yuki; Yanai, Takeshi

    2015-01-13

    We have developed a new computational scheme for high-accuracy prediction of the isotropic hyperfine coupling constant (HFCC) of heavy molecules, accounting for the high-level electron correlation effects, as well as the scalar-relativistic effects. For electron correlation, we employed the ab initio density matrix renormalization group (DMRG) method in conjunction with a complete active space model. The orbital-optimization procedure was employed to obtain the optimized orbitals required for accurately determining the isotropic HFCC. For the scalar-relativistic effects, we initially derived and implemented the Douglas-Kroll-Hess (DKH) hyperfine coupling operators up to the third order (DKH3) by using the direct transformation scheme. A set of 4d transition-metal radicals consisting of Ag atom, PdH, and RhH2 were chosen as test cases. Good agreement between the isotropic HFCC values obtained from DMRG/DKH3 and experiment was archived. Because there are no available gas-phase values for PdH and RhH2 radicals in the literature, the results from the present high-level theory may serve as benchmark data.

  13. Semi-strong split domination in graphs

    Directory of Open Access Journals (Sweden)

    Anwar Alwardi

    2014-06-01

    Full Text Available Given a graph $G = (V,E$, a dominating set $D subseteq V$ is called a semi-strong split dominating set of $G$ if $|V setminus D| geq 1$ and the maximum degree of the subgraph induced by $V setminus D$ is 1. The minimum cardinality of a semi-strong split dominating set (SSSDS of G is the semi-strong split domination number of G, denoted $gamma_{sss}(G$. In this work, we introduce the concept and prove several results regarding it.

  14. Rotations in the Space of Split Octonions

    Directory of Open Access Journals (Sweden)

    Merab Gogberashvili

    2009-01-01

    Full Text Available The geometrical application of split octonions is considered. The new representation of products of the basis units of split octonionic having David's star shape (instead of the Fano triangle is presented. It is shown that active and passive transformations of coordinates in octonionic “eight-space” are not equivalent. The group of passive transformations that leave invariant the pseudonorm of split octonions is SO(4,4, while active rotations are done by the direct product of O(3,4-boosts and real noncompact form of the exceptional group G2. In classical limit, these transformations reduce to the standard Lorentz group.

  15. Communication: Tunnelling splitting in the phosphine molecule

    Science.gov (United States)

    Sousa-Silva, Clara; Tennyson, Jonathan; Yurchenko, Sergey N.

    2016-09-01

    Splitting due to tunnelling via the potential energy barrier has played a significant role in the study of molecular spectra since the early days of spectroscopy. The observation of the ammonia doublet led to attempts to find a phosphine analogous, but these have so far failed due to its considerably higher barrier. Full dimensional, variational nuclear motion calculations are used to predict splittings as a function of excitation energy. Simulated spectra suggest that such splittings should be observable in the near infrared via overtones of the ν2 bending mode starting with 4ν2.

  16. Splitting Functions at High Transverse Momentum

    CERN Document Server

    Moutafis, Rhea Penelope; CERN. Geneva. TH Department

    2017-01-01

    Among the production channels of the Higgs boson one contribution could become significant at high transverse momentum which is the radiation of a Higgs boson from another particle. This note focuses on the calculation of splitting functions and cross sections of such processes. The calculation is first carried out on the example $e\\rightarrow e\\gamma$ to illustrate the way splitting functions are calculated. Then the splitting function of $e\\rightarrow eh$ is calculated in similar fashion. This procedure can easily be generalized to processes such as $q\\rightarrow qh$ or $g\\rightarrow gh$.

  17. Tunnelling splitting in the phosphine molecule

    CERN Document Server

    Sousa-Silva, Clara; Yurchenko, Sergey N

    2016-01-01

    Splitting due to tunnelling via the potential energy barrier has played a significant role in the study of molecular spectra since the early days of spectroscopy. The observation of the ammonia doublet led to attempts to find a phosphine analogous, but these have so far failed due to its considerably higher barrier. Full dimensional, variational nuclear motion calculations are used to predict splittings as a function of excitation energy. Simulated spectra suggest that such splittings should be observable in the near infrared via overtones of the $\

  18. Spin relaxation of positive trions in InAs/GaAs quantum dots: the role of hyperfine interaction

    Energy Technology Data Exchange (ETDEWEB)

    Braun, Pierre-Francois; Lombez, Laurent; Urbaszek, Bernhard; Marie, Xavier; Amand, Thierry; Renucci, Pierre [Laboratoire de Nanophysique Magnetisme et Optoelectronique, INSA, 31077 Toulouse Cedex 4 (France); Eble, Benoit; Krebs, Olivier; Lemaitre, Aristide; Voisin, Paul [CNRS-Laboratoire de Photonique et Nanostructures, Route de Nozay, 91460 Marcoussis (France); Kalevich, Vladimir K.; Kavokin, Kyrill V. [Ioffe Physico-Technical Institute, St. Petersburg 194021 (Russian Federation)

    2006-12-15

    We report on positive trion (X{sup +}) spin relaxation in self-assembled InAs/GaAs quantum dots. The hyperfine interaction between the electron and nuclear spins acts as a randomly oriented magnetic field for the electron spin, giving rise to ensemble dephasing and thus to partial relaxation in less than 1 ns. Time-resolved photoluminescence polarization measurements carried out on an ensemble of InAs/GaAs quantum dots, charged with excess holes by proximity p-doping, reveal this peculiar dynamics. The fast polarization decrease can be efficiently suppressed by screening the hyperfine interaction with a longitudinal magnetic field of 100 mT. The quenching of this hyperfine-induced relaxation is also evidenced for a single charge-tunable quantum dot in the regime of X{sup +} photoluminescence and excited with modulated polarization to prevent dynamic nuclear polarization. (copyright 2006 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

  19. A novel shape transformation of Fe MgO nanocomposites: microstructural, magnetic and hyperfine investigations

    Science.gov (United States)

    Mukherjee, S.; Kumar, S.; Das, D.

    2007-08-01

    Fe-MgO nanocomposites synthesized by the mechanical high-energy transfer technique were characterized by x-ray diffraction (XRD), transmission electron microscopy, Mössbauer spectroscopy and dc magnetization studies. By varying the duration of milling, powder with different grain sizes in the range 17-40 nm was produced. XRD and Mössbauer measurements could not detect the presence of any form of iron oxide in the nanocomposites. Transmission electron micrographs showed a shape transformation from spherical to acicular-like geometry in the samples ball milled for more than 36 h. Dc magnetization measurements show an increase in the coercive field with decrease in average grain size, with a sharp increase at the point of shape transformation. A marked decrease from the expected values of saturation magnetization and magnetic moment per formula unit was observed. This decrease was ascribed to the magnetic dead layer formed at the surface of the nanoparticles, which increased with the increase in milling time. The nanocomposites ball milled for more than 36 h exhibit a two-component Mössbauer spectra due to the presence of two phases: a crystalline phase and an additional phase corresponding to the atoms residing at the grain boundaries between the crystallites. The grain boundaries give rise to a distribution of hyperfine magnetic fields, typical of an amorphous-like compound.

  20. A novel shape transformation of Fe-MgO nanocomposites: microstructural, magnetic and hyperfine investigations

    Energy Technology Data Exchange (ETDEWEB)

    Mukherjee, S [UGC-DAE Consortium for Scientific Research, Kolkata Centre III/LB-8, Bidhannagar, Kolkata 700 098 (India); Kumar, S [Department of Physics, Jadavpur University, Kolkata 700 032 (India); Das, D [UGC-DAE Consortium for Scientific Research, Kolkata Centre III/LB-8, Bidhannagar, Kolkata 700 098 (India)

    2007-08-07

    Fe-MgO nanocomposites synthesized by the mechanical high-energy transfer technique were characterized by x-ray diffraction (XRD), transmission electron microscopy, Moessbauer spectroscopy and dc magnetization studies. By varying the duration of milling, powder with different grain sizes in the range 17-40 nm was produced. XRD and Moessbauer measurements could not detect the presence of any form of iron oxide in the nanocomposites. Transmission electron micrographs showed a shape transformation from spherical to acicular-like geometry in the samples ball milled for more than 36 h. Dc magnetization measurements show an increase in the coercive field with decrease in average grain size, with a sharp increase at the point of shape transformation. A marked decrease from the expected values of saturation magnetization and magnetic moment per formula unit was observed. This decrease was ascribed to the magnetic dead layer formed at the surface of the nanoparticles, which increased with the increase in milling time. The nanocomposites ball milled for more than 36 h exhibit a two-component Moessbauer spectra due to the presence of two phases: a crystalline phase and an additional phase corresponding to the atoms residing at the grain boundaries between the crystallites. The grain boundaries give rise to a distribution of hyperfine magnetic fields, typical of an amorphous-like compound.

  1. Quantum control of the hyperfine-coupled electron and nuclear spins in alkali-metal atoms

    Science.gov (United States)

    Merkel, Seth T.; Jessen, Poul S.; Deutsch, Ivan H.

    2008-08-01

    We study quantum control of the full hyperfine manifold in the ground-electronic state of alkali-metal atoms based on applied radio frequency and microwave fields. Such interactions should allow essentially decoherence-free dynamics and the application of techniques for robust control developed for NMR spectroscopy. We establish the conditions under which the system is controllable in the sense that one can generate an arbitrary unitary map on the system. We apply this to the case of Cs133 with its d=16 dimensional Hilbert space of magnetic sublevels in the 6S1/2 state, and design control wave forms that generate an arbitrary target state from an initial fiducial state. We develop a generalized Wigner function representation for this space consisting of the direct sum of two irreducible representations of SU(2), allowing us to visualize these states. The performance of different control scenarios is evaluated based on the ability to generate a high-fidelity operation in an allotted time with the available resources. We find good operating points commensurate with modest laboratory requirements.

  2. Quiet Sun Magnetic Field Measurements Based on Lines with Hyperfine Structure

    CERN Document Server

    Almeida, J Sanchez; Degl'Innocenti, E Landi; Berrilli, F

    2007-01-01

    The Zeeman pattern of MnI lines is sensitive to hyperfine structure (HFS) and, they respond to hG magnetic field strengths differently from the lines used in solar magnetometry. This peculiarity has been employed to measure magnetic field strengths in quiet Sun regions. However, the methods applied so far assume the magnetic field to be constant in the resolution element. The assumption is clearly insufficient to describe the complex quiet Sun magnetic fields, biasing the results of the measurements. We present the first syntheses of MnI lines in realistic quiet Sun model atmospheres. The syntheses show how the MnI lines weaken with increasing field strength. In particular, kG magnetic concentrations produce NnI 5538 circular polarization signals (Stokes V) which can be up to two orders of magnitude smaller than the weak magnetic field approximation prediction. Consequently, (1) the polarization emerging from an atmosphere having weak and strong fields is biased towards the weak fields, and (2) HFS features c...

  3. Isotope Effect in Organic Magneto-Transport; the Role of Hyperfine Interaction

    Science.gov (United States)

    Nguyen, Tho

    2010-03-01

    Organic semiconductors have been used as active layer in devices such as organic light-emitting diodes, photovoltaic cells, and field-effect transistors. Recently there has been a growing interest in spin and magnetic field effects (MFE) in these materials. This include optically detected magnetic resonance (ODMR), where long spin coherence time was demonstrated; organic light emitting diodes (OLED), where substantive magneto-electroluminescence and magneto-conductance were obtained; and organic spin valves (OSV), where spin injection from ferromagnetic electrodes was verified. The interest in organic semiconductors has been motivated by the weak spin-orbit interaction that is caused by the light building block elements such as carbon and hydrogen. However, the role of the hyperfine interaction (HFI) between the injected spin-.5ex1 -.1em/ -.15em.25ex2 carriers and various nuclear spins in organic magneto-transport has not been experimentally tested. Using the chemical versatility advantage of the organics, we studied and compare the magnetic-field effects in films, OLED and OSV devices based on polymers made of protonated, H-, and deuterated, D-hydrogen having a weaker HFI strength. We demonstrate that the HFI indeed plays a crucial role in all three magnetic-field effects. OLEDs [films] based on the D-polymers show substantial narrower MFE [ODMR] response; whereas due to the longer measured spin diffusion, OSV devices based on D-polymers show substantially larger magnetoresistance response.

  4. Leggett-Garg inequalities violation via the Fermi contact hyperfine interaction

    Energy Technology Data Exchange (ETDEWEB)

    Lobejko, Marcin; Dajka, Jerzy [Institute of Physics, University of Silesia, Katowice (Poland); Silesian Center for Education and Interdisciplinary Research, University of Silesia, Chorzow (Poland)

    2017-06-15

    In this paper we examine theoretically how the spin-spin interaction between a nuclei and an electron in the atom affects violation of the Leggett-Garg inequalities. We consider the simplest case of atoms in the {sup 2}S{sub 1/2} state that in the valence shell have just a single electron and the evolution in time of the spin is dictated only by the Fermi contact hyperfine interaction. We found that for special initial conditions and a particular measured observable the high spin nucleus couple to the valence electron such that violation of Leggett-Garg inequalities increases with total spin of states. Consequently, our results show that for the Hydrogen, the smallest atom in Nature, the violation of the Leggett-Garg inequalities is the smallest whereas for the largest atom, the Cesium, the violation is the largest. Moreover, this violation does not depend on a principal quantum number, thus our model can be used for Rydberg atoms in order to test macrorealism for 'almost macroscopic' objects. (copyright 2016 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  5. Unravelling the local structure of topological crystalline insulators using hyperfine interactions

    CERN Multimedia

    Phenomena emerging from relativistic electrons in solids have become one the main topical subjects in condensed matter physics. Among a wealth of intriguing new phenomena, several classes of materials have emerged including graphene, topological insulators and Dirac semi-metals. This project is devoted to one such class of materials, in which a subtle distortion of the crystalline lattice drives a material through different topological phases: Z$_{2}$ topological insulator (Z$_{2}$-TI), topological crystalline insulator (TCI), or ferroelectric Rashba semiconductor (FERS). We propose to investigate the local structure of Pb$_{1-x}$Sn$_{x}$Te and Ge$_{1-x}$Sn$_{x}$Te (with $\\textit{x}$ from 0 to 1) using a combination of experimental techniques based on hyperfine interactions: emission Mössbauer spectroscopy (eMS) and perturbed angular correlation spectroscopy (PAC). In particular, we propose to study the effect of composition ($\\textit{x}$ in Pb$_{1-x}$Sn$_{x}$Te and Ge$_{1-x}$Sn$_{x}$Te) on: \\\\ \\\\(1) the mag...

  6. Estimating the hyperfine coupling parameters of the avian compass by comprehensively considering the available experimental results

    Science.gov (United States)

    Xu, Bao-Ming; Zou, Jian; Li, Jun-Gang; Shao, Bin

    2013-09-01

    Migratory birds can utilize the geomagnetic field for orientation and navigation through a widely accepted radical-pair mechanism. Although many theoretical works have been done, the available experimental results have not been fully considered, especially the temporary disorientation induced by the field which is increased by 30% of the geomagnetic field and the disorientation of the very weak resonant field of 15 nT. In this paper, we consider the monotonicity of the singlet yield angular profile as the prerequisite of direction sensitivity, and find that for some optimal values of the hyperfine coupling parameters (that is, the order of 10-7˜10-6 meV) the experimental results available so far can be satisfied. We also investigate the effects of two decoherence environments and demonstrate that, in order to satisfy the available experimental results, the decoherence rate should be lower than the recombination rate. Finally, we investigate the effects of the fluctuating magnetic noises and find that the vertical noise destroys the monotonicity of the profile completely, but the parallel noise preserves the monotonicity perfectly and even can enhance the direction sensitivity.

  7. Transmission integral analysis of Mössbauer spectra displaying hyperfine parameter distributions with arbitrary profile

    Energy Technology Data Exchange (ETDEWEB)

    Klencsár, Zoltán, E-mail: z.klencsar@mosswinn.hu [Pitvar u. 11., Budapest 1141 (Hungary)

    2014-10-27

    Accurate quantitative analysis of Mössbauer spectra displaying thickness effects requires the consideration of the so-called transmission integral when modeling the spectral shape. Whereas this is straightforward when the correct model for the decomposition of the absorber's nuclear resonance absorption cross-section into individual components is a priori known, in the absence of such knowledge and notably in the presence of hyperfine parameter distributions with an unknown profile, the so-called model-independent evaluation methods could be used to fit the spectra. However, the methods available for this purpose were developed for the analysis of spectra for which the thin absorber approximation is valid, and thus they do not take the sample thickness and related effects into account. Consequently, in order to use them for spectra displaying thickness effects, their usage needs to be generalized by combining them with transmission integral fitting. A new algorithm realizing such a generalized version of the Hesse-Rübartsch model-independent evaluation method was developed recently as an integral part of the MossWinn program. In the present work, the working principle of the newly developed algorithm is described in details along with examples illustrating the capabilities of the method for the case of {sup 57}Fe Mössbauer spectroscopy.

  8. Sternheimer free determination of the 51V nuclear quadrupole moment from hyperfine structure measurements

    Science.gov (United States)

    Unkel, P.; Buch, P.; Dembczyński, J.; Ertmer, W.; Johann, U.

    1989-12-01

    The hyperfine structure (hfs) of 18 metastable states of51V has been measured by laser induced fluorescence. 15 of these states have been measured additionally very precisely by the ABMR-LIRF method. Using results of earlier hfs measurements, the hfs of altogether 33 fine structure states is analyzed using a method of simultaneous parametrization of one- and two-body interactions in the atomic hfs of the model space 3 d 3 + M 4 s 2 - M ( M = 0, 1, 2). The hfs of these states is described by 16 parameters for the magnetic dipole interaction and 12 parameters for the electric quadrupole interaction. From these model space parameters corresponding configuration dependent parameters for the three configurations were determined. These parameters allow a prediction of the hfs constants of all states of the modelspace within an accuracy of 5 to 10%. The evaluation of the nuclear quadrupole moment of51V, free of Sternheimer corrections up to second order, yielded the value of -0.043(5) barn.

  9. A Novel Split and Merge Technique for Hypertext Classification

    Science.gov (United States)

    Saha, Suman; Murthy, C. A.; Pal, Sankar K.

    As web grows at an increasing speed, hypertext classification is becoming a necessity. While the literature on text categorization is quite mature, the issue of utilizing hypertext structure and hyperlinks has been relatively unexplored. In this paper, we introduce a novel split and merge technique for classification of hypertext documents. The splitting process is performed at the feature level by representing the hypertext features in a tensor space model. We exploit the local-structure and neighborhood recommendation encapsulated in the this representation model. The merging process is performed on multiple classifications obtained from split representation. A meta level decision system is formed by obtaining predictions of base level classifiers trained on different components of the tensor and actual category of the hypertext document. These individual predictions for each component of the tensor are subsequently combined to a final prediction using rough set based ensemble classifiers. Experimental results of classification obtained by using our method is marginally better than other existing hypertext classification techniques.

  10. Beyond the Interconnections: Split Manufacturing in RF Designs

    Directory of Open Access Journals (Sweden)

    Yu Bi

    2015-08-01

    Full Text Available With the globalization of the integrated circuit (IC design flow of chip fabrication, intellectual property (IP piracy is becoming the main security threat. While most of the protection methods are dedicated for digital circuits, we are trying to protect radio-frequency (RF designs. For the first time, we applied the split manufacturing method in RF circuit protection. Three different implementation cases are introduced for security and design overhead tradeoffs, i.e., the removal of the top metal layer, the removal of the top two metal layers and the design obfuscation dedicated to RF circuits. We also developed a quantitative security evaluation method to measure the protection level of RF designs under split manufacturing. Finally, a simple Class AB power amplifier and a more sophisticated Class E power amplifier are used for the demonstration through which we prove that: (1 the removal of top metal layer or the top two metal layers can provide high-level protection for RF circuits with a lower request to domestic foundries; (2 the design obfuscation method provides the highest level of circuit protection, though at the cost of design overhead; and (3 split manufacturing may be more suitable for RF designs than for digital circuits, and it can effectively reduce IP piracy in untrusted off-shore foundries.

  11. Splitting of IVP bovine blastocyst affects morphology and gene expression of resulting demi-embryos during in vitro culture and in vivo elongation.

    Science.gov (United States)

    Velasquez, Alejandra E; Castro, Fidel O; Veraguas, Daniel; Cox, Jose F; Lara, Evelyn; Briones, Mario; Rodriguez-Alvarez, Lleretny

    2016-02-01

    Embryo splitting might be used to increase offspring yield and for molecular analysis of embryo competence. How splitting affects developmental potential of embryos is unknown. This research aimed to study the effect of bovine blastocyst splitting on morphological and gene expression homogeneity of demi-embryos and on embryo competence during elongation. Grade I bovine blastocyst produced in vitro were split into halves and distributed in nine groups (3 × 3 setting according to age and stage before splitting; age: days 7-9; stage: early, expanded and hatched blastocysts). Homogeneity and survival rate in vitro after splitting (12 h, days 10 and 13) and the effect of splitting on embryo development at elongation after embryo transfer (day 17) were assessed morphologically and by RT-qPCR. The genes analysed were OCT4, SOX2, NANOG, CDX2, TP1, TKDP1, EOMES, and BAX. Approximately 90% of split embryos had a well conserved defined inner cell mass (ICM), 70% of the halves had similar size with no differences in gene expression 12 h after splitting. Split embryos cultured further conserved normal and comparable morphology at day 10 of development; this situation changes at day 13 when embryo morphology and gene expression differed markedly among demi-embryos. Split and non-split blastocysts were transferred to recipient cows and were recovered at day 17. Fifty per cent of non-split embryos were larger than 100 mm (33% for split embryos). OCT4, SOX2, TP1 and EOMES levels were down-regulated in elongated embryos derived from split blastocysts. In conclusion, splitting day-8 blastocysts yields homogenous demi-embryos in terms of developmental capability and gene expression, but the initiation of the filamentous stage seems to be affected by the splitting.

  12. Electroweak Splitting Functions and High Energy Showering

    CERN Document Server

    Chen, Junmou; Tweedie, Brock

    2016-01-01

    We derive the electroweak (EW) collinear splitting functions for the Standard Model, including the massive fermions, gauge bosons and the Higgs boson. We first present the splitting functions in the limit of unbroken SU(2)xU(1) and discuss their general features in the collinear and soft-collinear regimes. We then systematically incorporate EW symmetry breaking (EWSB), which leads to the emergence of additional "ultra-collinear" splitting phenomena and naive violations of the Goldstone-boson Equivalence Theorem. We suggest a particularly convenient choice of non-covariant gauge (dubbed "Goldstone Equivalence Gauge") that disentangles the effects of Goldstone bosons and gauge fields in the presence of EWSB, and allows trivial book-keeping of leading power corrections in the VEV. We implement a comprehensive, practical EW showering scheme based on these splitting functions using a Sudakov evolution formalism. Novel features in the implementation include a complete accounting of ultra-collinear effects, matching...

  13. Supramolecular Control over Split-Luciferase Complementation.

    Science.gov (United States)

    Bosmans, Ralph P G; Briels, Jeroen M; Milroy, Lech-Gustav; de Greef, Tom F A; Merkx, Maarten; Brunsveld, Luc

    2016-07-25

    Supramolecular split-enzyme complementation restores enzymatic activity and allows for on-off switching. Split-luciferase fragment pairs were provided with an N-terminal FGG sequence and screened for complementation through host-guest binding to cucurbit[8]uril (Q8). Split-luciferase heterocomplex formation was induced in a Q8 concentration dependent manner, resulting in a 20-fold upregulation of luciferase activity. Supramolecular split-luciferase complementation was fully reversible, as revealed by using two types of Q8 inhibitors. Competition studies with the weak-binding FGG peptide revealed a 300-fold enhanced stability for the formation of the ternary heterocomplex compared to binding of two of the same fragments to Q8. Stochiometric binding by the potent inhibitor memantine could be used for repeated cycling of luciferase activation and deactivation in conjunction with Q8, providing a versatile module for in vitro supramolecular signaling networks.

  14. Irrational beliefs, attitudes about competition, and splitting.

    Science.gov (United States)

    Watson, P J; Morris, R J; Miller, L

    2001-03-01

    Rational-Emotive Behavior Therapy (REBT) theoretically promotes actualization of both individualistic and social-oriented potentials. In a test of this assumption, the Belief Scale and subscales from the Survey of Personal Beliefs served as measures of what REBT presumes to be pathogenic irrationalities. These measures were correlated with the Hypercompetitive Attitude Scale (HCAS), the Personal Development Competitive Attitude Scale (PDCAS), factors from the Splitting Index, and self-esteem. Results for the HCAS and Self-Splitting supported the REBT claim about individualistic self-actualization. Mostly nonsignificant and a few counterintuitive linkages were observed for irrational beliefs with the PDCAS, Family-Splitting, and Other-Splitting, and these data suggested that REBT may be less successful in capturing the "rationality" of a social-oriented self-actualization.

  15. Split Brain Theory: Implications for Nurse Educators.

    Science.gov (United States)

    de Meneses, Mary

    1980-01-01

    Discusses incorporating nontraditional concepts of learning in nursing education. Elements explored include the split brain theory, school design, teaching styles, teacher's role, teaching strategies, adding variety to the curriculum, and modular learning. (CT)

  16. Agreeing with subjects in number: The rare split of Amuzgo verbal inflection

    OpenAIRE

    Palancar, Enrique L.; Feist, Timothy

    2015-01-01

    International audience; Verbs in San Pedro Amuzgo, an Oto Manguean language of Mexico, often have two different stems in the paradigm, one used with singular subjects and the other with plural subjects. This constitutes a split motivated by number which is typologically interesting due to its rarity, since number splits are commonly only associated with the S and the O arguments, but not S and A as subject. Apart from at stem level, the split is also manifested in the incompletive of an infle...

  17. Observations of Autler-Townes spatial splitting of four-wave mixing image

    Science.gov (United States)

    Huang, Gaoping; Sun, Jia; Feng, Weikang; Yuan, Jiamin; Wu, Zhenkun; Qin, Mengzhe; Zhang, Yiqi; Zhang, Yanpeng

    2013-08-01

    We report the self- and external-dressed Autler-Townes (A-T) splittings of the images of the generated four-wave mixing signal (FWM) and electromagnetically induced transparency (EIT) of probe images in cascade three-level atomic system. Such spatial properties of probe and FWM signals are induced by the enhanced cross-Kerr nonlinearity. We demonstrate the controlled electromagnetically induced spatial dispersion (EISD), splitting and focusing of probe and FWM signals images by adjusting self- and external-dressing fields. Studies on such controllable A-T spatial splitting and spatial EIT effect can be very useful in applications of spatial signal processing and optical communication.

  18. Ray splitting in paraxial optical cavities

    CERN Document Server

    Puentes, G; Woerdman, J P

    2003-01-01

    We present a numerical investigation of the ray dynamics in a paraxial optical cavity when a ray splitting mechanism is present. The cavity is a conventional two-mirror stable resonator and the ray splitting is achieved by inserting an optical beam splitter perpendicular to the cavity axis. We show that depending on the position of the beam splitter the optical resonator can become unstable and the ray dynamics displays a positive Lyapunov exponent.

  19. Antenna Splitting Functions for Massive Particles

    Energy Technology Data Exchange (ETDEWEB)

    Larkoski, Andrew J.; Peskin, Michael E.; /SLAC

    2011-06-22

    An antenna shower is a parton shower in which the basic move is a color-coherent 2 {yields} 3 parton splitting process. In this paper, we give compact forms for the spin-dependent antenna splitting functions involving massive partons of spin 0 and spin 1/2. We hope that this formalism we have presented will be useful in describing the QCD dynamics of the top quark and other heavy particles at LHC.

  20. Laser beam splitting by polarization encoding.

    Science.gov (United States)

    Wan, Chenhao

    2015-03-20

    A scheme is proposed to design a polarization grating that splits an incident linearly polarized beam to an array of linearly polarized beams of identical intensity distribution and various azimuth angles of linear polarization. The grating is equivalent to a wave plate with space-variant azimuth angle and space-variant phase retardation. The linear polarization states of all split beams make the grating suitable for coherent beam combining architectures based on Dammann gratings.