Dielectric properties in the vicinity of the ferroelectric phase transition in a mixed crystal of deuterated betaine phosphate{sub 0.03} betaine phosphite{sub 0.97}

Energy Technology Data Exchange (ETDEWEB)

Banys, J.; Macutkevic, J.; Kajokas, A.; Brilingas, A.; Grigas, J. [Faculty of Physics, Vilnius University, Sauletekio 9, Vilnius 2040 (Lithuania); Klimm, C.; Voelkel, G. [Fakultaet fuer Physik und Geowissenschaften, Universitaet Leipzig, Linnestr. 5, 04103 Leipzig (Germany)

2004-02-01

The dielectric behaviour of ferroelectric hydrogen bonded deuterated betaine phosphate{sub 0.03} betaine phosphite{sub 0.97} (DBP{sub 0.03}DBPI{sub 0.97})is investigated in the region of the ferroelectric phase transition. Dielectric dispersion is investigated in the frequency range up to 12 GHz. The dielectric dynamics shows a critical slowing down. The frequency of the relaxational soft mode in the paraelectric phase varies according to the quasi-one-dimensional Ising model and decreases up to 0.31 GHz at the phase transition temperature (T{sub C}=272 K). The obtained activation energy for the deuteron flipping motion {delta}U=2.3kT{sub C}=0.054 eV shows the order-disorder character of the ferroelectric phase transition. The spontaneous polarisation, obtained from pyroelectric measurements, is also well explained using the quasi-one-dimensional Ising model. At low temperatures, the freezing phenomena in DBP{sub 0.03}DBPI{sub 0.97} revealed the complex dielectric permittivity behaviour characteristic for the transition into the dipolar glass state. The activation energy of this low temperature process was found to be E{sub b}=1297 K (0.041 eV) and the glass temperature was estimated to 73 K. (copyright 2004 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

Anion Redox Chemistry in the Cobalt Free 3d Transition Metal Oxide Intercalation Electrode Li[Li0.2Ni0.2Mn0.6]O2.

Science.gov (United States)

Luo, Kun; Roberts, Matthew R; Guerrini, Niccoló; Tapia-Ruiz, Nuria; Hao, Rong; Massel, Felix; Pickup, David M; Ramos, Silvia; Liu, Yi-Sheng; Guo, Jinghua; Chadwick, Alan V; Duda, Laurent C; Bruce, Peter G

2016-09-07

Conventional intercalation cathodes for lithium batteries store charge in redox reactions associated with the transition metal cations, e.g., Mn(3+/4+) in LiMn2O4, and this limits the energy storage of Li-ion batteries. Compounds such as Li[Li0.2Ni0.2Mn0.6]O2 exhibit a capacity to store charge in excess of the transition metal redox reactions. The additional capacity occurs at and above 4.5 V versus Li(+)/Li. The capacity at 4.5 V is dominated by oxidation of the O(2-) anions accounting for ∼0.43 e(-)/formula unit, with an additional 0.06 e(-)/formula unit being associated with O loss from the lattice. In contrast, the capacity above 4.5 V is mainly O loss, ∼0.08 e(-)/formula. The O redox reaction involves the formation of localized hole states on O during charge, which are located on O coordinated by (Mn(4+)/Li(+)). The results have been obtained by combining operando electrochemical mass spec on (18)O labeled Li[Li0.2Ni0.2Mn0.6]O2 with XANES, soft X-ray spectroscopy, resonant inelastic X-ray spectroscopy, and Raman spectroscopy. Finally the general features of O redox are described with discussion about the role of comparatively ionic (less covalent) 3d metal-oxygen interaction on anion redox in lithium rich cathode materials.

arXiv Measurement of the $\\pi^0$ electromagnetic transition form factor slope

CERN Document Server

Lazzeroni, C.; Romano, A.; Blazek, T.; Koval, M.; Ceccucci, A.; Danielsson, H.; Falaleev, V.; Gatignon, L.; Goy Lopez, S.; Hallgren, B.; Maier, A.; Peters, A.; Piccini, M.; Riedler, P.; Frabetti, P.L.; Gersabeck, E.; Kekelidze, V.; Madigozhin, D.; Misheva, M.; Molokanova, N.; Movchan, S.; Potrebenikov, Yu.; Shkarovskiy, S.; Zinchenko, A.; Rubin, P.; Baldini, W.; Cotta Ramusino, A.; Dalpiaz, P.; Fiorini, M.; Gianoli, A.; Norton, A.; Petrucci, F.; Savrié, M.; Wahl, H.; Bizzeti, A.; Bucci, F.; Iacopini, E.; Lenti, M.; Veltri, M.; Antonelli, A.; Moulson, M.; Raggi, M.; Spadaro, T.; Eppard, K.; Hita-Hochgesand, M.; Kleinknecht, K.; Renk, B.; Wanke, R.; Winhart, A.; Winston, R.; Bolotov, V.; Duk, V.; Gushchin, E.; Ambrosino, F.; Di Filippo, D.; Massarotti, P.; Napolitano, M.; Palladino, V.; Saracino, G.; Anzivino, G.; Imbergamo, E.; Piandani, R.; Sergi, A.; Cenci, P.; Pepe, M.; Costantini, F.; Doble, N.; Giudici, S.; Pierazzini, G.; Sozzi, M.; Venditti, S.; Balev, S.; Collazuol, G.; DiLella, L.; Gallorini, S.; Goudzovski, E.; Lamanna, G.; Mannelli, I.; Ruggiero, G.; Cerri, C.; Fantechi, R.; Kholodenko, S.; Kurshetsov, V.; Obraztsov, V.; Semenov, V.; Yushchenko, O.; D'Agostini, G.; Leonardi, E.; Serra, M.; Valente, P.; Fucci, A.; Salamon, A.; Bloch-Devaux, B.; Peyaud, B.; Engelfried, J.; Coward, D.; Kozhuharov, V.; Litov, L.; Arcidiacono, R.; Bifani, S.; Biino, C.; Dellacasa, G.; Marchetto, F.; Numao, T.; Retière, F.

2017-05-10

The NA62 experiment collected a large sample of charged kaon decays in 2007 with a highly efficient trigger for decays into electrons. A measurement of the $\\pi^{0}$ electromagnetic transition form factor slope parameter from $1.11\\times10^{6}$ fully reconstructed $K^\\pm \\to \\pi^\\pm \\pi^0_D, \\; \\pi^0_D \\to e^+ e^- \\, \\gamma$ events is reported. The measured value $a = \\left(3.68 \\pm 0.57\\right)\\times 10^{-2}$ is in good agreement with theoretical expectations and previous measurements, and represents the most precise experimental determination of the slope in the time-like momentum transfer region.

Magnetic phase transition in MnFeP0.5As0.4Si0.1

International Nuclear Information System (INIS)

Wang, J L; Campbell, S J; Tegus, O; Brueck, E; Dou, S X

2010-01-01

We have carried out a detailed investigation of the magnetic phase transition in MnFeP 0.5 As 0.4 Si 0.1 . Temperature hysteresis has been observed in the variable temperature magnetization curves (B appl = 0.01 T) with T C W ∼ 302 K on warming and T C C ∼ 292 K on cooling. The first order nature of this transition in MnFeP 0.5 As 0.4 Si 0.1 is confirmed by the negative slope obtained from isotherms of M 2 versus B/M around the critical temperature. Linear thermal expansion measurements reveal a large volume change, ΔV/V∼8.7x10 -3 at the magnetic phase transition and that this magnetovolume effect is suppressed to ΔV/V ∼ 5.5x10 -3 in an applied field of B appl = 1.0 T. Analyses of 57 Fe Moessbauer spectra (4.5 - 300 K) using a random distribution model and taking nearest-neighbour environments into account, indicate that the paramagnetic and ferromagnetic phases coexist over a temperature range of ∼ 45 K around the Curie temperature. The Debye temperature for MnFeP 0.5 As 0.4 Si 0.1 has been evaluated as θ D = 350 ± 20 K from the temperature dependence of the average isomer shift.

Absolute M1 and E2 Transition Probabilities in 233U

International Nuclear Information System (INIS)

Malmskog, S.G.; Hoejeberg, M.

1967-08-01

Using the delayed coincidence technique, the following half lives have been determined for different excited states in 233 U: T 1/2 (311.9 keV level) = (1.20 ± 0.15) x 10 -10 sec, T 1/2 (340.5 keV level) = (5.2 ± 1.0) x 10 -11 sec, T 1/2 (398.6 keV level) = (5.5 ± 2.0) x 10 -11 sec and T 1/2 (415.8 keV level) -11 sec. From these half life determinations, together with earlier known electron intensities and conversion coefficients, 22 reduced B(Ml) and B(E2) transition probabilities (including 9 limits) have been deduced. The rotational transitions give information on the parameters δ and (g K - g R ) . The experimental M1 and E2 transition rates between members of different bands have been analysed in terms of the predictions of the Nilsson model, taking also pairing correlations and Coriolis coupling effects into account

Temperature-induced valence transition in EuNi2(Si0.20Ge0.80)2 studied by hard X-ray photoemission spectroscopy

International Nuclear Information System (INIS)

Yamamoto, Kazuya; Kamakura, Nozomu; Taguchi, Munetaka; Chainani, Ashish; Takata, Yasutaka; Horiba, Koji; Shin, Shik; Ikenaga, Eiji; Mimura, Kojiro; Shiga, Masayuki; Wada, Hirofumi; Namatame, Hirofumi; Taniguchi, Masaki; Awaji, Mitsuhiro; Takeuchi, Akihisa; Nishino, Yoshinori; Miwa, Daigo; Tamasaku, Kenji; Ishikawa, Tetsuya; Kobayashi, Keisuke

2005-01-01

The temperature-induced mixed valence transition in EuNi 2 (Si 0.20 Ge 0.80 ) 2 has been investigated by hard X-ray (5940 eV) photoemission spectroscopy (HX-PES) for fractured surfaces, with a probing depth larger than 5 nm. The Eu 3d core-level states are studied below and above the critical valence transition temperature, T v = 80 K. The HX-PES spectra at 40 and 120 K show the mixed valence transition, with clear changes in the divalent and trivalent Eu 3d chemically shifted features. The Eu 3d HX-PES spectra indicate a mean valence of 2.70 ± 0.03 at 40 K which changes to 2.40 ± 0.03 at 120 K, in good accordance with the results of bulk Eu III -edge X-ray absorption spectroscopy measurements

Pressure induced insulator–metal transition and giant negative piezoresistance in Pr{sub 0.6}Ca{sub 0.4}Mn{sub 0.96}Al{sub 0.04}O{sub 3} polycrystal

Energy Technology Data Exchange (ETDEWEB)

Arumugam, S., E-mail: sarumugam1963@yahoo.com [Centre for High Pressure Research, School of Physics, Bharathidasan University, Tiruchirapalli 620024, Tamil Nadu (India); Thiyagarajan, R. [Center for High Pressure Science and Technology Advanced Research (HPSTAR), Shanghai 201203 (China); Kalaiselvan, G.; Sivaprakash, P. [Centre for High Pressure Research, School of Physics, Bharathidasan University, Tiruchirapalli 620024, Tamil Nadu (India)

2016-11-01

The effect of external hydrostatic pressure (P) on the magnetization (M) and resistivity (ρ) properties of charge-orbital (CO) ordered-insulating phase-separated manganite Pr{sub 0.6}Ca{sub 0.4}Mn{sub 0.96}Al{sub 0.04}O{sub 3} system is reported here. At ambient P, CO ordering transition and spin-canting in the AFM are observed at 223 K and 55 K respectively in M(T) and ρ(T) measurements. Application of P increases simultaneously the magnitude of magnetization (M) and transition temperature, and weakens the CO ordering in M(T) measurements up to 0.98 GPa. During ρ(T) measurements, P induces an insulator–metallic transition (T{sub IM}) at 1.02 GPa, and further increase of P up to 2.84 GPa leads to increase of T{sub IM} (dT{sub IM}/dP =21.6 K/GPa). ρ at T{sub IM} is reduced about three orders of magnitude at 2.84 GPa, and leads to the giant negative piezoresistance (~98%). These results are analyzed separately in two temperature regions i.e., below and above T{sub IM} by power function equation and small polaronic hopping model respectively. It is understood from these analyses that the application of P suppresses the Jahn–Teller distortions, electron–electron and electron–magnon scattering factors, and induces the insulator–metal transition in Pr{sub 0.6}Ca{sub 0.4}Mn{sub 0.96}Al{sub 0.04}O{sub 3} system. - Highlights: • Application of P on Pr{sub 0.6}Ca{sub 0.4}Mn{sub 0.96}Al{sub 0.04}O{sub 3} reduces resistivity (ρ) remarkably at low-temperatures, and exhibits an insulator to metallic transition at 1.02 GPa. • The reduction in ρ by P is about three orders of magnitude at 2.84 GPa, leads to the giant negative piezoresistance about 98%. • The effect of the suppression of Jahn–Teller distortions, electron–electron and electron–magnon scattering under an applied P exhibits to the metal-Insulator transition. • The phase-separation in this system has been tuned by both internal and external perturbations.

Phase transitions in Fe_0_._5Co_0_._5 (110) thin films

International Nuclear Information System (INIS)

Ramírez-Dámaso, G.; Castillo-Alvarado, F.L.; Rojas-Hernández, E.

2016-01-01

In this paper, we present calculations for two second-order phase transitions in (110) Fe_0_._5Co_0_._5 thin films with 11, 15, and 19 monoatomic layers. The lattice and magnetic transitions are based on thermodynamic equilibrium considerations of the magnetic alloy. The procedure proposed by Valenta and Sukiennicki was applied to calculate the composition x(i), the lattice order parameter t(i), and the magnetic order parameter σ(i) as a function of temperature T. We confirmed that both phase transitions, lattice and magnetic, are of the second order, in accordance with experimental results in the literature. The obtained behavior of these parameters indicates their inhomogeneity due to the boundary conditions on the surfaces of the thin film.

Electric response of Pb0.99[(Zr0.90Sn0.10)0.968Ti0.032]0.98Nb0.02O3 ceramics to the shock-wave-induced ferroelectric-to-antiferroelectric phase transition

International Nuclear Information System (INIS)

Jiang Dongdong; Zhang Na; Feng Yujun; Du Jinmei; Gu Yan

2012-01-01

Highlights: ► Shock wave induces the FE-to-AFE phase transition in PbNb(Zr,Sn,Ti)O 3 . ► Depoling current due to phase transition depends on shock pressure and load resistance. ► Shock pressure promotes the phase transition in short-circuit case. ► Increasing load resistance decreases the released charge. - Abstract: Shock-wave-enforced ferroelectric (FE)-to-antiferroelectric (AFE) phase transition releases a large electrical polarization, having application in pulse power technology. In the present work, the depoling currents under shock wave compression were investigated in Pb 0.99 [(Zr 0.90 Sn 0.10 ) 0.968 Ti 0.032 ] 0.98 Nb 0.02 O 3 (PZST) ceramics with composition close to the FE/AFE phase boundary. Shock wave was generated by gas-gun and propagated in a direction perpendicular to the remanent polarization. It was found that the shock pressure promoted the phase transition under the short-circuit condition. The shock pressure dependence of the released charge was associated with the evolution of FE-to-AFE phase transition. The onset of phase transition was about 0.40 GPa and complete transformation occurred at 1.23 GPa. However, the released charge decreased with increasing load resistance. The reason may be that the electric field suppresses the phase transition in uncompressed zone and/or shock induces conductivity in compressed zone. Results lay the foundation for application of PZST ceramics in shock-activated power supply.

E2 transition probabilities between Nilsson states in odd-A nuclei

International Nuclear Information System (INIS)

Krpic, D.K.; Savic, I.M.; Anicin, I.V.

1976-01-01

Presented here are the matrices needed for the calculation of E2 transition probabilities between all pairs of Nilsson states with ΔN = 0 and ΔK = 0, 1, 2. The needed coefficients of states are tabulated by Nilsson and by Davidson

Heterojunction laser operation of N-free and N-doped GaAs/sub 1-y/P/sub y/ (y=0.42--0.43, lambdaapprox.6200 A, 77 degreeK) near the direct-indirect transition (yapprox.y/subc/approx. =0.46)

International Nuclear Information System (INIS)

Coleman, J.J.; Holonyak, N. Jr.; Ludowise, M.J.; Wright, P.D.; Groves, W.O.; Keune, D.L.; Craford, M.G.

1975-01-01

The successful LPE growth of In/sub 1-x/Ga/sub x/P/sub 1-z/As/sub z//GaAs/sub 1-y/P/sub y/ single heterojunctions on VPE substrates makes possible the study of stimulated emission in N-free and N-doped GaAs/sub 1-y/P/sub y/ in a region (y=0.42--0.43) much closer to the direct-indirect transition (yequivalenty/subc/=0.46, 77 degreeK) than previously. Laser operation in N-free GaAs/sub 1-y/P/sub y/ on the GAMMA-Zn (E/sub Gamma/-E)) recombination transition has been achieved at energies as high as 2.00 eV (lambda=6200 A), and some line narrowing has been observed at energies as high as 2.01 eV (lambda=6170 A, y=0.43). In contrast to diodes made on lower composition substrates, the diodes of this work do not change their threshold current densities in the range 77--4.2 degreeK, indicating that laser operation occurs on direct transitions lying within approx.kT of the indirect donor states (Te) associated with the X conduction-band minima. From E/sub Gamma/+kTapprox.E/subX/-E/subd/ (y=0.42- []0.43), the depth of indirect Te donor states in GaAs/sub 1-y/P/sub y/ is estimated to fall in the range E/subd/=22--32 meV. Nitrogen doping in these laser diodes increases the threshold current densities since the N impurity is an efficient trap and introduces competing indirect recombination. For y=0.42--0.43 GaAs/sub 1-y/P/sub y/, heterojunction laser operation on the N trap lies approx.10 meV lower in energy than on the GAMMA-Zn transition. Beyond y=0.42--0.43, the N trap may be required for stimulated emission, but in this range diode operation at high currents becomes difficult because of the large change in carrier mobility

Analysis of the J /ψ →π0γ* transition form factor

Science.gov (United States)

Kubis, Bastian; Niecknig, Franz

2015-02-01

In view of the first measurement of the branching fraction for J /ψ →π0e+e- by the BESIII collaboration, we analyze what can be learned on the corresponding transition form factor using dispersion theory. We show that light-quark degrees of freedom dominate the spectral function, in particular two-pion intermediate states. Estimating the effects of multipion states as well as charmonium, we arrive at a prediction for the complete form factor that should be scrutinized experimentally in the future.

Squid measurement of the Verwey transition on epitaxial (1 0 0) magnetite thin films

International Nuclear Information System (INIS)

Dediu, V.; Arisi, E.; Bergenti, I.; Riminucci, A.; Solzi, M.; Pernechele, C.; Natali, M.

2007-01-01

We report results on epitaxial magnetite (Fe 3 O 4 ) thin films grown by electron beam ablation on (1 0 0) MgAl 2 O 4 substrates. At 120 K magnetite undergoes a structural and electronic transition, the so-called Verwey transition, at which magnetic and conducting properties of the material change. We observed the Verwey transition on epitaxial films with a thickness of 50 nm by comparing zero-field cooling (ZFC) and field cooling (FC) curves measured with a superconducting quantum interference device (SQUID) magnetometer. Observation of the Verwey transition by SQUID measurements in the films is sign of their high crystalline quality. Room temperature ferromagnetism has also been found by magneto-optical Kerr rotation (MOKE) and confirmed by SQUID measurements, with a hysteresis loop showing a coercive field of hundreds of Oe

Optical conductivity of Ni1 − xPtx alloys (00.25 from 0.76 to 6.6 eV

Directory of Open Access Journals (Sweden)

Lina S. Abdallah

2014-01-01

Full Text Available Using spectroscopic ellipsometry and Drude-Lorentz oscillator fitting, we determined the dielectric function and optical conductivity versus photon energy from 0.76 to 6.6 eV of 10 nm thick Ni1 − xPtx alloy (00.25 films deposited on thick thermal oxides. We find absorption peaks near 1.6 and 5.0 eV due to interband optical transitions. There is a significant broadening of the UV peak with increasing Pt content, since the bandwidth of the 3d electrons in Ni is smaller than that of the 5d bands in Pt. Our experimental observation is consistent with ab initio calculations of the density of states for Ni, Pt, and the Ni3Pt compound. Annealing the metals at 500°C for 30 s increases the optical conductivity.

A transition radiation detector which features accurate tracking and dE/dx particle identification

International Nuclear Information System (INIS)

O'Brien, E.; Lissauer, D.; McCorkle, S.; Polychronakos, V.; Takai, H.; Chi, C.Y.; Nagamiya, S.; Sippach, W.; Toy, M.; Wang, D.; Wang, Y.F.; Wiggins, C.; Willis, W.; Cherniatin, V.; Dolgoshein, B.; Bennett, M.; Chikanian, A.; Kumar, S.; Mitchell, J.T.; Pope, K.

1991-01-01

We describe the results of a test run involving a Transition Radiation Detector that can both distinguish electrons from pions with momenta greater than 0.7 GeV/c and simultaneously track particles passing through the detector. The particle identification is accomplished through a combination of the detection of Transition Radiation from the electron and the differences in electron and pion energy loss (dE/dx) in the detector. The dE/dx particle separation is most efficient below 2 GeV/c while particle ID utilizing Transition Radiation is effective above 1.5 GeV/c. Combined, the electron-pion separation is better than 5 x l0 2 . The single-wire, track-position resolution for the TRD is ∼230μm

Spontaneous transition rates for electric dipole (E1), magnetic dipole (M1), electric quadrupole (E2) and magnetic quadrupole (M2) transitions for He-like calcium and sulfur ions

International Nuclear Information System (INIS)

Kingston, A.E.; Norrington, P.H.; Boone, A.W.

2002-01-01

The spontaneous decay rates for the electric dipole (E1), electric quadrupole (E2), magnetic dipole (M1) and magnetic quadrupole (M2) transitions between all of the 1s 2 , 1s2 l and 1s3 l states have been obtained for helium-like calcium and sulfur ions. To assess the accuracy of the calculations, the transition probabilities were calculated using two sets of configuration interaction wavefunctions. One set of wavefunctions was generated using the fully relativistic GRASP code and the other was obtained using CIV3, in which relativistic effects are introduced using the Breit-Pauli approximation. The transition rates, A values, oscillator strengths and line strengths from our two calculations are found to be similar and to compare very well with other recent results for Δn=1 or 2 transitions. For Δn=0 transitions the agreement is much less good; this is mainly due to differences in the calculated excitation energies. (author)

Theoretical formulation of optical conductivity of La0.7Ca0.3MnO3 exhibiting paramagnetic insulator - ferromagnetic metal transition

Science.gov (United States)

Satiawati, L.; Majidi, M. A.

2017-07-01

A theory of high-energy optical conductivity of La0.7Ca0.3MnO3 has been proposed previously. The proposed theory works to explain the temperature-dependence of the optical conductivity for the photon energy region above ˜0.5 eV for up to ˜22 eV, but fails to capture the correct physics close to the dc limit in which metal-insulator transition occurs. The missing physics at the low energy has been acknowledged as mainly due to not incorporating phonon degree of freedom and electron-phonon interactions. In this study, we aim to complete the above theory by proposing a more complete Hamiltonian incorporating additional terms such as crystal field, two modes of Jahn-Teller vibrations, and coupling between electrons and the two Jahn-Teller vibrational modes. We solve the model by means of dynamical mean-field theory. At this stage, we aim to derive the analytical formulae involved in the calculation, and formulate the algorithmic implementation for the self-consistent calculation process. Our final goal is to compute the density of states and the optical conductivity for the complete photon energy range from 0 to 22 eV at various temperatures, and compare them with the experimental data. We expect that the improved model preserves the correct temperature-dependent physics at high photon energies, as already captured by the previous model, while it would also reveal ferromagnetic metal - paramagnetic insulator transition at the dc limit.

Phase transitions in Fe{sub 0.5}Co{sub 0.5} (110) thin films

Energy Technology Data Exchange (ETDEWEB)

Ramírez-Dámaso, G., E-mail: gramirezd@ipn.mx [Escuela Superior de Ingeniería y Arquitectura “Unidad Ticomán” del Instituto Politécnico Nacional, Av. Ticomán No. 600, Col. San José Ticomán, Del. G. A. M., C. P. 07330 Ciudad de México (Mexico); Castillo-Alvarado, F.L. [Escuela Superior de Física y Matemáticas del Instituto Politécnico Nacional, Edificio 9, Col. San Pedro Zacatenco, C. P. 07738 Ciudad de México (Mexico); Rojas-Hernández, E. [Escuela Superior de Ingeniería y Arquitectura “Unidad Ticomán” del Instituto Politécnico Nacional, Av. Ticomán No. 600, Col. San José Ticomán, Del. G. A. M., C. P. 07330 Ciudad de México (Mexico)

2016-12-15

In this paper, we present calculations for two second-order phase transitions in (110) Fe{sub 0.5}Co{sub 0.5} thin films with 11, 15, and 19 monoatomic layers. The lattice and magnetic transitions are based on thermodynamic equilibrium considerations of the magnetic alloy. The procedure proposed by Valenta and Sukiennicki was applied to calculate the composition x(i), the lattice order parameter t(i), and the magnetic order parameter σ(i) as a function of temperature T. We confirmed that both phase transitions, lattice and magnetic, are of the second order, in accordance with experimental results in the literature. The obtained behavior of these parameters indicates their inhomogeneity due to the boundary conditions on the surfaces of the thin film.

Dependence of the interband transitions on the in mole fraction and the applied electric field in In xGa1-xAs/In0.52Al0.48As multiple quantum wells

International Nuclear Information System (INIS)

Kim, J.H.; Woo, J.T.; Lee, I.; Kim, T.W.; Yoo, K.H.; Kim, M.D.; Ram-Mohan, L.R.

2005-01-01

Transmission electron microscopy (TEM) and photocurrent (PC) measurements were carried out to investigate the microstructural properties and excitonic transitions in In x Ga 1-x As/In 0.52 Al 0.48 As multiple quantum wells (MQWs) for x = 0.54, 0.57 and 0.60. TEM images showed that high-quality 11-period In x Ga 1-x As/In 0.52 Al 0.48 As MQWs had high-quality heterointerfaces. The results for the PC spectra at 300 K showed that the peaks corresponding to the excitonic transitions from the ground state electronic sub-band to the ground state heavy-hole band (E 1 -HH 1 ) and the ground state electronic sub-band to the ground state light-hole band (E 1 -LH 1 ) became closer to each other with decreasing In mole fraction and that E 1 -HH 1 and E 1 -LH 1 excitonic peaks shifted to longer wavelength with increasing applied electric field. The calculated values of the E 1 -HH 1 interband transition energies were in qualitative agreement with those obtained form the PC measurements with and without applied electric field. These results can be helpful in understanding potential applications of In x Ga 1-x As/In y Al 1-y As MQWs dependent on In mole fraction and applied electric field in long-wavelength optoelectronic devices

Absolute M1 and E2 Transition Probabilities in 2{sup 33}U

Energy Technology Data Exchange (ETDEWEB)

Malmskog, S G; Hoejeberg, M

1967-08-15

Using the delayed coincidence technique, the following half lives have been determined for different excited states in {sup 233}U: T{sub 1/2} (311.9 keV level) = (1.20 {+-} 0.15) x 10{sup -10} sec, T{sub 1/2} (340.5 keV level) = (5.2 {+-} 1.0) x 10{sup -11} sec, T{sub 1/2} (398.6 keV level) = (5.5 {+-} 2.0) x 10{sup -11} sec and T{sub 1/2} (415.8 keV level) < 3 x 10{sup -11}sec. From these half life determinations, together with earlier known electron intensities and conversion coefficients, 22 reduced B(Ml) and B(E2) transition probabilities (including 9 limits) have been deduced. The rotational transitions give information on the parameters {delta} and (g{sub K} - g{sub R}) . The experimental M1 and E2 transition rates between members of different bands have been analysed in terms of the predictions of the Nilsson model, taking also pairing correlations and Coriolis coupling effects into account.

Effects of oxygen content and heating rate on phase transition behavior in Bi2(V0.95Ti0.05)O5.475-x

International Nuclear Information System (INIS)

Taninouchi, Yu-ki; Uda, Tetsuya; Ichitsubo, Tetsu; Awakura, Yasuhiro; Matsubara, Eiichiro

2011-01-01

Highlights: → Phase transition behavior of oxide-ion conductor Bi 2 (V 0.95 Ti 0.05 )O 5.475-x , which has various thermal histories and physical forms. → At the same heating rate of 10 K min -1 , Bi 2 (V 0.95 Ti 0.05 )O 5.475-x with less oxygen content exhibits transition from α f to β f at a higher temperature and the transition from β f to γ f at a lower temperature. → α f directly transformed to β f at fast heating rates. At a slower heating rate of 2 K min -1 , β f precipitated from α f due to the sufficient diffusion of Ti and oxygen vacancies. - Abstract: The phase transition behavior of oxide-ion conductor Bi 2 (V 0.95 Ti 0.05 )O 5.475-x , which has various thermal histories and sample forms, has been studied by means of differential scanning calorimetry. Thermogravimetric analysis revealed that the oxygen content per compositional formula varied with the applied thermal treatment, although no significant structural difference was observed by X-ray diffraction (XRD) analysis. The phase transition behavior from α f to β f and from β f to γ f , observed at a heating rate of 10 K min -1 , are markedly affected by the sample preparation. For example, the endothermic peak of the transition from α f to β f appeared at around 400 deg. C for quenched powder and at around 320 deg. C for powder cooled at 0.5 K min -1 . The trend of the transition temperatures can be qualitatively explained in terms of oxygen content, i.e., Bi 2 (V 0.95 Ti 0.05 )O 5.475-x with less oxygen content exhibits the transition from α f to β f at a higher temperature and the transition from β f to γ f at a lower temperature. We confirmed the two types of transition behavior from α f to β f depending on heating rate of DSC and high-temperature X-ray diffraction (HT-XRD) analysis. At rapid heating rates of 10 and 40 K min -1 , α f transformed to β f directly. Meanwhile, at a slow heating rate of 2 K min -1 , the β f precipitated from α f because slow heating

Search for the Decay Modes D0 to e+ e-, D0 to mu+ mu-, and D0 to e+/- mu+/-

Energy Technology Data Exchange (ETDEWEB)

Lees, J. P.

2012-08-03

We present searches for the rare decay modes D{sup 0} {yields} e{sup +}e{sup -}, D{sup 0} {yields} {mu}{sup +}{mu}{sup -}, and D{sup 0} {yields} e{sup {+-}}{mu}{sup {-+}} in continuum e{sup +}e{sup -} {yields} c{bar c} events recorded by the BABAR detector in a data sample that corresponds to an integrated luminosity of 468 fb{sup -1}. These decays are highly GIM suppressed but may be enhanced in several extensions of the Standard Model. Our observed event yields are consistent with the expected backgrounds. An excess is seen in the D{sup 0} {yields} {mu}{sup +}{mu}{sup -} channel, although the observed yield is consistent with an upward background fluctuation at the 5% level. Using the Feldman-Cousins method, we set the following 90% confidence level intervals on the branching fractions: {Beta}(D{sup 0} {yields} e{sup +}e{sup -}) < 1.7 x 10{sup -7}, {Beta}(D{sup 0} {yields} {mu}{sup +}{mu}{sup -}) within [0.6, 8.1] x 10{sup -7}, and {Beta}(D{sup 0} {yields} e{sup {+-}}{mu}{sup {-+}}) < 3.3 x 10{sup -7}.

Martensitic phase transitions in Co-0.85 at % Fe

International Nuclear Information System (INIS)

Prem, M.

1997-12-01

Co-0.85at%Fe shows the two martensitic phase transitions hcp-dhcp and dhcp-fcc. The lattice dynamics of Co-0.85at%Fe was investigated by the means of inelastic neutron scattering at a series of temperatures up to 750K in order to understand the two martensitic phase transitions of this system. In all of the measured phonon branches anomalies were neither found near the hcp-dhcp phase transition nor going through the dhcp-fcc transition. Lattice-parameter scans were performed through the whole temperature range. Diffuse neutron scattering revealed a lattice parameter shift between the dhcp and fcc phase of ∼0.4 % measured at the same temperature. This was possible because the system shows a wide temperature hysteresis at the two phase transitions. In the temperature region of coexistence of dhcp and fcc phase diffuse satellites arose near the (111)fcc Bragg peak (which is equivalent to the (00.2)dhcp peak). Their intensity varied in accordance to the volume fraction of the phases but vanished on changing wavelength. The elastic measurements were performed at the Austrian triple axis spectrometer VALSE located at the Laboratoire Leon Brillouin (LLB) in Saclay (F); the inelastic measurements were performed at the spectrometers IN3 and INS of the Institute Laue Langevin (ILL) in Grenoble (F). (author)

The stability boundary of group-III transition metal diboride ScB 2 (0 0 0 1) surfaces

Science.gov (United States)

Zhao, Hui; Qin, Na

2012-01-01

Experimental observations and theoretical investigations exhibit that a group-IV(V) transition metal diboride (0 0 0 1) surface is terminated with a 1 × 1 TM(B) layer. As to a group-III transition metal diboride, we have investigated the stability boundary of ScB2 (0 0 0 1) surfaces using first principles total energy plane-wave pseudopotential method based on density functional theory. The Mulliken charge population analysis shows that Sc atoms in the second layer cannot provide B atoms in the first layer with sufficient electrons to form a complete graphene-like boron layer. We also found that the charge transfer between the first and the second layer for the B-terminated surface is more than that for Sc-terminated surface. It elucidates the reason that the outermost interlayer spacing contract more strongly in the B-terminated surface than in the Sc-terminated surface. The surface energies of both terminated ScB2 (0 0 0 1) surfaces as a function of the chemical potential of B are also calculated to check the relative stability of the two surface structures.

High temperature spin-glass-like transition in La0.67Sr0.33MnO3 nanofibers near the Curie point.

Science.gov (United States)

Lu, Ruie; Yang, Sen; Li, Yitong; Chen, Kaiyun; Jiang, Yun; Fu, Bi; Zhang, Yin; Zhou, Chao; Xu, Minwei; Zhou, Xuan

2017-06-28

The glassy transition of superparamagnetic (SPM) (r glass-like (SGL) behavior near the Curie point (T C ), i.e., T 0 = 330 K, in La 0.67 Sr 0.33 MnO 3 (LSMO) nanofibers (NFs) composed of nanoparticles beyond the SPM size (r ≫ r 0 ), resulting in a significant increase of the glass transition temperature. This SGL transition near the T C of bulk LSMO can be explained to be the scenario of locally ordered clusters embedded in a disordered host, in which the assembly of nanoparticles has a magnetic core-shell model driven by surface spin glass. The presence of a surface spin glass of nanoparticles was proved by the Almeida-Thouless line δT f ∝ H 2/3 , exchange bias, and reduced saturation magnetization of the NF system. Composite dynamics were found - that is, both the SPM and the super-spin-glass (SSG) behavior are found in such an NF system. The bifurcation of the zero-field-cooled (ZFC) and field-cooled (FC) magnetization vs. temperature curves at the ZFC peak, and the flatness of FC magnetization involve SSG, while the frequency-dependent ac susceptibility anomaly follows the Vogel-Fulcher law that implies weak dipole interactions of the SPM model. This finding can help us to find a way to search for high temperature spin glass materials.

Phase transitions and optical characterization of lead-free piezoelectric (K0.5Na0.5)0.96Li0.04(Nb 0.8Ta0.2)O3 thin films

KAUST Repository

Yao, Yingbang

2013-06-01

Lead-free piezoelectric thin films, (K0.5Na0.5) 0.96Li0.04(Nb0.8Ta0.2)O 3, were epitaxially grown on MgO(001) and Nb-doped SrTiO 3(001) substrates using pulsed laser deposition. The optimum deposition temperature was found to be 600 C. Two types of in-plane orientations were observed in the films depending on the substrates used. The transmittance and photoluminescence spectra as well as the dielectric and ferroelectric properties of the films were measured. The measured band-gap energy was found to be decreased with the deposition temperature. The dielectric constant decreased from 550 to 300 as the frequency increased from 100 Hz to 1 MHz. The measured remnant polarization and coercive field were 4 μC/cm2 and 68 kV/cm, respectively. The phase transitions of the films were studied by Raman spectroscopy. Two distinct anomalies originating from the cubic-to-tetragonal (TC-T ~ 300 C) and tetragonal-to-orthorhombic (TT-O ~ 120 C) phase transitions were observed. Our results show that Raman spectroscopy is a powerful tool in identifying the phase transitions in ferroelectric thin films. © 2013 Elsevier B.V.

Phase transition in the (Li 0.5-( x/2) K 0.5-( x/2) Cs x) 2SO 4 system

Science.gov (United States)

Hamed, A. E.; El-Aziz, Y. M. Abd.; Madi, N. K.; Kassem, M. E.

1995-12-01

Phase transition in the (Li 0.5-( x/2) K 0.5-( x/2) Cs x) 2SO 4 system was studied by measuring the specific heat at constant pressure, C p, as a function of temperature in the temperature range 300-800 K. For non-zero values of X ( X = 0.2%, 0.5%, 1% and 2%) the critical behaviour of the phase transition was found to change considerably compared with that of X = 0 or pure LiKSO 4. The observed change in the phase transition with increase of Cs 2SO 4 content ( X) was accompanied by a decrease in the thermodynamic parameters: the value of the specific heat at the transition point (Δ C P) max, the transition temperature, T1, and the value of the energy of ordering. The results were interpreted within the Landau thermodynamic theory of the phase transition.

Search for the decays B_{(s)};{0} --> e;{+} micro;{-} and B_{(s)};{0} --> e;{+} e;{-} in CDF run II.

Science.gov (United States)

Aaltonen, T; Adelman, J; Akimoto, T; Alvarez González, B; Amerio, S; Amidei, D; Anastassov, A; Annovi, A; Antos, J; Apollinari, G; Apresyan, A; Arisawa, T; Artikov, A; Ashmanskas, W; Attal, A; Aurisano, A; Azfar, F; Azzurri, P; Badgett, W; Barbaro-Galtieri, A; Barnes, V E; Barnett, B A; Bartsch, V; Bauer, G; Beauchemin, P-H; Bedeschi, F; Beecher, D; Behari, S; Bellettini, G; Bellinger, J; Benjamin, D; Beretvas, A; Beringer, J; Bhatti, A; Binkley, M; Bisello, D; Bizjak, I; Blair, R E; Blocker, C; Blumenfeld, B; Bocci, A; Bodek, A; Boisvert, V; Bolla, G; Bortoletto, D; Boudreau, J; Boveia, A; Brau, B; Bridgeman, A; Brigliadori, L; Bromberg, C; Brubaker, E; Budagov, J; Budd, H S; Budd, S; Burke, S; Burkett, K; Busetto, G; Bussey, P; Buzatu, A; Byrum, K L; Cabrera, S; Calancha, C; Campanelli, M; Campbell, M; Canelli, F; Canepa, A; Carls, B; Carlsmith, D; Carosi, R; Carrillo, S; Carron, S; Casal, B; Casarsa, M; Castro, A; Catastini, P; Cauz, D; Cavaliere, V; Cavalli-Sforza, M; Cerri, A; Cerrito, L; Chang, S H; Chen, Y C; Chertok, M; Chiarelli, G; Chlachidze, G; Chlebana, F; Cho, K; Chokheli, D; Chou, J P; Choudalakis, G; Chuang, S H; Chung, K; Chung, W H; Chung, Y S; Chwalek, T; Ciobanu, C I; Ciocci, M A; Clark, A; Clark, D; Compostella, G; Convery, M E; Conway, J; Cordelli, M; Cortiana, G; Cox, C A; Cox, D J; Crescioli, F; Cuenca Almenar, C; Cuevas, J; Culbertson, R; Cully, J C; Dagenhart, D; Datta, M; Davies, T; de Barbaro, P; De Cecco, S; Deisher, A; De Lorenzo, G; Dell'orso, M; Deluca, C; Demortier, L; Deng, J; Deninno, M; Derwent, P F; di Giovanni, G P; Dionisi, C; Di Ruzza, B; Dittmann, J R; D'Onofrio, M; Donati, S; Dong, P; Donini, J; Dorigo, T; Dube, S; Efron, J; Elagin, A; Erbacher, R; Errede, D; Errede, S; Eusebi, R; Fang, H C; Farrington, S; Fedorko, W T; Feild, R G; Feindt, M; Fernandez, J P; Ferrazza, C; Field, R; Flanagan, G; Forrest, R; Frank, M J; Franklin, M; Freeman, J C; Furic, I; Gallinaro, M; Galyardt, J; Garberson, F; Garcia, J E; Garfinkel, A F; Genser, K; Gerberich, H; Gerdes, D; Gessler, A; Giagu, S; Giakoumopoulou, V; Giannetti, P; Gibson, K; Gimmell, J L; Ginsburg, C M; Giokaris, N; Giordani, M; Giromini, P; Giunta, M; Giurgiu, G; Glagolev, V; Glenzinski, D; Gold, M; Goldschmidt, N; Golossanov, A; Gomez, G; Gomez-Ceballos, G; Goncharov, M; González, O; Gorelov, I; Goshaw, A T; Goulianos, K; Gresele, A; Grinstein, S; Grosso-Pilcher, C; Grundler, U; Guimaraes da Costa, J; Gunay-Unalan, Z; Haber, C; Hahn, K; Hahn, S R; Halkiadakis, E; Han, B-Y; Han, J Y; Happacher, F; Hara, K; Hare, D; Hare, M; Harper, S; Harr, R F; Harris, R M; Hartz, M; Hatakeyama, K; Hays, C; Heck, M; Heijboer, A; Heinrich, J; Henderson, C; Herndon, M; Heuser, J; Hewamanage, S; Hidas, D; Hill, C S; Hirschbuehl, D; Hocker, A; Hou, S; Houlden, M; Hsu, S-C; Huffman, B T; Hughes, R E; Husemann, U; Hussein, M; Huston, J; Incandela, J; Introzzi, G; Iori, M; Ivanov, A; James, E; Jang, D; Jayatilaka, B; Jeon, E J; Jha, M K; Jindariani, S; Johnson, W; Jones, M; Joo, K K; Jun, S Y; Jung, J E; Junk, T R; Kamon, T; Kar, D; Karchin, P E; Kato, Y; Kephart, R; Keung, J; Khotilovich, V; Kilminster, B; Kim, D H; Kim, H S; Kim, H W; Kim, J E; Kim, M J; Kim, S B; Kim, S H; Kim, Y K; Kimura, N; Kirsch, L; Klimenko, S; Knuteson, B; Ko, B R; Kondo, K; Kong, D J; Konigsberg, J; Korytov, A; Kotwal, A V; Kreps, M; Kroll, J; Krop, D; Krumnack, N; Kruse, M; Krutelyov, V; Kubo, T; Kuhr, T; Kulkarni, N P; Kurata, M; Kwang, S; Laasanen, A T; Lami, S; Lammel, S; Lancaster, M; Lander, R L; Lannon, K; Lath, A; Latino, G; Lazzizzera, I; Lecompte, T; Lee, E; Lee, H S; Lee, S W; Leone, S; Lewis, J D; Lin, C-S; Linacre, J; Lindgren, M; Lipeles, E; Lister, A; Litvintsev, D O; Liu, C; Liu, T; Lockyer, N S; Loginov, A; Loreti, M; Lovas, L; Lucchesi, D; Luci, C; Lueck, J; Lujan, P; Lukens, P; Lungu, G; Lyons, L; Lys, J; Lysak, R; Macqueen, D; Madrak, R; Maeshima, K; Makhoul, K; Maki, T; Maksimovic, P; Malde, S; Malik, S; Manca, G; Manousakis-Katsikakis, A; Margaroli, F; Marino, C; Marino, C P; Martin, A; Martin, V; Martínez, M; Martínez-Ballarín, R; Maruyama, T; Mastrandrea, P; Masubuchi, T; Mathis, M; Mattson, M E; Mazzanti, P; McFarland, K S; McIntyre, P; McNulty, R; Mehta, A; Mehtala, P; Menzione, A; Merkel, P; Mesropian, C; Miao, T; Miladinovic, N; Miller, R; Mills, C; Milnik, M; Mitra, A; Mitselmakher, G; Miyake, H; Moggi, N; Moon, C S; Moore, R; Morello, M J; Morlock, J; Movilla Fernandez, P; Mülmenstädt, J; Mukherjee, A; Muller, Th; Mumford, R; Murat, P; Mussini, M; Nachtman, J; Nagai, Y; Nagano, A; Naganoma, J; Nakamura, K; Nakano, I; Napier, A; Necula, V; Nett, J; Neu, C; Neubauer, M S; Neubauer, S; Nielsen, J; Nodulman, L; Norman, M; Norniella, O; Nurse, E; Oakes, L; Oh, S H; Oh, Y D; Oksuzian, I; Okusawa, T; Orava, R; Osterberg, K; Griso, S Pagan; Palencia, E; Papadimitriou, V; Papaikonomou, A; Paramonov, A A; Parks, B; Pashapour, S; Patrick, J; Pauletta, G; Paulini, M; Paus, C; Peiffer, T; Pellett, D E; Penzo, A; Phillips, T J; Piacentino, G; Pianori, E; Pinera, L; Pitts, K; Plager, C; Pondrom, L; Poukhov, O; Pounder, N; Prakoshyn, F; Pronko, A; Proudfoot, J; Ptohos, F; Pueschel, E; Punzi, G; Pursley, J; Rademacker, J; Rahaman, A; Ramakrishnan, V; Ranjan, N; Redondo, I; Renton, P; Renz, M; Rescigno, M; Richter, S; Rimondi, F; Ristori, L; Robson, A; Rodrigo, T; Rodriguez, T; Rogers, E; Rolli, S; Roser, R; Rossi, M; Rossin, R; Roy, P; Ruiz, A; Russ, J; Rusu, V; Rutherford, B; Saarikko, H; Safonov, A; Sakumoto, W K; Saltó, O; Santi, L; Sarkar, S; Sartori, L; Sato, K; Savoy-Navarro, A; Schlabach, P; Schmidt, A; Schmidt, E E; Schmidt, M A; Schmidt, M P; Schmitt, M; Schwarz, T; Scodellaro, L; Scribano, A; Scuri, F; Sedov, A; Seidel, S; Seiya, Y; Semenov, A; Sexton-Kennedy, L; Sforza, F; Sfyrla, A; Shalhout, S Z; Shears, T; Shepard, P F; Shimojima, M; Shiraishi, S; Shochet, M; Shon, Y; Shreyber, I; Sidoti, A; Sinervo, P; Sisakyan, A; Slaughter, A J; Slaunwhite, J; Sliwa, K; Smith, J R; Snider, F D; Snihur, R; Soha, A; Somalwar, S; Sorin, V; Spalding, J; Spreitzer, T; Squillacioti, P; Stanitzki, M; St Denis, R; Stelzer, B; Stelzer-Chilton, O; Stentz, D; Strologas, J; Strycker, G L; Stuart, D; Suh, J S; Sukhanov, A; Suslov, I; Suzuki, T; Taffard, A; Takashima, R; Takeuchi, Y; Tanaka, R; Tecchio, M; Teng, P K; Terashi, K; Thom, J; Thompson, A S; Thompson, G A; Thomson, E; Tipton, P; Ttito-Guzmán, P; Tkaczyk, S; Toback, D; Tokar, S; Tollefson, K; Tomura, T; Tonelli, D; Torre, S; Torretta, D; Totaro, P; Tourneur, S; Trovato, M; Tsai, S-Y; Tu, Y; Turini, N; Ukegawa, F; Vallecorsa, S; van Remortel, N; Varganov, A; Vataga, E; Vázquez, F; Velev, G; Vellidis, C; Vidal, M; Vidal, R; Vila, I; Vilar, R; Vine, T; Vogel, M; Volobouev, I; Volpi, G; Wagner, P; Wagner, R G; Wagner, R L; Wagner, W; Wagner-Kuhr, J; Wakisaka, T; Wallny, R; Wang, S M; Warburton, A; Waters, D; Weinberger, M; Weinelt, J; Wenzel, H; Wester, W C; Whitehouse, B; Whiteson, D; Wicklund, A B; Wicklund, E; Wilbur, S; Williams, G; Williams, H H; Wilson, P; Winer, B L; Wittich, P; Wolbers, S; Wolfe, C; Wright, T; Wu, X; Würthwein, F; Xie, S; Yagil, A; Yamamoto, K; Yamaoka, J; Yang, U K; Yang, Y C; Yao, W M; Yeh, G P; Yoh, J; Yorita, K; Yoshida, T; Yu, G B; Yu, I; Yu, S S; Yun, J C; Zanello, L; Zanetti, A; Zhang, X; Zheng, Y; Zucchelli, S

2009-05-22

We report results from a search for the lepton flavor violating decays B_{s};{0} --> e;{+} micro;{-} and B;{0} --> e;{+} micro;{-}, and the flavor-changing neutral-current decays B_{s};{0} --> e;{+} e;{-} and B;{0} --> e;{+} e;{-}. The analysis uses data corresponding to 2 fb;{-1} of integrated luminosity of pp[over ] collisions at sqrt[s] = 1.96 TeV collected with the upgraded Collider Detector (CDF II) at the Fermilab Tevatron. The observed number of B0 and B_{s};{0} candidates is consistent with background expectations. The resulting Bayesian upper limits on the branching ratios at 90% credibility level are B(B_{s};{0} --> e;{+} micro;{-}) e;{+} micro;{-}) e;{+} e;{-}) e;{+} e;{-}) e;{+} micro;{-}), the following lower bounds on the Pati-Salam leptoquark masses are also derived: M_{LQ}(B_{s};{0} --> e;{+} micro;{-}) > 47.8 TeV/c;{2}, and M_{LQ}(B;{0} --> e;{+} micro;{-}) > 59.3 TeV / c;{2}, at 90% credibility level.

Identification of the additional transition around the E{sub 0} critical point in photoreflectance spectra of GaInAsSb epitaxial films

Energy Technology Data Exchange (ETDEWEB)

Tirado-Mejia, L; Prias-Barragan, J J; Gomez, J F; Ariza-Calderon, H, E-mail: litirado@uniquindio.edu.c [Laboratorio de Optoelectronica, Universidad del Quindio (Colombia)

2009-05-01

We present the analysis of the photoreflectance (PR) spectra line-shape of GaInAsSb films over GaSb. The studied samples were grown by liquid phase epitaxy technique. The growth parameters such as initial temperature and contact time were the same for all samples, but the precursor solution varied slightly in the As concentration. The cooling rate was different for each sample. The PR spectra were obtained at low temperature, modulated by a 632.8 nm He-Ne laser. These spectra were fitted using the third derivative lorentzian function but, for one of the samples exhibiting an additional structure around the E{sub 0} critical point oscillation, it was also necessary to use a first derivative lorentzian function, associated to an excitonic transition. This interpretation of the new PR feature was analyzed according to X-ray diffractograms. Comparing the FWHM of the main peak in the diffractograms it was found that the sample which exhibits the excitonic transition has the best crystalline quality, and was the sample with the lower cooling rate. The excitonic energy value obtained (9.7 meV) is in agreement with the value reported in the related literature.

A new role for E12/E47 in the repression of E-cadherin expression and epithelial-mesenchymal transitions

DEFF Research Database (Denmark)

Perez-Moreno, M A; Locascio, A; Rodrigo, I

2001-01-01

Down-regulation of E-cadherin expression is a determinant of tumor cell invasiveness, an event frequently associated with epithelial-mesenchymal transitions. Here we show that the mouse E12/E47 basic helix-loop-helix transcription factor (the E2A gene product) acts as a repressor of E-cadherin ex......Down-regulation of E-cadherin expression is a determinant of tumor cell invasiveness, an event frequently associated with epithelial-mesenchymal transitions. Here we show that the mouse E12/E47 basic helix-loop-helix transcription factor (the E2A gene product) acts as a repressor of E...

Study of the $B^0 \\rightarrow K^{\\ast 0}e^+ e^-$ decay with the LHCb detector and development of a novel concept of PID detector: the Focusing DIRC

CERN Document Server

AUTHOR|(CDS)2088184; Arnaud, Nicolas

Flavour-changing neutral current processes of the type $b \\to s\\gamma$ are forbidden at the tree level in the Standard Model (SM) and occur at leading order through radiative loop diagrams. Therefore, they are sensitive to new physics (NP), which may contribute with competing diagrams. Furthermore, the chirality of the weak interaction in the SM implies that the photon emitted has left-handed polarisation. However, a whole class of NP theories do not share this SM feature and may manifest unambiguously as a right-handed contribution to the polarisation. This thesis presents the first study of the ${b}{s\\gamma}$ photon polarisation through an angular analysis of the $B^0 \\rightarrow K^{\\ast 0}e^+ e^-$ channel. Even though $B^0 \\rightarrow K^{\\ast 0}e^+ e^-$ is not a radiative $b\\to s$ transition, the contribution from a virtual photon coupling to the lepton pair dominates in the low-$q^2$ region. Furthermore, the channel with electrons rather than muons allows to better isolate the virtual photon contribution ...

Critical end point of the first-order ferromagnetic transition in a Sm{sub 0.55}(Sr{sub 0.5}Ca{sub 0.5}){sub 0.45}MnO{sub 3} single crystal

Energy Technology Data Exchange (ETDEWEB)

Radheep, D. Mohan [Centre for High Pressure Research, School of Physics, Bharathidasan University, Tiruchirappalli 620 024 (India); Sarkar, P. [Department of Physics, Serampore College, Serampore 712 201 (India); Arumugam, S. [Centre for High Pressure Research, School of Physics, Bharathidasan University, Tiruchirappalli 620 024 (India); Suryanarayanan, R. [Laboratoire de Physico-Chimie de l' Etat Solide, ICMMO, CNRS, UMR8182, Universite Paris-Sud, 91405 Orsay (France); Mandal, P., E-mail: prabhat.mandal@saha.ac.in [Saha Institute of Nuclear Physics, 1/AF Bidhannagar, Calcutta 700 064 (India)

2014-09-01

We report on the magnetic field (H) and hydrostatic pressure (P) dependence of the order of the ferromagnetic (FM) to paramagnetic phase transition in a Sm{sub 0.55}(Sr{sub 0.5}Ca{sub 0.5}){sub 0.45}MnO{sub 3} single crystal. At ambient condition, the system exhibits a first-order FM transition at T{sub C}≈82K (in heating cycle) with strong thermal hysteresis (∼13 K). The application of external H and P increases T{sub C}, suppresses the hysteresis width, and thus weakens the first-order nature of the transition. Our analysis reveals that the hysteresis vanishes and the first-order FM transition becomes a crossover above a critical magnetic field H{sub cr}≈11.5T. The value of H{sub cr} is highest among the manganite family, although the first-order nature of the FM transition is believed to be strongest in Eu{sub 1−x}Sr{sub x}MnO{sub 3}(x≈0.45). - Highlights: • System shows a strong first-order ferromagnetic to paramagnetic phase transition. • Extremely sharp metal–insulator transition at around 82 K. • The value of critical magnetic field at which first-order transition becomes a crossover is highest among manganites. • The nature of transition is sensitive to external perturbations such as magnetic field and pressure.

Photoemission spectroscopy of the charge-ordering transition in Pr0.5Sr0.5MnO3

International Nuclear Information System (INIS)

Chainani, A.; Kumigashira, H.; Takahashi, T.; Tomioka, Y.; Kuwahara, H.; Tokura, Y.

1996-01-01

In this paper, the electronic structure of the magnetite Pr 0.5 Sr 0.5 MnO 3 across the charge ordering transition is studied using temperature-dependent photoemission spectroscopy. Ultra-violet photoemission spectroscopy have been performed as a function of temperature (25-300K) to investigate the changes in the single-particle density of states across the metal-nonmetal and the para-ferro transitions

Measurement of the $B^0 \\to K^{*0}e^+e^-$ branching fraction at low dilepton mass

CERN Document Server

INSPIRE-00258707; Abellan Beteta, C; Adametz, A; Adeva, B; Adinolfi, M; Adrover, C; Affolder, A; Ajaltouni, Z; Albrecht, J; Alessio, F; Alexander, M; Ali, S; Alkhazov, G; Alvarez Cartelle, P; Alves Jr, A A; Amato, S; Amhis, Y; Anderlini, L; Anderson, J; Andreassen, R; Appleby, R B; Aquines Gutierrez, O; Archilli, F; Artamonov, A; Artuso, M; Aslanides, E; Auriemma, G; Bachmann, S; Back, J J; Baesso, C; Balagura, V; Baldini, W; Barlow, R J; Barschel, C; Barsuk, S; Barter, W; Bauer, Th; Bay, A; Beddow, J; Bediaga, I; Belogurov, S; Belous, K; Belyaev, I; Ben-Haim, E; Benayoun, M; Bencivenni, G; Benson, S; Benton, J; Berezhnoy, A; Bernet, R; Bettler, M -O; van Beuzekom, M; Bien, A; Bifani, S; Bird, T; Bizzeti, A; Bjørnstad, P M; Blake, T; Blanc, F; Blanks, C; Blouw, J; Blusk, S; Bobrov, A; Bocci, V; Bondar, A; Bondar, N; Bonivento, W; Borghi, S; Borgia, A; Bowcock, T J V; Bowen, E; Bozzi, C; Brambach, T; van den Brand, J; Bressieux, J; Brett, D; Britsch, M; Britton, T; Brook, N H; Brown, H; Burducea, I; Bursche, A; Buytaert, J; Cadeddu, S; Callot, O; Calvi, M; Calvo Gomez, M; Camboni, A; Campana, P; Carbone, A; Carboni, G; Cardinale, R; Cardini, A; Carranza-Mejia, H; Carson, L; Carvalho Akiba, K; Casse, G; Cattaneo, M; Cauet, Ch; Charles, M; Charpentier, Ph; Chen, P; Chiapolini, N; Chrzaszcz, M; Ciba, K; Cid Vidal, X; Ciezarek, G; Clarke, P E L; Clemencic, M; Cliff, H V; Closier, J; Coca, C; Coco, V; Cogan, J; Cogneras, E; Collins, P; Comerma-Montells, A; Contu, A; Cook, A; Coombes, M; Coquereau, S; Corti, G; Couturier, B; Cowan, G A; Craik, D; Cunliffe, S; Currie, R; D'Ambrosio, C; David, P; David, P N Y; De Bonis, I; De Bruyn, K; De Capua, S; De Cian, M; De Miranda, J M; De Paula, L; De Silva, W; De Simone, P; Decamp, D; Deckenhoff, M; Degaudenzi, H; Del Buono, L; Deplano, C; Derkach, D; Deschamps, O; Dettori, F; Di Canto, A; Dickens, J; Dijkstra, H; Dogaru, M; Domingo Bonal, F; Donleavy, S; Dordei, F; Dosil Suárez, A; Dossett, D; Dovbnya, A; Dupertuis, F; Dzhelyadin, R; Dziurda, A; Dzyuba, A; Easo, S; Egede, U; Egorychev, V; Eidelman, S; van Eijk, D; Eisenhardt, S; Eitschberger, U; Ekelhof, R; Eklund, L; El Rifai, I; Elsasser, Ch; Elsby, D; Falabella, A; Färber, C; Fardell, G; Farinelli, C; Farry, S; Fave, V; Ferguson, D; Fernandez Albor, V; Ferreira Rodrigues, F; Ferro-Luzzi, M; Filippov, S; Fitzpatrick, C; Fontana, M; Fontanelli, F; Forty, R; Francisco, O; Frank, M; Frei, C; Frosini, M; Furcas, S; Furfaro, E; Gallas Torreira, A; Galli, D; Gandelman, M; Gandini, P; Gao, Y; Garofoli, J; Garosi, P; Garra Tico, J; Garrido, L; Gaspar, C; Gauld, R; Gersabeck, E; Gersabeck, M; Gershon, T; Ghez, Ph; Gibson, V; Gligorov, V V; Göbel, C; Golubkov, D; Golutvin, A; Gomes, A; Gordon, H; Grabalosa Gándara, M; Graciani Diaz, R; Granado Cardoso, L A; Graugés, E; Graziani, G; Grecu, A; Greening, E; Gregson, S; Grünberg, O; Gui, B; Gushchin, E; Guz, Yu; Gys, T; Hadjivasiliou, C; Haefeli, G; Haen, C; Haines, S C; Hall, S; Hampson, T; Hansmann-Menzemer, S; Harnew, N; Harnew, S T; Harrison, J; Harrison, P F; Hartmann, T; He, J; Heijne, V; Hennessy, K; Henrard, P; Hernando Morata, J A; van Herwijnen, E; Hicks, E; Hill, D; Hoballah, M; Hombach, C; Hopchev, P; Hulsbergen, W; Hunt, P; Huse, T; Hussain, N; Hutchcroft, D; Hynds, D; Iakovenko, V; Ilten, P; Jacobsson, R; Jaeger, A; Jans, E; Jansen, F; Jaton, P; Jing, F; John, M; Johnson, D; Jones, C R; Jost, B; Kaballo, M; Kandybei, S; Karacson, M; Karbach, T M; Kenyon, I R; Kerzel, U; Ketel, T; Keune, A; Khanji, B; Kochebina, O; Komarov, I; Koopman, R F; Koppenburg, P; Korolev, M; Kozlinskiy, A; Kravchuk, L; Kreplin, K; Kreps, M; Krocker, G; Krokovny, P; Kruse, F; Kucharczyk, M; Kudryavtsev, V; Kvaratskheliya, T; La Thi, V N; Lacarrere, D; Lafferty, G; Lai, A; Lambert, D; Lambert, R W; Lanciotti, E; Lanfranchi, G; Langenbruch, C; Latham, T; Lazzeroni, C; Le Gac, R; van Leerdam, J; Lees, J -P; Lefèvre, R; Leflat, A; Lefrançois, J; Leroy, O; Li, Y; Li Gioi, L; Liles, M; Lindner, R; Linn, C; Liu, B; Liu, G; von Loeben, J; Lopes, J H; Lopez Asamar, E; Lopez-March, N; Lu, H; Luisier, J; Luo, H; Machefert, F; Machikhiliyan, I V; Maciuc, F; Maev, O; Malde, S; Manca, G; Mancinelli, G; Mangiafave, N; Marconi, U; Märki, R; Marks, J; Martellotti, G; Martens, A; Martin, L; Martín Sánchez, A; Martinelli, M; Martinez Santos, D; Martins Tostes, D; Massafferri, A; Matev, R; Mathe, Z; Matteuzzi, C; Matveev, M; Maurice, E; Mazurov, A; McCarthy, J; McNulty, R; Meadows, B; Meier, F; Meissner, M; Merk, M; Milanes, D A; Minard, M -N; Molina Rodriguez, J; Monteil, S; Moran, D; Morawski, P; Mountain, R; Mous, I; Muheim, F; Müller, K; Muresan, R; Muryn, B; Muster, B; Naik, P; Nakada, T; Nandakumar, R; Nasteva, I; Needham, M; Neufeld, N; Nguyen, A D; Nguyen, T D; Nguyen-Mau, C; Nicol, M; Niess, V; Niet, R; Nikitin, N; Nikodem, T; Nisar, S; Nomerotski, A; Novoselov, A; Oblakowska-Mucha, A; Obraztsov, V; Oggero, S; Ogilvy, S; Okhrimenko, O; Oldeman, R; Orlandea, M; Otalora Goicochea, J M; Owen, P; Pal, B K; Palano, A; Palutan, M; Panman, J; Papanestis, A; Pappagallo, M; Parkes, C; Parkinson, C J; Passaleva, G; Patel, G D; Patel, M; Patrick, G N; Patrignani, C; Pavel-Nicorescu, C; Pazos Alvarez, A; Pellegrino, A; Penso, G; Pepe Altarelli, M; Perazzini, S; Perego, D L; Perez Trigo, E; Pérez-Calero Yzquierdo, A; Perret, P; Perrin-Terrin, M; Pessina, G; Petridis, K; Petrolini, A; Phan, A; Picatoste Olloqui, E; Pietrzyk, B; Pilař, T; Pinci, D; Playfer, S; Plo Casasus, M; Polci, F; Polok, G; Poluektov, A; Polycarpo, E; Popov, D; Popovici, B; Potterat, C; Powell, A; Prisciandaro, J; Pugatch, V; Puig Navarro, A; Qian, W; Rademacker, J H; Rakotomiaramanana, B; Rangel, M S; Raniuk, I; Rauschmayr, N; Raven, G; Redford, S; Reid, M M; dos Reis, A C; Ricciardi, S; Richards, A; Rinnert, K; Rives Molina, V; Roa Romero, D A; Robbe, P; Rodrigues, E; Rodriguez Perez, P; Rogers, G J; Roiser, S; Romanovsky, V; Romero Vidal, A; Rouvinet, J; Ruf, T; Ruiz, H; Sabatino, G; Saborido Silva, J J; Sagidova, N; Sail, P; Saitta, B; Salzmann, C; Sanmartin Sedes, B; Sannino, M; Santacesaria, R; Santamarina Rios, C; Santovetti, E; Sapunov, M; Sarti, A; Satriano, C; Satta, A; Savrie, M; Savrina, D; Schaack, P; Schiller, M; Schindler, H; Schleich, S; Schlupp, M; Schmelling, M; Schmidt, B; Schneider, O; Schopper, A; Schune, M -H; Schwemmer, R; Sciascia, B; Sciubba, A; Seco, M; Semennikov, A; Senderowska, K; Sepp, I; Serra, N; Serrano, J; Seyfert, P; Shapkin, M; Shapoval, I; Shatalov, P; Shcheglov, Y; Shears, T; Shekhtman, L; Shevchenko, O; Shevchenko, V; Shires, A; Silva Coutinho, R; Skwarnicki, T; Smith, N A; Smith, E; Smith, M; Sobczak, K; Sokoloff, M D; Soler, F J P; Soomro, F; Souza, D; Souza De Paula, B; Spaan, B; Sparkes, A; Spradlin, P; Stagni, F; Stahl, S; Steinkamp, O; Stoica, S; Stone, S; Storaci, B; Straticiuc, M; Straumann, U; Subbiah, V K; Swientek, S; Syropoulos, V; Szczekowski, M; Szczypka, P; Szumlak, T; T'Jampens, S; Teklishyn, M; Teodorescu, E; Teubert, F; Thomas, C; Thomas, E; van Tilburg, J; Tisserand, V; Tobin, M; Tolk, S; Tonelli, D; Topp-Joergensen, S; Torr, N; Tournefier, E; Tourneur, S; Tran, M T; Tresch, M; Tsaregorodtsev, A; Tsopelas, P; Tuning, N; Ubeda Garcia, M; Ukleja, A; Urner, D; Uwer, U; Vagnoni, V; Valenti, G; Vazquez Gomez, R; Vazquez Regueiro, P; Vecchi, S; Velthuis, J J; Veltri, M; Veneziano, G; Vesterinen, M; Viaud, B; Vieira, D; Vilasis-Cardona, X; Vollhardt, A; Volyanskyy, D; Voong, D; Vorobyev, A; Vorobyev, V; Voß, C; Voss, H; Waldi, R; Wallace, R; Wandernoth, S; Wang, J; Ward, D R; Watson, N K; Webber, A D; Websdale, D; Whitehead, M; Wicht, J; Wiechczynski, J; Wiedner, D; Wiggers, L; Wilkinson, G; Williams, M P; Williams, M; Wilson, F F; Wishahi, J; Witek, M; Wotton, S A; Wright, S; Wu, S; Wyllie, K; Xie, Y; Xing, F; Xing, Z; Yang, Z; Young, R; Yuan, X; Yushchenko, O; Zangoli, M; Zavertyaev, M; Zhang, F; Zhang, L; Zhang, W C; Zhang, Y; Zhelezov, A; Zhong, L; Zvyagin, A

2013-01-01

The branching fraction of the rate decay $B^0 \\rightarrow K^{*0}e^+e^-$ in the dilepton mass region from 30 to 1000 MeV$/c^2$ has been measured by the LHCb experiment, using $pp$ collision data, corresponding to an integrated luminosity of 1.0 fb$^{-1}$, at a centre-of-mass energy of 7 TeV. The decay mode $B^0 \\rightarrow J/\\psi(e^+e^-) K^{*0}$ is utilized as a normalization channel. The branching fraction $B^0 \\rightarrow K^{*0}e^+e^-$ is measured to be $$ B(B^0 \\rightarrow K^{*0}e^+e^-)^{30-1000 MeV/c^2}= (3.1\\, ^{+0.9\\mbox{} +0.2}_{-0.8\\mbox{}-0.3} \\pm 0.2)\\times 10^{-7}, $$ where the first error is statistical, the second is systematic, and the third comes from the uncertainties on the $B^0 \\rightarrow J/\\psi K^{*0}$ and $J/\\psi \\rightarrow e^+e^- $ branching fractions.

Assignment of multipolarity for ΔI= 0 γ transitions from polarization measurements

International Nuclear Information System (INIS)

Ali, Sajad; Rajbanshi, S.; Chattopadhyay, S.

2017-01-01

It is well known that the determination of the polarization for the γ transition will lead to the unique spin-parity assignments of the nuclear states. The electric and magnetic nature of the γ-rays are distinguishes by the direction of the electric vector of electromagnetic radiation with respect to the beam detector plane. The difference between the perpendicular and parallely scattered events due to the Compton scattering depends on the direction of electric vector of the emitted γ radiation. The difference is positive for electric type transition and negative for magnetic type transitions while for a mixed transitions it is almost zero. However, for the ΔI =0 γ transitions it can be shown theoretically that the difference is positive for magnetic type of transitions and negative for electric type of transitions. This opposite results of the polarization asymmetry for the ΔI =0 γ transitions may sometimes resulted in different assignments of the nuclear states

Emission of β+ Particles Via Internal Pair Production in the 0+ – 0+ Transition of 90Zr: Historical Background and Current Applications in Nuclear Medicine Imaging

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Marco D'Arienzo

2013-03-01

Full Text Available 90Y is traditionally considered as a pure β– emitter. However, the decay of this radionuclide has a minor branch to the 0+ first excited state of 90Zr at 1.76 MeV, that is followed by a β+/β– emission. This internal pair production has been largely studied in the past because it is generated by a rare electric monopole transition (E0 between the states 0+/0+ of 90Zr. The positronic emission has been recently exploited for nuclear medicine applications, i.e. positron emission tomography (PET acquisitions of 90Y-labelled radiopharmaceuticals, widely used as therapeutic agents in internal radiation therapy. To date, this topic is gaining increasing interest in the radiation dosimetry community, as the possibility of detecting β+ emissions from 90Y by PET scanners may pave the way for an accurate patient-specific dosimetry. This could lead to an explosion in scientific production in this field. In the present paper the historical background behind the study of the internal pair production of the 0+/0+ transition of 90Zr is presented along with most up to date measured branch ratio values. An overview of most recent studies that exploit β+ particles emitted from 90Y for PET acquisitions is also provided.

ω→π0γ* and ϕ→π0γ* transition form factors in dispersion theory

Science.gov (United States)

Schneider, Sebastian P.; Kubis, Bastian; Niecknig, Franz

2012-09-01

We calculate the ω→π0γ* and ϕ→π0γ* electromagnetic transition form factors based on dispersion theory, relying solely on a previous dispersive analysis of the corresponding three-pion decays and the pion vector form factor. We compare our findings to recent measurements of the ω→π0μ+μ- decay spectrum by the NA60 collaboration, and strongly encourage experimental investigation of the Okubo-Zweig-Iizuka forbidden ϕ→π0ℓ+ℓ- decays in order to understand the strong deviations from vector-meson dominance found in these transition form factors.

Generalized Michailov plot analysis of inband E2 transitions of deformed nuclei

International Nuclear Information System (INIS)

Long, G.L.; Zhang, W.L.; Ji, H.Y.; Gao, J.F.

1998-01-01

Intraband E2 transitions of some 30 deformed nuclei are analysed using a generalized Michailov plot, based on an E2 transition formula in the SU(3) limit of the sdg interacting boson model. The general E2 transition formula in the sdg-IBM has an L(L+3) term in addition to the usual SU(3) model result. It is found that the general E2 formula can describe the inband transitions well. Comparisons with other models are made. The implications of the results are also discussed. (author)

μ+e-↔μ-e+ transitions via neutral scalar bosons

International Nuclear Information System (INIS)

Hou, W.; Wong, G.

1996-01-01

With μ→eγ decay forbidden by multiplicative lepton number conservation, we study muonium-antimuonium transitions induced by neutral scalar bosons. Pseudoscalars do not induce conversion for triplet muonium, while, for singlet muonium, pseudoscalar and scalar contributions add constructively. This is in contrast with the usual case of doubly charged scalar exchange, where the conversion rate is the same for both singlet and triplet muonium. Complementary to muonium conversion studies, high energy μ + e - →μ - e + and e - e - →μ - μ - collisions could reveal spectacular resonance peaks for the cases of neutral and doubly charged scalars, respectively. copyright 1996 The American Physical Society

Spin canting and magnetic transition in NixZn1-xFe2O4 (x=0.0, 0.5 and 1.0) nanoparticles

Science.gov (United States)

Rani, Stuti; Raghav, Dharmendra Singh; Yadav, Prashant; Varma, G. D.

2018-04-01

Nanoparticles of NixZn1-xFe2O4(x=0.0, 0.5 and 1.0) have been synthesized via co-precipitation method and studied thestructural and magnetic properties. Rietveld refinement of X ray diffraction data of as synthesized samples revealthat the samples have mixed spinel structure with space group Fd-3m. The lattice parameter of the samples decreases as doping concentration of Ni ions increases. Magnetic measurements show paramagnetic to ferrimagnetic transition at room temperature on Ni doping in ZnFe2O4 nanoparticles. The magnetic measurements also show spin canting in samples possibly due to their nanocrystalline nature. The spin canting angles have been calculated with the help of Yafet-Kittel (Y-K) model. Furthermore, the Law of approach (LA) fitting of M-H curves indicates that the samples are highly anisotropicin nature. The Arrot plots of as synthesized samples also indicate the paramagnetic to ferrimagnetic transition. The correlation between the structural and observed magnetic properties of NixZn1-xFe2O4(x=0.0, 0.5 and 1.0) nanocrystals will be described and discussed in this paper.

A transition radiation detector for RHIC featuring accurate tracking and dE/dx particle identification

Energy Technology Data Exchange (ETDEWEB)

O`Brien, E.; Lissauer, D.; McCorkle, S.; Polychronakos, V.; Takai, H. [Brookhaven National Lab., Upton, NY (United States); Chi, C.Y.; Nagamiya, S.; Sippach, W.; Toy, M.; Wang, D.; Wang, Y.F.; Wiggins, C.; Willis, W. [Columbia Univ., New York, NY (United States); Cherniatin, V.; Dolgoshein, B. [Moscow Institute of Physics and Engineering, (Russian Federation); Bennett, M.; Chikanian, A.; Kumar, S.; Mitchell, J.T.; Pope, K. [Yale Univ., New Haven, CT (United States)

1991-12-31

We describe the results of a test ran involving a Transition Radiation Detector that can both distinguish electrons from pions which momenta greater titan 0.7 GeV/c and simultaneously track particles passing through the detector. The particle identification is accomplished through a combination of the detection of Transition Radiation from the electron and the differences in electron and pion energy loss (dE/dx) in the detector. The dE/dx particle separation is most, efficient below 2 GeV/c while particle ID utilizing Transition Radiation effective above 1.5 GeV/c. Combined, the electron-pion separation is-better than 5 {times} 10{sup 2}. The single-wire, track-position resolution for the TRD is {approximately}230 {mu}m.

Simple relations for the excitation energies E2 and the transition probabilities B (E2) of neighboring doubly even nuclides

International Nuclear Information System (INIS)

Patnaik, R.; Patra, R.; Satpathy, L.

1975-01-01

For even-even nuclei, the excitation energy E2 and the reduced transition probability B (E2) between the ground state and the first excited 2 + state have been considered. On the basis of different models, it is shown that for a nucleus N, Z the relations E2N, Z + E2N + 2,Z + 2 - E2N + 2, Z - E2N, Z + 2 approx. = 0 and B (E2)N, Z + B (E2)N + 2,Z + 2 - B (E2)N + 2,Z - B (E2)N, Z + 2 approx. = 0 hold good, except in certain specified regions. The goodness of these difference equations is tested with the available experimental data. The difference equation of Ross and Bhaduri is shown to follow from our approach. Some predictions of unmeasured E2 and B (E2) values have been made

Q2 Dependence of Quadrupole Strength in the gamma*p-->Delta+(1232) --> p pi0 Transition

International Nuclear Information System (INIS)

Volker Burkert; Kyungseon Joo; Lee Smith; Ralph Minehart

2002-01-01

Models of baryon structure predict a small quadrupole deformation of the nucleon due to residual tensor forces between quarks or distortions from the pion cloud. Sensitivity to quark versus pion degrees of freedom occurs through the Q 2 dependence of the magnetic (M 1+ ), electric (E 1+ ), and scalar (S 1+ ) multipoles in the γ*p → Δ + (1232) → pπ 0 transition. New precision measurements of the ratios E 1+ /M 1+ and S 1+ /M 1+ are reported here over the range Q 2 = 0.4-1.8 GeV 2 . Results are best described by recent unitary models in which the pion cloud plays a dominant role

An investigation on phase transition behaviors in MgO-doped Pb{sub 0.99}(Zr{sub 0.95}Ti{sub 0.05}){sub 0.98}Nb{sub 0.02}O{sub 3} ferroelectric ceramics by Raman and dielectric measurements

Energy Technology Data Exchange (ETDEWEB)

Wang, Junxia, E-mail: wjunxia2002@163.com [Key Laboratory of Inorganic Functional Materials and Devices, Shanghai Institute of Ceramics, Chinese Academy of Sciences, Shanghai 200050 (China); State Key Laboratory Cultivation Base for Nonmetal Composites and Functional Materials, Southwest University of Science and Technology, Mianyang 621010 (China); Wang, Genshui; Chen, Xuefeng [Key Laboratory of Inorganic Functional Materials and Devices, Shanghai Institute of Ceramics, Chinese Academy of Sciences, Shanghai 200050 (China); Hu, Zhigao [Key Laboratory of Polar Materials and Devices, Ministry of Education, Department of Electronic Engineering, East China Normal University, Shanghai 200241 (China); Nie, Hengchang; Cao, Fei [Key Laboratory of Inorganic Functional Materials and Devices, Shanghai Institute of Ceramics, Chinese Academy of Sciences, Shanghai 200050 (China); Dong, Xianlin, E-mail: xldong@mail.sic.ac.cn [Key Laboratory of Inorganic Functional Materials and Devices, Shanghai Institute of Ceramics, Chinese Academy of Sciences, Shanghai 200050 (China)

2015-03-15

Highlights: • The phase transition behaviors were strongly dependent on MgO concentration. • The F{sub R(LT)}–F{sub R(HT)} phase transition temperature obviously shifted toward a lower temperature with increasing MgO addition. • The F{sub R(HT)}–cubic paraelectric (P{sub C}) phase transition changed to a higher temperature with increasing MgO addition. • The distortion of BO{sub 6} oxygen octahedron caused by B-site replacement of Mg{sup 2+} ions is proposed to explain the observed behaviors. • Superior room-temperature pyroelectric properties were obtained in 0.1 wt% MgO-modified PZTN 95/5 ceramics during F{sub R(LT)}–F{sub R(HT)} phase transition. - Abstract: The phase transition behaviors of Pb{sub 0.99}(Zr{sub 0.95}Ti{sub 0.05}){sub 0.98}Nb{sub 0.02}O{sub 3} ferroelectric ceramics doped with different MgO concentrations (0–0.2 wt%) were systematically investigated by Raman and dielectric measurements. Raman results showed that the phase transitions were strongly dependent on MgO concentration. It was found that the low temperature rhombohedral (F{sub R(LT)})–high temperature rhombohedral (F{sub R(HT)}) ferroelectric phase transition shifted toward a lower temperature with increasing MgO concentration up to 0.1 wt%, while the F{sub R(HT)}–cubic paraelectric (P{sub C}) phase transition changed to a higher temperature. The Raman results were in good agreement with phase transition determined by dielectric measurements. Moreover, it was indicated that the changes of Raman active modes were related to distortion of BO{sub 6} octahedra during the phase transitions. Then, the distortion of BO{sub 6} octahedron caused by B-site replacement of Mg{sup 2+} ions was proposed to explain the observed behaviors. In addition, the effects of MgO doping on the dielectric, ferroelectric and pyroelectric properties were also discussed.

Study of an Isospin-Forbidden $0^{+} \\rightarrow 0^{+}$ Transition in $^{38m}$K

CERN Multimedia

2002-01-01

There is at present a discrepancy between the precisely determined value of $V_{ud}^{2}$ obtained from $0^{+} \\rightarrow 0^{+} $ nuclear $\\beta$-decay and the less precisely determined value inferred from neutron decay. One possible explanation for this discrepancy involves the " Coulomb " corrections that must be applied to the nuclear decay rates. We propose to investigate one class of these corrections (for charge-dependent configuration-mixing) by measuring the isospin-forbidden $0^{+} \\rightarrow 0^{+}$ decay rate in $^{38m}$K. $^{38m}$K decay is particularly interesting because it is predicted to have the largest charge-dependent mixing correction of any of the transitions used in the $V_{ud}^{2}$ determination.

Origin of the strain glass transition in Ti_5_0(Ni_5_0_−_x D_x) alloys

International Nuclear Information System (INIS)

Wang, Xu; Shang, Jia-Xiang; Wang, Fu-He; Chen, Yue

2016-01-01

Direct evidence was recently discovered for the unique strain glass (STG) transition, which breaks the local symmetries (PRL 112, 025701 (2014)). To understand the origin of the STG transition, the effects of doping point defects on Ti_5_0(Ni_5_0_−_x D_x) are investigated using first-principle calculations. The experimental observation that STG only exists in a limited range of chemical composition x is successfully rationalized. The mechanisms that correspond to the division of a system into domains with distinctly different compositions are found to be directly related to a dip in the defect formation energy. - Highlights: • The strain glass transition phenomenon in Ti−Ni-based alloys is rationalized. • The electronic-structure origins of the strain glass transition are uncovered. • The separation of domains with different compositions is explained.

Thermotropic phase transitions in Pb{sub 1−x}Sr{sub x}(Al{sub 1/3}Nb{sub 2/3}){sub 0.1}(Zr{sub 0.52}Ti{sub 0.48}){sub 0.9}O{sub 3} ceramics: Temperature dependent dielectric permittivity and Raman scattering

Energy Technology Data Exchange (ETDEWEB)

Li, C. Q.; Peng, L.; Jiang, K.; Hu, Z. G., E-mail: zghu@ee.ecnu.edu.cn; Chu, J. H. [Key Laboratory of Polar Materials and Devices, Ministry of Education, Department of Electronic Engineering, East China Normal University, Shanghai 200241 (China); Wang, P.; Liu, A. Y. [Department of Physics, Shanghai Normal University, Shanghai 200234 (China)

2015-06-15

The phase transitions of Pb{sub 1−x}Sr{sub x}(Al{sub 1/3}Nb{sub 2/3}){sub 0.1}(Zr{sub 0.52}Ti{sub 0.48}){sub 0.9}O{sub 3} (Sr-modified PAN-PZT) ceramics with Sr compositions of x = 2%, 5%, 10% and 15% have been investigated using X-ray diffraction (XRD), temperature dependent dielectric permittivity and Raman scattering. The XRD analysis show that the phase transition occurs between Sr composition of 5% and 10%. Based on the broad dielectric peaks at 100 Hz, the diffused phase transition from tetragonal (T) to cubic (C) structure shifts to lower temperature with increasing Sr composition. The dramatic changes of wavenumber and full width at half-maximum (FWHM) for E(TO{sub 4})′ softing mode can be observed at morphotropic phase boundary (MPB). Moreover, the MPB characteristic shows a wider and lower trend of temperature region with increasing Sr composition. It could be ascribed to the diminishment of the energy barrier and increment of A-cation entropy. Therefore, the Sr-modified PAN-PZT ceramics unambiguously undergo two successive structural transitions (rhombohedral-tetragonal-cubic phase) with temperature from 80 to 750 K. Correspondingly, the phase diagram of Sr-modified PAN-PZT ceramics can be well depicted.

The β+ decay of 234Np and other isospin-forbidden 0+ -> 0+ Fermi transitions

International Nuclear Information System (INIS)

Yap, C.T.; Saw, E.L.

1984-01-01

Although experimental values of the Fermi nuclear matrix elements vary widely from about 1x10 -3 to 40x10 -3 for isospin-forbidden 0 + ->0 + β transitions, theoretical calculations using the Coulomb potential and Nilsson wave functions yielded values of Msub(F) in reasonably good agreement, except that of 234 Np. However, our calculation of Msub(F) for this decay as a function of the deformation parameter β yielded a value of Msub(F) in good agreement with experiment for values of β between 0.1 and 0.2. (orig.)

A comparative study of magnetic field induced meta-magnetic transition in nanocrystalline and bulk Pr0.65(Ca0.7Sr0.3)0.35MnO3 compound

Science.gov (United States)

Saha, Suvayan; Das, Kalipada; Bandyopadhyay, Sudipta; Das, I.

2017-06-01

In our present study we highlight the observations of external magnetic field induced sharp meta-magnetic transition in polycrystalline bulk as well as nanocrystalline form of Pr0.65(Ca0.7Sr0.7)0.35MnO3 compound. Interestingly, such behavior persists in the nanoparticles regardless of the disorder broadened transition. However, higher magnetic field is required for nanoparticles having average particle size ∼40 nm for such meta-magnetic transition, which differs from the general trends of the pure charge ordered nano materials. The interfacial strain between the different magnetic domains plays the important role in magnetic isothermal properties of nanoparticles, when the samples are cooled down in different cooling field. Additionally, both the bulk and nanoparticle compounds exhibit spontaneous phase separation and significantly large magnetoresistance at the low temperature region due to the melting of charge ordered fraction.

Observation of a Neutral Charmoniumlike State Z(c)(0) in e(+)e(-) -> (D*(D)over-bar*)(0)pi(0)

NARCIS (Netherlands)

Ablikim, M.; Achasov, M. N.; Ai, X. C.; Albayrak, O.; Albrecht, M.; Ambrose, D. J.; Amoroso, A.; An, F. F.; An, Q.; Bai, J. Z.; Ferroli, R. Baldini; Ban, Y.; Bennett, D. W.; Bennett, J. V.; Bertani, M.; Bettoni, D.; Bian, J. M.; Bianchi, F.; Boger, E.; Boyko, I.; Briere, R. A.; Cai, H.; Cai, X.; Cakir, O.; Calcaterra, A.; Cao, G. F.; Cetin, S. A.; Chang, J. F.; Chelkov, G.; Chen, G.; Chen, H. S.; Chen, H. Y.; Chen, J. C.; Chen, M. L.; Chen, S. J.; Chen, X.; Chen, X. R.; Chen, Y. B.; Cheng, H. P.; Chu, X. K.; Cibinetto, G.; Dai, H. L.; Dai, J. P.; Dbeyssi, A.; Dedovich, D.; Deng, Z. Y.; Denig, A.; Denysenko, I.; Destefanis, M.; De Mori, F.; Ding, Y.; Dong, C.; Dong, J.; Dong, L. Y.; Dong, M. Y.; Du, S. X.; Duan, P. F.; Eren, E. E.; Fan, J. Z.; Fang, J.; Fang, S. S.; Fang, X.; Fang, Y.; Fava, L.; Feldbauer, F.; Felici, G.; Feng, C. Q.; Fioravanti, E.; Fritsch, M.; Fu, C. D.; Gao, Q.; Gao, X. Y.; Gao, Y.; Gao, Z.; Garzia, I.; Geng, C.; Goetzen, K.; Gong, W. X.; Gradl, W.; Greco, M.; Gu, M. H.; Gu, Y. T.; Guan, Y. H.; Guo, A. Q.; Guo, L. B.; Guo, Y.; Guo, Y. P.; Haddadi, Z.; Hafner, A.; Han, S.; Han, Y. L.; Hao, X. Q.; Harris, F. A.; He, K. L.; He, Z. Y.; Held, T.; Heng, Y. K.; Hou, Z. L.; Hu, C.; Hu, H. M.; Hu, J. F.; Hu, T.; Hu, Y.; Huang, G. M.; Huang, G. S.; Huang, H. P.; Huang, J. S.; Huang, X. T.; Huang, Y.; Hussain, T.; Ji, Q.; Ji, Q. P.; Ji, X. B.; Ji, X. L.; Jiang, L. L.; Jiang, L. W.; Jiang, X. S.; Jiang, X. Y.; Jiao, J. B.; Jiao, Z.; Jin, D. P.; Jin, S.; Johansson, T.; Julin, A.; Kalantar-Nayestanaki, N.; Kang, X. L.; Kang, X. S.; Kavatsyuk, M.; Ke, B. C.; Kiese, P.; Kliemt, R.; Kloss, B.; Kolcu, O. B.; Kopf, B.; Kornicer, M.; Kuehn, W.; Kupsc, A.; Lange, J. S.; Lara, M.; Larin, P.; Leng, C.; Li, C.; Li, C. H.; Li, Cheng; Li, D. M.; Li, F.; Li, G.; Li, H. B.; Li, J. C.; Li, Jin; Li, K.; Li, K.; Li, Lei; Li, P. R.; Li, T.; Li, W. D.; Li, W. G.; Li, X. L.; Li, X. M.; Li, X. N.; Li, X. Q.; Li, Z. B.; Liang, H.; Liang, Y. F.; Liang, Y. T.; Liao, G. R.; Lin, D. X.; Liu, B. J.; Liu, C. X.; Liu, F. H.; Liu, Fang; Liu, Feng; Liu, H. B.; Liu, H. H.; Liu, H. H.; Liu, H. M.; Liu, J.; Liu, J. B.; Liu, J. P.; Liu, J. Y.; Liu, K.; Liu, K. Y.; Liu, L. D.; Liu, P. L.; Liu, Q.; Liu, S. B.; Liu, X.; Liu, X. X.; Liu, Y. B.; Liu, Z. A.; Liu, Zhiqiang; Liu, Zhiqing; Loehner, H.; Lou, X. C.; Lu, H. J.; Lu, J. G.; Lu, R. Q.; Lu, Y.; Lu, Y. P.; Luo, C. L.; Luo, M. X.; Luo, T.; Luo, X. L.; Lv, M.; Lyu, X. R.; Ma, F. C.; Ma, H. L.; Ma, L. L.; Ma, Q. M.; Ma, T.; Ma, X. N.; Ma, X. Y.; Maas, F. E.; Maggiora, M.; Mao, Y. J.; Mao, Z. P.; Marcello, S.; Messchendorp, J. G.; Min, J.; Min, T. J.; Mitchell, R. E.; Mo, X. H.; Mo, Y. J.; Morales, C. Morales; Moriya, K.; Muchnoi, N. Yu.; Muramatsu, H.; Nefedov, Y.; Nerling, F.; Nikolaev, I. B.; Ning, Z.; Nisar, S.; Niu, S. L.; Niu, X. Y.; Olsen, S. L.; Ouyang, Q.; Pacetti, S.; Patteri, P.; Pelizaeus, M.; Peng, H. P.; Peters, K.; Pettersson, J.; Ping, J. L.; Ping, R. G.; Poling, R.; Prasad, V.; Pu, Y. N.; Qi, M.; Qian, S.; Qiao, C. F.; Qin, L. Q.; Qin, N.; Qin, X. S.; Qin, Y.; Qin, Z. H.; Qiu, J. F.; Rashid, K. H.; Redmer, C. F.; Ren, H. L.; Ripka, M.; Rong, G.; Rosner, Ch.; Ruan, X. D.; Santoro, V.; Sarantsev, A.; Savrie, M.; Schoenning, K.; Schumann, S.; Shan, W.; Shao, M.; Shen, C. P.; Shen, P. X.; Shen, X. Y.; Sheng, H. Y.; Song, W. M.; Song, X. Y.; Sosio, S.; Spataro, S.; Sun, G. X.; Sun, J. F.; Sun, S. S.; Sun, Y. J.; Sun, Y. Z.; Sun, Z. J.; Sun, Z. T.; Tang, C. J.; Tang, X.; Tapan, I.; Thorndike, E. H.; Tiemens, M.; Ullrich, M.; Uman, I.; Varner, G. S.; Wang, B.; Wang, B. L.; Wang, D.; Wang, D. Y.; Wang, K.; Wang, L. L.; Wang, L. S.; Wang, M.; Wang, P.; Wang, P. L.; Wang, S. G.; Wang, W.; Wang, X. F.; Wang, Y. D.; Wang, Y. F.; Wang, Y. Q.; Wang, Z.; Wang, Z. G.; Wang, Z. H.; Wang, Z. Y.; Weber, T.; Wei, D. H.; Wei, J. B.; Weidenkaff, P.; Wen, S. P.; Wiedner, U.; Wolke, M.; Wu, L. H.; Wu, Z.; Xia, L. G.; Xia, Y.; Xiao, D.; Xiao, Z. J.; Xie, Y. G.; Xiu, Q. L.; Xu, G. F.; Xu, L.; Xu, Q. J.; Xu, Q. N.; Xu, X. P.; Yan, L.; Yan, W. B.; Yan, W. C.; Yan, Y. H.; Yang, H. J.; Yang, H. X.; Yang, L.; Yang, Y.; Yang, Y. X.; Ye, H.; Ye, M.; Ye, M. H.; Yin, J. H.; Yu, B. X.; Yu, C. X.; Yu, H. W.; Yu, J. S.; Yuan, C. Z.; Yuan, W. L.; Yuan, Y.; Yuncu, A.; Zafar, A. A.; Zallo, A.; Zeng, Y.; Zhang, B. X.; Zhang, B. Y.; Zhang, C.; Zhang, C. C.; Zhang, D. H.; Zhang, H. H.; Zhang, H. Y.; Zhang, J. J.; Zhang, J. L.; Zhang, J. Q.; Zhang, J. W.; Zhang, J. Y.; Zhang, J. Z.; Zhang, K.; Zhang, L.; Zhang, S. H.; Zhang, X. Y.; Zhang, Y.; Zhang, Y. N.; Zhang, Y. H.; Zhang, Y. T.; Zhang, Yu; Zhang, Z. H.; Zhang, Z. P.; Zhang, Z. Y.; Zhao, G.; Zhao, J. W.; Zhao, J. Y.; Zhao, J. Z.; Zhao, Lei; Zhao, Ling; Zhao, M. G.; Zhao, Q.; Zhao, Q. W.; Zhao, S. J.; Zhao, T. C.; Zhao, Y. B.; Zhao, Z. G.; Zhemchugov, A.; Zheng, B.; Zheng, J. P.; Zheng, W. J.; Zheng, Y. H.; Zhong, B.; Zhou, L.; Zhou, Li; Zhou, X.; Zhou, X. K.; Zhou, X. R.; Zhou, X. Y.; Zhu, K.; Zhu, K. J.; Zhu, S.; Zhu, X. L.; Zhu, Y. C.; Zhu, Y. S.; Zhu, Z. A.; Zhuang, J.; Zotti, L.; Zou, B. S.; Zou, J. H.

2015-01-01

We report a study of the process e(+)e(-) -> (D*(D) over bar*)(0)pi(0) using e(+)e(-) collision data samples with integrated luminosities of 1092 pb(-1) at root s = 4.23 GeV and 826 pb(-1) at root s = 4.26 GeV collected with the BESIII detector at the BEPCII storage ring. We observe a new neutral

E3-transitions in sup(105, 107, 109, 111)Ag

International Nuclear Information System (INIS)

Shevelev, G.A.; Troitskaya, A.G.; Kartashov, V.M.

1978-01-01

Electron radiation of the isomeric transitions of the sup(105-111)Ag odd nuclei was studied using an iron magnetic πsup(√2) beta spectrometer. For most isomeric transitions, relative intensities of the K, L, M, and N lines have been measured; for sup(105-111)Ag and 111 Cd they were measured for the first time. Energy of gamma transitions, relative intensities of internal conversion electrons (ICE) compared with the theoretical ICE values for the E3 transitions are presented. The observations for all the shells are in a fairly gool agreement with the calculations. Systematics of low-lying excited states of the silver nuclei involved is proposed. It has been established that spins and parities of the first excited states of the sup(105-111)Ag odd nuclei are 7/2 + . Multipolarities of isomeric transitions from these staes are pure E3. Spin and parity 9/2 + of the second excited states may be uniquely determined unly for 109 Ag from direct measurements of the ICE transition at 45.8 keV

Meson-exchange enhancement of the first forbidden $0^{+} \\leftrightarrow 0^{-} \\beta$-transitions

CERN Multimedia

2002-01-01

In the frame of the standard model of the weak interaction, it has been suggested by Kubodera, Delorme and Rho, that pion exchange should have a large effect on the rank-zero time-like component of the axial current A$_{0}$. The best case for the study of A$ _{0}$ is $0^{-} \\leftrightarrow 0^{+} \\beta$-decay since in this process only rank zero matrix elements of the time-like and space-like components of the axial current contribute to the transition rate. $0^{-} \\leftrightarrow 0^{+}$ decays have been studied in the vicinity of doubly closed-shell nuclei such as $^{16}$O, $^{96}$Zr, and $^{208}$Pb where s$_{1/2} \\leftrightarrow$ p$_{1/2}$ matrix elements were involved. In these cases, the meson-exchange correction to the one-body axial-charge density is significant. ISOLDE offers the possibility to perform sensitive measurements of the $0^{-} \\leftrightarrow 0^{+}$ pseudoscalar decay in nuclei where the p$_{3/2} \\rightarrow$ d$_{3/2}$ matrix elements are involved. We therefore propose a search of the $^{38}...

Search for the rare decays J /ψ →D0e+e-+c .c . and ψ (3686 )→D0e+e-+c .c .

Science.gov (United States)

Ablikim, M.; Achasov, M. N.; Ahmed, S.; Albrecht, M.; Amoroso, A.; An, F. F.; An, Q.; Bai, J. Z.; Bakina, O.; Baldini Ferroli, R.; Ban, Y.; Bennett, D. W.; Bennett, J. V.; Berger, N.; Bertani, M.; Bettoni, D.; Bian, J. M.; Bianchi, F.; Boger, E.; Boyko, I.; Briere, R. A.; Cai, H.; Cai, X.; Cakir, O.; Calcaterra, A.; Cao, G. F.; Cetin, S. A.; Chai, J.; Chang, J. F.; Chelkov, G.; Chen, G.; Chen, H. S.; Chen, J. C.; Chen, M. L.; Chen, S. J.; Chen, X. R.; Chen, Y. B.; Chu, X. K.; Cibinetto, G.; Dai, H. L.; Dai, J. P.; Dbeyssi, A.; Dedovich, D.; Deng, Z. Y.; Denig, A.; Denysenko, I.; Destefanis, M.; de Mori, F.; Ding, Y.; Dong, C.; Dong, J.; Dong, L. Y.; Dong, M. Y.; Dorjkhaidav, O.; Dou, Z. L.; Du, S. X.; Duan, P. F.; Fang, J.; Fang, S. S.; Fang, X.; Fang, Y.; Farinelli, R.; Fava, L.; Fegan, S.; Feldbauer, F.; Felici, G.; Feng, C. Q.; Fioravanti, E.; Fritsch, M.; Fu, C. D.; Gao, Q.; Gao, X. L.; Gao, Y.; Gao, Y. G.; Gao, Z.; Garzia, I.; Goetzen, K.; Gong, L.; Gong, W. X.; Gradl, W.; Greco, M.; Gu, M. H.; Gu, S.; Gu, Y. T.; Guo, A. Q.; Guo, L. B.; Guo, R. P.; Guo, Y. P.; Haddadi, Z.; Hafner, A.; Han, S.; Hao, X. Q.; Harris, F. A.; He, K. L.; He, X. Q.; Heinsius, F. H.; Held, T.; Heng, Y. K.; Holtmann, T.; Hou, Z. L.; Hu, C.; Hu, H. M.; Hu, T.; Hu, Y.; Huang, G. S.; Huang, J. S.; Huang, X. T.; Huang, X. Z.; Huang, Z. L.; Hussain, T.; Ikegami Andersson, W.; Ji, Q.; Ji, Q. P.; Ji, X. B.; Ji, X. L.; Jiang, X. S.; Jiang, X. Y.; Jiao, J. B.; Jiao, Z.; Jin, D. P.; Jin, S.; Johansson, T.; Julin, A.; Kalantar-Nayestanaki, N.; Kang, X. L.; Kang, X. S.; Kavatsyuk, M.; Ke, B. C.; Khan, T.; Kiese, P.; Kliemt, R.; Kloss, B.; Koch, L.; Kolcu, O. B.; Kopf, B.; Kornicer, M.; Kuemmel, M.; Kuhlmann, M.; Kupsc, A.; Kühn, W.; Lange, J. S.; Lara, M.; Larin, P.; Lavezzi, L.; Leithoff, H.; Leng, C.; Li, C.; Li, Cheng; Li, D. M.; Li, F.; Li, F. Y.; Li, G.; Li, H. B.; Li, H. J.; Li, J. C.; Li, Jin; Li, Kang; Li, Ke; Li, Lei; Li, P. L.; Li, P. R.; Li, Q. Y.; Li, T.; Li, W. D.; Li, W. G.; Li, X. L.; Li, X. N.; Li, X. Q.; Li, Z. B.; Liang, H.; Liang, Y. F.; Liang, Y. T.; Liao, G. R.; Lin, D. X.; Liu, B.; Liu, B. J.; Liu, C. X.; Liu, D.; Liu, F. H.; Liu, Fang; Liu, Feng; Liu, H. B.; Liu, H. M.; Liu, Huanhuan; Liu, Huihui; Liu, J. B.; Liu, J. P.; Liu, J. Y.; Liu, K.; Liu, K. Y.; Liu, Ke; Liu, L. D.; Liu, P. L.; Liu, Q.; Liu, S. B.; Liu, X.; Liu, Y. B.; Liu, Y. Y.; Liu, Z. A.; Liu, Zhiqing; Long, Y. F.; Lou, X. C.; Lu, H. J.; Lu, J. G.; Lu, Y.; Lu, Y. P.; Luo, C. L.; Luo, M. X.; Luo, T.; Luo, X. L.; Lyu, X. R.; Ma, F. C.; Ma, H. L.; Ma, L. L.; Ma, M. M.; Ma, Q. M.; Ma, T.; Ma, X. N.; Ma, X. Y.; Ma, Y. M.; Maas, F. E.; Maggiora, M.; Malik, Q. A.; Mao, Y. J.; Mao, Z. P.; Marcello, S.; Messchendorp, J. G.; Mezzadri, G.; Min, J.; Min, T. J.; Mitchell, R. E.; Mo, X. H.; Mo, Y. J.; Morales Morales, C.; Morello, G.; Muchnoi, N. Yu.; Muramatsu, H.; Musiol, P.; Mustafa, A.; Nefedov, Y.; Nerling, F.; Nikolaev, I. B.; Ning, Z.; Nisar, S.; Niu, S. L.; Niu, X. Y.; Olsen, S. L.; Ouyang, Q.; Pacetti, S.; Pan, Y.; Papenbrock, M.; Patteri, P.; Pelizaeus, M.; Pellegrino, J.; Peng, H. P.; Peters, K.; Pettersson, J.; Ping, J. L.; Ping, R. G.; Poling, R.; Prasad, V.; Qi, H. R.; Qi, M.; Qian, S.; Qiao, C. F.; Qin, J. J.; Qin, N.; Qin, X. S.; Qin, Z. H.; Qiu, J. F.; Rashid, K. H.; Redmer, C. F.; Richter, M.; Ripka, M.; Rong, G.; Rosner, Ch.; Ruan, X. D.; Sarantsev, A.; Savrié, M.; Schnier, C.; Schoenning, K.; Shan, W.; Shao, M.; Shen, C. P.; Shen, P. X.; Shen, X. Y.; Sheng, H. Y.; Song, J. J.; Song, W. M.; Song, X. Y.; Sosio, S.; Sowa, C.; Spataro, S.; Sun, G. X.; Sun, J. F.; Sun, S. S.; Sun, X. H.; Sun, Y. J.; Sun, Y. K.; Sun, Y. Z.; Sun, Z. J.; Sun, Z. T.; Tang, C. J.; Tang, G. Y.; Tang, X.; Tapan, I.; Tiemens, M.; Tsednee, B. T.; Uman, I.; Varner, G. S.; Wang, B.; Wang, B. L.; Wang, D.; Wang, D. Y.; Wang, Dan; Wang, K.; Wang, L. L.; Wang, L. S.; Wang, M.; Wang, P.; Wang, P. L.; Wang, W. P.; Wang, X. F.; Wang, Y.; Wang, Y. D.; Wang, Y. F.; Wang, Y. Q.; Wang, Z.; Wang, Z. G.; Wang, Z. H.; Wang, Z. Y.; Wang, Zongyuan; Weber, T.; Wei, D. H.; Wei, J. H.; Weidenkaff, P.; Wen, S. P.; Wiedner, U.; Wolke, M.; Wu, L. H.; Wu, L. J.; Wu, Z.; Xia, L.; Xia, Y.; Xiao, D.; Xiao, H.; Xiao, Y. J.; Xiao, Z. J.; Xie, Y. G.; Xie, Y. H.; Xiong, X. A.; Xiu, Q. L.; Xu, G. F.; Xu, J. J.; Xu, L.; Xu, Q. J.; Xu, Q. N.; Xu, X. P.; Yan, L.; Yan, W. B.; Yan, W. C.; Yan, Y. H.; Yang, H. J.; Yang, H. X.; Yang, L.; Yang, Y. H.; Yang, Y. X.; Ye, M.; Ye, M. H.; Yin, J. H.; You, Z. Y.; Yu, B. X.; Yu, C. X.; Yu, J. S.; Yuan, C. Z.; Yuan, Y.; Yuncu, A.; Zafar, A. A.; Zeng, Y.; Zeng, Z.; Zhang, B. X.; Zhang, B. Y.; Zhang, C. C.; Zhang, D. H.; Zhang, H. H.; Zhang, H. Y.; Zhang, J.; Zhang, J. L.; Zhang, J. Q.; Zhang, J. W.; Zhang, J. Y.; Zhang, J. Z.; Zhang, K.; Zhang, L.; Zhang, S. Q.; Zhang, X. Y.; Zhang, Y. H.; Zhang, Y. T.; Zhang, Yang; Zhang, Yao; Zhang, Yu; Zhang, Z. H.; Zhang, Z. P.; Zhang, Z. Y.; Zhao, G.; Zhao, J. W.; Zhao, J. Y.; Zhao, J. Z.; Zhao, Lei; Zhao, Ling; Zhao, M. G.; Zhao, Q.; Zhao, S. J.; Zhao, T. C.; Zhao, Y. B.; Zhao, Z. G.; Zhemchugov, A.; Zheng, B.; Zheng, J. P.; Zheng, W. J.; Zheng, Y. H.; Zhong, B.; Zhou, L.; Zhou, X.; Zhou, X. K.; Zhou, X. R.; Zhou, X. Y.; Zhou, Y. X.; Zhu, K.; Zhu, K. J.; Zhu, S.; Zhu, S. H.; Zhu, X. L.; Zhu, Y. C.; Zhu, Y. S.; Zhu, Z. A.; Zhuang, J.; Zotti, L.; Zou, B. S.; Zou, J. H.; Besiii Collaboration

2017-12-01

Using the data samples of (1310.6 ±7.2 )×106 J /ψ events and (448.1 ±2.9 )×106 ψ (3686 ) events collected with the BESIII detector, we search for the rare decays J /ψ →D0e+e-+c .c . and ψ (3686 )→D0e+e-+c .c . No significant signals are observed and the corresponding upper limits on the branching fractions at the 90% confidence level are determined to be B (J /ψ →D0e+e-+c .c .)<8.5 ×10-8 and B (ψ (3686 )→D0e+e-+c .c .)<1.4 ×10-7 , respectively. Our limit on B (J /ψ →D0e+e-+c .c .) is more stringent by 2 orders of magnitude than the previous results, and B (ψ (3686 )→D0e+e-+c .c .) is measured for the first time.

Pressure dependence of optical transitions in In0.15Ga0.85N/GaN multiple quantum wells

International Nuclear Information System (INIS)

Shan, W.; Ager, J.W. III; Walukiewicz, W.; Haller, E.E.; McCluskey, M.D.; Johnson, N.M.; Bour, D.P.

1998-01-01

The effects of hydrostatic pressure on optical transitions in In 0.15 Ga 0.85 N/GaN multiple quantum wells (MQW close-quote s) have been studied. The optical transition associated with confined electron and hole states in the MQW close-quote s was found to shift linearly to higher energy with pressure but exhibit a significantly weaker pressure dependence compared to bulklike thick epitaxial-layer samples. Similar pressure coefficients obtained by both photomodulation and photoluminescence measurements rule out the possibility of the transition involving localized states deep in the band gap. We found that the difference in the compressibility of In x Ga 1-x N and GaN induces a tensile strain in the compressively strained In x Ga 1-x N well layers, partially compensating the externally applied hydrostatic pressure. This mechanical effect is primarily responsible for the smaller pressure dependence of the optical transitions in the In x Ga 1-x N/GaN MQW close-quote s. In addition, the pressure-dependent measurements allow us to identify a spectral feature observed at an energy below the GaN band gap. We conclude that this feature is due to transitions from ionized Mg acceptor states to the conduction band in the p-type GaN cladding layer rather than a confined transition in the MQW close-quote s. copyright 1998 The American Physical Society

Critical parameters near the ferromagnetic-paramagnetic phase transition in La0.7A0.3(Mn1-xbx)O3 (A=Sr; B=Ti and Al; x=0.0 and 0.05) compounds

International Nuclear Information System (INIS)

Khiem, N.V.; Phong, P.T.; Bau, L.V.; Nam, D.N.H.; Hong, L.V.; Phuc, N.X.

2009-01-01

The critical parameters provide important information concerning the interaction mechanisms near the paramagnetic-to-ferromagnetic transition. In this paper, we present a thorough study for the critical behavior of La 0.7 A 0.3 (Mn 1-x B x )O 3 (A=Sr; B=Ti and Al; x=0.0 and 0.05) polycrystalline samples near ferromagnetic-paramagnetic phase transition temperature by analyzing isothermal magnetization data. We have analyzed our dc-magnetization data near the transition temperature with the help of the modified Arrot plot, Kouvel-Fisher method. We have determined the critical temperature T C and the critical parameters β, γ and δ. With the values of T C , β and γ, we plot Mx(1-T/T C ) -β vs. Hx(1-T/T C ) -γ . All the data collapse on one of the two curves. This suggests that the data below and above T C obey scaling, following a single equation of state. Critical parameters for x=0 and x Ti =0.05 samples are between those predicted for a 3D-Heisenberg model and mean-field theory and for x Al =0.05 samples the values obtained for the critical parameters are close to those predicted by the mean-field theory.

Manipulating multiple order parameters via oxygen vacancies: The case of E u0.5B a0.5Ti O3 -δ

Science.gov (United States)

Li, Weiwei; He, Qian; Wang, Le; Zeng, Huizhong; Bowlan, John; Ling, Langsheng; Yarotski, Dmitry A.; Zhang, Wenrui; Zhao, Run; Dai, Jiahong; Gu, Junxing; Shen, Shipeng; Guo, Haizhong; Pi, Li; Wang, Haiyan; Wang, Yongqiang; Velasco-Davalos, Ivan A.; Wu, Yangjiang; Hu, Zhijun; Chen, Bin; Li, Run-Wei; Sun, Young; Jin, Kuijuan; Zhang, Yuheng; Chen, Hou-Tong; Ju, Sheng; Ruediger, Andreas; Shi, Daning; Borisevich, Albina Y.; Yang, Hao

2017-09-01

Controlling functionalities, such as magnetism or ferroelectricity, by means of oxygen vacancies (VO) is a key issue for the future development of transition-metal oxides. Progress in this field is currently addressed through VO variations and their impact on mainly one order parameter. Here we reveal a mechanism for tuning both magnetism and ferroelectricity simultaneously by using VO. Combining experimental and density-functional theory studies of E u0.5B a0.5Ti O3 -δ , we demonstrate that oxygen vacancies create T i3 +3 d1 defect states, mediating the ferromagnetic coupling between the localized Eu 4 f7 spins, and increase an off-center displacement of Ti ions, enhancing the ferroelectric Curie temperature. The dual function of Ti sites also promises a magnetoelectric coupling in the E u0.5B a0.5Ti O3 -δ .

Isothermal phase transition and the transition temperature limitation in the lead-free (1-x)Bi0.5Na0.5TiO3-xBaTiO3 system

International Nuclear Information System (INIS)

Zhang, Dawei; Yao, Yonggang; Fang, Minxia; Luo, Zhengdong; Zhang, Lixue; Li, Linglong; Cui, Jian; Zhou, Zhijian; Bian, Jihong; Ren, Xiaobing; Yang, Yaodong

2016-01-01

Most ferroelectric transitions occur ultrafast and are time independent. However, here in (1-x) (Bi 0.5 Na 0.5 )TiO 3 -xBaTiO 3 , we have found a ferroelectric phase transition induced solely by increasing waiting time at certain temperatures (isothermal phase transition). Through cooling, a unique metastable state between a relaxor ferroelectric and a ferroelectric is unveiled, which in essence is initially a short-range ordered glassy state and then can evolve into a long-range ordered ferroelectric state through the isothermal process. It is also found that these isothermal ferroelectric transitions only occur within a specific temperature region with different waiting time needed. These features of isothermal phase transition can be understood by Landau theory analysis with the consideration of random defects as a competition between the thermodynamically favored long-range ordered state and the kinetically frustrated short-range ordered glassy state from random defects. This study offers a precise experimental as well as a phenomenological interpretation on the isothermal ferroelectric transition, which may help to further clarify the intricate structure-property relationship in this important lead-free piezoelectric material and other related systems.

Search for b->u Transitions inB- -> D0 K- and B- -> D*0 K-

Energy Technology Data Exchange (ETDEWEB)

Aubert, B.; Barate, R.; Boutigny, D.; Couderc, F.; Karyotakis, Y.; Lees, J.P.; Poireau, V.; Tisserand, V.; Zghiche, A.; /Annecy, LAPP; Grauges, E.; /Barcelona, IFAE; Palano, A.; Pappagallo, M.; Pompili, A.; /Bari U. /INFN, Bari; Chen, J.C.; Qi, N.D.; Rong, G.; Wang, P.; Zhu, Y.S.; /Beijing, Inst. High Energy Phys.; Eigen, G.; Ofte, I.; Stugu, B.

2005-05-27

The authors search for B{sup -} {yields} {tilde D}{sup 0}K{sup -} and B{sup -} {yields} {tilde D}*{sup 0}K{sup -}, with {tilde D}*{sup 0} {yields} {tilde D}{sup 0}{pi}{sup 0} or {tilde D}*{sup 0} {yields} {tilde D}{sup 0}{gamma}, and {tilde D}{sup 0} {yields} K{sup +}{pi}{sup -} (and charge conjugates). These final states can be reached through the b {yields} c transition B{sup -} {yields} D{sup (*)0}K{sup -} followed by the doubly CKM-suppressed D{sup 0} {yields} K{sup +}{pi}{sup -}, or the b {yields} u transition B{sup -} {yields} {bar D}{sup (*)0}K{sup -} followed by the CKM-favored {bar D}{sup 0} {yields} K{sup +}{pi}{sup -}. The interference of these two amplitudes is sensitive to the angle {gamma} of the unitarity triangle. The results are based on 232 million {Upsilon}(4S) {yields} B{bar B} decays collected with the BABAR detector at SLAC. They find no significant evidence for these decays. They set a limit r{sub B} {triple_bond} |A(B{sup -} {yields} {bar D}{sup 0}K{sup -})/A(B{sup -} {yields} D{sup 0}K{sup -})| < 0.23 at 90% C.L. using the most conservative assumptions on the values of the CKM angle {gamma} and the strong phases in the B and D decay amplitudes. In the case of the D* they set a 90% C.L. limit r*{sub B}{sup 2} {triple_bond} |A(B{sup -} {yields} {bar D}*{sup 0}K{sup -})/A(B{sup -} {yields} D*{sup 0} K{sup -})|{sup 2} < (0.16){sup 2} which is independent of assumptions on {gamma} and strong phases.

Neutron Diffraction Study On Gamma To Alpha Phase Transition In Ce0.9th0.1 Alloy

Energy Technology Data Exchange (ETDEWEB)

Lashley, Jason C1 [Los Alamos National Laboratory; Heffner, Robert H [Los Alamos National Laboratory; Llobet, A [Los Alamos National Laboratory; Darling, T W [U OF NEVADA; Jeong, I K [PUSAN NATL UNIV

2008-01-01

Comprehensive neutron diffraction measurements were performed to study the isostructural {gamma} {leftrightarrow} {alpha} phase transition in Ce{sub 0.9}Th{sub 0.1} alloy. Using Rietveld refinements, we obtained lattice and thermal parameters as a function of temperature. From the temperature slope of the thermal parameters, we determined Debye temperatures {Theta}{sup {gamma}}{sub D} = 133(1) K and {Theta}{sup {alpha}}{sub D} = 140(1) K for the {gamma} phase and the {alpha} phase, respectively. This result implies that the vibrational entropy change is not significant at the {gamma} {leftrightarrow} {alpha} transition, contrary to that from elemental Cerium [Phys. Rev. Lett. 92, 105702, 2004].

REVISITING ρ1 CANCRI e: A NEW MASS DETERMINATION OF THE TRANSITING SUPER-EARTH

International Nuclear Information System (INIS)

Endl, Michael; Cochran, William D.; MacQueen, Phillip J.; Barnes, Stuart I.; Robertson, Paul; Brugamyer, Erik J.; Caldwell, Caroline; Gullikson, Kevin; Wittenmyer, Robert A.

2012-01-01

We present a mass determination for the transiting super-Earth ρ 1 Cancri e based on nearly 700 precise radial velocity (RV) measurements. This extensive RV data set consists of data collected by the McDonald Observatory planet search and published data from Lick and Keck observatories. We obtained 212 RV measurements with the Tull Coudé Spectrograph at the Harlan J. Smith 2.7 m Telescope and combined them with a new Doppler reduction of the 131 spectra that we have taken in 2003-2004 with the High-Resolution Spectrograph (HRS) at the Hobby-Eberly Telescope for the original discovery of ρ 1 Cancri e. Using this large data set we obtain a five-planet Keplerian orbital solution for the system and measure an RV semi-amplitude of K = 6.29 ± 0.21 m s –1 for ρ 1 Cnc e and determine a mass of 8.37 ± 0.38 M ⊕ . The uncertainty in mass is thus less than 5%. This planet was previously found to transit its parent star, which allowed them to estimate its radius. Combined with the latest radius estimate from Gillon et al., we obtain a mean density of ρ = 4.50 ± 0.20 g cm –3 . The location of ρ 1 Cnc e in the mass-radius diagram suggests that the planet contains a significant amount of volatiles, possibly a water-rich envelope surrounding a rocky core.

E1-forbidden transition rates in ions of astrophysical interest

International Nuclear Information System (INIS)

Träbert, E

2014-01-01

Transition rates in atomic systems may appear to be of little importance in steady-state plasmas that are observed at great distances from Earth. However, some of the transition rates compete with collision rates, and in these cases certain line intensity ratios are affected and can serve as remote indicators of density. In the low-density environments of stellar coronae and planetary nebulae, the transition rates of interest are mostly spin-forbidden E1 decays, higher-multipole order transitions (M1, E2, M2, M3), and hyperfine-induced transitions. On Earth, measurements of the long upper level lifetimes of these atomic systems require the use of ion traps. A fair number of test cases with lifetimes in the range from nanoseconds to many seconds have been treated successfully, and the evolution of calculations along with the experimental progress is notable. A new generation of cold ion traps is expected to extend the atomic lifetime measurements on multiply charged ions into the range of many minutes. (paper)

Electrical properties and phase transition of Ba(Zr{sub 0.05}Ti{sub 0.95}){sub 1−x}(Fe{sub 0.5}Ta{sub 0.5}){sub x}O{sub 3} ceramics

Energy Technology Data Exchange (ETDEWEB)

Kruea-In, C. [Faculty of Science and Technology, Chiang Mai Rajabhat University (Thailand); Rujijanagul, G., E-mail: rujijanagul@yahoo.com [Department of Physics and Materials Science, Faculty of Science, Chiang Mai University (Thailand)

2015-09-15

Highlights: • Properties of of Ba(Zr{sub 0.05}Ti{sub 0.95}){sub 1−x}(Fe{sub 0.5}Ta{sub 0.5}){sub x}O{sub 3} ceramics were investigated. • Small amount of dopant produced a large change in dielectric and phase transition. • A phase diagram of Ba(Zr{sub 0.05}Ti{sub 0.95}){sub 1−x}(Fe{sub 0.5}Ta{sub 0.5}){sub x}O{sub 3} ceramics was proposed. • Dielectric tunability increased with increasing x concentration. - Abstract: In this work, properties of Ba(Zr{sub 0.05}Ti{sub 0.95}){sub 1−x}(Fe{sub 0.5}Ta{sub 0.5}){sub x}O{sub 3} ceramics with 0.00≤ x ≤0.07 were investigated. The ceramics were fabricated by a solid state reaction technique. X-ray diffraction analysis indicated that all samples exhibited single phase perovskite. Examination of the dielectric spectra revealed that the Fe and Ta additives promoted a diffuse phase transition, and the two phase transition temperatures, as observed in the dielectric curve of pure Ba(Zr{sub 0.05}Ti{sub 0.95})O{sub 3}, merged into a single phase transition temperature for higher x concentrations. The transformation was confirmed by ferroelectric measurements. In addition, the doped ceramics exhibited high relative dielectric tunability, especially for higher x concentration samples.

Abnormal magnetization and field-induced transition in (La0.73Bi0.27)0.67Ca0.33MnO3

International Nuclear Information System (INIS)

Li Haina; Wu Yuying; Yu Hongwei; Chen Ziyu; Huang Yan; Wang Shaoliang; Li Liang; Xia Zhengcai

2010-01-01

The magnetic field dependence of magnetization of Bi doped manganites (La 1-x Bi x ) 0.67 Ca 0.33 MnO 3 (x=0.27) was investigated at different temperatures with a pulsed high magnetic field. A metamagnetic transition was observed in the magnetization measurement, which revealed the coexistence of charge ordering (CO) and ferromagnetic (FM) phases. With decreasing magnetic field, the field-induced FM phases remained stable even when the magnetic field decreased to zero. This result suggests that ferromagnetic interactions are enhanced due to the effect of the pulsed high magnetic field, which makes the doped manganites a good system for magnetoresistance materials.

Efficacy and safety of fixed-combination travoprost 0.004%/timolol 0.5% in patients transitioning from bimatoprost 0.03%/timolol 0.5% combination therapy

Directory of Open Access Journals (Sweden)

Schnober D

2015-05-01

Full Text Available Dietmar Schnober,1 Douglas A Hubatsch,2 Maria-Luise Scherzer3 1Private Ophthalmology Practice, Werdohl, Germany; 2Alcon Laboratories, Inc., Fort Worth, TX, USA; 3Private Ophthalmology Practice, Regenstauf, Germany Purpose: To determine the efficacy and safety of fixed-combination travoprost 0.004%/timolol 0.5% preserved with polyquaternium-1 in patients with insufficient response to bimatoprost 0.03%/timolol 0.5% preserved with benzalkonium chloride.Patients and methods: In this open-label nonrandomized study conducted at 13 European sites, patients with primary open-angle glaucoma or ocular hypertension with insufficient intraocular pressure (IOP reduction during bimatoprost/timolol therapy were transitioned to travoprost/timolol (DuoTrav® administered every evening for 12 weeks. Change in IOP from baseline to week 12 was assessed in patients who transitioned from fixed-combination bimatoprost/timolol (n=57, primary endpoint. Secondary assessments included change in IOP at week 4, percentage of patients with IOP ≤18 mmHg at weeks 4 and 12, change in Ocular Surface Disease Index and ocular hyperemia scores at week 12, and patient preference. Adverse events were also reported.Results: IOP change (mean ± SD from baseline to week 12 was –3.8±1.9 mmHg (P<0.001; results were similar at week 4. Most patients had IOP ≤18 mmHg at weeks 4 and 12 (78.6% and 85.5%, respectively. Mean Ocular Surface Disease Index score was significantly reduced (P<0.001; no significant change in ocular hyperemia score was observed (P=0.197. Treatment-related adverse events included dysgeusia, nausea, paresthesia, myalgia, headache, and eye irritation (n=1 each. Most patients (74.5% preferred travoprost/timolol over bimatoprost/timolol.Conclusion: Transition to travoprost/timolol significantly reduced IOP and was well tolerated in patients who had elevated IOP despite bimatoprost/timolol therapy. Polyquaternium-1–preserved travoprost/timolol was preferred over

Observation of e(+)e(-) -> pi(0)pi(0)h(c) and a Neutral Charmoniumlike Structure Z(c)(0)

NARCIS (Netherlands)

Ablikim, M.; Achasov, M. N.; Ai, X. C.; Albayrak, O.; Albrecht, M.; Ambrose, D. J.; Amoroso, A.; An, F. F.; An, Q.; Bai, J. Z.; Ferroli, R. Baldini; Ban, Y.; Bennett, D. W.; Bennett, J. V.; Bertani, M.; Bettoni, D.; Bian, J. M.; Bianchi, F.; Boger, E.; Bondarenko, O.; Boyko, I.; Briere, R. A.; Cai, H.; Cai, X.; Cakir, O.; Calcaterra, A.; Cao, G. F.; Cetin, S. A.; Chang, J. F.; Chelkov, G.; Chen, G.; Chen, H. S.; Chen, H. Y.; Chen, J. C.; Chen, M. L.; Chen, S. J.; Chen, X.; Chen, X. R.; Chen, Y. B.; Cheng, H. P.; Chu, X. K.; Chu, Y. P.; Cibinetto, G.; Cronin-Hennessy, D.; Dai, H. L.; Dai, J. P.; Dedovich, D.; Deng, Z. Y.; Denig, A.; Denysenko, I.; Destefanis, M.; De Mori, F.; Ding, Y.; Dong, C.; Dong, J.; Dong, L. Y.; Dong, M. Y.; Du, S. X.; Duan, P. F.; Fan, J. Z.; Fang, J.; Fang, S. S.; Fang, X.; Fang, Y.; Fava, L.; Feldbauer, F.; Felici, G.; Feng, C. Q.; Fioravanti, E.; Fu, C. D.; Gao, Q.; Gao, Y.; Garzia, I.; Goetzen, K.; Gong, W. X.; Gradl, W.; Greco, M.; Gu, M. H.; Gu, Y. T.; Guan, Y. H.; Guo, A. Q.; Guo, L. B.; Guo, T.; Guo, Y.; Guo, Y. P.; Haddadi, Z.; Hafner, A.; Han, S.; Han, Y. L.; Harris, F. A.; He, K. L.; He, Z. Y.; Held, T.; Heng, Y. K.; Hou, Z. L.; Hu, C.; Hu, H. M.; Hu, J. F.; Hu, T.; Hu, Y.; Huang, G. M.; Huang, G. S.; Huang, H. P.; Huang, J. S.; Huang, X. T.; Huang, Y.; Hussain, T.; Ji, Q.; Ji, Q. P.; Ji, X. B.; Ji, X. L.; Jiang, L. L.; Jiang, L. W.; Jiang, X. S.; Jiao, J. B.; Jiao, Z.; Jin, D. P.; Jin, S.; Johansson, T.; Julin, A.; Kalantar-Nayestanaki, N.; Kang, X. L.; Kang, X. S.; Kavatsyuk, M.; Ke, B. C.; Kliemt, R.; Kloss, B.; Kolcu, O. B.; Kopf, B.; Kornicer, M.; Kuehn, W.; Kupsc, A.; Lai, W.; Lange, J. S.; Lara, M.; Larin, P.; Leyhe, M.; Li, Cheng; Li, D. M.; Li, F.; Li, G.; Li, H. B.; Li, J. C.; Li, Jin; Li, K.; Li, K.; Li, Q. J.; Li, T.; Li, W. D.; Li, W. G.; Li, X. L.; Li, X. M.; Li, X. N.; Li, X. Q.; Li, Z. B.; Liang, H.; Liang, Y. F.; Liang, Y. T.; Liao, G. R.; Lin, D. X.; Liu, B. J.; Liu, C. L.; Liu, C. X.; Liu, F. H.; Liu, Fang; Liu, Feng; Liu, H. B.; Liu, H. H.; Liu, H. H.; Liu, H. M.; Liu, J.; Liu, J. P.; Liu, J. Y.; Liu, K.; Liu, K. Y.; Liu, L. D.; Liu, Q.; Liu, S. B.; Liu, X.; Liu, X. X.; Liu, Y. B.; Liu, Z. A.; Liu, Zhiqiang; Liu, Zhiqing; Loehner, H.; Lou, X. C.; Lu, H. J.; Lu, J. G.; Lu, R. Q.; Lu, Y.; Lu, Y. P.; Luo, C. L.; Luo, M. X.; Luo, T.; Luo, X. L.; Lv, M.; Lyu, X. R.; Ma, F. C.; Ma, H. L.; Ma, Q. M.; Ma, S.; Ma, T.; Ma, X. N.; Ma, X. Y.; Maas, F. E.; Maggiora, M.; Malik, Q. A.; Mao, Y. J.; Mao, Z. P.; Marcello, S.; Messchendorp, J. G.; Min, J.; Min, T. J.; Mitchell, R. E.; Mo, X. H.; Mo, Y. J.; Moeini, H.; Morales Morales, C.; Moriya, K.; Muchnoi, N. Yu.; Muramatsu, H.; Nefedov, Y.; Nerling, F.; Nikolaev, I. B.; Ning, Z.; Nisar, S.; Niu, S. L.; Niu, X. Y.; Olsen, S. L.; Ouyang, Q.; Pacetti, S.; Patteri, P.; Pelizaeus, M.; Peng, H. P.; Peters, K.; Ping, J. L.; Ping, R. G.; Poling, R.; Pu, Y. N.; Qi, M.; Qian, S.; Qiao, C. F.; Qin, L. Q.; Qin, N.; Qin, X. S.; Qin, Y.; Qin, Z. H.; Qiu, J. F.; Rashid, K. H.; Redmer, C. F.; Ren, H. L.; Ripka, M.; Rong, G.; Ruan, X. D.; Santoro, V.; Sarantsev, A.; Savrie, M.; Schoenning, K.; Schumann, S.; Shan, W.; Shao, M.; Shen, C. P.; Shen, P. X.; Shen, X. Y.; Sheng, H. Y.; Shepherd, M. R.; Song, W. M.; Song, X. Y.; Sosio, S.; Spataro, S.; Spruck, B.; Sun, G. X.; Sun, J. F.; Sun, S. S.; Sun, Y. J.; Sun, Y. Z.; Sun, Z. J.; Sun, Z. T.; Tang, C. J.; Tang, X.; Tapan, I.; Thorndike, E. H.; Tiemens, M.; Toth, D.; Ullrich, M.; Uman, I.; Varner, G. S.; Wang, B.; Wang, B. L.; Wang, D.; Wang, D. Y.; Wang, K.; Wang, L. L.; Wang, L. S.; Wang, M.; Wang, P.; Wang, P. L.; Wang, Q. J.; Wang, S. G.; Wang, W.; Wang, X. F.; Wang, Y. D.; Wang, Y. F.; Wang, Y. Q.; Wang, Z.; Wang, Z. G.; Wang, Z. H.; Wang, Z. Y.; Wei, D. H.; Wei, J. B.; Weidenkaff, P.; Wen, S. P.; Wiedner, U.; Wolke, M.; Wu, L. H.; Wu, Z.; Xia, L. G.; Xia, Y.; Xiao, D.; Xiao, Z. J.; Xie, Y. G.; Xiu, Q. L.; Xu, G. F.; Xu, L.; Xu, Q. J.; Xu, Q. N.; Xu, X. P.; Xue, Z.; Yan, L.; Yan, W. B.; Yan, W. C.; Yan, Y. H.; Yang, H. X.; Yang, L.; Yang, Y.; Yang, Y. X.; Ye, H.; Ye, M.; Ye, M. H.; Yin, J. H.; Yu, B. X.; Yu, C. X.; Yu, H. W.; Yu, J. S.; Yuan, C. Z.; Yuan, W. L.; Yuan, Y.; Yuncu, A.; Zafar, A. A.; Zallo, A.; Zeng, Y.; Zhang, B. X.; Zhang, B. Y.; Zhang, C.; Zhang, C. C.; Zhang, D. H.; Zhang, H. H.; Zhang, H. T.; Zhang, H. Y.; Zhang, J. J.; Zhang, J. L.; Zhang, J. Q.; Zhang, J. W.; Zhang, J. Y.; Zhang, J. Z.; Zhang, K.; Zhang, L.; Zhang, S. H.; Zhang, X. J.; Zhang, X. Y.; Zhang, Y.; Zhang, Y. H.; Zhang, Z. H.; Zhang, Z. P.; Zhang, Z. Y.; Zhao, G.; Zhao, J. W.; Zhao, J. Y.; Zhao, J. Z.; Zhao, Lei; Zhao, Ling; Zhao, M. G.; Zhao, Q.; Zhao, Q. W.; Zhao, S. J.; Zhao, T. C.; Zhao, Y. B.; Zhao, Z. G.; Zhemchugov, A.; Zheng, B.; Zheng, J. P.; Zheng, Y. H.; Zhong, B.; Zhou, L.; Zhou, Li; Zhou, X.; Zhou, X. K.; Zhou, X. R.; Zhou, X. Y.; Zhu, K.; Zhu, K. J.; Zhu, S.; Zhu, X. L.; Zhu, Y. C.; Zhu, Y. S.; Zhu, Z. A.; Zhuang, J.; Zou, B. S.; Zou, J. H.

2014-01-01

Using data collected with the BESIII detector operating at the Beijing Electron Positron Collider at center-of-mass energies of root s = 4.23, 4.26, and 4.36 GeV, we observe e(+)e(-) -> pi(0)pi(0)h(c) for the first time. The Born cross sections are measured and found to be about half of those of

The E1 transitions in kaonic atoms

International Nuclear Information System (INIS)

Qureshi, I.E.

1984-01-01

The electric dipole transition rates in kanonic atoms are calculated by using distorted relativistic wave functions. The kaon-nucleus strong interaction which is responsible for the distortion of atomic states is considered to be proportional to the nuclear density and the effective isospin-averaged kaon-nucleon scattering length. Six atoms have been studied for which the last observed X-rays correspond to 3d-2p, 4f-3d, 5g-4f, 6h-5g, 7i-6h and 8j-7i transitions. It is found that the electric dipole transition rate is enhanced by an amount (0.3-7.6)x10 13 s -1 . (orig.)

On the high temperature phase transition in Ba(Zr0.20Ti0.80O3 ceramic

Directory of Open Access Journals (Sweden)

K. P. Chandra

2017-08-01

Full Text Available Temperature dependent X-ray diffraction (XRD and dielectric properties of perovskite Ba(Zr0.2Ti0.8O3 ceramic prepared using a standard solid-state reaction process is presented. Along with phase transitions at low temperature, a new phase transition at high temperature (873∘C at 20Hz, diffusive in character has been found where the lattice structure changes from monoclinic (space group: P2∕m to hexagonal (space group: P6∕mmm. This result places present ceramic in the list of potential candidate for intended high temperature applications. The AC conductivity data followed hopping type charge conduction and supports jump relaxation model. The experimental value of d33=98pC/N was found. The dependence of polarization and strain on electric field at room temperature suggested that lead-free Ba(Zr0.2Ti0.8O3 is a promising material for electrostrictive applications.

Selected properties of nuclei at the magic shell closures from the studies of E1, M1 and E2 transition rates

International Nuclear Information System (INIS)

Mach, H.; Baluyut, A.-M.; Smith, D.; Ruchowska, E.; Koester, U.; Fraile, L. M.; Penttilae, H.; Aeystoe, J.; Elomaa, V.-V.; Eronen, T.; Hakala, J.; Jokinen, A.; Karvonen, P.; Kessler, T.; Moore, I. D.; Rahaman, S.; Rissanen, J.; Ronkainen, J.; Ronkanen, P.; Saastamoinen, A.

2009-01-01

Using the Advanced Time-Delayed method we have studied transition rates in several neutron-rich nuclei at the magic shell closures. These include the heavy Co and Fe nuclei just below the Z = 28 shell closure at the point of transition from spherical to collective structures. Of particular interest is 63 Fe located exactly at the point of transition at N = 37. A substantial increase in the information on this nucleus was obtained from a brief fast timing study conducted at ISOLDE. The new results indicate that 63 Fe seems to depart from a simple shell model structure observed for heavier N = 37 isotones of 65 Ni and 67 Zn.Another region of interest are the heavy Cd and Sn nuclei at N = 72, 74 and the properties of negative parity quasi-particle excitations. These experiments, performed at the IGISOL separator at Jyvaeskylae, revealed interesting properties of the E2 rates in the sequence of E2 transitions connecting the 10 + , 8 + , 6 + , 4 + , 2 + and 0 + members of the multiplet of levels in 122 Sn due to neutrons in the h 11/2 orbit.

Full one-loop electroweak corrections to h0(H0,A0)H±W± associated productions at e+e- linear colliders

International Nuclear Information System (INIS)

Liu Jing; Ma Wengan; Zhang Renyu; Guo Lei; Jiang Yi; Han Liang

2007-01-01

We study the complete one-loop electroweak (EW) corrections to the processes of single charged Higgs boson production associated with a neutral Higgs boson (h 0 ,H 0 ,A 0 ) and a gauge boson W ± in the framework of the minimal supersymmetric standard model (MSSM). Numerical results at the SPS1a ' benchmark point as proposed in the SPA project, are presented for demonstration. We find that for the process e + e - →h 0 H ± W ± the EW relative correction can be either positive or negative and in the range of -15%∼20% in our chosen parameter space. While for the processes e + e - →H 0 (A 0 )H ± W ± the corrections generally reduce the Born cross sections and the EW relative corrections are typically of order -10%∼-20%

Ab initio computation of the transition temperature of the charge density wave transition in TiS e2

Science.gov (United States)

Duong, Dinh Loc; Burghard, Marko; Schön, J. Christian

2015-12-01

We present a density functional perturbation theory approach to estimate the transition temperature of the charge density wave transition of TiS e2 . The softening of the phonon mode at the L point where in TiS e2 a giant Kohn anomaly occurs, and the energy difference between the normal and distorted phase are analyzed. Both features are studied as functions of the electronic temperature, which corresponds to the Fermi-Dirac distribution smearing value in the calculation. The transition temperature is found to be 500 and 600 K by phonon and energy analysis, respectively, in reasonable agreement with the experimental value of 200 K.

Exciton luminescence in In0.3Ga0.7As/GaAs quantum well heterostructures

International Nuclear Information System (INIS)

Kapon, Eli; Mereuta, Alexandru; Dorogan, Andrei; Dragutan, Nicolae; Vieru, Tatiana; Syrbu, Nicolae

2011-01-01

Radiation maxima were observed in photoluminescence spectra of GaAs/ In 0.3 Ga 0.7 As/ GaAs in case of 632.8 nm and 532 nm He-Ne laser excitation conditioned by the recombination from ground (e1-hh1, e1-lh1) and excited (e2-hh2, e2-lh2) states of polarionic excitons in quantum wells. The doublet character of e1-hh1, e1-lh1 transitions can be explained by the interaction of excitons in quantum wells. Radiation maxima are revealed in the region of 1.5eV energy conditioned by recombination transitions E b -hh1, E b -lh1of the GaAs buffer layer.

Measurements of the absolute branching fractions for D→anti Kπe+νe, D→anti K*e+νe and determination of Γ(D+→anti K*0e+νe)/Γ(D+→anti K0e+νe)

International Nuclear Information System (INIS)

Ablikim, M.; Bai, J.Z.; Ban, Y.

2006-01-01

Using the data of about 33 pb -1 collected at and around 3.773 GeV with the BES-II detector at the BEPC collider, we have studied the exclusive semileptonic decays D + →K - π + e + ν e , D 0 →anti K 0 π - e + ν e , D + →anti K *0 e + ν e and D 0 →K *- e + ν e . The absolute branching fractions for the decays are measured to be BF(D + →K - π + e + ν e )=(3.50±0.75±0.27)%, BF(D 0 →anti K 0 π - e + ν e )=(2.61±1.04±0.28)%, BF(D + →anti K *0 e + ν e )=(5.06±1.21±0.40)% and BF(D 0 →K *- e + ν e )=(2.87±1.48±0.39)%. The ratio of the vector to pseudoscalar semileptonic decay rates Γ(D + →anti K *0 e + ν e )/Γ(D + →anti K 0 e + ν e ) is determined to be 0.57±0.17±0.02. (orig.)

PHYSICAL PROPERTIES OF THE 0.94-DAY PERIOD TRANSITING PLANETARY SYSTEM WASP-18

International Nuclear Information System (INIS)

Southworth, John; Anderson, D. R.; Maxted, P. F. L.; Hinse, T. C.; Dominik, M.; Mathiasen, M.; Browne, P.; Glitrup, M.; Joergensen, U. G.; Harpsoee, K.; Liebig, C.; Maier, G.; Bozza, V.; Calchi Novati, S.; Mancini, L.; Burgdorf, M.; Dreizler, S.; Hessman, F.; Hundertmark, M.; Finet, F.

2009-01-01

We present high-precision photometry of five consecutive transits of WASP-18, an extrasolar planetary system with one of the shortest orbital periods known. Through the use of telescope defocusing we achieve a photometric precision of 0.47-0.83 mmag per observation over complete transit events. The data are analyzed using the JKTEBOP code and three different sets of stellar evolutionary models. We find the mass and radius of the planet to be M b = 10.43 ± 0.30 ± 0.24 M Jup and R b = 1.165 ± 0.055 ± 0.014 R Jup (statistical and systematic errors), respectively. The systematic errors in the orbital separation and the stellar and planetary masses, arising from the use of theoretical predictions, are of a similar size to the statistical errors and set a limit on our understanding of the WASP-18 system. We point out that seven of the nine known massive transiting planets (M b > 3 M Jup ) have eccentric orbits, whereas significant orbital eccentricity has been detected for only four of the 46 less-massive planets. This may indicate that there are two different populations of transiting planets, but could also be explained by observational biases. Further radial velocity observations of low-mass planets will make it possible to choose between these two scenarios.

A comparative study of magnetic field induced meta-magnetic transition in nanocrystalline and bulk Pr{sub 0.65}(Ca{sub 0.7}Sr{sub 0.3}){sub 0.35}MnO{sub 3} compound

Energy Technology Data Exchange (ETDEWEB)

Saha, Suvayan [CMP Division, Saha Institute of Nuclear Physics, 1/AF, Bidhannagar, Kolkata 700 064 (India); Center for Research in Nanoscience and Nanotechnology, University of Calcutta, JD-2, Salt Lake City, Kolkata 700098, West Bengal (India); Department of Physics, University of Calcutta, 92 A.P.C. Road, Kolkata 700009 (India); Das, Kalipada, E-mail: kalipadadasphysics@gmail.com [Department of Materials Science, Indian Association for the Cultivation of Science, 2A and 2B Raja S.C. Mullick Road, Jadavpur, Kolkata 700032 (India); Bandyopadhyay, Sudipta [Center for Research in Nanoscience and Nanotechnology, University of Calcutta, JD-2, Salt Lake City, Kolkata 700098, West Bengal (India); Department of Physics, University of Calcutta, 92 A.P.C. Road, Kolkata 700009 (India); Das, I. [CMP Division, Saha Institute of Nuclear Physics, 1/AF, Bidhannagar, Kolkata 700 064 (India)

2017-06-15

Highlights: • Field induced sharp meta-magnetic transition appears even in nanocrystalline sample. • Magnetic field for the meta-magnetic transition enhances depending upon the cooling field. • This unusual behavior is addressed by the effect of the interfacial strains. - Abstract: In our present study we highlight the observations of external magnetic field induced sharp meta-magnetic transition in polycrystalline bulk as well as nanocrystalline form of Pr{sub 0.65}(Ca{sub 0.7}Sr{sub 0.7}){sub 0.35}MnO{sub 3} compound. Interestingly, such behavior persists in the nanoparticles regardless of the disorder broadened transition. However, higher magnetic field is required for nanoparticles having average particle size ∼40 nm for such meta-magnetic transition, which differs from the general trends of the pure charge ordered nano materials. The interfacial strain between the different magnetic domains plays the important role in magnetic isothermal properties of nanoparticles, when the samples are cooled down in different cooling field. Additionally, both the bulk and nanoparticle compounds exhibit spontaneous phase separation and significantly large magnetoresistance at the low temperature region due to the melting of charge ordered fraction.

Measurement of the absolute branching fraction of D-vertical bar -> (K)over-bar(0)e(vertical bar) nu(e) via (K)over-bar(0) -> pi(0)pi(0)

NARCIS (Netherlands)

Ablikim, M.; Achasov, N.; Ai, X. C.; Albayrak, O.; Albrecht, M.; Ambrose, D. J.; Amoroso, A.; An, F. F.; An, Q.; Bai, J. Z.; Ferroli, R. Baldini; Ban, Y.; Bennett, D. W.; Bennett, J. V.; Bertani, M.; Bettonin, D.; Bian, J. M.; Bianchi, F.; Boger, E.; Boyko, I.; Briere, R. A.; Cai, H.; Cai, X.; Cakir, O.; Caleaterra, A.; Cao, G. F.; Cetin, S. A.; Chang, J. F.; Chelkov, G.; Chen, G.; Chen, H. S.; Chen, H. Y.; Chen, J. C.; Chen, M. L.; Chen, S.; Chen, S. J.; Chen, X.; Chen, X. R.; Chen, Y. B.; Cheng, H. P.; Chu, X. K.; Cibinetto, G.; Dai, H. L.; Dai, J. P.; Dbeyssi, A.; Dedovich, D.; Deng, Z. Y.; Denig, A.; Denysenko, I.; Destefanis, M.; De Mori, F.; Ding, Y.; Dong, C.; Dong, J.; Dong, L. Y.; Dong, M. Y.; Dou, Z. L.; Du, S. X.; Duan, P. F.; Fan, J. Z.; Fang, J.; Fang, S. S.; Fang, X.; Fang, Y.; Farinelli, R.; Fava, L.; Fedorov, O.; Feldbauer, F.; Felici, G.; Feng, C. Q.; Fioravanti, E.; Fritsch, M.; Fu, C. D.; Gao, Q.; Gao, X. L.; Gao, X. Y.; Gao, Y.; Gao, Z.; Garzia, I.; Goetzen, K.; Gong, L.; Gong, W. X.; Gradl, W.; Greco, M.; Gu, M. H.; Gu, Y. T.; Guan, Y. H.; Guo, A. Q.; Guo, L. B.; Guo, R. P.; Guo, Y.; Guo, Y. P.; Haddadi, Z.; Hafner, A.; Han, S.; Hao, X. Q.; Harris, F. A.; He, K. L.; Held, T.; Heng, Y. K.; Hou, Z. L.; Hu, C.; Hu, H. M.; Hu, J. F.; Hu, T.; Hu, Y.; Huang, G. S.; Huang, J. S.; Huang, X. T.; Huang, X. Z.; Huang, Y.; Huang, Z. L.; Hussain, T.; Ji, Q.; Ji, Q. P.; Ji, X. B.; Ji, X. L.; Jiang, L. W.; Jiang, X. S.; Jiang, X. Y.; Jiao, J. B.; Jiao, Z.; Jin, D. P.; Jin, S.; Johansson, T.; Julin, A.; Kalantar-Nayestanaki, N.; Kang, X. L.; Kang, X. S.; Kavatsyuk, M.; Ke, B. C.; Kiese, P.; Kliemt, R.; Kloss, B.; Kolc, O. B.; Kopf, B.; Kornicer, M.; Kupse, A.; Kuehn, W.; Lange, J. S.; Lara, M.; Larin, P.; Leng, C.; Li, C.; Li, Cheng; Li, D. M.; Li, F.; Li, F. Y.; Li, G.; Li, H. B.; Li, H. J.; Li, J. C.; Li, Jin; Li, K.; Li, K.; Li, Lei; Li, P. R.; Li, Q. Y.; Li, T.; Li, W. D.; Li, W. G.; Li, X. L.; Li, X. N.; Li, X. Q.; Li, Y. B.; Li, Z. B.; Liang, H.; Liang, Y. F.; Liang, Y. T.; Liao, G. R.; Lin, D. X.; Liu, B.; Liu, B. J.; Liu, C. X.; Liu, D.; Liu, F. H.; Liu, Fang; Liu, Feng; Liu, H. B.; Liu, H. H.; Liu, H. H.; Liu, H. M.; Liu, J.; Liu, J. B.; Liu, J. P.; Liu, J. Y.; Liu, K.; Liu, K. Y.; Liu, L. D.; Liu, P. L.; Liu, Q.; Liu, S. B.; Liu, X.; Liu, Y. B.; Liu, Z. A.; Liu, Zhiqing; Loehner, H.; Lou, X. C.; Lu, H. J.; Lu, J. G.; Lu, Y.; Lu, Y. P.; Luo, C. L.; Luo, M. X.; Luo, T.; Luo, X. L.; Lu, X. R.; Ma, F. C.; Ma, H. L.; Ma, L. L.; Ma, M. M.; Ma, Q. M.; Ma, T.; Ma, X. N.; Ma, X. Y.; Ma, Y. M.; Maas, F. E.; Maggiora, M.; Mao, Y. J.; Mao, Z. P.; Marcello, S.; Messchendorp, J. G.; Min, J.; Min, T. J.; Mitchell, R. E.; Mo, X. H.; Mo, Y. J.; Morales, C. Morales; Muchnoi, N. Yu.; Muramatsu, H.; Nefedov, Y.; Nerling, F.; Nikolaev, I. B.; Ning, Z.; Nisar, S.; Niu, S. L.; Niu, X. Y.; Olsen, S. L.; Ouyang, Q.; Pacetti, S.; Pan, Y.; Patteri, P.; Pelizaeus, M.; Peng, H. P.; Peters, K.; Pettersson, J.; Ping, J. L.; Ping, R. G.; Poling, R.; Prasad, V.; Qi, H. R.; Qi, M.; Qian, S.; Qiao, C. F.; Qin, L. Q.; Qin, N.; Qin, X. S.; Qin, Z. H.; Qiu, J. F.; Rashid, K. H.; Redmer, C. F.; Ripka, M.; Rong, G.; Rosner, Ch.; Ruan, X. D.; Sarantsev, A.; Savrie, M.; Schoenning, K.; Schumann, S.; Shan, W.; Shao, M.; Shen, C. P.; Shen, P. X.; Shen, X. Y.; Sheng, H. Y.; Shi, M.; Song, W. M.; Song, X. Y.; Sosio, S.; Spataro, S.; Sun, G. X.; Sun, J. F.; Sun, S. S.; Sun, X. H.; Sun, Y. J.; Sun, Y. Z.; Sun, Z. J.; Sun, Z. T.; Tang, C. J.; Tang, X.; Tapan, I.; Thorndike, E. H.; Tiemens, M.; Ullrich, M.; Uman, I.; Varner, G. S.; Wang, B.; Wang, B. L.; Wang, D.; Wang, D. Y.; Wang, K.; Wang, L. L.; Wang, L. S.; Wang, M.; Wang, P.; Wang, P. L.; Wang, W.; Wang, W. P.; Wang, X. F.; Wang, Y.; Wang, Y. D.; Wang, Y. F.; Wang, Y. Q.; Wang, Z.; Wang, Z. G.; Wang, Z. H.; Wang, Z. Y.; Wang, Z. Y.; Weber, T.; Wei, D. H.; Weidenkaff, P.; Wen, S. P.; Wiedner, U.; Wolke, M.; Wu, L. H.; Wu, L. J.; Wu, Z.; Xia, L.; Xia, Y.; Xiao, D.; Xiao, H.; Xiao, Z. J.; Xie, Y. G.; Xiu, Q. L.; Xu, G. F.; Xu, J. J.; Xu, L.; Xu, Q. J.; Xu, Q. N.; Xu, X. P.; Yan, L.; Yan, W. B.; Yan, W. C.; Yan, Y. H.; Yang, H. J.; Yang, H. X.; Yang, L.; Yang, Y. X.; Ye, M.; Ye, M. H.; Yin, J. H.; Yu, B. X.; Yu, C. X.; Yu, J. S.; Yuan, C. Z.; Yuan, W. L.; Yuan, Y.; Yuncu, A.; Zafar, A. A.; Zallo, A.; Zeng, Y.; Zeng, Z.; Zhang, B. X.; Zhang, B. Y.; Zhang, C.; Zhang, C. C.; Zhang, D. H.; Zhang, H. H.; Zhang, H. Y.; Zhang, J.; Zhang, J. J.; Zhang, J. L.; Zhang, J. Q.; Zhang, J. W.; Zhang, J. Y.; Zhang, J. Z.; Zhang, K.; Zhang, L.; Zhang, S. Q.; Zhang, X. Y.; Zhang, Y.; Zhang, Y. H.; Zhang, Y. N.; Zhang, Y. T.; Zhang, Yu; Zhang, Z. H.; Zhang, Z. P.; Zhang, Z. Y.; Zhao, G.; Zhao, J. W.; Zhao, J. Y.; Zhao, J. Z.; Zhao, Lei; Zhao, Ling; Zhao, M. G.; Zhao, Q.; Zhao, Q. W.; Zhao, S. J.; Zhao, T. C.; Zhao, Y. B.; Zhao, Z. G.; Zhemchugov, A.; Zheng, B.; Zheng, J. P.; Zheng, W. J.; Zheng, Y. H.; Zhong, B.; Zhou, L.; Zhou, X.; Zhou, X. K.; Zhou, X. R.; Zhou, X. Y.; Zhu, K.; Zhu, K. J.; Zhu, S.; Zhu, S. H.; Zhu, X. L.; Zhu, Y. C.; Zhu, Y. S.; Zhu, Z. A.; Zhuangig, J.; Zotti, L.; Zou, B. S.; Zou, J. H.

2016-01-01

By analyzing 2.93 fb(-1) data collected at the center-of-mass energy root s = 3.773 GeV with the BESIII detector, we measure the absolute branching fraction of the semileptonic decay D+ -> (K) over bar (0)e(+)nu(e) to be B(D (+) -> (K) over bar (0)e(+)nu(e)) = (8.59 +/- 0.14 +/- 0.21)% using (K)

Electric Monopole Transition Strengths in the Stable Nickel Isotopes

Science.gov (United States)

Evitts, Lee John

A series of measurements of stable nickel isotopes were performed at the Australian National University in Canberra. Excited states in 58,60,62Ni were populated via inelastic scattering of proton beams delivered by the 14UD Pelletron accelerator. Multiple setups were used in order to determine the structure of low-lying states. The CAESAR array of Compton-suppressed HPGe detectors was used to measure the (E2/M1) mixing ratio of transitions from angular distributions of gamma rays. The Super-e spectrometer was used to measure conversion coefficients for a number of J to J transitions. The data obtained from both devices was combined with previously measured parent lifetimes and branching ratios to determine E0 transition strengths between J-pi transitions. The E0 transition strength for the second 0+ to first 0+ transitions in 60,62Ni have been measured for the first time through internal conversion electron detection. The experimental value of 132(+59,-70) for 62Ni agrees within 2 sigma of the previous result obtained from internal pair formation. However it is likely that the previous experimental results used an outdated theoretical model for internal pair formation emission. This work also represents the first measurements of E0 transition strengths between 2+ states in Ni isotopes. There is generally large E0 strength between the 2+ states, particularly in the second 2+ to first 2+ transition, however there is also a large uncertainty in the measurements owing to the difficulties involved in measuring conversion coefficients. In 62Ni, the E0 transition strength of 172(+62,-77) for the second 2+ to first 2+ transition gives further weight to the argument against the spherical vibrator model, as an E0 transition is forbidden if there is a change of only one phonon. The large measurement also indicates the presence of shape coexistence, complementing the recent experimental work carried out in the neutron-rich Ni isotopes.

Piezoelectric properties and diffusion phase transition around PPT of La-doped (Na{sub 0.52}K{sub 0.44}Li{sub 0.04}) Nb{sub 0.8}Ta{sub 0.2}O{sub 3} lead-free piezoelectric ceramics

Energy Technology Data Exchange (ETDEWEB)

Yang, Wenlong, E-mail: yangwenlong1983@163.com; Wang, Li; Li, Haidong; Han, Junsheng; Xiu, Hanjiang; Zhou, Zhongxiang

2016-10-01

Lead-free ceramics (Na{sub 0.52}K{sub 0.44}Li{sub 0.04}){sub 1−3x}La{sub x}Nb{sub 0.8}Ta{sub 0.2}O{sub 3} (KNLNT-Lax, x=0.00, 0.25, 0.5, 0.75, 1.00, 1.25 mol%) as non-polluting materials were prepared by solid state reaction method. The structure, piezoelectric proprieties and temperature stability of KNLNT ceramic with different La doping concentrations were investigated. The results show a transition from orthorhombic-tetragonal mix phase to tetragonal single phase with the variation of La{sup 3+} concentrations. The SEM micrographs of surface and fractured surface show a dense microstructure with few micropores. The La-doped KNLTN ceramic will be an alternative candidate contributes to excellent piezoelectric properties, which are found in the 0.75 mol% La-doped KNLNT ceramics, with d{sub 33}=215pC/N, k{sub p}=42.8%and Q{sub m}=89. It has been remarkably improved that the temperature stability of KNLTN-Lax piezoelectric properties at room temperature, and the dielectric relaxation can be observed obviously. The mechanism of La doping was analyzed in terms of valence compensation and polymorphic phase transition (PPT) diffusion. The orthorhombic-tetragonal phase transition around room temperature and the relaxation transition were considered contributing to the excellent piezoelectric performance and improved temperature stability of La{sup 3+}-doped KNLTN.

A Brillouin scattering study of La0.77Ca0.23MnO3 across the metal-insulator transition

International Nuclear Information System (INIS)

Seikh, Md Motin; Narayana, Chandrabhas; Sudheendra, L; Sood, A K; Rao, C N R

2004-01-01

Temperature-dependent Brillouin scattering studies have been carried out on La 0.77 Ca 0.23 MnO 3 across the paramagnetic insulator-ferromagnetic metal (I-M) transition (T C ∼ 230 K). The spectra show modes corresponding to a surface Rayleigh wave (SRW) and a high velocity pseudo-surface wave (HVPSAW) along with bulk acoustic waves (B1 and B2). The Brillouin shifts associated with the SRW and HVPSAW increase, whereas the B1 and B2 frequencies decrease, below T C . The temperature dependence of the SRW and HVPSAW modes is related to the increase in the elastic constant C 11 across the I-M transition. The decrease in frequency across the I-M transition of the bulk modes is understood to be due to enhanced self-energy corrections as a result of increased magnon-phonon interaction across the I-M transition. Correspondingly, these modes show a large increase in the full width at half maximum (FWHM) as the temperature decreases. We also observe a central peak whose width is maximum at T C

Pressure Effects on the Magnetic Phase Transition of Mn3SnC1−xNx (x = 0, 0.5)

International Nuclear Information System (INIS)

Hu Jing-Yu; Zhao Qing; Wen Yong-Chun; Wang Cong; Yao Yuan; Jin Chang-Qing; Yu Ri-Cheng

2012-01-01

The electronic transport properties of Mn 3 SnC and Mn 3 SnC 0.5 N 0.5 were measured under pressures up to 1.8 GPa. At ambient pressure, an abrupt increase of resistance occurs around the temperature of magnetic phase transition in both samples. The transition temperature Tc from paramagnetic to ferrimagnetic state decreases linearly at rates of 12.6 and 6.3K/GPa with pressure for Mn 3 SnC and Mn 3 SnC 0.5 N 0.5 , respectively. This phenomenon could be understood by the Labbe-Jardin tight binding approximation model. (condensed matter: structure, mechanical and thermal properties)

The off-shell axial anomaly via the γ*π0→γ transition

International Nuclear Information System (INIS)

Roberts, C.D.; Frank, M.R.; Mitchell, K.L.; Tandy, P.C.

1995-01-01

The γ*π 0 → γ form factor, F π0γγ (s), including the extension off the pion mass-shell, is calculated in generalized impulse approximation within the Dyson-Schwinger Equation framework used to provide an excellent description of the pion charge form factor, described above. This anomalous process is a fundamentally important characteristic of the quantum field theoretical structure of QCD because it signals the breaking of the U A (1) symmetry by quantization. This form factor was measured by the CELLO collaboration at the PETRA storage ring using the process e + e - → e + e - π 0 . There is a letter-of-intent at CEBAF to remeasure this form factor in virtual Compton scattering from a proton target. In this case a (virtual) pion is supplied by the target and a final real photon selected through the excellent missing mass spectrometry available at CEBAF. An extrapolation to the pion mass shell will be needed to deduce the physical transition form factor. Our calculation shows that the dependence on the virtual-pion momentum is smooth and well described by a simple suppression factor, which is qualitatively independent of the details of the pion interpolating field. The correct mass-shell value of this form factor is naturally generated in our approach and the q 2 dependence is in accord with the available CELLO data. No parameters are adjusted to achieve this; the are fixed at the values derived in the study of F π (q 2 ). A significant result of our study is that for this anomalous process, soft nonperturbative effects remain significant for Q 2 2 . A paper describing this work was submitted for publication

QCD jets in e+e--annihilation and the transition into hadrons

International Nuclear Information System (INIS)

Ritter, S.

1982-03-01

A model has been developed describing QCD jets in the leading logarithmic approximation (LLA) and the subsequent transition into hadrons via a chain decay model. Besides of the production of mesons, the model is also able to describe baryon production. Agreement with recent data from e + e - -annihilation is found. This includes average multiplicities, average transverse momenta and transverse momentum distributions, longitudinal momentum distributions as well as particle production ratios π +- :K +- :p(antip), charge compensation probabilities and energy flux correlations. The model is compared to similar models developed by other authors. (author)

E-Learning 2.0: Learning Redefined

OpenAIRE

Kumar, Rupesh

2009-01-01

The conventional e-learning approach emphasizes a learning system more than a learning environment. While traditional e-learning systems continue to be significant, there is a new set of services emerging, embracing the philosophy of Web 2.0. Known as e-learning 2.0, it aims to create a personalized learning environment. E-learning 2.0 combines the use of discrete but complementary tools and web services to support the creation of ad-hoc learning communities. This paper discusses the influenc...

The (e,eprimep0) coincidence cross section for 12C at transfer energy of 40 MeV

International Nuclear Information System (INIS)

Tadokoro, T.; Hotta, T.; Miura, T.; Sugawara, M.; Takahashi, A.; Tamae, T.; Tanaka, E.; Miyase, H.; Tsubota, H.

1994-01-01

The energy spectra and angular distributions of protons from the 12 C(e,e primep ) coincidence reaction have been measured at azimuthal angles of φ p =-45 circle and -135 circle out of the scattering plane, at energy transfer of 40 MeV and momentum transfer of 0.35 fm -1 (69 MeV/c). The longitudinal-transverse interference term, as well as the non-interference term of the (e,e primep 0 ) cross section have been obtained, and the transition amplitudes are deduced in the LS coupling basis. The cross sections are compared with an RPA calculation. The photo-reaction cross section derived from the transverse term is in reasonable agreement with previous experimental results. ((orig.))

Electric Monopole Transition Strengths in 62Ni

Directory of Open Access Journals (Sweden)

Evitts L. J.

2016-01-01

Full Text Available Excited states in 62Ni were populated with a (p, p’ reaction using the 14UD Pelletron accelerator at the Australian National University. Electric monopole transition strengths, ρ2(E0, were measured through simultaneous detection of the internal conversion electrons and γ rays emitted from the de-excitation of populated states, using the Super-e spectrometer coupled with a germanium detector. The strength of the 02+ to 01+ transition has been measured to be 77−34+23 × 10−3 and agrees with previously reported values. Upper limits have been placed on the 03+ to 01+ and 03+ to 02+ transitions. The measured ρ2(E0 value of the 22+ to 21+ transition in 62Ni has been measured for the first time and found to be one of the largest ρ2(E0 values measured to date in nuclei heavier than Ca. The low-lying states of 62Ni have previously been classified as one- and two-phonon vibrational states based on level energies. The measured electric quadrupole transition strengths are consistent with this interpretation. However as electric monopole transitions are forbidden between states which differ by one phonon number, the simple harmonic quadrupole vibrational picture is not suffcient to explain the large ρ2(E0 value for the 22+ to 21+ transition.

Electric Monopole Transition Strengths in 62Ni

Science.gov (United States)

Evitts, L. J.; Garnsworthy, A. B.; Kibédi, T.; Moukaddam, M.; Alshahrani, B.; Eriksen, T. K.; Holt, J. D.; Hota, S. S.; Lane, G. J.; Lee, B. Q.; McCormick, B. P.; Palalani, N.; Reed, M. W.; Stroberg, S. R.; Stuchbery, A. E.

2016-09-01

Excited states in 62Ni were populated with a (p, p') reaction using the 14UD Pelletron accelerator at the Australian National University. Electric monopole transition strengths, ρ2(E0), were measured through simultaneous detection of the internal conversion electrons and γ rays emitted from the de-excitation of populated states, using the Super-e spectrometer coupled with a germanium detector. The strength of the 02+ to 01+ transition has been measured to be 77-34+23 × 10-3 and agrees with previously reported values. Upper limits have been placed on the 03+ to 01+ and 03+ to 02+ transitions. The measured ρ2(E0) value of the 22+ to 21+ transition in 62Ni has been measured for the first time and found to be one of the largest ρ2(E0) values measured to date in nuclei heavier than Ca. The low-lying states of 62Ni have previously been classified as one- and two-phonon vibrational states based on level energies. The measured electric quadrupole transition strengths are consistent with this interpretation. However as electric monopole transitions are forbidden between states which differ by one phonon number, the simple harmonic quadrupole vibrational picture is not suffcient to explain the large ρ2(E0) value for the 22+ to 21+ transition.

The Phase Transitions between H 0.27V 0.27W 0.73O 3· {1}/{3} H 2O and V 0.27W 0.73O 2.865: An X-Ray, Thermal Analysis, and HREM Study

Science.gov (United States)

Dupont, L.; Sundberg, M.

1998-03-01

A mixed vanadium-tungsten oxide hydrate (H 0.27V 0.27W 0.73O 3· {1}/{3}H 2O) has been synthesized by a soft chemistry method, and the phase transitions from the hydrate (precursor) to the final product V 0.27W 0.73O 2.865have been studied by thermal analysis, X-ray powder diffraction, and high-resolution electron microscopy (HREM) techniques. Supermetastable, metastable, and stable oxides have been observed. H 0.27V 0.27W 0.73O 3· {1}/{3}H 2O possesses a structure related to WO 3· {1}/{3}H 2O. Dehydration of the precursor leads to a supermetastable phase, H 0.27V 0.27W 0.73O 3, with a structure similar to that of the hydrate. At 350°C this phase transforms to the metastable H 0.27V 0.27W 0.73O 3, with a structure isotypic with WO 3(hex). The phase transition between the hydrate and H 0.27V 0.27W 0.73O 3is both pseudomorphous and topotactic. Removal of hydrogen and oxygen from the metastable oxide induces a second phase transition at 500°C to a more stable phase, V 0.27W 0.73O 2.865, with an oxygen-deficient WO 3-type structure. The monoclinic symmetry of the latter oxide increases at higher temperature, first to orthorhombic and then to tetragonal. This transition is not pseudomorphous but of a topotactic nature. The obtained results suggest that the hydrogen content stabilizes the WO 3(hex)-related structure of the metastable phase. A hypothetical model based on HREM observations is proposed for the structural transformation H 0.27V 0.27W 0.73O 3→V 0.27W 0.73O 2.865.

Measurement of the branching ratios of the decays Ξ0→Σ+e-νbare and Ξ-bar0->Σ-bar+e+νe

International Nuclear Information System (INIS)

Batley, J.R.; Kalmus, G.E.; Lazzeroni, C.

2007-01-01

From 56 days of data taking in 2002, the NA48/1 experiment observed 6316 Ξ 0 ->Σ + e - ν-bar e candidates (with the subsequent Σ + →pπ 0 decay) and 555 Ξ-bar 0 →Σ-bar + e + ν e candidates with background contamination of 215±44 and 136±8 events, respectively. From these samples, the branching ratios BR(Ξ 0 →Σ + e - ν-bar e )=(2.51±0.03 stat ±0.09 syst )x10 -4 and BR(Ξ-bar 0 →Σ-bar + e + ν e )=(2.55±0.14 stat ±0.10 syst )x10 -4 were measured allowing the determination of the CKM matrix element vertical bar V us vertical bar =0.209 -0.028 +0.023 . Using the Particle Data Group average for vertical bar V us vertical bar obtained in semileptonic kaon decays, we measured the ratio g 1 /f 1 =1.20±0.05 of the axial-vector to vector form factors.

M1 and E2 transitions in the ground-state configuration of atomic ...

Indian Academy of Sciences (India)

have calculated the forbidden transition (M1 and E2) parameters such as transition energies, log- arithmic weighted ... Keywords. Forbidden transitions; transition energies; logarithmic weighted oscillator strengths; .... optimizing the energy function based on the non-relativistic Hamiltonian of an atom,. HNR = N. ∑ j=1. (12∇ ...

Interband transitions in 106Pd, 152Sm, 152Gd and 182W

International Nuclear Information System (INIS)

Kartashov, V.M.; Oborovskij, A.I.; Troitskaya, A.G.

1990-01-01

Internal transitions in 106 Pd, 152 Sm, 152 Gd, 182 W nuclei, observed during decay of 152,152m Eu, 182,183 Ta, 106m Ag, are studied. The experimental characteristics of E0-transitions and E0-components of E0+M1+E2 type transitions in the studied nuclei, relative intensities of internal conversion electron lines during 182 Ta decay, multipolar composition and forbidden factor for 182 W and 183 W low-energy transitions, characteristics of transitions are presented

Δ(1232) production via charge-changing weak currents: e-+p→Δ0+ν/sub e/ and e++p→Δ/sup ++/+nu-bar/sub e/

International Nuclear Information System (INIS)

Hwang, W.P.; Henley, E.M.; Kisslinger, L.S.

1987-01-01

We investigate Δ(1232) production via charge-changing weak currents e - +p→Δ 0 +ν/sub e/ and e + +p→Δ/sup ++/+nu-bar/sub e/ at electron/positron beam energies in the range of a few GeV. A general formalism is introduced for the N→Δ transition form factors, including the weak magnetism, weak quadrupole, and weak scalar form factors for the polar-vector current and the axial, pseudoscalar, recoil, and weak electric form factors for the axial current. The form factors related to the polar-vector current are related to Δ(1232) electroproduction on a nucleon target. For nucleons and deltas, we adopt in this calculation the flavor SU(6) wave functions, with quarks described as confined Dirac particles. The quark wave function adopted is of the form given by the MIT bag model, with or without the sharp boundary smoothened out. In the few GeV range, it is found that cross sections can be as large as 10/sup -38/ cm 2 and are sensitive to induced form factors such as the weak magnetism form factor. It is also found that, for a beam energy of around 4.0 GeV, the predicted cross sections depend sensitively on whether or not the sharp boundary in the quark wave function is smoothened out

Tuning the magnetic phase transition and the magnetocaloric properties of La0.7Ca0.3MnO3 compounds through Sm-doping

Science.gov (United States)

Thanh, Tran Dang; Dung, Nguyen Thi; Van Dang, Nguyen; Bau, Le Viet; Piao, Hong-Guang; Phan, The Long; Huyen Yen, Pham Duc; Hau, Kieu Xuan; Kim, Dong-Hyun; Yu, Seong-Cho

2018-05-01

In this work, we point out that the width and the nature of the magnetic phase transition, TC value, and as well as magnetocaloric effect in La0.7-xSmxCa0.3MnO3 compounds can be easily modified through Sm-doped into La-site. With an increasing Sm concentration, a systematic decrease in the magnetization, TC, and magnetic entropy change (ΔSm) are observed. The Arrott-plot proveds that the samples with x = 0 and 0.1 undergoing a first-order phase transition. Meanwhile, sample x = 0.2 undergoes a second-order phase transition, which exhibits a high value of the relative cooling power (81.5 J/kg at ΔH = 10 kOe). An analysis of the critical behavior based on the modified Arrott plots method has been done for sample x = 0.2. The results proved a coexistence of the long- and short-range interactions in La0.5Sm0.2Ca0.3MnO3 compound.

Nanosize effects on the magnetic field induced transitions in La0.67−xEuxCa0.33MnO3 perovskite manganite

International Nuclear Information System (INIS)

Raju, N.; Roja Sree, D.; Reddy, S. Shravan Kumar; Reddy, Ch. Gopal; Reddy, P. Yadagiri; Reddy, K. Rama; Reddy, V. Raghavendra; Reddy Turpu, Goverdhan

2014-01-01

The nanosize effects on magnetic field induced transitions in La 0.67−x Eu x Ca 0.33 MnO 3 (x=0.25 and 0.27) system are presented in this paper. The reduction in the particle size of the system shows drastic effects on the electrical transport properties leading to robustness of the charge ordering phenomenon. The metal–insulator transition found in bulk materials at low magnetic fields disappeared in nanoparticles of the same material and a high field induced metal–insulator transition emerged at lower temperatures. These results manifest a strong correlation between the chemical pressures induced by doping of various ions at A-site and nanosize related phenomenon. - Highlights: • Chemical pressure and nanosize effects on electrical transport studies of Eu doped LCMO system are reported. • Decrease in particle size resulted in drastic changes on electrical transport studies. • Metal–insulator transition found in bulk at low magnetic fields disappeared in nanoparticles

Birefringence imaging of phase transitions: application to Na0.5Bi0.5TiO3

International Nuclear Information System (INIS)

Geday, M.; Kreisel, J.; Glazer, A.M.; Roleder, K.

2000-01-01

In recent years a number of imaging techniques to determine the optical properties of materials, either in reflection or in transmission, have been developed. Here the use of an imaging version of the so-called rotating-polarizer method in the study of phase transformations in crystals is demonstrated. This method creates false-coloured images representing the light transmission I 0 , the extinction angle φ (orientation of the optical indicatrix) and vertical stroke sin δ vertical stroke, a function of the retardation resulting from the birefringence (and a measure of the magnitude of optical anisotropy). When combined with a computer-controlled heating stage, this method provides an opportunity to create separate moving images of orientation and magnitude of optical anisotropy, showing the dynamics of twinning and domain-wall behaviour during temperature changes. It is believed that this is the first time that quantitative imaging of changes in birefringence has been used in this way to describe phase transitions. Two-phase transitions in a crystal of Na 0.5 Bi 0.5 TiO 3 (NBT) are presented as examples of the use of the system. (orig.)

Magnetic moments, E3 transitions and the structure of high spin core excited states in 211Rn

International Nuclear Information System (INIS)

Poletti, A.R.; Dracoulis, G.D.; Byrne, A.P.; Stuchbery, A.E.; Poletti, S.J.; Gerl, J.; Lewis, P.M.

1985-03-01

The results of g-factor measurements of high spin states in 211 Rn are: Esub(x)=8856+Δsup(') keV (Jsup(π)=63/2 - ), g=0.626(7); 6101+Δsup(') keV (49/2 + ), 0.766(8); 5247+Δsup(') keV (43/2 - ), 0.74(2); 3927+Δsup(') keV (35/2 + ), 1/017(12); 1578+Δsup(') keV (17/2 - ), 0.912(9). These results together with measured E3 transition strengths and shell model calculations are used to assign configurations to the core excited states in 211 Rn. Mixed configurations are required to explain the g-factors and enhanced E3 strengths simultaneously

Magnetic moments, E3 transitions and the structure of high-spin core excited states in 211Rn

International Nuclear Information System (INIS)

Poletti, A.R.; Dracoulis, G.D.; Byrne, A.P.; Stuchbery, A.E.; Poletti, S.J.; Gerl, J.; Lewis, P.M.

1985-01-01

The results of g-factor measurements of high-spin states in 211 Rn are: Esub(x)=8856+Δ' keV (Jsup(π)=63/2 - ), g=0.626(7); 6101+Δ' keV (49/2 + ), 0.766(8); 5347+Δ' keV (43/2 - ), 0.74(2); 3927+Δ keV (35/2 + ), 1.017(12); 1578+Δ keV (17/2 - ), 0.912(9). These results together with measured E3 transition strengths and shell model calculations are used to assign configurations to the core excited states in 211 Rn. Mixed configurations are required to explain the g-factors and enhanced E3 strengths simultaneously. (orig.)

Search for the Lepton-Flavor-Violating Decays B-s(0) -> e(+/-)mu(-/+) and B-0 -> e(+/-)mu(-/+)

NARCIS (Netherlands)

Aaij, R.; Adeva, B.; Adinolfi, M.; Adrover, C.; Affolder, A.; Ajaltouni, Z.; Albrecht, J.; Alessio, F.; Alexander, M.; Ali, S.; Alkhazov, G.; Cartelle, P. Alvarez; Alves, A. A.; Amato, S.; Amerio, S.; Amhis, Y.; Anderlini, L.; Andreassen, R.; Andrews, J. E.; Appleby, R. B.; Gutierrez, O. Aquines; Archilli, F.; Artamonov, A.; Artuso, M.; Aslanides, E.; Auriemma, G.; Baalouch, M.; Bachmann, S.; Back, J. J.; Baesso, C.; Balagura, V.; Baldini, W.; Barlow, R. J.; Barschel, C.; Barsuk, S.; Barter, W.; Bauer, Th; Beddow, J.; Bedeschi, F.; Bediaga, I.; Belogurov, S.; Belous, K.; Belyaev, I.; Ben-Haim, E.; Bencivenni, G.; Benson, S.; Benton, J.; Berezhnoy, A.; Pellegrino, A.; Tolk, S.

2013-01-01

A search for the lepton-flavor-violating decays B-s(0) -> e(+/-)mu(-/+) and B-0 -> e(+/-)mu(-/+) is performed with a data sample, corresponding to an integrated luminosity of 1.0 fb(-1) of pp collisions at root s = 7 TeV, collected by the LHCb experiment. The observed number of B-s(0) ->

0 - π Quantum transition in a carbon nanotube Josephson junction: Universal phase dependence and orbital degeneracy

Science.gov (United States)

Delagrange, R.; Weil, R.; Kasumov, A.; Ferrier, M.; Bouchiat, H.; Deblock, R.

2018-05-01

In a quantum dot hybrid superconducting junction, the behavior of the supercurrent is dominated by Coulomb blockade physics, which determines the magnetic state of the dot. In particular, in a single level quantum dot singly occupied, the sign of the supercurrent can be reversed, giving rise to a π-junction. This 0 - π transition, corresponding to a singlet-doublet transition, is then driven by the gate voltage or by the superconducting phase in the case of strong competition between the superconducting proximity effect and Kondo correlations. In a two-level quantum dot, such as a clean carbon nanotube, 0- π transitions exist as well but, because more cotunneling processes are allowed, are not necessarily associated to a magnetic state transition of the dot. In this proceeding, after a review of 0- π transitions in Josephson junctions, we present measurements of current-phase relation in a clean carbon nanotube quantum dot, in the single and two-level regimes. In the single level regime, close to orbital degeneracy and in a regime of strong competition between local electronic correlations and superconducting proximity effect, we find that the phase diagram of the phase-dependent transition is a universal characteristic of a discontinuous level-crossing quantum transition at zero temperature. In the case where the two levels are involved, the nanotube Josephson current exhibits a continuous 0 - π transition, independent of the superconducting phase, revealing a different physical mechanism of the transition.

Frequency-modulation transient absorption spectrum of the HCCl A 1A double-prime(0,0,0)left-arrow X 1A'(0,0,0) transition

International Nuclear Information System (INIS)

Chang, B.; Sears, T.J.

1995-01-01

The rotationally resolved spectrum of the HCCl A 1 A double-prime(0,0,0)left-arrow X 1 A'(0,0,0) transition between 12 230 and 12 410 cm -1 was obtained for the first time at Doppler-limited resolution using a frequency-modulation (FM) transient absorption technique. Five major subbands (K a =0 left-arrow 1, 1 left-arrow 0, 1 left-arrow 2, 2 left-arrow 1, and 2 left-arrow 3) of HC 35 Cl and one subband (K a =0 left-arrow 1) of HC 37 Cl were observed and assigned. In addition, the forbidden subband (K a =0 left-arrow 0) of HC 35 Cl was also observed. Thus far, we have assigned most (more than 70%) of the strong lines. The analysis of these subbands determines the geometry for the HCCl A(0,0,0) level: angle HCCl=134.7 degree and R C-Cl =1.623 A while R C-H is fixed at the corresponding value of CH 2 . The height of the barrier to linearity was found to be approximately 2170 cm -1 above the vibrationless level of the A state. The rotational structure of this spectrum shows irregular perturbations. Both random and J-dependent (anomalous K-type doubling) effects were observed. As in methylene, the perturbations most likely arise from Renner--Teller effect between the two singlet states in combination with spin--orbit coupling between the singlet and triplet states

Study of the B"0 → K"*"0e"+e"- decay with the LHCb detector and development of a novel concept of PID detector: the Focusing DIRC

International Nuclear Information System (INIS)

Borsato, M.

2015-01-01

Flavour-changing neutral current processes of the type b → sγ are forbidden at the tree level in the Standard Model (SM) and occur at leading order through radiative loop diagrams. Therefore, they are sensitive to new physics (NP), which may contribute with competing diagrams. Furthermore, the chirality of the weak interaction in the SM implies that the photon emitted has left-handed polarisation. However, a whole class of NP theories do not share this SM feature and may manifest unambiguously as a right-handed contribution to the polarisation. This thesis presents the first study of the b → sγ photon polarisation through an angular analysis of the B"0 → K"*"0e"+e"- channel. Even though B"0 → K"*"0e"+e"- is not a radiative b → s transition, the contribution from a virtual photon coupling to the lepton pair dominates in the low-q"2 region. Furthermore, the channel with electrons rather than muons allows to better isolate the virtual photon contribution at the low end of the q"2 spectrum. The integrated luminosity of 3 fb"-"1 collected by LHCb during LHC Run 1 allowed for the first time to select a sample of B"0 → K"*"0e"+e"- events large enough to measure the transverse asymmetries A_T"("2") = -0.23±0.23±0.05 and A_T"l"m = 0.14±0.22±0.05 in the low q"2 region between 0.002 GeV"2/c"4 and 1 GeV"2/c"4. These measurements are found to be consistent with SM predictions and provide new constraints on right handed contributions to the photon polarisation at the same level of precision as the one from the average of measurements involving radiative decays made at B-factories. Flavour physics experiments require advanced detectors dedicated to the identification of the different flavours of charged hadrons. Most of them are based on the detection of the Cherenkov light emitted by these particles as they traverse a dielectric medium. This thesis presents also a research/development activity on a new detector concept based on the BABAR DIRC, the FDIRC. Its

The electric monopole transition: Nuclear structure, and nuclear spectroscopy

International Nuclear Information System (INIS)

Zganiar, E.F.

1992-01-01

The electric monopole (E0) transition process provides unique information on the structure of nuclei. For example, δI=0 transitions between nuclear configurations of different shape have enhanced EO components. The authors have observed I π→Iπ (I=0) transitions in 185 Pt and 184 Pt which are pure E0. This is unprecedented. Further, they have initiated searches for the location of the superdeformed band in 192 Hg utilizing internal conversion spectroscopy and, for the first time, internal pair spectroscopy. Additionally, the lifetime of the 0 + 2 level in 188 Hg was measured with a newly developed picosecond lifetime system which utilized the 0 + 2 →0 + 1 E0 internal conversion transition as an energy gate and its associated atomic X-ray as a fast trigger. The role of the E0 internal conversion process in the study of nuclear structure and as a tool in nuclear spectroscopy are discussed

Optical transition radiation interferometry for A0 photoinjector

International Nuclear Information System (INIS)

Kazakevich, G.; Novosibirsk, IYF; Edwards, H.; Fliller, R.; Lebedev, V.; Nagaitsev, S.; Santucci, J.; Thurman-Keup, R.; Fermilab; Piot, P.; Fermilab; Northern Illinois U.; Li, J.; Tikhoplav, R.; UCLA

2007-01-01

A charged particle passing through the boundary of two medias with different permittivity values generates Transition Radiation (TR), [1]. The TR is caused by a variation of the particle electric field with variation of the permittivity. The TR for relativistic particles has a wide spectrum with a significant portion in the optical range. The Optical Transition Radiation (OTR) is widely used for a beam profile monitoring and measurements of a beam size. Moreover, OTR can be used to characterize the energy, energy spread and transverse angles in the beam by employing the interference of the OTR from two thin films [2] inserted in the beam trajectory. This method has been applied in number of works [3-5] demonstrating high results and good coincidence in measurements and calculations. In this paper we present and discuss in details a simulation of the interference pattern in several experimental setups. We consider the main optical effects, for diagnostics for the beam properties at A0 Photoinjector and the ILC module test area (NML) in a wide range of electron beam energy. In this paper, we first derive the OTR intensity formula for a single film at 90 degrees to the beam, then for two films at normal incidence, and finally with films at 45 degree incidence to the beam. The last section illustrates application with beam parameters like those at the A0 Photoinjector (electron energy 15 MeV)

Measurement of the absolute branching fraction of D+ → K̅0 e+νe via K̅0 → π 0 π 0

Science.gov (United States)

Ablikim, M.; Achasov, M. N.; Ai, X. C.; Albayrak, O.; Albrecht, M.; Ambrose, D. J.; Amoroso, A.; An, F. F.; An, Q.; Bai, J. Z.; Baldini Ferroli, R.; Ban, Y.; Bennett, D. W.; Bennett, J. V.; Bertani, M.; Bettoni, D.; Bian, J. M.; Bianchi, F.; Boger, E.; Boyko, I.; Briere, R. A.; Cai, H.; Cai, X.; Cakir, O.; Calcaterra, A.; Cao, G. F.; Cetin, S. A.; Chang, J. F.; Chelkov, G.; Chen, G.; Chen, H. S.; Chen, H. Y.; Chen, J. C.; Chen, M. L.; Chen, S.; Chen, S. J.; Chen, X.; Chen, X. R.; Chen, Y. B.; Cheng, H. P.; Chu, X. K.; Cibinetto, G.; Dai, H. L.; Dai, J. P.; Dbeyssi, A.; Dedovich, D.; Deng, Z. Y.; Denig, A.; Denysenko, I.; Destefanis, M.; De Mori, F.; Ding, Y.; Dong, C.; Dong, J.; Dong, L. Y.; Dong, M. Y.; Dou, Z. L.; Du, S. X.; Duan, P. F.; Fan, J. Z.; Fang, J.; Fang, S. S.; Fang, X.; Fang, Y.; Farinelli, R.; Fava, L.; Fedorov, O.; Feldbauer, F.; Felici, G.; Feng, C. Q.; Fioravanti, E.; Fritsch, M.; Fu, C. D.; Gao, Q.; Gao, X. L.; Gao, X. Y.; Gao, Y.; Gao, Z.; Garzia, I.; Goetzen, K.; Gong, L.; Gong, W. X.; Gradl, W.; Greco, M.; Gu, M. H.; Gu, Y. T.; Guan, Y. H.; Guo, A. Q.; Guo, L. B.; Guo, R. P.; Guo, Y.; Guo, Y. P.; Haddadi, Z.; Hafner, A.; Han, S.; Hao, X. Q.; Harris, F. A.; He, K. L.; Held, T.; Heng, Y. K.; Hou, Z. L.; Hu, C.; Hu, H. M.; Hu, J. F.; Hu, T.; Hu, Y.; Huang, G. S.; Huang, J. S.; Huang, X. T.; Huang, X. Z.; Huang, Y.; Huang, Z. L.; Hussain, T.; Ji, Q.; Ji, Q. P.; Ji, X. B.; Ji, X. L.; Jiang, L. W.; Jiang, X. S.; Jiang, X. Y.; Jiao, J. B.; Jiao, Z.; Jin, D. P.; Jin, S.; Johansson, T.; Julin, A.; Kalantar-Nayestanaki, N.; Kang, X. L.; Kang, X. S.; Kavatsyuk, M.; Ke, B. C.; Kiese, P.; Kliemt, R.; Kloss, B.; Kolcu, O. B.; Kopf, B.; Kornicer, M.; Kupsc, A.; Kühn, W.; Lange, J. S.; Lara, M.; Larin, P.; Leng, C.; Li, C.; Li, Cheng; Li, D. M.; Li, F.; Li, F. Y.; Li, G.; Li, H. B.; Li, H. J.; Li, J. C.; Li, Jin; Li, K.; Li, K.; Li, Lei; Li, P. R.; Li, Q. Y.; Li, T.; Li, W. D.; Li, W. G.; Li, X. L.; Li, X. N.; Li, X. Q.; Li, Y. B.; Li, Z. B.; Liang, H.; Liang, Y. F.; Liang, Y. T.; Liao, G. R.; Lin, D. X.; Liu, B.; Liu, B. J.; Liu, C. X.; Liu, D.; Liu, F. H.; Liu, Fang; Liu, Feng; Liu, H. B.; Liu, H. H.; Liu, H. H.; Liu, H. M.; Liu, J.; Liu, J. B.; Liu, J. P.; Liu, J. Y.; Liu, K.; Liu, K. Y.; Liu, L. D.; Liu, P. L.; Liu, Q.; Liu, S. B.; Liu, X.; Liu, Y. B.; Liu, Z. A.; Liu, Zhiqing; Loehner, H.; Lou, X. C.; Lü, H. J.; Lü, J. G.; Lu, Y.; Lu, Y. P.; Luo, C. L.; Luo, M. X.; Luo, T.; Luo, X. L.; Lü, X. R.; Ma, F. C.; Ma, H. L.; Ma, L. L.; Ma, M. M.; Ma, Q. M.; Ma, T.; Ma, X. N.; Ma, X. Y.; Ma, Y. M.; Maas, F. E.; Maggiora, M.; Mao, Y. J.; Mao, Z. P.; Marcello, S.; Messchendorp, J. G.; Min, J.; Min, T. J.; Mitchell, R. E.; Mo, X. H.; Mo, Y. J.; Morales Morales, C.; Muchnoi, N. Yu.; Muramatsu, H.; Nefedov, Y.; Nerling, F.; Nikolaev, I. B.; Ning, Z.; Nisar, S.; Niu, S. L.; Niu, X. Y.; Olsen, S. L.; Ouyang, Q.; Pacetti, S.; Pan, Y.; Patteri, P.; Pelizaeus, M.; Peng, H. P.; Peters, K.; Pettersson, J.; Ping, J. L.; Ping, R. G.; Poling, R.; Prasad, V.; Qi, H. R.; Qi, M.; Qian, S.; Qiao, C. F.; Qin, L. Q.; Qin, N.; Qin, X. S.; Qin, Z. H.; Qiu, J. F.; Rashid, K. H.; Redmer, C. F.; Ripka, M.; Rong, G.; Rosner, Ch.; Ruan, X. D.; Sarantsev, A.; Savrié, M.; Schoenning, K.; Schumann, S.; Shan, W.; Shao, M.; Shen, C. P.; Shen, P. X.; Shen, X. Y.; Sheng, H. Y.; Shi, M.; Song, W. M.; Song, X. Y.; Sosio, S.; Spataro, S.; Sun, G. X.; Sun, J. F.; Sun, S. S.; Sun, X. H.; Sun, Y. J.; Sun, Y. Z.; Sun, Z. J.; Sun, Z. T.; Tang, C. J.; Tang, X.; Tapan, I.; Thorndike, E. H.; Tiemens, M.; Ullrich, M.; Uman, I.; Varner, G. S.; Wang, B.; Wang, B. L.; Wang, D.; Wang, D. Y.; Wang, K.; Wang, L. L.; Wang, L. S.; Wang, M.; Wang, P.; Wang, P. L.; Wang, W.; Wang, W. P.; Wang, X. F.; Wang, Y.; Wang, Y. D.; Wang, Y. F.; Wang, Y. Q.; Wang, Z.; Wang, Z. G.; Wang, Z. H.; Wang, Z. Y.; Wang, Z. Y.; Weber, T.; Wei, D. H.; Weidenkaff, P.; Wen, S. P.; Wiedner, U.; Wolke, M.; Wu, L. H.; Wu, L. J.; Wu, Z.; Xia, L.; Xia, L. G.; Xia, Y.; Xiao, D.; Xiao, H.; Xiao, Z. J.; Xie, Y. G.; Xiu, Q. L.; Xu, G. F.; Xu, J. J.; Xu, L.; Xu, Q. J.; Xu, Q. N.; Xu, X. P.; Yan, L.; Yan, W. B.; Yan, W. C.; Yan, Y. H.; Yang, H. J.; Yang, H. X.; Yang, L.; Yang, Y. X.; Ye, M.; Ye, M. H.; Yin, J. H.; Yu, B. X.; Yu, C. X.; Yu, J. S.; Yuan, C. Z.; Yuan, W. L.; Yuan, Y.; Yuncu, A.; Zafar, A. A.; Zallo, A.; Zeng, Y.; Zeng, Z.; Zhang, B. X.; Zhang, B. Y.; Zhang, C.; Zhang, C. C.; Zhang, D. H.; Zhang, H. H.; Zhang, H. Y.; Zhang, J.; Zhang, J. J.; Zhang, J. L.; Zhang, J. Q.; Zhang, J. W.; Zhang, J. Y.; Zhang, J. Z.; Zhang, K.; Zhang, L.; Zhang, S. Q.; Zhang, X. Y.; Zhang, Y.; Zhang, Y. H.; Zhang, Y. N.; Zhang, Y. T.; Zhang, Yu; Zhang, Z. H.; Zhang, Z. P.; Zhang, Z. Y.; Zhao, G.; Zhao, J. W.; Zhao, J. Y.; Zhao, J. Z.; Zhao, Lei; Zhao, Ling; Zhao, M. G.; Zhao, Q.; Zhao, Q. W.; Zhao, S. J.; Zhao, T. C.; Zhao, Y. B.; Zhao, Z. G.; Zhemchugov, A.; Zheng, B.; Zheng, J. P.; Zheng, W. J.; Zheng, Y. H.; Zhong, B.; Zhou, L.; Zhou, X.; Zhou, X. K.; Zhou, X. R.; Zhou, X. Y.; Zhu, K.; Zhu, K. J.; Zhu, S.; Zhu, S. H.; Zhu, X. L.; Zhu, Y. C.; Zhu, Y. S.; Zhu, Z. A.; Zhuang, J.; Zotti, L.; Zou, B. S.; Zou, J. H.; BESIII Collaboration

2016-11-01

By analyzing 2.93 fb-1 data collected at the center-of-mass energy with the BESIII detector, we measure the absolute branching fraction of the semileptonic decay D+ → K̅0 e+νe to be ℬ(D + → K̅0 e+νe) = (8.59 ± 0.14 ± 0.21)% using , where the first uncertainty is statistical and the second systematic. Our result is consistent with previous measurements within uncertainties.. Supported by National Key Basic Research Program of China (2009CB825204, 2015CB856700), National Natural Science Foundation of China (NSFC) (10935007, 11125525, 11235011, 11305180, 11322544, 11335008, 11425524, 11475123), Chinese Academy of Sciences (CAS) Large-Scale Scientific Facility Program, CAS Center for Excellence in Particle Physics (CCEPP), Collaborative Innovation Center for Particles and Interactions (CICPI), Joint Large-Scale Scientific Facility Funds of NSFC and CAS (11179007, U1232201, U1332201, U1532101), CAS (KJCX2-YW-N29, KJCX2-YW-N45), 100 Talents Program of CAS, National 1000 Talents Program of China, INPAC and Shanghai Key Laboratory for Particle Physics and Cosmology, German Research Foundation DFG (Collaborative Research Center CRC-1044), Istituto Nazionale di Fisica Nucleare, Italy, Koninklijke Nederlandse Akademie van Wetenschappen (KNAW) (530-4CDP03), Ministry of Development of Turkey (DPT2006K-120470), National Natural Science Foundation of China (NSFC) (11405046, U1332103), Russian Foundation for Basic Research (14-07-91152), Swedish Resarch Council, U. S. Department of Energy (DE-FG02-04ER41291, DE-FG02-05ER41374, DE-SC0012069, DESC0010118), U.S. National Science Foundation, University of Groningen (RuG) and Helmholtzzentrum fuer Schwerionenforschung GmbH (GSI), Darmstadt, WCU Program of National Research Foundation of Korea (R32-2008-000-10155-0).

Ferroelectric properties and diffuse phase transition in (Pb,La)Zrsub(0.55)Tisub(0.45)O3 ceramics

International Nuclear Information System (INIS)

Wolters, M.

1976-01-01

A preparation technique for (Pb,La)Zrsub(0.55)Tisub(0.45)O 3 ceramics is described by which inhomogeneities are eliminated. Grain size effects are studied and ferroelectric-paraelectric phase-transitions are investigated by means of X-ray diffraction analysis and dielectric weak-field (permittivity) and high-field (dc bias and hysteresis) measurements

Direct measurement of the low temperature spin state transitions in La1-xSrxCoO3 (0.05 < x < 0.3)

Science.gov (United States)

Gulec, A.; Klie, R. F.

2014-12-01

Sr-doped LaCoO3 has a complex magnetic phase diagram, which is believed to be directly correlated to changes in the crystal structure and ordering of the Co3+ spin states. In this work, we study the low temperature Co3+-ion spin state transitions in Sr-doped LaCoO3 around the critical doping concentration where a metal to insulator transition has been observed using electron energy-loss spectroscopy of the O K-edge combined with the Co L-edge fine structure. We measure the local spin state of the Co3+-ions and we demonstrate that the Co3+ spin-state transition only occurs in La0.95Sr0.05CoO3 single-crystal materials in the temperature range accessible by LN2 in-situ cooling, while no structural symmetry change is observed. The presence of this low-temperature spin-state transition in La1-xSrxCoO3 (x < 0.17) has been proposed as the origin of the percolative magnetic ordering in doped LaCoO3.

Making the transition to ANSI/ASQC E4

International Nuclear Information System (INIS)

Wolfe, D.W.

1992-07-01

As ANSI/ASQC E4, Quality Systems Requirements for Environmental Programs, nears final form and formal issuance by the American National Standards Institute (ANSI) and the American Society for Quality Control (ASQC), numerous organizations will be developing and implementing quality assurance programs based on the criteria promulgated by ANSI/ASQC E4. The organizations to initially adopt ANSI/ASQC E4 will be those that already have quality assurance programs based either on ASME NQA -1 or EPA QAMS-005/8. This paper presents the changes/enhancements required to transition an ASME NQA -1 or EPA QAMS-005/80 based quality assurance program to a program which meets the requirements of ANSI/ASQC E4

First-order phase transition in the quantum spin glass at T=0

Energy Technology Data Exchange (ETDEWEB)

Viana, J. Roberto; Nogueira, Yamilles; Sousa, J. Ricardo de

2003-05-26

The van Hemmen model with transverse and random longitudinal field is studied to analyze the tricritical behavior in the quantum Ising spin glass at T=0. The free energy and order parameter are calculated for two types of probability distributions: Gaussian and bimodal. We obtain the phase diagram in the {omega}-H plane, where {omega} and H are the transverse and random longitudinal fields, respectively. For the case of Gaussian distribution the phase transition is of second order, while the bimodal distribution we observe second-order transition for high-transverse field and first-order transition for small transverse field, with a tricritical point in the phase diagram.

First-order phase transition in the quantum spin glass at T=0

International Nuclear Information System (INIS)

Viana, J. Roberto; Nogueira, Yamilles; Sousa, J. Ricardo de

2003-01-01

The van Hemmen model with transverse and random longitudinal field is studied to analyze the tricritical behavior in the quantum Ising spin glass at T=0. The free energy and order parameter are calculated for two types of probability distributions: Gaussian and bimodal. We obtain the phase diagram in the Ω-H plane, where Ω and H are the transverse and random longitudinal fields, respectively. For the case of Gaussian distribution the phase transition is of second order, while the bimodal distribution we observe second-order transition for high-transverse field and first-order transition for small transverse field, with a tricritical point in the phase diagram

Polar phase transitions in heteroepitaxial stabilized La0.5Y0.5AlO3 thin films

Science.gov (United States)

Liu, Shenghua; Zhang, Chunfeng; Zhu, Mengya; He, Qian; Chakhalian, Jak; Liu, Xiaoran; Borisevich, Albina; Wang, Xiaoyong; Xiao, Min

2017-10-01

We report on the fabrication of epitaxial La0.5Y0.5AlO3 ultrathin films on (001) LaAlO3 substrates. Structural characterizations by scanning transmission electron microscopy and x-ray diffraction confirm the high quality of the film with a - b + c - AlO6 octahedral tilt pattern. Unlike either of the nonpolar parent compound, LaAlO3 and YAlO3, second harmonic generation measurements on the thin films suggest a nonpolar-polar phase transition at T c near 500 K, and a polar-polar phase transition at T a near 160 K. By fitting the angular dependence of the second harmonic intensities, we further propose that the two polar structures can be assigned to the Pmc2 1 and Pmn2 1 space group, while the high temperature nonpolar structure belongs to the Pbnm space group.

Cubic-tetragonal phase transition in Ca sub 0 sub . sub 0 sub 4 Sr sub 0 sub . sub 9 sub 6 TiO sub 3 a combined specific heat and neutron diffraction study

CERN Document Server

Gallardo, M C; Romero, F J; Cerro, J D; Seifert, F; Redfern, S A T

2003-01-01

The specific heat corresponding to the tetragonal-to-cubic transition in Ca sub 0 sub . sub 0 sub 4 Sr sub 0 sub . sub 9 sub 6 TiO sub 3 perovskite has been measured by conduction calorimetry. The order parameter of the transition has been obtained by means of neutron diffraction at low temperatures. Comparison of calorimetric data with the evolution of the order parameter indicates that this transition seems to follow a mean field Landau potential as in SrTiO sub 3. The linear behaviour of the excess of entropy versus temperature suggests that a 2-4 Landau potential is sufficient to describe the transition.

Revisiting ρ1 Cancri e: A New Mass Determination of the Transiting Super-Earth

Science.gov (United States)

Endl, Michael; Robertson, Paul; Cochran, William D.; MacQueen, Phillip J.; Brugamyer, Erik J.; Caldwell, Caroline; Wittenmyer, Robert A.; Barnes, Stuart I.; Gullikson, Kevin

2012-11-01

We present a mass determination for the transiting super-Earth ρ1 Cancri e based on nearly 700 precise radial velocity (RV) measurements. This extensive RV data set consists of data collected by the McDonald Observatory planet search and published data from Lick and Keck observatories. We obtained 212 RV measurements with the Tull Coudé Spectrograph at the Harlan J. Smith 2.7 m Telescope and combined them with a new Doppler reduction of the 131 spectra that we have taken in 2003-2004 with the High-Resolution Spectrograph (HRS) at the Hobby-Eberly Telescope for the original discovery of ρ1 Cancri e. Using this large data set we obtain a five-planet Keplerian orbital solution for the system and measure an RV semi-amplitude of K = 6.29 ± 0.21 m s-1 for ρ1 Cnc e and determine a mass of 8.37 ± 0.38 M ⊕. The uncertainty in mass is thus less than 5%. This planet was previously found to transit its parent star, which allowed them to estimate its radius. Combined with the latest radius estimate from Gillon et al., we obtain a mean density of ρ = 4.50 ± 0.20 g cm-3. The location of ρ1 Cnc e in the mass-radius diagram suggests that the planet contains a significant amount of volatiles, possibly a water-rich envelope surrounding a rocky core. Based partly on observations obtained with the Hobby-Eberly Telescope, which is a joint project of the University of Texas at Austin, the Pennsylvania State University, Stanford University, Ludwig-Maximilians-Universität München, and Georg-August-Universität Göttingen.

Electric field-induced phase transitions in Li-modified Na{sub 0.5}K{sub 0.5}NbO{sub 3} at the polymorphic phase boundary

Energy Technology Data Exchange (ETDEWEB)

Iamsasri, Thanakorn; Jones, Jacob L., E-mail: jacobjones@ncsu.edu [Department of Materials Science and Engineering, North Carolina State University, Raleigh, North Carolina 27695 (United States); Department of Materials Science and Engineering, University of Florida, Gainesville, Florida 32611 (United States); Tutuncu, Goknur [Department of Materials Science and Engineering, University of Florida, Gainesville, Florida 32611 (United States); Uthaisar, Chunmanus; Pojprapai, Soodkhet [School of Ceramic Engineering, Institute of Engineering, Suranaree University of Technology, Nakorn Ratchasima 30000 (Thailand); Wongsaenmai, Supattra [Program in Materials Science, Faculty of Science, Maejo University, Chiang Mai 50290 (Thailand)

2015-01-14

The electric field-induced phase transitions in Li-modified Na{sub 0.5}K{sub 0.5}NbO{sub 3} at the polymorphic phase boundary (PPB) were observed using in situ X-ray diffraction. The ratio of monoclinic to tetragonal phase fraction was used as an indicator of the extent and reversibility of the phase transitions. The reversibility of the phase transition was greater in compositions further from the PPB. These results demonstrate that the field-induced phase transition is one of the origins of high piezoelectric properties in lead-free ferroelectric materials.

Transit Recovery of Kepler-167e: Providing JWST with an Unprecedented Jupiter-analog Exoplanet Target

Science.gov (United States)

Dalba, Paul; Muirhead, Philip; Tamburo, Patrick

2018-05-01

The Kepler Mission has uncovered a handful of long-period transiting exoplanets that orbit in the cold outer reaches of their systems, despite their low transit probabilities. Recent work suggests that cold gas giant exoplanet atmospheres are amenable to transmission spectroscopy (the analysis of the transit depth versus wavelength) enabling novel tests of planetary formation and evolution theories. Of particular scientific interest is Kepler-167e, a low-eccentricity Jupiter-analog exoplanet with a 1,071-day orbital period residing well beyond the snow-line. Transmission spectroscopy of Kepler-167e from JWST can reveal the composition of this planet's atmosphere, constrain its heavy-element abundance, and identify atmospheric photochemical processes. JWST characterization also enables unprecedented direct comparison with Jupiter and Saturn, which show a striking diversity in physical properties that is best investigated through comparative exoplanetology. Since Kepler only observed two transits of Kepler-167e, it is not known if this exoplanet exhibits transit timing variations (TTVs). About half of Kepler's long-period exoplanets have TTVs of up to 40 hours. Such a large uncertainty jeopardizes attempts to characterize the atmosphere of this unique Jovian exoplanet with JWST. To mitigate this risk, the upcoming third transit of Kepler-167e must be observed to test for TTVs. We propose a simple 10-hour, single-channel observation to capture ingress or egress of the next transit of Kepler-167e in December 2018. In the absence of TTVs, our observation will reduce the ephemeris uncertainty from an unknown value to approximately 3 minutes, thereby removing the risk in future transit observations with JWST. The excellent photometric precision of Spitzer is sufficient to identify the transit of Kepler-167e. Given the timing and nature of this program, Spitzer is the only observatory--on the ground or in space--that can make this pivotal observation.

Enhancement of the nonlinear optical absorption of the E7 liquid crystal at the nematic-isotropic transition

International Nuclear Information System (INIS)

Gomez, S.L.; Lenart, V.M.; Bechtold, I.H.; Figueiredo Neto, A.M.

2012-01-01

We present an experimental study of the nonlinear optical absorption of the eutectic mixture E7 at the nematic-isotropic phase transition by the Z-scan technique, under continuous-wave excitation at 532 nm. In the nematic region, the effective nonlinear optical coefficient P, which vanishes in the isotropic phase, is negative for the extraordinary beam and positive for an ordinary beam. The parameter SNL, whose definition in terms of the nonlinear absorption coefficient follows the definition of the optical-order parameter in terms of the linear dichroic ratio, behaves like an order parameter with critical exponent 0.22 ± 0.05, in good agreement with the tricritical hypothesis for the nematic isotropic transition. (author)

Angular analysis of the B-0 -> K*(0) e(+) e(-) decay in the low-q(2) region

NARCIS (Netherlands)

Aaij, R.; Adeva, B.; Adinolfi, M.; Affolder, A.; Ajaltouni, Z.; Akar, S.; Albrecht, J.; Alessio, F.; Alexander, M.; Ali, S.; Alkhazov, G.; Alvarez Cartelle, P.; Alves, A. A.; Amato, S.; Amerio, S.; Amhis, Y.; An, L.; Anderlini, L.; Andreassen, R.; Andreotti, M.; Andrews, J. E.; Appleby, R. B.; Gutierrez, O. Aquines; Archilli, F.; Artamonov, A.; Artuso, M.; Aslanides, E.; Auriemma, G.; Baalouch, M.; Bachmann, S.; Back, J. J.; Badalov, A.; Baesso, C.; Baldini, W.; Barlow, R. J.; Barschel, C.; Barsuk, S.; Barter, W.; Batozskaya, V.; Battista, V.; Beaucourt, L.; Beddow, J.; Bedeschi, F.; Bediaga, I.; Belogurov, S.; Belyaev, I.; Ben-Haim, E.; Bencivenni, G.; Benson, S.; Benton, J.; Berezhnoy, A.; Bernet, R.; Bertolin, A.; Bettler, M. -O.; van Beuzekom, M.; Bien, A.; Bifani, S.; Bird, T.; Bizzeti, A.; Blake, T.; Blanc, F.; Blouw, J.; Blusk, S.; Bocci, V.; Bondar, A.; Bondar, N.; Bonivento, W.; Borghi, S.; Borgia, A.; Borsato, M.; Bowcock, T. J. V.; Bowen, E.; Bozzi, C.; Brett, D.; Britsch, M.; Britton, T.; Brodzicka, J.; Brook, N. H.; Bursche, A.; Buytaert, J.; Cadeddu, S.; Calabrese, R.; Calvi, M.; Calvo Gomez, M.; Campana, P.; Perez, D. Campora; Capriotti, L.; Carbone, A.; Carboni, G.; Cardinale, R.; Cardini, A.; Carson, L.; Carvalho Akiba, K.; Casanova Mohr, R. C. M.; Casse, G.; Cassina, L.; Garcia, L. Castillo; Cattaneo, M.; Cauet, Ch.; Cenci, R.; Charles, M.; Charpentier, Ph.; Chefdeville, M.; Cheung, S. -F.; Chiapolini, N.; Chrzaszcz, M.; Vidal, X. Cid; Ciezarek, G.; Clarke, P. E. L.; Clemencic, M.; Cliff, H. V.; Closier, J.; Coco, V.; Cogan, J.; Cogneras, E.; Cogoni, V.; Cojocariu, L.; Collazuol, G.; Collins, P.; Comerma-Montells, A.; Contu, A.; Cook, A.; Coombes, M.; Coquereau, S.; Corti, G.; Corvo, M.; Counts, I.; Couturier, B.; Cowan, G. A.; Craik, D. C.; Crocombe, A. C.; Cruz Torres, M.; Cunliffe, S.; Currie, R.; D'Ambrosio, C.; Dalseno, J.; David, P.; David, P. N. Y.; Davis, A.; De Bruyn, K.; De Capua, S.; De Cian, M.; De Miranda, J. M.; De Paula, L.; De Silva, W.; De Simone, P.; Dean, C. -T.; Decamp, D.; Deckenhoff, M.; Del Buono, L.; Deleage, N.; Derkach, D.; Deschamps, O.; Dettori, F.; Dey, B.; Di Canto, A.; Di Domenico, A.; Di Ruscio, F.; Donleavy, S.; Dordei, F.; Dorigo, M.; Dosil Suarez, A.; Dossett, D.; Dovbnya, A.; Dreimanis, K.; Dujany, G.; Dupertuis, F.; Durante, P.; Dzhelyadin, R.; Dziurda, A.; Dzyuba, A.; Easo, S.; Egede, U.; Egorychev, V.; Eidelman, S.; Eisenhardt, S.; Eitschberger, U.; Ekelhof, R.; Eklund, L.; El Rifai, I.; Elsasser, Ch.; Ely, S.; Esen, S.; Evans, H. M.; Evans, T.; Falabella, A.; Faerber, C.; Farinelli, C.; Farley, N.; Farry, S.; Fay, R.; Ferguson, D.; Fernandez Albor, V.; Ferreira Rodrigues, F.; Ferro-Luzzi, M.; Filippov, S.; Fiore, M.; Fiorini, M.; Firlej, M.; Fitzpatrick, C.; Fiutowski, T.; Fol, P.; Fontana, M.; Fontanelli, F.; Forty, R.; Francisco, O.; Frei, C.; Frosini, M.; Furfaro, E.; Gallas Torreira, A.; Galli, D.; Gallorini, S.; Gambetta, S.; Gandelman, M.; Gandini, P.; Garcia Pardinas, J.; Garofoli, J.; Tico, J. Garra; Garrido, L.; Gascon, D.; Gaspar, C.; Gastaldi, U.; Gauld, R.; Gavardi, L.; Gazzoni, G.; Geraci, A.; Gersabeck, E.; Gersabeck, M.; Gershon, T.; Ghez, Ph.; Gianelle, A.; Giani, S.; Gibson, V.; Giubega, L.; Gligorov, V. V.; Goebel, C.; Golubkov, D.; Golutvin, A.; Gotti, C.; Gandara, M. Grabalosa; Graciani Diaz, R.; Cardoso, L. A. Granado; Grauges, E.; Graverini, E.; Graziani, G.; Grecu, A.; Greening, E.; Gregson, S.; Griffith, P.; Grillo, L.; Gruenberg, O.; Gui, B.; Gushchin, E.; Guz, Yu.; Gys, T.; Hadjivasiliou, C.; Haefeli, G.; Haen, C.; Haines, S. C.; Hall, S.; Hamilton, B.; Hampson, T.; Han, X.; Hansmann-Menzemer, S.; Harnew, N.; Harnew, S. T.; Harrison, J.; He, J.; Head, T.; Heijne, V.; Hennessy, K.; Henrard, P.; Henry, L.; Hernando Morata, J. A.; van Herwijnen, E.; Hess, M.; Hicheur, A.; Hill, D.; Hoballah, M.; Hombach, C.; Hulsbergen, W.; Hussain, N.; Hutchcroft, D.; Hynds, D.; Idzik, M.; Ilten, P.; Jacobsson, R.; Jalocha, J.; Jans, E.; Jawahery, A.; Jing, F.; John, M.; Johnson, D.; Jones, C. R.; Joram, C.; Jost, B.; Jurik, N.; Kandybei, S.; Kanso, W.; Karacson, M.; Karbach, T. M.; Karodia, S.; Kelsey, M.; Kenyon, I. R.; Kenzie, M.; Ketel, T.; Khanji, B.; Khurewathanakul, C.; Klaver, S.; Klimaszewski, K.; Kochebina, O.; Kolpin, M.; Komarov, I.; Koppenburg, P.; Korolev, M.; Kravchuk, L.; Kreplin, K.; Kreps, M.; Krocker, G.; Krokovny, P.; Kucewicz, W.; Kucharczyk, M.; Kudryavtsev, V.; Kurek, K.; Kvaratskheliya, T.; La Thi, V. N.; Lacarrere, D.; Lafferty, G.; Lai, A.; Lambert, D.; Lambert, R. W.; Lanfranchi, G.; Langenbruch, C.; Langhans, B.; Latham, T.; Lazzeroni, C.; Le Gac, R.; van Leerdam, J.; Lees, J. -P.; Lefevre, R.; Leflat, A.; Lefrancois, J.; Leroy, O.; Lesiak, T.; Leverington, B.; Likhomanenko, T.; Liles, M.; Lindner, R.; Linn, C.; Lionetto, F.; Lohn, S.; Longstaff, I.; Lopes, J. H.; Lowdon, P.; Lucchesi, D.; Luo, H.; Lupato, A.; Luppi, E.; Lupton, O.; Machefert, F.; Machikhiliyan, I. V.; Maciuc, F.; Maev, O.; Malde, S.; Malinin, A.; Manca, G.; Mancinelli, G.; Manning, P.; Mapelli, A.; Maratas, J.; Marchand, J. F.; Marconi, U.; Marin Benito, C.; Marino, P.; Maerki, R.; Marks, J.; Martellotti, G.; Martinelli, M.; Santos, D. Martinez; Martinez Vidal, F.; Martins Tostes, D.; Massafferri, A.; Matev, R.; Mathe, Z.; Matteuzzi, C.; Maurin, B.; Mazurov, A.; McCann, M.; McCarthy, J.; McNab, A.; McNulty, R.; McSkelly, B.; Meadows, B.; Meier, F.; Merk, M.; Milanes, D. A.; Minard, M. -N.; Moggi, N.; Molina Rodriguez, J.; Monteil, S.; Morandin, M.; Morawski, P.; Morda, A.; Morello, M. J.; Moron, J.; Morris, A. -B.; Mountain, R.; Muheim, F.; Mueller, K.; Mussini, M.; Muster, B.; Naik, P.; Nakada, T.; Nandakumar, R.; Nasteva, I.; Needham, M.; Neri, N.; Neubert, S.; Neufeld, N.; Neuner, M.; Nguyen, A. D.; Nguyen-Mau, C.; Nicol, M.; Niess, V.; Niet, R.; Nikitin, N.; Nikodem, T.; Novoselov, A.; O'Hanlon, D. P.; Oblakowska-Mucha, A.; Obraztsov, V.; Ogilvy, S.; Okhrimenko, O.; Oldeman, R.; Onderwater, C. J. G.; Orlandea, M.; Osorio Rodrigues, B.; Otalora Goicochea, J. M.; Otto, A.; Owen, P.; Oyanguren, A.; Pal, B. K.; Palano, A.; Palombo, F.; Palutan, M.; Papanestis, A.; Pappagallo, M.; Pappalardo, L. L.; Parkes, C.; Parkinson, C. J.; Passaleva, G.; Patel, G. D.; Patrignani, C.; Pearce, A.; Pellegrino, A.; Penso, G.; Altarelli, M. Pepe; Perazzini, S.; Perret, P.; Pescatore, L.; Pesen, E.; Petridis, K.; Petrolini, A.; Picatoste Olloqui, E.; Pietrzyk, B.; Pilar, T.; Pinci, D.; Pistone, A.; Playfer, S.; Plo Casasus, M.; Polci, F.; Poluektov, A.; Polyakov, I.; Polycarpo, E.; Popov, A.; Popov, D.; Popovici, B.; Potterat, C.; Price, E.; Price, J. D.; Prisciandaro, J.; Pritchard, A.; Prouve, C.; Pugatch, V.; Navarro, A. Puig; Punzi, G.; Qian, W.; Quagliani, R.; Rachwal, B.; Rademacker, J. H.; Rakotomiaramanana, B.; Rama, M.; Rangel, M. S.; Raniuk, I.; Rauschmayr, N.; Raven, G.; Redi, F.; Reichert, S.; Reid, M. M.; dos Reis, A. C.; Ricciardi, S.; Richards, S.; Rihl, M.; Rinnert, K.; Rives Molina, V.; Rodrigues, A. B.; Rodrigues, E.; Perez, P. Rodriguez; Roiser, S.; Romanovsky, V.; Romero Vidal, A.; Rotondo, M.; Rouvinet, J.; Ruf, T.; Ruiz, H.; Ruiz Valls, P.; Saborido Silva, J. J.; Sagidova, N.; Sail, P.; Saitta, B.; Salustino Guimaraes, V.; Sanchez Mayordomo, C.; Sanmartin Sedes, B.; Santacesaria, R.; Santamarina Rios, C.; Santovetti, E.; Sarti, A.; Satriano, C.; Satta, A.; Saunders, D. M.; Savrina, D.; Schindler, H.; Schlupp, M.; Schmelling, M.; Schmidt, B.; Schneider, O.; Schopper, A.; Schune, M. -H.; Schwemmer, R.; Sciascia, B.; Sciubba, A.; Semennikov, A.; Sepp, I.; Serra, N.; Serrano, J.; Sestini, L.; Seyfert, P.; Shapkin, M.; Shapoval, I.; Shcheglov, Y.; Shears, T.; Shekhtman, L.; Shevchenko, V.; Shires, A.; Coutinho, R. Silva; Simi, G.; Sirendi, M.; Skidmore, N.; Skillicorn, I.; Skwarnicki, T.; Smith, N. A.; Snoek, H.; Sokoloff, M. D.; Soler, F. J. P.; Soomro, F.; Souza, D.; Souza De Paula, B.; Spaan, B.; Spradlin, P.; Sridharan, S.; Stagni, F.; Stahl, M.; Stahl, S.; Steinkamp, O.; Stenyakin, O.; Sterpka, F.; Stevenson, S.; Stone, S.; Storaci, B.; Stracka, S.; Straticiuc, M.; Straumann, U.; Stroili, R.; Sutcliffe, W.; Swientek, K.; Swientek, S.; Syropoulos, V.; Szczekowski, M.; Szczypka, P.; Szumlak, T.; T'Jampens, S.; Teklishyn, M.; Tellarini, G.; Teubert, F.; van Tilburg, J.; Tisserand, V.; Tobin, M.; Todd, J.; Tolk, S.; Tomassetti, L.; Tonelli, D.; Topp-Joergensen, S.; Torr, N.; Tournefier, E.; Tourneur, S.; Trabelsi, K.; Tresch, M.; Trisovic, A.; Tsaregorodtsev, A.; Tsopelas, P.; Tuning, N.; Garcia, M. Ubeda; Ukleja, A.; Ustyuzhanin, A.; Uwer, U.; Vacca, C.; Vagnoni, V.; Valenti, G.; Vallier, A.; Gomez, R. Vazquez; Vazquez Regueiro, P.; Vazquez Sierra, C.; Vecchi, S.; Velthuis, J. J.; Veltri, M.; Veneziano, G.; Vesterinen, M.; Barbosa, J. V. V. B. Viana; Viaud, B.; Vieira, D.; Vieites Diaz, M.; Vilasis-Cardona, X.; Vollhardt, A.; Volyanskyy, D.; Voong, D.; Vorobyev, A.; Vorobyev, V.; Voss, C.; Waldi, R.; Wallace, C.; Wallace, R.; Wandernoth, S.; Ward, D. R.; Watson, N. K.; Websdale, D.; Whitehead, M.; Wiedner, D.; Wilkinson, G.; Wilschut, H. W.; Wilson, F. F.; Wimberley, J.; Wishahi, J.; Wislicki, W.; Witek, M.; Wormser, G.; Wotton, S. A.; Wright, S.; Wyllie, K.; Xie, Y.; Xing, Z.; Yang, Z.; Yuan, X.; Yushchenko, O.; Zangoli, M.; Zavertyaev, M.; Zhang, W. C.; Zhelezov, A.; Zhokhov, A.; Zhong, L.

2015-01-01

An angular analysis of the B-0 -> K(*0)e(+) e(-) decay is performed using a data sample, corresponding to an integrated luminosity of 3.0 fb(-1), collected by the LHCb experiment in pp collisions at centre-of-mass energies of 7 and 8TeV during 2011 and 2012. For the first time several observables

Raman spectroscopy, dielectric properties and phase transitions of Ag{sub 0.96}Li{sub 0.04}NbO{sub 3} ceramics

Energy Technology Data Exchange (ETDEWEB)

Niewiadomski, Adrian, E-mail: aniewiadomski@us.edu.pl [A. Chelkowski Institute of Physics, University of Silesia, Uniwersytecka 4, 40-007 Katowice (Poland); Kania, Antoni [A. Chelkowski Institute of Physics, University of Silesia, Uniwersytecka 4, 40-007 Katowice (Poland); Kugel, Godefroy E. [LMPOS, University of Metz and Supelec Metz, 2 rue E. Belin, Metz 57070 (France); Hafid, Mustapha [LPGC Dept. of Physics BP 133, Faculty of Science, Ibn Tofail University, 14000 Kenitra (Morocco); Sitko, Dorota [Institute of Physics, Pedagogical University, ul. Podchorazych 2, PL 30-084 Krakow (Poland)

2015-05-15

Highlights: • First Raman scattering studies of Ag{sub 0.96}Li{sub 0.04}NbO{sub 3}, allowed us to correlate temperature evolution of relaxational frequency γ{sub R}(T) with the Nb-ion dynamics and showed its changes at freezing temperature and ferrielectric transition. - Abstract: Silver lithium niobates Ag{sub 1−x}Li{sub x}NbO{sub 3} are promising lead free piezoelectrics. Good quality Ag{sub 0.96}Li{sub 0.04}NbO{sub 3} ceramics were obtained. Dielectric and DSC studies showed that, in comparison to AgNbO{sub 3,} temperatures of phase transitions slightly decrease. Dielectric studies pointed to enhancement of polar properties. Remnant polarisations achieves value of 0.6 μC/cm{sup 2}. Maximum of ϵ(T) dependences related to the relaxor-like ferroelectric/ferrielectric M{sub 1}–M{sub 2} transition becomes higher and more frequency dependent. Analysis of Raman spectra showed that two modes at 50 and 194 cm{sup −1} exhibit significant softening. Low frequency part of the Raman spectra which involve central peak and soft mode were analysed using two models. CP was assumed as relaxational vibration and described by Debye function. The slope of temperature dependences of relaxational frequency γ{sub R}(T) changes at approximately 470 and 330 K, indicating that slowing down process of relaxational vibrations changes in the vicinity of partial freezing of Nb-ion dynamics T{sub f} and further freezing at ferroelectric/ferrielectric phase transition.

Atomic scale 0-π transition and pairing symmetry in a Josephson junction with a ferromagnetic insulator

International Nuclear Information System (INIS)

Kawabata, S.; Kashiwaya, S.; Tanaka, Y.; Golubov, A. A.; Asano, Y.

2011-01-01

Full text: A superconducting ring with a π-junction made from superconductor (S) / ferromagnetic- metal (FM) / superconductor (S) exhibits a spontaneous current without an external magnetic field and the corresponding magnetic flux is half a flux quantum in the ground state. Such a π-ring provides so-called 'quiet qubit' that can be efficiently decoupled from the fluctuation of the external field. However, the usage of FM gives rise to strong Ohmic dissipation. Therefore, the realization of π-junctions without FM is highly desired for qubit applications. We theoretically consider the possibility of the π-junction formation in the mesoscopic Josephson junctions with ferromagnetic insulators (FI) by taking into account the band structure of such materials explicitly. In the case of the fully polarized FIs, e.g., La 2 BaCuO 5 (LBCO) and K 2 CuF 4 , we found the formation of a π-junction and a novel atomic-scale 0-π transition induced by increasing the FI thickness LF. In this talk, I will discuss a thermal stability and material-parameter dependences of the atomic-scale 0-π transition as well as possibility of the odd-frequency pairing in such systems. (author)

Thermophysical Properties and Structural Transition of Hg(0.8)Cd(0.2)Te Melt

Science.gov (United States)

Li, C.; Scripa, R. N.; Ban, H.; Lin, B.; Su, C.; Lehoczky, S. L.

2004-01-01

Thermophysical properties, namely, density, viscosity, and electrical conductivity of Hg(sub o.8)Cd(sub 0.2)Te melt were measured as a function of temperature. A pycnometric method was used to measure the melt density in the temperature range of 1072 to 1122 K. The viscosity and electrical conductivity were simultaneously determined using a transient torque method from 1068 to 1132 K. The density result from this study is within 0.3% of the published data. However, the current viscosity result is approximately 30% lower than the existing data. The electrical conductivity of Hg(sub o.8)Cd(sub 0.2)Te melt as a function of temperature, which is not available in the literature, is also determined. The analysis of the temperature dependent electrical conductivity and the relationship between the kinematic viscosity and density indicated that the structure of the melt appeared to be homogeneous when the temperature was above 1090 K. A structural transition occurred in the Hg(sub 0.8)Cd(0.2)Te melt as the temperature was decreased from 1090 K to the liquidus temperature.

Pressure-induced structural and semiconductor-semiconductor transitions in C o0.5M g0.5C r2O4

Science.gov (United States)

Rahman, S.; Saqib, Hajra; Zhang, Jinbo; Errandonea, D.; Menéndez, C.; Cazorla, C.; Samanta, Sudeshna; Li, Xiaodong; Lu, Junling; Wang, Lin

2018-05-01

The effect of pressure on the structural, vibrational, and electronic properties of Mg-doped Cr bearing spinel C o0.5M g0.5C r2O4 was studied up to 55 GPa at room-temperature using x-ray diffraction, Raman spectroscopy, electrical transport measurements, and ab initio calculations. We found that the ambient-pressure phase is cubic (spinel-type, F d 3 ¯m ) and underwent a pressure-induced structural transition to a tetragonal phase (space group I 4 ¯m 2 ) above 28 GPa. The ab initio calculation confirmed this first-order phase transition. The resistivity of the sample decreased at low pressures with the existence of a low-pressure (LP) phase and started to increase with the emergence of a high-pressure (HP) phase. The temperature dependent resistivity experiments at different pressures illustrated the wide band gap semiconducting nature of both the LP and HP phases with different activation energies, suggesting a semiconductor-semiconductor transition at HP. No evidence of chemical decomposition or a semiconductor-metal transition was observed in our studies.

Structural phase transitions of BaNbxTi1-xO3(0.0≤x≤0.5) thin films

International Nuclear Information System (INIS)

Guo Haizhong; Liu Lifeng; Ding Shuo; Lu Huibin; Zhou Yueliang; Cheng Bolin; Chen Zhenghao

2004-01-01

The phase transition behavior of BaNb x Ti 1-x O 3 (BNTO) (0.0≤x≤0.50) thin films grown on MgO substrates by laser molecular beam epitaxy was systematically investigated by using x-ray diffraction (XRD) and micro-Raman spectroscopy. The asymmetric rocking XRD scan measurements show that with an increase of Nb-doped content, the lattice parameters c and a increase while c/a ratio decreases, indicating a decrease of tetragonality of the BNTO films. The intensity of Raman signal decreases and the width of the bands broaden with increase of Nb-doped content. The results of XRD and Raman spectra indicate that at room temperature BNTO thin films with Nb≤10 at. % have tetragonal structure, however, for Nb≥20 at. %, BNTO thin films exhibit typical disordering cubic structure

Composition-induced structural phase transitions in the (Ba1-xLax)2In2O5+x (0=0.6) system

International Nuclear Information System (INIS)

Tenailleau, C.; Pring, A.; Moussa, S.M.; Liu, Y.; Withers, R.L.; Tarantino, S.; Zhang, M.; Carpenter, M.A.

2005-01-01

Composition-induced structural phase changes across the high temperature, fast oxide ion conducting (Ba 1-x La x ) 2 In 2 O 5+x , 0= orthorhombic transition, while the cubic->tetragonal transition could be continuous. Differences between the variation with composition of spectral parameters and of macroscopic strain parameters are consistent with a substantial order/disorder component for the transitions. There is also evidence for precursor effects within the cubic structure before symmetry is broken

QCD Factorizations in Exclusive γ*γ*→ρL0ρL0

International Nuclear Information System (INIS)

Pire, B.; Segond, M.; Szymanowski, L.; Wallon, S.

2008-01-01

The exclusive process e + e - →e + e - ρ L 0 ρ L 0 allows to study various dynamics and factorization properties of perturbative QCD. At moderate energy, we demonstrate how collinearQCD factorization emerges, involving either generalized distribution amplitudes (GDA) or transition distribution amplitudes (TDA). At higher energies, in the Regge limit of QCD, we show that it offers a promising probe of the BFKL resummation effects to be studied at ILC

High energy storage property and breakdown strength of Bi{sub 0.5}(Na{sub 0.82}K{sub 0.18}){sub 0.5}TiO{sub 3} ceramics modified by (Al{sub 0.5}Nb{sub 0.5}){sup 4+} complex-ion

Energy Technology Data Exchange (ETDEWEB)

Zhao, Yangyang [Guangxi Key Laboratory of Information Materials, Guilin University of Electronic Technology, Guilin 541004 (China); Xu, Jiwen, E-mail: csuxjw@126.com [Guangxi Key Laboratory of Information Materials, Guilin University of Electronic Technology, Guilin 541004 (China); Guangxi Experiment Center of Information Science, Guilin 541004 (China); Yang, Ling; Zhou, Changrong [Guangxi Key Laboratory of Information Materials, Guilin University of Electronic Technology, Guilin 541004 (China); Guangxi Experiment Center of Information Science, Guilin 541004 (China); Lu, Xiaopeng; Yuan, Changlai; Li, Qingning; Chen, Guohua; Wang, Hua [Guangxi Key Laboratory of Information Materials, Guilin University of Electronic Technology, Guilin 541004 (China)

2016-05-05

The influence of B-site (Al{sub 0.5}Nb{sub 0.5}){sup 4+} complex-ion substitution on the phase transition, microstructure, dielectric, ferroelectric, and energy-storage properties of Bi{sub 0.5}(Na{sub 0.82}K{sub 0.18}){sub 0.5}Ti{sub 1–x}(Al{sub 0.5}Nb{sub 0.5}){sub x}O{sub 3} (BNKT-xAN) ceramics were systematically investigated. BNKT-xAN ceramics showed single-phase perovskite structure without an obvious phase transition after adding AN. Compact and uniform microstructure with almost the same grain morphology and size was obtained. The AN doping produced slimmer P-E loops and thus improved energy storage property. Meanwhile, the energy storage density increases drastically, and a maximum value of 1.41 J/cm{sup 3} at 105 kV/cm was achieved in BNKT-0.08AN through increasing greatly its breakdown strength with more AN content. The temperature dependence of dielectric constant and dielectric loss of BNKT-xAN ceramics illustrated the obvious relaxor phase transition characteristics. Low ionic conductivity and electronic conductivity indicated the BNKT-xAN ceramics have excellent dielectric properties. These results indicated that the BNKT-AN system may be a promising lead-free material for high energy storage density capacitor. - Highlights: • The (Al{sub 0.5}Nb{sub 0.5}){sup 4+} B-site complex ions were introduced into BNT-BKT system. • The P-E loops were pinched and the P{sub r} and E{sub c} were decreased by complex ions. • Impedance spectrum revealed excellent dielectric property of complex-ion modified BNT-BNK. • Breakdown strength of BNT-BKT was enhanced by complex ions. • The energy storage density was improved to 1.41 J/cm{sup 3} by complex ions.

Pressure effect on magnetic and insulator-metal transition of La.sub.0.67./sub.Pb.sub.0.33./sub.Mn.sub.0.9./sub.Co.sub.0.1./sub.O.sub.2.97./sub. ceramic

Czech Academy of Sciences Publication Activity Database

Mihalik, M.; Zentková, M.; Antoňák, M.; Arnold, Zdeněk; Kamarád, Jiří; Skorokhod, Yuriy; Gritzner, G.; Kiss, L. F.

2012-01-01

Roč. 32, č. 1 (2012), s. 145-149 ISSN 0895-7959. [Conference of the European High Pressure Research Group (EHPRG) /49./. Budapest, 28.08.2011-02.09.2011] Grant - others:VEGA(SK) 2/0057/27 Institutional research plan: CEZ:AV0Z10100521 Keywords : magnetic transition: insulator-metal transition * hydrostatic pressure * manganite Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 0.901, year: 2012 www.tandfonline.com

First observation of the strongly forbidden transition 1S0 - 3P0 in Strontium, for an atomic clock with trapped atoms

International Nuclear Information System (INIS)

Courtillot, I.

2003-11-01

This thesis reports the first results towards the realization of an optical clock using trapped strontium atoms. This set up would combine advantages of the different approaches commonly used to develop an atomic frequency standard. The first part describes the cold atoms source which is implemented. A magneto-optical trap operating on the 1 S 0 - 1 P 1 transition at 461 nm is loaded from an atomic beam decelerated by a Zeeman slower. The 461 nm laser is obtained by sum-frequency mixing in a potassium titanyl phosphate (KTP) crystal. The second part is devoted to the different stages developed to achieve the direct excitation of the 1 S 0 - 3 P 0 clock transition in 87 Sr. This line has a theoretical natural width of 10 -3 Hz. Before this detection, we obtained an estimate of the resonance frequency by measuring absolute frequencies of several allowed optical transitions. (author)

The pseudo-binary mercury chalcogenide alloy HgSe sub 0 sub . sub 7 S sub 0 sub . sub 3 at high pressure: a mechanism for the zinc blende to cinnabar reconstructive phase transition

CERN Document Server

Kozlenko, D P; Ehm, L; Hull, S; Savenko, B N; Shchennikov, V V; Voronin, V I

2003-01-01

The structure of the pseudo-binary mercury chalcogenide alloy HgSe sub 0 sub . sub 7 S sub 0 sub . sub 3 has been studied by x-ray and neutron powder diffraction at pressures up to 8.5 GPa. A phase transition from the cubic zinc blende structure to the hexagonal cinnabar structure was observed at P approx 1 GPa. A phenomenological model of this reconstructive phase transition based on a displacement mechanism is proposed. Analysis of the geometrical relationship between the zinc blende and the cinnabar phases has shown that the possible order parameter for the zinc blende-cinnabar structural transformation is the spontaneous strain e sub 4. This assignment agrees with the previously observed high pressure behaviour of the elastic constants of some mercury chalcogenides.

The magnetic transition temperature tuned by strain in YMn0.9Ru0.1O3 thin films

Directory of Open Access Journals (Sweden)

L. P. Yang

2018-05-01

Full Text Available Epitaxial orthorhombic YMn0.9Ru0.1O3 films with different thickness have been grown on (001-SrTiO3 substrates by pulsed laser deposition (PLD. The crystal structure is well investigated by X-ray Diffraction. It is found that the out-of-plane parameter c slowly increases with decreasing thickness of samples because of the tensile strain between the films and substrates along c axis. The lengths of in-plane Mn-O bonds expand with the enhancement of strains, which is proved by Raman scatting. The magnetic measurements reveal that there exist two magnetic transition temperatures TN1 and TN2. The TN1 is close to that of orthorhombic YMnO3 bulk. With decreasing thickness of the films, TN1 keeps almost constant because of the small stain along c-axis. TN2, however, obviously increases from 117 K to 134 K, which could be related to the expansion of in-plane Mn-O bonds. Results show that the magnetic transition temperature of YMn0.9Ru0.1O3 films can be sensitively manipulated by the strain of the films.

Effective coupling constants for spin-flip and non spin-flip E1 transitions in A--90 nuclei

International Nuclear Information System (INIS)

Nakayama, Shintaro; Shibata, Tokushi; Kishimoto, Tadafumi; Sasao, Mamiko; Ejiri, Hiroyasu

1983-01-01

Radiative proton capture reactions through two isobaric analogue resonances (IAR) in 89 Y were studied, one was the 12.07 MeV 2dsub(5/2) state lying just above the neutron threshold energy Bsub(n) and another was the 14.48 MeV 2dsub(3/2) state lying well above Bsub(n). E1 transitions from these IAR's were studied for favoured cases with no spin-flip and no change of radial nodes, and for unfavoured cases spin-flip and/or change of radial nodes. At the 2dsub(3/2) IAR lying well above Bsub(n), the favoured transitions show the resonance feature, but the unfavoured ones not. At the 2dsub(5/2) IAR near Bsub(n), however, both the favoured and unfavoured transitions show the resonance feature. Anormalous resonant feature of the unfavoured transitions is interpreted mainly due to the compound process. Favoured transitions are all found to be reduced by factors -- 0.3 over the shell model values. (author)

Rectangular waveguide-to-coplanar waveguide transitions at U-band using e-plane probe and wire bonding

DEFF Research Database (Denmark)

Dong, Yunfeng; Johansen, Tom Keinicke; Zhurbenko, Vitaliy

2016-01-01

This paper presents rectangular waveguide-to-coplanar waveguide (CPW) transitions at U-band (40–60 GHz) using E-plane probe and wire bonding. The designs of CPWs based on quartz substrate with and without aluminum cover are explained. The single and double layer rectangular waveguide-to-CPW trans......This paper presents rectangular waveguide-to-coplanar waveguide (CPW) transitions at U-band (40–60 GHz) using E-plane probe and wire bonding. The designs of CPWs based on quartz substrate with and without aluminum cover are explained. The single and double layer rectangular waveguide......-to-CPW transitions using E-plane probe and wire bonding are designed. The proposed rectangular waveguide-to-CPW transition using wire bonding can provide 10 GHz bandwidth at U-band and does not require extra CPWs or connections between CPWs and chips. A single layer rectangular waveguide-to-CPW transition using E......-plane probe with aluminum package has been fabricated and measured to validate the proposed transitions. To the authors' best knowledge, this is the first time that a wire bonding is used as a probe for rectangular waveguide-to-CPW transition at U-band....

Nuclear wobbling motion and properties of E-2 transitions

Energy Technology Data Exchange (ETDEWEB)

Shimizu, Y R [Kyushu Univ., Fukuoka (Japan). Dept. of Physics; Matsuzaki, M [Fukuoka Univ. (Japan)

1992-08-01

The nuclear wobbling motion associated with the static triaxial deformation are discussed based on a microscopic theory. Properties of the E2-transitions between the one-phonon wobbling band and the yrast (vacuum) band are studied and their characteristic features are suggested. (author). 11 refs., 3 figs.

Experimental mapping of the absolute magnitude of the transition dipole moment function μe(R) of the Na2 AΣ1u+-XΣ1g+ transition

Science.gov (United States)

Ahmed, E. H.; Qi, P.; Beser, B.; Bai, J.; Field, R. W.; Huennekens, J. P.; Lyyra, A. M.

2008-05-01

The absolute magnitude of the transition dipole moment function μe(R) of the AΣ1u+-XΣ1g+ band system of Na2 was mapped experimentally over a relatively large range of internuclear distance R . The transition dipole moment matrix element of a set of rovibrational transitions between the AΣ1u+ and XΣ1g+ states was measured using the Autler-Townes effect. By employing the R -centroid approximation, or a fit to a polynomial function involving higher order R centroids, μe as a function of the internuclear distance was obtained. These Autler-Townes effect based measurements yield the absolute magnitude of μe , which can be used to test ab initio theoretical transition dipole moment functions or to “normalize” experimental transition moment functions obtained from intensity measurements, which in general give only the relative behavior of μe(R) .

Critical parameters near the ferromagnetic-paramagnetic phase transition in La{sub 0.7}A{sub 0.3}(Mn{sub 1-x}b{sub x})O{sub 3} (A=Sr; B=Ti and Al; x=0.0 and 0.05) compounds

Energy Technology Data Exchange (ETDEWEB)

Khiem, N.V. [Hongduc University, 307 Lelai Street, Thanhhoa City (Viet Nam)], E-mail: nvkhiem2002@yahoo.com; Phong, P.T. [Institute of Materials Science, Vietnamese Academy of Science and Technology, 18 Hoang Quoc Viet Road, Cau Giay District, Hanoi (Viet Nam); Bau, L.V. [Hongduc University, 307 Lelai Street, Thanhhoa City (Viet Nam); Nam, D.N.H.; Hong, L.V.; Phuc, N.X. [Institute of Materials Science, Vietnamese Academy of Science and Technology, 18 Hoang Quoc Viet Road, Cau Giay District, Hanoi (Viet Nam)

2009-07-15

The critical parameters provide important information concerning the interaction mechanisms near the paramagnetic-to-ferromagnetic transition. In this paper, we present a thorough study for the critical behavior of La{sub 0.7}A{sub 0.3}(Mn{sub 1-x}B{sub x})O{sub 3} (A=Sr; B=Ti and Al; x=0.0 and 0.05) polycrystalline samples near ferromagnetic-paramagnetic phase transition temperature by analyzing isothermal magnetization data. We have analyzed our dc-magnetization data near the transition temperature with the help of the modified Arrot plot, Kouvel-Fisher method. We have determined the critical temperature T{sub C} and the critical parameters {beta}, {gamma} and {delta}. With the values of T{sub C}, {beta} and {gamma}, we plot Mx(1-T/T{sub C}){sup -{beta}} vs. Hx(1-T/T{sub C}){sup -{gamma}}. All the data collapse on one of the two curves. This suggests that the data below and above T{sub C} obey scaling, following a single equation of state. Critical parameters for x=0 and x{sub Ti}=0.05 samples are between those predicted for a 3D-Heisenberg model and mean-field theory and for x{sub Al}=0.05 samples the values obtained for the critical parameters are close to those predicted by the mean-field theory.

Investigation on transition behavior and electrical properties of (K0.5Na0.51-xLixNb0.84Ta0.1Sb0.06O3 around polymorphic phase transition region

Directory of Open Access Journals (Sweden)

Chen Zhu

2014-01-01

Full Text Available (K0.5Na0.51-xLixNb0.84Ta0.1Sb0.06O3 (KNLNTS lead free ceramics with different Li concentration were fabricated by conventional solid-state reaction method. By increasing Li ions in KNLNTS, the grains grow up and the crystal structure changes from orthorhombic to tetragonal. When 0.03 ≤ x ≤ 0.05, the ceramics structure lays in PPT region. Polarization versus electric field (P-E hysteresis loops at room temperature show good ferroelectric properties and the remnant polarization decreases by increasing Li content while coercive electric keeps almost unchanged. In PPT region, taking x = 0.04 as an example, the sample shows excellent dielectric properties: the dielectric constant is 1159 and loss tangent is 0.04, while the piezoelectric constant d33 is 245 pC/N and kp is 0.44 at room temperature, it is promising for (K0.5Na0.51-xLixNb0.84Ta0.1Sb0.06O3 with 4 at. % Li to substitute PZT.

Crystalline-to-amorphous phase transition in irradiated silicon

International Nuclear Information System (INIS)

Seidman, D.N.; Averback, R.S.; Okamoto, P.R.; Baily, A.C.

1986-01-01

The amorphous(a)-to-crystalline (c) phase transition has been studied in electron(e - ) and/or ion irradiated silicon (Si). The irradiations were performed in situ in the Argonne High Voltage Microscope-Tandem Facility. The irradiation of Si, at 0 K, with 1-MeV e - to a fluence of 14 dpa failed to induce the c-to-a transition. Whereas an irradiation, at 0 K, with 1.0 or 1.5-MeV Kr+ ions induced the c-to-a transition by a fluence of approx.0.37 dpa. Alternatively a dual irradiation, at 10 0 K, with 1.0-MeV e - and 1.0 or 1.5-MeV Kr+ to a Kr+ fluence of 1.5 dpa - where the ratio of the displacement rates for e - to ions was approx.0.5 - resulted in the Si specimen retaining a degree of crystallinity. These results are discussed in terms of the degree of dispersion of point defects in the primary state of damage and the mobilities of point defects

Abnormal magnetization and field-induced transition in (La{sub 0.73}Bi{sub 0.27}){sub 0.67}Ca{sub 0.33}MnO{sub 3}

Energy Technology Data Exchange (ETDEWEB)

Li Haina; Wu Yuying [Department of Physics, Huazhong University of Science and Technology, Wuhan (China); Yu Hongwei [College of Science, Naval University of Engineering, Wuhan (China); Chen Ziyu [Department of Physics, Huazhong University of Science and Technology, Wuhan (China); Huang Yan; Wang Shaoliang; Li Liang [Wuhan Pulsed High Magnetic Field Center, Huazhong University of Science and Technology, Wuhan (China); Xia Zhengcai, E-mail: xia9020@hust.edu.c [Wuhan Pulsed High Magnetic Field Center, Huazhong University of Science and Technology, Wuhan (China)

2010-09-15

The magnetic field dependence of magnetization of Bi doped manganites (La{sub 1-x}Bi{sub x}){sub 0.67}Ca{sub 0.33}MnO{sub 3} (x=0.27) was investigated at different temperatures with a pulsed high magnetic field. A metamagnetic transition was observed in the magnetization measurement, which revealed the coexistence of charge ordering (CO) and ferromagnetic (FM) phases. With decreasing magnetic field, the field-induced FM phases remained stable even when the magnetic field decreased to zero. This result suggests that ferromagnetic interactions are enhanced due to the effect of the pulsed high magnetic field, which makes the doped manganites a good system for magnetoresistance materials.

The transcription factor snail controls epithelial-mesenchymal transitions by repressing E-cadherin expression

DEFF Research Database (Denmark)

Cano, A; Pérez-Moreno, M A; Rodrigo, I

2000-01-01

The Snail family of transcription factors has previously been implicated in the differentiation of epithelial cells into mesenchymal cells (epithelial-mesenchymal transitions) during embryonic development. Epithelial-mesenchymal transitions are also determinants of the progression of carcinomas......, occurring concomitantly with the cellular acquisition of migratory properties following downregulation of expression of the adhesion protein E-cadherin. Here we show that mouse Snail is a strong repressor of transcription of the E-cadherin gene. Epithelial cells that ectopically express Snail adopt...

Phase transitions and electrical characterizations of (K 0.5Na 0.5) 2x(Sr 0.6Ba 0.4) 5-xNb 10O 30 (KNSBN) ceramics with 'unfilled' and 'filled' tetragonal tungsten-bronze (TTB) crystal structure

KAUST Repository

Yao, Yingbang

2012-12-01

Alkali-doped strontium barium niobate (K 0.5Na 0.5) 2x(Sr 0.6Ba 0.4) 5-xNb 10O 30 (KNSBN) ceramics has been prepared by a conventional solid-state reaction method. The alkali-dopant concentration x has been varied from 0.24 to 1.15 so that the crystal structure was transformed from \\'unfilled\\' to \\'filled\\' tetragonal tungsten-bronze (TTB) structure. Apart from the change in the structural properties, the effects of the alkali-dopants on the phase transition as well as ferroelectric, piezoelectric and pyroelectric properties have also been investigated. Phase transitions have been studied in the temperature range of -200°C to 350°C. The origins of these phase transitions are discussed. The addition of the alkali-dopants enhances the ferroelectric, piezoelectric and pyroelectric properties of the KNSBN ceramics. Alkali-doping also favors abnormal grain growth and thus results in a porous microstructure, which might contribute to the enhancement of the pyroelectric performance. © 2012 Elsevier Ltd.

Phase transitions and electrical characterizations of (K 0.5Na 0.5) 2x(Sr 0.6Ba 0.4) 5-xNb 10O 30 (KNSBN) ceramics with 'unfilled' and 'filled' tetragonal tungsten-bronze (TTB) crystal structure

KAUST Repository

Yao, Yingbang; Mak, C. L.; Ploss, Bernd

2012-01-01

Alkali-doped strontium barium niobate (K 0.5Na 0.5) 2x(Sr 0.6Ba 0.4) 5-xNb 10O 30 (KNSBN) ceramics has been prepared by a conventional solid-state reaction method. The alkali-dopant concentration x has been varied from 0.24 to 1.15 so that the crystal structure was transformed from 'unfilled' to 'filled' tetragonal tungsten-bronze (TTB) structure. Apart from the change in the structural properties, the effects of the alkali-dopants on the phase transition as well as ferroelectric, piezoelectric and pyroelectric properties have also been investigated. Phase transitions have been studied in the temperature range of -200°C to 350°C. The origins of these phase transitions are discussed. The addition of the alkali-dopants enhances the ferroelectric, piezoelectric and pyroelectric properties of the KNSBN ceramics. Alkali-doping also favors abnormal grain growth and thus results in a porous microstructure, which might contribute to the enhancement of the pyroelectric performance. © 2012 Elsevier Ltd.

Internal friction and longitudinal modulus behaviour of multiferroic PbZr0.52Ti0.48O3+Ni0.93Co0.02Mn0.05Fe1.95O4-δ particulate composites

International Nuclear Information System (INIS)

Ramana, M Venkata; Sreenivasulu, G; Reddy, N Ramamanohar; Kumar, K V Siva; Murty, B S; Murthy, V R K

2007-01-01

Multiferroic particulate composites with composition xNi 0.93 Co 0.02 Mn 0.5 Fe 1.95 O 4-δ + (1 - x)PbZr 0.52 Ti 0.48 O 3 where the molar fraction x varies as 0, 0.1, 0.2, 0.3, 0.4 and 0.5 were prepared by the conventional ceramic method. The presence of two phases was confirmed by x-ray diffraction and scanning electron microscopy. The temperature variation of the longitudinal modulus (L) and the internal friction (Q -1 ) of these particulate composites at 104.387 kHz was studied in the wide temperature range 30-420 deg. C. The temperature variation of the longitudinal modulus (L) in each composition of these particulate composites showed two abrupt minima. One minimum coincided with the ferroelectric-paraelectric Curie transition temperature (θ E ) and the other with the ferrimagnetic-paramagnetic Curie transition (θ M ) temperature. The internal friction (Q -1 ) measurements also showed two sharp peaks in each composition corresponding to those temperatures where the minima were noticed in the temperature variation of the longitudinal modulus behaviour. The Curie transition temperature of pure ferrite was found to be 560 deg. C. Addition of 10% of ferrite to ferroelectric in a magnetoelectric (ME) composite resulted in a 360 deg. C fall in θ M and with a further increase in ferrite content the θ M variation was found to be very nominal. However, no significant ferroelectric Curie transition temperature shift could be noticed. This behaviour is explained in the light of structural phase transitions in these multiferroic particulate composites. These ME composites were prepared with a view to using them as ME sensors and transducers

Evidence of spin transition and charge order in cobalt substituted La sub 0 sub . sub 7 Ca sub 0 sub . sub 3 MnO sub 3

CERN Document Server

Srivastava, C M; Gundurao, T K; Nigam, A K; Bahadur, D

2003-01-01

The transport and magnetic studies of a series of compounds having the general formula La sub 0 sub . sub 7 Ca sub 0 sub . sub 3 Mn sub 1 sub - sub x Co sub x O sub 3 (0.1 = 0.25 there is a clear spin transition at low temperature from the high to the low spin state of trivalent cobalt and this leads to change in ferromagnetic (FM) and antiferromagnetic (AFM) phases. For x >= 0.25 there are two transitions for each value of x: the upper one gives the FM and AFM spin arrangement depending upon whether the DE or the SE dominates; the lower one is obtained due to the transition from the high to the low spin state of the trivalent cobalt ion.

A measurement of the e+e- decay width of the Z0

International Nuclear Information System (INIS)

Yamartino, J.M.

1994-02-01

This thesis presents a measurement of the partial decay width of the Z 0 to e + e - using data recorded by the SLD at the SLAC Linear Collider during the 1992 run. Based on 354 nb -1 of data, the decay width, Γ ee is measured to be 82.4 ± 3.6/3.7 ± 0.8 MeV where the first error is statistical and the second is systematic. By combining this measurement of Γ ee with the SLD measurement of A LR , the magnitude of the effective vector and axial-vector coupling constants of the electron, anti g v e and anti g a e , are determined to be 0.024 ± 0.011 and 0.498 ± 0.011 respectively

Observation of inverse hysteresis in the E to H mode transitions in inductively coupled plasmas

International Nuclear Information System (INIS)

Lee, Min-Hyong; Chung, Chin-Wook

2010-01-01

An inverse hysteresis is observed during the E mode to H mode transition in low pressure argon inductively coupled plasmas. The transition is accompanied by an evolution of electron energy distribution from the bi-Maxwellian to the Maxwellian distribution. The mechanism of this inversion is not clear. However, we think that the bi-Maxwellian electron energy distribution in E mode, where the proportion of high energy electron is much higher than the Maxwellian distribution, would be one of the reasons for the observed inverse hysteresis. As the gas pressure increases, the inverse hysteresis disappears and the E to H mode transition follows the scenario of usual hysteresis.

Second order magnetic phase transition and scaling analysis in iron doped manganite La0.7Ca0.3Mn1−xFexO3 compounds

International Nuclear Information System (INIS)

Ginting, Dianta; Nanto, Dwi; Denny, Yus Rama; Tarigan, Kontan; Hadi, Syamsul; Ihsan, Mohammad; Rhyee, Jong-Soo

2015-01-01

We investigated magnetic properties of La 0.7 Ca 0.3 Mn 1−x Fe x O 3 (x=0.09 and 0.11) compounds in terms of isothermal magnetization analysis and scaling behavior with various critical exponents. From the Landau theory of magnetic phase transition, we found that the paramagnetic to ferromagnetic phase transition in La 0.7 Ca 0.3 Mn 1−x Fe x O 3 (x=0.09 and 0.11) compounds is the type of second order magnetic transition (SOMT), which contrary to the first order magnetic transition (FOMT) for low Fe-doped compounds (x<0.09) in previous reports. When we investigate the critical behavior of the compounds near T=T c by the modified Arrott plot, Kouvel–Fisher plots, and critical isothermal analysis, the estimated critical exponents β, γ, and δ are in between the theoretically predicted values for three-dimensional Heisenberg and mean-field interaction models. It is noteworthy that the scaling relations are obeyed in terms of renormalization magnetization m=ε −β M(H,ε) and renormalized field h=|ε| β+γ H. Temperature-dependent effective exponents β eff and γ eff correspond to the ones of disordered ferromagnets. It is shown that the magnetic state of the compounds is not fully described by the conventional localized-spin interaction model because the ferromagnetic interaction has itinerant character by increasing Fe-doping concentration. - Highlights: • The ferromagnetic phase transition is of second order in La 0.7 Ca 0.3 Mn 1−x Fe x O 3 . • The critical exponents are in between the 3D Heisenberg and mean-field models. • The ferromagnetic interaction becomes more itinerant by Fe-doping

Investigation of the structural, optical and dielectric properties of highly (1 0 0)-oriented (Pb{sub 0.60}Ca{sub 0.20}Sr{sub 0.20})TiO{sub 3} thin films on LaNiO{sub 3} bottom electrode

Energy Technology Data Exchange (ETDEWEB)

Pontes, D.S.L. [Laboratorio Interdisciplinar de Eletroquimica e Cerâmica, Department of Chemistry, Universidade Federal de São Carlos, Via Washington Luiz, Km 235, P.O. Box 676, 13565-905 São Carlos, São Paulo (Brazil); Pontes, F.M., E-mail: fenelon@fc.unesp.br [Department of Chemistry, Universidade Estadual Paulista, P.O. Box 473, 17033-360 Bauru, São Paulo (Brazil); Chiquito, A.J. [NanO LaB, Transporte Eletrônico em Nanoestruturas, Department of Physics, Universidade Federal de São Carlos, Via Washington Luiz, Km 235, P.O. Box 676, 13565-905 São Carlos, São Paulo (Brazil); Longo, E. [Laboratorio Interdisciplinar de Eletroquimica e Cerâmica, Department of Chemistry, Universidade Federal de São Carlos, Via Washington Luiz, Km 235, P.O. Box 676, 13565-905 São Carlos, São Paulo (Brazil); Institute of Chemistry, Universidade Estadual Paulista, Araraquara, São Paulo (Brazil)

2014-07-01

Highlights: • Highly (h 0 0) oriented LNO and PCST thin films were grown on LAO(1 0 0) substrate. • PCST/LNO/LAO structure shown classic ferroelectric–paraelectric phase transition. • PCST/LNO/LAO structure shows superior dielectric properties. • PCST/LAO films showed a direct allowed optical transition. - Abstract: Highly (1 0 0)-oriented Pb{sub 0.60}Ca{sub 0.20}Sr{sub 0.20}TiO{sub 3}/LNO/LAO structure was fabricated using a chemical deposition process via spin-coating technique. XRD revealed that both LNO and Pb{sub 0.60}Ca{sub 0.20}Sr{sub 0.20}TiO{sub 3} films grown on LAO(1 0 0) substrate and LNO/LAO(1 0 0) structure were crystallized to be highly (h 0 0)-oriented, respectively. AFM images revealed smooth surfaces, spherical-shaped grains and a crack-free surface with a roughness of about 3–7 nm. The tetragonal perovskite phase was confirmed by Raman spectroscopy for Pb{sub 0.60}Ca{sub 0.20}Sr{sub 0.20}TiO{sub 3}/LNO/LAO and Pb{sub 0.60}Ca{sub 0.20}Sr{sub 0.20}TiO{sub 3}/LAO structures. The optical transmittance of 340 nm thick Pb{sub 0.60}Ca{sub 0.20}Sr{sub 0.20}TiO{sub 3} films on a LAO(1 0 0) substrate exhibited an average transmittance above 80% in the wavelength range of 500–1000 nm and an optical band gap E{sub g} of 3.56 and 2.87 eV for the direct and indirect transition processes, respectively. The Au/Pb{sub 0.60}Ca{sub 0.20}Sr{sub 0.20}TiO{sub 3}/LNO/LAO structure has a hysteresis loop with remnant polarization, P{sub r}, of 12 μC/cm{sup 2}, and a coercive field, E{sub c}, of 46 kV/cm for an electric field at 370 kV/cm along with a dielectric constant over 1200.

A resonant ultrasound spectroscopy study of the phase transitions in Na0.75CoO2

Science.gov (United States)

Keppens, Veerle; Sergienko, Ivan; Jin, Rongying

2005-03-01

The layered transition metal oxides NaxCoO2 have attracted much interest in the past few years. Crystals with the x˜0.75 composition undergo an order-disorder transition near 340 K, a spin-density-wave transition near 22 K and other subtle transitions at intermediate temperatures. These phase transitions, likely related to a rearrangement of the Na atoms among the available sites, have been mapped out using resonant ultrasound spectroscopy. The results are modeled within the Landau theory for second order phase transitions. [Oak Ridge National Laboratory is managed by UT-Battelle, LLC, for the U.S. Dept. of Energy under contract DE-AC05-00OR22725

Type-I pseudo-first-order phase transition induced electrocaloric effect in lead-free Bi0.5Na0.5TiO3-0.06BaTiO3 ceramics

Science.gov (United States)

Li, Feng; Chen, Guorui; Liu, Xing; Zhai, Jiwei; Shen, Bo; Li, Shandong; Li, Peng; Yang, Ke; Zeng, Huarong; Yan, Haixue

2017-05-01

In this study, the electrocaloric effect (ECE) of Bi0.5Na0.5TiO3-0.06BaTiO3 (BNT-0.06BT) ceramic has been directly measured using a home-made adiabatic calorimeter. The maximum adiabatic temperature change (ΔT) approaches 0.86 K under an electric field of 5 kV/mm at 110 °C, which provides experimental evidence for optimizing the ECE near the type-I pseudo-first-order phase transition (PFOPT). Most importantly, a considerable ΔT value can be maintained over a wide temperature range well above the temperature of the PFOPT under a high electric field. In addition, ΔT is closely related to the structural transition and electric field strength. This work provides a guideline to investigate the high ECE in BNT-based ferroelectric ceramics for applications in cooling technologies.

Electric monopole transitions from low energy excitations in nuclei

CERN Document Server

Wood, J L; De Coster, C; Heyde, Kris L G

1999-01-01

Electric monopole (E0) properties are studied across the entire nuclear mass surface. Besides an introductory discussion of various model results (shell model, geometric vibrational and rotational models, algebraic models), we point out that many of the largest E0 transition strengths, $\\rho^2$(E0), are associated with shape mixing. We discuss in detail the manifestation of E0 transitions and present extensive data for~: single-closed shell nuclei, vibrational nuclei, well-deformed nuclei, nuclei that exhibit sudden ground-state changes, and nuclei that exhibit shape coexistence and intruder states. We also give attention to light nuclei, odd-A nuclei, and illustrate a suggested relation between $\\rho^2$(E0) and isotopic shifts.

Monopole conversion hidden by penetration effect in magnetic dipole transitions

International Nuclear Information System (INIS)

Bikit, I.; Anichin, I.; Marinkov, L.

1977-01-01

The 191 keV 197 Au nad 340 keV 233 U transitions are investigated and the effect of penetration into the M1-component is accounted for. Theoretical internal conversion coefficients (ICC) and electron parameters to account for the penetration effect have been obtained by interpolating the data of the Hager and Zeltzer tables. The ICC values and ratios are analyzed under the assumption that the 191 keV 197 Au transition has multipolarities M1 + E2 and E 0 +M1. A common overlapping occurs when the nuclear penetration parameter lambda for magnetic dipole transition is lambda = 34.2+-2.2. For the 340 keV 233 U transition the ICC has been found to equal αk=0.69+-0.07, and the relative conversion-line intensities have been determined. It is concluded that the 191 keV 197 Au nad 340 keV 233 U transitions involve an electric monopole component concealed by the penetration effect in the M1-conversion. The matrix elements of the E0-transition have been evaluated

The low-temperature phase separation in Pr.sub.0.5./sub.Ca.sub.0.5./sub.CoO.sub.3./sub..

Czech Academy of Sciences Publication Activity Database

Chichev, A.; Hejtmánek, Jiří; Jirák, Zdeněk; Knížek, Karel; Maryško, Miroslav; Dlouhá, M.; Vratislav, S.

2007-01-01

Roč. 316, - (2007), e728-e730 ISSN 0304-8853 R&D Projects: GA AV ČR IAA100100611 Institutional research plan: CEZ:AV0Z10100521 Keywords : transition metal oxide * spin-state transition * neutron diffraction Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 1.704, year: 2007

Science with the space-based interferometer eLISA. II. Gravitational waves from cosmological phase transitions

International Nuclear Information System (INIS)

Caprini, Chiara; Hindmarsh, Mark; Helsinki Univ.; Huber, Stephan

2016-04-01

We investigate the potential for the eLISA space-based interferometer to detect the stochastic gravitational wave background produced by strong first-order cosmological phase transitions. We discuss the resulting contributions from bubble collisions, magnetohydrodynamic turbulence, and sound waves to the stochastic background, and estimate the total corresponding signal predicted in gravitational waves. The projected sensitivity of eLISA to cosmological phase transitions is computed in a model-independent way for various detector designs and configurations. By applying these results to several specific models, we demonstrate that eLISA is able to probe many well-motivated scenarios beyond the Standard Model of particle physics predicting strong first-order cosmological phase transitions in the early Universe.

Research on transition undulator radiation

International Nuclear Information System (INIS)

Lu Shuzhuang; Dai Zhimin; Zhao Xiaofeng

2000-01-01

The theory of transition undulator radiation was described first, then the properties of infrared and far-infrared transition undulator radiation of SSRF U9.0 were explored by the methods of analytical treatment and numerical simulation, and the influence of beam energy spread, emittance, and magnetic field errors on transition undulator radiation was given also. It was shown that the flux density of the infrared and far-infrared transition undulator radiation of the SSRF U9.0 was high (e.g., the maximum flux density might reach 35 x 10 13 photons/(s·mrad 2 ·BW), collecting angle φ = 0.23 mrad, and the effects of beam energy spread, emittance and magnetic field errors on the radiation flux density were small

Phase transition in metastable perovskite Pb(AlNb)0,5O3

International Nuclear Information System (INIS)

Zhabko, T.E.; Olekhnovich, N.M.; Shilin, A.D.

1987-01-01

Dielectric properties of metastable perovskite Pb(AlNb) 0.5 O 3 and X-ray temperature investigations of both perovskite and pyrochlore modifications of the given compound are studied. Samples with the perovskite structure are prepared from the pyrochlorephase at 4-5 GPa pressure and 1170-1270 K. Ferroelectric phase transition is shown to occur in the metastable perovskite phase Pb(AlNb) 0.5 O 3 at 170 K

E-H mode transition in low-pressure inductively coupled nitrogen-argon and oxygen-argon plasmas

International Nuclear Information System (INIS)

Lee, Young Wook; Lee, Hye Lan; Chung, T. H.

2011-01-01

This work investigates the characteristics of the E-H mode transition in low-pressure inductively coupled N 2 -Ar and O 2 -Ar discharges using rf-compensated Langmuir probe measurements and optical emission spectroscopy (OES). As the ICP power increases, the emission intensities from plasma species, the electron density, the electron temperature, and the plasma potential exhibit sudden changes. The Ar content in the gas mixture and total gas pressure have been varied in an attempt to fully characterize the plasma parameters. With these control parameters varying, the changes of the transition threshold power and the electron energy distribution function (EEDF) are explored. In N 2 -Ar and O 2 -Ar discharges at low-pressures of several millitorr, the transition thresholds are observed to decrease with Ar content and pressure. It is observed that in N 2 -Ar plasmas during the transition, the shape of the EEDF changes from an unusual distribution with a flat hole near the electron energy of 3 eV in the E mode to a Maxwellian distribution in the H mode. However, in O 2 -Ar plasmas, the EEDFs in the E mode at low Ar contents show roughly bi-Maxwellian distributions, while the EEDFs in the H mode are observed to be nearly Maxwellian. In the E and H modes of O 2 -Ar discharges, the dissociation fraction of O 2 molecules is estimated using optical emission actinometry. During the E-H mode transition, the dissociation fraction of molecules is also enhanced.

First observation of the strongly forbidden transition {sup 1}S{sub 0} - {sup 3}P{sub 0} in Strontium, for an atomic clock with trapped atoms; Premiere observation de la transition fortement interdite {sup 1}S{sub 0} - {sup 3}P{sub 0} du strontium, pour une horloge optique a atomes pieges

Energy Technology Data Exchange (ETDEWEB)

Courtillot, I

2003-11-01

This thesis reports the first results towards the realization of an optical clock using trapped strontium atoms. This set up would combine advantages of the different approaches commonly used to develop an atomic frequency standard. The first part describes the cold atoms source which is implemented. A magneto-optical trap operating on the {sup 1}S{sub 0}-{sup 1}P{sub 1} transition at 461 nm is loaded from an atomic beam decelerated by a Zeeman slower. The 461 nm laser is obtained by sum-frequency mixing in a potassium titanyl phosphate (KTP) crystal. The second part is devoted to the different stages developed to achieve the direct excitation of the {sup 1}S{sub 0}-{sup 3}P{sub 0} clock transition in {sup 87}Sr. This line has a theoretical natural width of 10{sup -3} Hz. Before this detection, we obtained an estimate of the resonance frequency by measuring absolute frequencies of several allowed optical transitions. (author)

Integrating E-Learning 2.0 into Online Courses

Science.gov (United States)

Yuen, Steve Chi-Yin

2014-01-01

This paper provides an overview of e-learning 2.0 concepts and presents a case study that involves the design, development, and teaching of two online courses based on e-learning 2.0 concepts. The design and the construction of e-learning 2.0 courses, and their effects on the students' learning experience are examined. In addition, students'…

High-Performance, 0.6-eV, GA0.32In0.68As/In0.32P0.68 Thermophotovoltaic Converters and Monolithically Interconnected Modules

International Nuclear Information System (INIS)

Duda, A.; Murray, C.S.

1998-01-01

Recent progress in the development of high-performance, 0.6-eV Ga0.32In0.68As/InAs0.32P0.68 thermophotovoltaic (TPV) converters and monolithically interconnected modules (MIMs) is described. The converter structure design is based on using a lattice-matched InAs0.32P0.68/Ga0.32In0.68As/InAs0.32P0.68 double-heterostructure (DH) device, which is grown lattice-mismatched on an InP substrate, with an intervening compositionally step-graded region of InAsyP1-y. The Ga0.32In0.68As alloy has a room-temperature band gap of 0.6 eV and contains a p/n junction. The InAs0.32P0.68 layers have a room-temperature band gap of 0.96 eV and serve as passivation/confinement layers for the Ga0.32In0.68As p/n junction. InAsyP1-y step grades have yielded DH converters with superior electronic quality and performance characteristics. Details of the microstructure of the converters are presented. Converters prepared for this work were grown by atmospheric-pressure metalorganic vapor-phase epitaxy (APMOVPE) and were processed using a combination of photolithography, wet-chemical etching, and conventional metal and insulator deposition techniques. Excellent performance characteristics have been demonstrated for the 0.6-eV TPV converters. Additionally, the implementation of MIM technology in these converters has been highly successful

Tetragonal-to-Tetragonal Phase Transition in Lead-Free (KxNa1−xNbO3 (x = 0.11 and 0.17 Crystals

Directory of Open Access Journals (Sweden)

Dabin Lin

2014-06-01

Full Text Available Lead free piezoelectric crystals of (KxNa1−xNbO3 (x = 0.11 and 0.17 have been grown by the modified Bridgman method. The structure and chemical composition of the obtained crystals were determined by X-ray diffraction (XRD and electron probe microanalysis (EPMA. The domain structure evolution with increasing temperature for (KxNa1−xNbO3 (x = 0.11 and 0.17 crystals was observed using polarized light microscopy (PLM, where distinguished changes of the domain structures were found to occur at 400 °C and 412 °C respectively, corresponding to the tetragonal to tetragonal phase transition temperatures. Dielectric measurements performed on (K0.11Na0.89NbO3 crystals exhibited tetragonal to tetragonal and tetragonal to cubic phase transitions temperatures at 405 °C and 496 °C, respectively.

Optical transition radiation interferometry for the A0 photoinjector

International Nuclear Information System (INIS)

Kazakevich, G.; Novosibirsk, IYF; Edwards, H.; Fliller, R.; Nagaitsev, S.; Ruan, J.; Thurman-Keup, R.; Fermilab

2008-01-01

Optical Transition Radiation Interferometry (OTRI) is a promising diagnostic technique and has been successfully developed and used for investigation of relativistic beams. For mid-energy accelerators the technique is traditionally based on thin polymer films (the first one is being transparent for visible light), which causes beam multiple scattering of about 1 mrad. A disadvantage of those films is unacceptable vacuum properties for photoinjectors and accelerators using superconducting cavities. We have studied the application of thin mica sheets for the OTRI diagnostics at the A0 Photoinjector in comparison with 2.5 (micro)m thick Mylar films. This diagnostic is also applicable for the ILCTA-NML accelerator test facility that is planned at Fermilab. This report discusses the experimental setups of the OTR interferometer for the A0 Photoinjector and presents comparisons of simulations and measurements obtained using Mylar and mica-based interferometers

Spin transitions in La{sub 0.7} Ba{sub 0.3}CoO{sub 3} thin films revealed by combining Raman spectroscopy and X-ray diffraction

Energy Technology Data Exchange (ETDEWEB)

Othmen, Zied; Oueslati, Meherzi [Unité Nanomatériaux et Photonique, Faculty of Sciences of Tunis, Tunis El-Manar University, 2092 Tunis (Tunisia); Copie, Olivier; Gemeiner, Pascale; Dkhil, Brahim [Laboratoire Structures, Propriétés et Modélisation des Solides, Centrale Supélec, CNRS-UMR 8580, Université Paris-Saclay (France); Daoudi, Kais [Unité Nanomatériaux et Photonique, Faculty of Sciences of Tunis, Tunis El-Manar University, 2092 Tunis (Tunisia); Department of Applied Physics and Astronomy, College of Sciences, University of Sharjah, P.O. Box 27272, Sharjah (United Arab Emirates); Boudard, Michel [Univ. Grenoble Alpes, LMGP, F-38000 Grenoble (France)

2016-07-07

In cobaltite, the spin states transitions of Co{sup 3+/4+} ions govern the magnetic and electronic conduction properties. These transitions are strain-sensitive and can be varied using external parameters, including temperature, hydrostatic pressure, or chemical stresses through ionic substitutions. In this work, using temperature dependent Raman spectroscopy and X-ray diffraction, the epitaxial strain effects on both structural and vibrational properties of La{sub 0.7} Ba{sub 0.3} CoO{sub 3} (LBCO) cobaltite thin films are investigated. All Raman active phonon modes as well as the structure are found to be strongly affected. Both Raman modes and lattice parameter evolutions show temperature changes correlated with magnetic and electronic transitions properties. Combining Raman spectroscopy and X-ray diffraction appears as a powerful approach to probe the spin transition in thin film cobaltite. Our results provide insight into strong spin-charge-phonon coupling in LBCO thin film. This coupling manifests as vibrational transition with temperature in the Raman spectra near the ferromagnetic spin ordered transition at 220 K.

Rates of E1, E2, M1, and M2 transitions in Ni II

Science.gov (United States)

Cassidy, C. M.; Hibbert, A.; Ramsbottom, C. A.

2016-03-01

Aims: We present rates for all E1, E2, M1, and M2 transitions among the 295 fine-structure levels of the configurations 3d9, 3d84s, 3d74s2, 3d84p, and 3d74s4p, determined through an extensive configuration interaction calculation. Methods: The CIV3 code developed by Hibbert and coworkers is used to determine for these levels configuration interaction wave functions with relativistic effects introduced through the Breit-Pauli approximation. Results: Two different sets of calculations have been undertaken with different 3d and 4d functions to ascertain the effect of such variation. The main body of the text includes a representative selection of data, chosen so that key points can be discussed. Some analysis to assess the accuracy of the present data has been undertaken, including comparison with earlier calculations and the more limited range of experimental determinations. The full set of transition data is given in the supplementary material as it is very extensive. Conclusions: We believe that the present transition data are the best currently available. Full Table 4 and Tables 5-8 are only available at the CDS via anonymous ftp to http://cdsarc.u-strasbg.fr (ftp://130.79.128.5) or via http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/587/A107

A/E/C CAD Standard, Release 5.0

Science.gov (United States)

2012-12-01

DMPR Dampers 0 0.35 22 22 X X Graphic Defaults Model File Types CO2 Sprinkler System Aqueous Film Forming Foam System Means of Egress Lighting...45 X E-POWR- GENR Generators and auxiliary equipment 0 0.50 4 7 X E-POWR-JBOX Junction boxes, pull boxes, manholes, handholes, pedestals, splices 0

The B(E2;4^+1->2^+1) / B(E2;2^+1->0^+1) Ratio in Even-Even Nuclei

Science.gov (United States)

Loelius, C.; Sharon, Y. Y.; Zamick, L.; G"Urdal, G.

2009-10-01

We considered 207 even-even nuclei throughout the chart of nuclides for which the NNDC Tables had data on the energies and lifetimes of the 2^+1 and 4^+1 states. Using these data we calculated for each nucleus the electric quadrupole transition strengths B(E2;4^+1->2^+1) and B(E2;2^+1->0^+1), as well as their ratio. The internal conversion coefficients were obtained by using the NNDC HSICC calculator. For each nucleus we plotted the B(E2) ratio against A, N, and Z. We found that for close to 90% of the nuclei considered the ratio had values between 0.5 and 2.5. Most of the outliers had magic numbers of protons or neutrons. Our ratio results were compared with the theoretical predictions for this ratio by different models--10/7 in the rotational model and 2 in the simplest vibrational model. In the rotational regions (for 150 220) the ratios were indeed close to 10/7. For the few nuclei thought to be vibrational the ratios were usually less than 2. Otherwise, we got a wide scatter of ratio values. Hence other models, including the NpNn scheme, must be considered in interpreting these results.

Crystal growth of Sm0.3Tb0.7FeO3 and spin reorientation transition in Sm1−xTbxFeO3 orthoferrite

International Nuclear Information System (INIS)

Wu, Anhua; Wang, Bo; Zhao, Xiangyang; Xie, Tao; Man, Peiwen; Su, Liangbi; Kalashnikova, A.M.; Pisarev, R.V.

2017-01-01

In this work, Sm 0.3 Tb 0.7 FeO 3 single crystal was successfully grown by optical floating zone method. Sm 0.3 Tb 0.7 FeO 3 samples with a-, b-, and c-orientation were manufactured by means of Laue photograph. Magnetic properties of Sm 0.3 Tb 0.7 FeO 3 single crystals are studied over a wide temperature range from 2 to 400 K. Spin reorientation transition from Γ 2 to Γ 4 are observed by means of the temperature dependence of magnetization It indicated the reorientation transition temperature of Sm 1−x Tb x FeO 3 single crystals is lowered with the contents of Tb contents rising based on this work and our previous works, thus the spin reorientation transition temperature can be adjusted through changing the compound in orthoferrites materials, which means that we can get orthoferrites single crystals with high magnetism property in various temperature through material design. - Highlights: • Sm 0.3 Tb 0.7 FeO 3 single crystals with various compounds were successfully grown by optical floating zone method. • The relation between SRT temperature and composition in Sm 1−x Tb x FeO 3 orthoferrite was indicated. • The spin reorientation transition temperature of Sm 1−x Tb x FeO 3 single crystals can be adjusted through changing the compound in orthoferrites materials.

Search for CPT violation in the neutral kaon system and a high sensitivity search for K/sub L/ → π0e+e-: Progress report, August 1, 1988--March 31, 1989

International Nuclear Information System (INIS)

Wah, Yau W.

1988-12-01

Fermilab experiment E-773 with the goal of measuring the phase difference between /phi/ 00 and /phi/ +- to better than . 5 0 is scheduled to run at March 1990 for two months. This precision measurement will improve the world limit by more than an order of magnitude. A letter of intent (P-799) with the goal of searching for the rare decay mode K/sub L/ → π 0 e + e - with a sensitivity of -11 was submitted to Fermilab in October 1988. The formal proposal will be submitted in January 1989. The world best limit B.R.(K/sub L/ → π 0 e + e - -8 ) which came from the E-731 data was published recently by the same group. There are two equipment construction projects currently being carried out; the track-processor and the transition radiation detector. Both are discussed in this paper

Search for the lepton-flavor-violating decays B(s)0→e(±)μ(∓) and B0→e(±)μ(∓).

Science.gov (United States)

Aaij, R; Adeva, B; Adinolfi, M; Adrover, C; Affolder, A; Ajaltouni, Z; Albrecht, J; Alessio, F; Alexander, M; Ali, S; Alkhazov, G; Alvarez Cartelle, P; Alves, A A; Amato, S; Amerio, S; Amhis, Y; Anderlini, L; Anderson, J; Andreassen, R; Andrews, J E; Appleby, R B; Aquines Gutierrez, O; Archilli, F; Artamonov, A; Artuso, M; Aslanides, E; Auriemma, G; Baalouch, M; Bachmann, S; Back, J J; Baesso, C; Balagura, V; Baldini, W; Barlow, R J; Barschel, C; Barsuk, S; Barter, W; Bauer, Th; Bay, A; Beddow, J; Bedeschi, F; Bediaga, I; Belogurov, S; Belous, K; Belyaev, I; Ben-Haim, E; Bencivenni, G; Benson, S; Benton, J; Berezhnoy, A; Bernet, R; Bettler, M-O; van Beuzekom, M; Bien, A; Bifani, S; Bird, T; Bizzeti, A; Bjørnstad, P M; Blake, T; Blanc, F; Blouw, J; Blusk, S; Bocci, V; Bondar, A; Bondar, N; Bonivento, W; Borghi, S; Borgia, A; Bowcock, T J V; Bowen, E; Bozzi, C; Brambach, T; van den Brand, J; Bressieux, J; Brett, D; Britsch, M; Britton, T; Brook, N H; Brown, H; Burducea, I; Bursche, A; Busetto, G; Buytaert, J; Cadeddu, S; Callot, O; Calvi, M; Calvo Gomez, M; Camboni, A; Campana, P; Campora Perez, D; Carbone, A; Carboni, G; Cardinale, R; Cardini, A; Carranza-Mejia, H; Carson, L; Carvalho Akiba, K; Casse, G; Castillo Garcia, L; Cattaneo, M; Cauet, Ch; Cenci, R; Charles, M; Charpentier, Ph; Chen, P; Chiapolini, N; Chrzaszcz, M; Ciba, K; Cid Vidal, X; Ciezarek, G; Clarke, P E L; Clemencic, M; Cliff, H V; Closier, J; Coca, C; Coco, V; Cogan, J; Cogneras, E; Collins, P; Comerma-Montells, A; Contu, A; Cook, A; Coombes, M; Coquereau, S; Corti, G; Couturier, B; Cowan, G A; Craik, D C; Cunliffe, S; Currie, R; D'Ambrosio, C; David, P; David, P N Y; Davis, A; De Bonis, I; De Bruyn, K; De Capua, S; De Cian, M; De Miranda, J M; De Paula, L; De Silva, W; De Simone, P; Decamp, D; Deckenhoff, M; Del Buono, L; Déléage, N; Derkach, D; Deschamps, O; Dettori, F; Di Canto, A; Dijkstra, H; Dogaru, M; Donleavy, S; Dordei, F; Dosil Suárez, A; Dossett, D; Dovbnya, A; Dupertuis, F; Durante, P; Dzhelyadin, R; Dziurda, A; Dzyuba, A; Easo, S; Egede, U; Egorychev, V; Eidelman, S; van Eijk, D; Eisenhardt, S; Eitschberger, U; Ekelhof, R; Eklund, L; El Rifai, I; Elsasser, Ch; Falabella, A; Färber, C; Fardell, G; Farinelli, C; Farry, S; Fave, V; Ferguson, D; Fernandez Albor, V; Ferreira Rodrigues, F; Ferro-Luzzi, M; Filippov, S; Fiore, M; Fitzpatrick, C; Fontana, M; Fontanelli, F; Forty, R; Francisco, O; Frank, M; Frei, C; Frosini, M; Furcas, S; Furfaro, E; Gallas Torreira, A; Galli, D; Gandelman, M; Gandini, P; Gao, Y; Garofoli, J; Garosi, P; Garra Tico, J; Garrido, L; Gaspar, C; Gauld, R; Gersabeck, E; Gersabeck, M; Gershon, T; Ghez, Ph; Gibson, V; Giubega, L; Gligorov, V V; Göbel, C; Golubkov, D; Golutvin, A; Gomes, A; Gordon, H; Grabalosa Gándara, M; Graciani Diaz, R; Granado Cardoso, L A; Graugés, E; Graziani, G; Grecu, A; Greening, E; Gregson, S; Griffith, P; Grünberg, O; Gui, B; Gushchin, E; Guz, Yu; Gys, T; Hadjivasiliou, C; Haefeli, G; Haen, C; Haines, S C; Hall, S; Hamilton, B; Hampson, T; Hansmann-Menzemer, S; Harnew, N; Harnew, S T; Harrison, J; Hartmann, T; He, J; Head, T; Heijne, V; Hennessy, K; Henrard, P; Hernando Morata, J A; van Herwijnen, E; Hicheur, A; Hicks, E; Hill, D; Hoballah, M; Hombach, C; Hopchev, P; Hulsbergen, W; Hunt, P; Huse, T; Hussain, N; Hutchcroft, D; Hynds, D; Iakovenko, V; Idzik, M; Ilten, P; Jacobsson, R; Jaeger, A; Jans, E; Jaton, P; Jawahery, A; Jing, F; John, M; Johnson, D; Jones, C R; Joram, C; Jost, B; Kaballo, M; Kandybei, S; Kanso, W; Karacson, M; Karbach, T M; Kenyon, I R; Ketel, T; Keune, A; Khanji, B; Kochebina, O; Komarov, I; Koopman, R F; Koppenburg, P; Korolev, M; Kozlinskiy, A; Kravchuk, L; Kreplin, K; Kreps, M; Krocker, G; Krokovny, P; Kruse, F; Kucharczyk, M; Kudryavtsev, V; Kvaratskheliya, T; La Thi, V N; Lacarrere, D; Lafferty, G; Lai, A; Lambert, D; Lambert, R W; Lanciotti, E; Lanfranchi, G; Langenbruch, C; Latham, T; Lazzeroni, C; Le Gac, R; van Leerdam, J; Lees, J-P; Lefèvre, R; Leflat, A; Lefrançois, J; Leo, S; Leroy, O; Lesiak, T; Leverington, B; Li, Y; Li Gioi, L; Liles, M; Lindner, R; Linn, C; Liu, B; Liu, G; Lohn, S; Longstaff, I; Lopes, J H; Lopez-March, N; Lu, H; Lucchesi, D; Luisier, J; Luo, H; Machefert, F; Machikhiliyan, I V; Maciuc, F; Maev, O; Malde, S; Manca, G; Mancinelli, G; Maratas, J; Marconi, U; Marino, P; Märki, R; Marks, J; Martellotti, G; Martens, A; Martín Sánchez, A; Martinelli, M; Martinez Santos, D; Martins Tostes, D; Massafferri, A; Matev, R; Mathe, Z; Matteuzzi, C; Maurice, E; Mazurov, A; McSkelly, B; McCarthy, J; McNab, A; McNulty, R; Meadows, B; Meier, F; Meissner, M; Merk, M; Milanes, D A; Minard, M-N; Molina Rodriguez, J; Monteil, S; Moran, D; Morawski, P; Mordà, A; Morello, M J; Mountain, R; Mous, I; Muheim, F; Müller, K; Muresan, R; Muryn, B; Muster, B; Naik, P; Nakada, T; Nandakumar, R; Nasteva, I; Needham, M; Neubert, S; Neufeld, N; Nguyen, A D; Nguyen, T D; Nguyen-Mau, C; Nicol, M; Niess, V; Niet, R; Nikitin, N; Nikodem, T; Nomerotski, A; Novoselov, A; Oblakowska-Mucha, A; Obraztsov, V; Oggero, S; Ogilvy, S; Okhrimenko, O; Oldeman, R; Orlandea, M; Otalora Goicochea, J M; Owen, P; Oyanguren, A; Pal, B K; Palano, A; Palutan, M; Panman, J; Papanestis, A; Pappagallo, M; Parkes, C; Parkinson, C J; Passaleva, G; Patel, G D; Patel, M; Patrick, G N; Patrignani, C; Pavel-Nicorescu, C; Pazos Alvarez, A; Pellegrino, A; Penso, G; Pepe Altarelli, M; Perazzini, S; Perez Trigo, E; Pérez-Calero Yzquierdo, A; Perret, P; Perrin-Terrin, M; Pescatore, L; Pessina, G; Petridis, K; Petrolini, A; Phan, A; Picatoste Olloqui, E; Pietrzyk, B; Pilař, T; Pinci, D; Playfer, S; Plo Casasus, M; Polci, F; Polok, G; Poluektov, A; Polycarpo, E; Popov, A; Popov, D; Popovici, B; Potterat, C; Powell, A; Prisciandaro, J; Pritchard, A; Prouve, C; Pugatch, V; Puig Navarro, A; Punzi, G; Qian, W; Rademacker, J H; Rakotomiaramanana, B; Rangel, M S; Raniuk, I; Rauschmayr, N; Raven, G; Redford, S; Reid, M M; dos Reis, A C; Ricciardi, S; Richards, A; Rinnert, K; Rives Molina, V; Roa Romero, D A; Robbe, P; Roberts, D A; Rodrigues, E; Rodriguez Perez, P; Roiser, S; Romanovsky, V; Romero Vidal, A; Rouvinet, J; Ruf, T; Ruffini, F; Ruiz, H; Ruiz Valls, P; Sabatino, G; Saborido Silva, J J; Sagidova, N; Sail, P; Saitta, B; Salustino Guimaraes, V; Salzmann, C; Sanmartin Sedes, B; Sannino, M; Santacesaria, R; Santamarina Rios, C; Santovetti, E; Sapunov, M; Sarti, A; Satriano, C; Satta, A; Savrie, M; Savrina, D; Schaack, P; Schiller, M; Schindler, H; Schlupp, M; Schmelling, M; Schmidt, B; Schneider, O; Schopper, A; Schune, M-H; Schwemmer, R; Sciascia, B; Sciubba, A; Seco, M; Semennikov, A; Senderowska, K; Sepp, I; Serra, N; Serrano, J; Seyfert, P; Shapkin, M; Shapoval, I; Shatalov, P; Shcheglov, Y; Shears, T; Shekhtman, L; Shevchenko, O; Shevchenko, V; Shires, A; Silva Coutinho, R; Sirendi, M; Skwarnicki, T; Smith, N A; Smith, E; Smith, J; Smith, M; Sokoloff, M D; Soler, F J P; Soomro, F; Souza, D; Souza De Paula, B; Spaan, B; Sparkes, A; Spradlin, P; Stagni, F; Stahl, S; Steinkamp, O; Stevenson, S; Stoica, S; Stone, S; Storaci, B; Straticiuc, M; Straumann, U; Subbiah, V K; Sun, L; Swientek, S; Syropoulos, V; Szczekowski, M; Szczypka, P; Szumlak, T; T'Jampens, S; Teklishyn, M; Teodorescu, E; Teubert, F; Thomas, C; Thomas, E; van Tilburg, J; Tisserand, V; Tobin, M; Tolk, S; Tonelli, D; Topp-Joergensen, S; Torr, N; Tournefier, E; Tourneur, S; Tran, M T; Tresch, M; Tsaregorodtsev, A; Tsopelas, P; Tuning, N; Ubeda Garcia, M; Ukleja, A; Urner, D; Ustyuzhanin, A; Uwer, U; Vagnoni, V; Valenti, G; Vallier, A; Van Dijk, M; Vazquez Gomez, R; Vazquez Regueiro, P; Vázquez Sierra, C; Vecchi, S; Velthuis, J J; Veltri, M; Veneziano, G; Vesterinen, M; Viaud, B; Vieira, D; Vilasis-Cardona, X; Vollhardt, A; Volyanskyy, D; Voong, D; Vorobyev, A; Vorobyev, V; Voß, C; Voss, H; Waldi, R; Wallace, C; Wallace, R; Wandernoth, S; Wang, J; Ward, D R; Watson, N K; Webber, A D; Websdale, D; Whitehead, M; Wicht, J; Wiechczynski, J; Wiedner, D; Wiggers, L; Wilkinson, G; Williams, M P; Williams, M; Wilson, F F; Wimberley, J; Wishahi, J; Witek, M; Wotton, S A; Wright, S; Wu, S; Wyllie, K; Xie, Y; Xing, Z; Yang, Z; Young, R; Yuan, X; Yushchenko, O; Zangoli, M; Zavertyaev, M; Zhang, F; Zhang, L; Zhang, W C; Zhang, Y; Zhelezov, A; Zhokhov, A; Zhong, L; Zvyagin, A

2013-10-04

A search for the lepton-flavor-violating decays B(s)0→e(±)μ(∓) and B0→e(±)μ(∓) is performed with a data sample, corresponding to an integrated luminosity of 1.0 fb(-1) of pp collisions at √s=7 TeV, collected by the LHCb experiment. The observed number of B(s)0→e(±)μ(∓) and B0→e(±)μ(∓) candidates is consistent with background expectations. Upper limits on the branching fractions of both decays are determined to be B(B(s)0→e(±)μ(∓))M(LQ)(B(s)0→e(±)μ(∓))>101 TeV/c(2) and M(LQ)(B0→e(±)μ(∓))>126 TeV/c(2) at 95% C.L., and are a factor of 2 higher than the previous bounds.

Web 2.0 in e-Learning

Directory of Open Access Journals (Sweden)

M. Tariq Banday

2013-10-01

Full Text Available Web 2.0 tools have created fresh opportunities for governments, education, businesses and individuals to enhance efficiency and improve effectiveness while executing respective professional duties. The key features of these tools include online character and access through a web browser, supportive for open content licenses, open sharing and social interaction, and often free to use or support free features. These have created novel prospects for teachers to combine face-to-face teaching and online materials via social media such as discussion forums, blogs and wikis. The web 2.0 educational design is based on socio-cultural learning theories such as interaction, joint creation of content, critical thinking, learning by doing and collaboration. This paper makes an appraisal of ICT adoption in education, emergence of Web, improvements in Web and its effect on the e-Learning. It explains gradual integration of ICT into education through various stages. The paper presents the content and communication dimensions of e-learning for its classification. It discusses various opportunities created by Web 2.0 tools in education for effective teacher-learner, learner-learner and teacher-teacher communication, interaction and collaboration. It presents various cases and projects involving use of some Web 2.0 tools for enhancing learning. Furthermore, it lists some challenges for successful implementation of e-learning through Web 2.0 tools and discusses some possible solutions for its control.

Topic 2.0: Tropical cyclone formation and extratropical transition

OpenAIRE

Harr, Patrick A.

2010-01-01

Approved for public release; distribution is unlimited In this section, progress since ITWC-VI on research, observations and forecasting of tropical cyclone formation and extratropical transition is summarized. While tropical cyclone formation and extratropical transition are stages at opposite ends of the tropical cyclone lifecycle, significant lack of understanding remains in relation to processes associated with each stage. Formation and extratropical transition involve interactions a...

ACCURATE LABORATORY WAVELENGTHS OF THE e 3 Σ-(ν' = 5) - X 1 Σ+(ν'' = 0) BAND OF 12C16O

International Nuclear Information System (INIS)

Dickenson, G. D.; Nortje, A. C.; Steenkamp, C. M.; Rohwer, E. G.; Du Plessis, A.

2010-01-01

The forbidden singlet-triplet transitions of carbon monoxide (CO) are important in the interpretation of vacuum ultraviolet interstellar absorption spectra and in particular for the measurement of large CO column densities. Twenty rovibronic lines of the e 3 Σ - (ν' = 5) - X 1 Σ + (ν'' = 0) band of 12 C 16 O for which laboratory wavelengths were previously unavailable were identified in laser-induced fluorescence excitation spectra. Wavelengths were assigned to five rovibronic transitions to an average accuracy of 0.0028 A. A further 15 lines could not be fully resolved and average wavelengths were measured for these groups of closely spaced lines. A wavelength difference of 0.011 ± 0.0028 A between the measured wavelengths and the calculated wavelengths in the atlas of Eidelsberg and Rostas demonstrates the need for more experimental data on CO.

Accurate Laboratory Wavelengths of the e 3 Σ-(ν' = 5) - X 1 Σ+(ν'' = 0) Band of 12C16O

Science.gov (United States)

Dickenson, G. D.; Nortje, A. C.; Steenkamp, C. M.; Rohwer, E. G.; Du Plessis, A.

2010-05-01

The forbidden singlet-triplet transitions of carbon monoxide (CO) are important in the interpretation of vacuum ultraviolet interstellar absorption spectra and in particular for the measurement of large CO column densities. Twenty rovibronic lines of the e 3Σ-(ν' = 5) - X 1Σ+(ν'' = 0) band of 12 C 16O for which laboratory wavelengths were previously unavailable were identified in laser-induced fluorescence excitation spectra. Wavelengths were assigned to five rovibronic transitions to an average accuracy of 0.0028 Å. A further 15 lines could not be fully resolved and average wavelengths were measured for these groups of closely spaced lines. A wavelength difference of 0.011 ± 0.0028 Å between the measured wavelengths and the calculated wavelengths in the atlas of Eidelsberg & Rostas demonstrates the need for more experimental data on CO.

Ge(001)-(<2 1>, <0 3>)-Pb(<2 1>, <0 6>)↔Pb: Low-temperature two-dimensional phase transition

DEFF Research Database (Denmark)

Bunk, Oliver; Nielsen, Martin Meedom; Zeysing, J.H.

2001-01-01

The Ge(001)-((2 1)(0 3))-Pb surface reconstruction with a lead coverage of 5/3 monolayer is on the borderline between the low-coverage covalently-bonded and high-coverage metallic lead overlayers. This gives rise to an unusual low-temperature phase transition with concomitant changes in the bonding...

Angular analysis of the $B^0 \\rightarrow K^{*0} e^+ e^-$ decay in the low-$q^2$ region

CERN Document Server

Aaij, Roel; Adinolfi, Marco; Affolder, Anthony; Ajaltouni, Ziad; Akar, Simon; Albrecht, Johannes; Alessio, Federico; Alexander, Michael; Ali, Suvayu; Alkhazov, Georgy; Alvarez Cartelle, Paula; Alves Jr, Antonio Augusto; Amato, Sandra; Amerio, Silvia; Amhis, Yasmine; An, Liupan; Anderlini, Lucio; Anderson, Jonathan; Andreassen, Rolf; Andreotti, Mirco; Andrews, Jason; Appleby, Robert; Aquines Gutierrez, Osvaldo; Archilli, Flavio; Artamonov, Alexander; Artuso, Marina; Aslanides, Elie; Auriemma, Giulio; Baalouch, Marouen; Bachmann, Sebastian; Back, John; Badalov, Alexey; Baesso, Clarissa; Baldini, Wander; Barlow, Roger; Barschel, Colin; Barsuk, Sergey; Barter, William; Batozskaya, Varvara; Battista, Vincenzo; Bay, Aurelio; Beaucourt, Leo; Beddow, John; Bedeschi, Franco; Bediaga, Ignacio; Belogurov, Sergey; Belyaev, Ivan; Ben-Haim, Eli; Bencivenni, Giovanni; Benson, Sean; Benton, Jack; Berezhnoy, Alexander; Bernet, Roland; Bertolin, Alessandro; Bettler, Marc-Olivier; van Beuzekom, Martinus; Bien, Alexander; Bifani, Simone; Bird, Thomas; Bizzeti, Andrea; Blake, Thomas; Blanc, Frédéric; Blouw, Johan; Blusk, Steven; Bocci, Valerio; Bondar, Alexander; Bondar, Nikolay; Bonivento, Walter; Borghi, Silvia; Borgia, Alessandra; Borsato, Martino; Bowcock, Themistocles; Bowen, Espen Eie; Bozzi, Concezio; Brett, David; Britsch, Markward; Britton, Thomas; Brodzicka, Jolanta; Brook, Nicholas; Bursche, Albert; Buytaert, Jan; Cadeddu, Sandro; Calabrese, Roberto; Calvi, Marta; Calvo Gomez, Miriam; Campana, Pierluigi; Campora Perez, Daniel; Capriotti, Lorenzo; Carbone, Angelo; Carboni, Giovanni; Cardinale, Roberta; Cardini, Alessandro; Carson, Laurence; Carvalho Akiba, Kazuyoshi; Casanova Mohr, Raimon; Casse, Gianluigi; Cassina, Lorenzo; Castillo Garcia, Lucia; Cattaneo, Marco; Cauet, Christophe; Cenci, Riccardo; Charles, Matthew; Charpentier, Philippe; Chefdeville, Maximilien; Chen, Shanzhen; Cheung, Shu-Faye; Chiapolini, Nicola; Chrzaszcz, Marcin; Cid Vidal, Xabier; Ciezarek, Gregory; Clarke, Peter; Clemencic, Marco; Cliff, Harry; Closier, Joel; Coco, Victor; Cogan, Julien; Cogneras, Eric; Cogoni, Violetta; Cojocariu, Lucian; Collazuol, Gianmaria; Collins, Paula; Comerma-Montells, Albert; Contu, Andrea; Cook, Andrew; Coombes, Matthew; Coquereau, Samuel; Corti, Gloria; Corvo, Marco; Counts, Ian; Couturier, Benjamin; Cowan, Greig; Craik, Daniel Charles; Crocombe, Andrew Christopher; Cruz Torres, Melissa Maria; Cunliffe, Samuel; Currie, Robert; D'Ambrosio, Carmelo; Dalseno, Jeremy; David, Pascal; David, Pieter; Davis, Adam; De Bruyn, Kristof; De Capua, Stefano; De Cian, Michel; De Miranda, Jussara; De Paula, Leandro; De Silva, Weeraddana; De Simone, Patrizia; Dean, Cameron Thomas; Decamp, Daniel; Deckenhoff, Mirko; Del Buono, Luigi; Déléage, Nicolas; Derkach, Denis; Deschamps, Olivier; Dettori, Francesco; Dey, Biplab; Di Canto, Angelo; Di Domenico, Antonio; Di Ruscio, Francesco; Dijkstra, Hans; Donleavy, Stephanie; Dordei, Francesca; Dorigo, Mirco; Dosil Suárez, Alvaro; Dossett, David; Dovbnya, Anatoliy; Dreimanis, Karlis; Dujany, Giulio; Dupertuis, Frederic; Durante, Paolo; Dzhelyadin, Rustem; Dziurda, Agnieszka; Dzyuba, Alexey; Easo, Sajan; Egede, Ulrik; Egorychev, Victor; Eidelman, Semen; Eisenhardt, Stephan; Eitschberger, Ulrich; Ekelhof, Robert; Eklund, Lars; El Rifai, Ibrahim; Elsasser, Christian; Ely, Scott; Esen, Sevda; Evans, Hannah Mary; Evans, Timothy; Falabella, Antonio; Färber, Christian; Farinelli, Chiara; Farley, Nathanael; Farry, Stephen; Fay, Robert; Ferguson, Dianne; Fernandez Albor, Victor; Ferreira Rodrigues, Fernando; Ferro-Luzzi, Massimiliano; Filippov, Sergey; Fiore, Marco; Fiorini, Massimiliano; Firlej, Miroslaw; Fitzpatrick, Conor; Fiutowski, Tomasz; Fol, Philip; Fontana, Marianna; Fontanelli, Flavio; Forty, Roger; Francisco, Oscar; Frank, Markus; Frei, Christoph; Frosini, Maddalena; Fu, Jinlin; Furfaro, Emiliano; Gallas Torreira, Abraham; Galli, Domenico; Gallorini, Stefano; Gambetta, Silvia; Gandelman, Miriam; Gandini, Paolo; Gao, Yuanning; García Pardiñas, Julián; Garofoli, Justin; Garra Tico, Jordi; Garrido, Lluis; Gascon, David; Gaspar, Clara; Gastaldi, Ugo; Gauld, Rhorry; Gavardi, Laura; Gazzoni, Giulio; Geraci, Angelo; Gersabeck, Evelina; Gersabeck, Marco; Gershon, Timothy; Ghez, Philippe; Gianelle, Alessio; Gianì, Sebastiana; Gibson, Valerie; Giubega, Lavinia-Helena; Gligorov, V.V.; Göbel, Carla; Golubkov, Dmitry; Golutvin, Andrey; Gomes, Alvaro; Gotti, Claudio; Grabalosa Gándara, Marc; Graciani Diaz, Ricardo; Granado Cardoso, Luis Alberto; Graugés, Eugeni; Graverini, Elena; Graziani, Giacomo; Grecu, Alexandru; Greening, Edward; Gregson, Sam; Griffith, Peter; Grillo, Lucia; Grünberg, Oliver; Gui, Bin; Gushchin, Evgeny; Guz, Yury; Gys, Thierry; Hadjivasiliou, Christos; Haefeli, Guido; Haen, Christophe; Haines, Susan; Hall, Samuel; Hamilton, Brian; Hampson, Thomas; Han, Xiaoxue; Hansmann-Menzemer, Stephanie; Harnew, Neville; Harnew, Samuel; Harrison, Jonathan; He, Jibo; Head, Timothy; Heijne, Veerle; Hennessy, Karol; Henrard, Pierre; Henry, Louis; Hernando Morata, Jose Angel; van Herwijnen, Eric; Heß, Miriam; Hicheur, Adlène; Hill, Donal; Hoballah, Mostafa; Hombach, Christoph; Hulsbergen, Wouter; Hussain, Nazim; Hutchcroft, David; Hynds, Daniel; Idzik, Marek; Ilten, Philip; Jacobsson, Richard; Jaeger, Andreas; Jalocha, Pawel; Jans, Eddy; Jawahery, Abolhassan; Jing, Fanfan; John, Malcolm; Johnson, Daniel; Jones, Christopher; Joram, Christian; Jost, Beat; Jurik, Nathan; Kandybei, Sergii; Kanso, Walaa; Karacson, Matthias; Karbach, Moritz; Karodia, Sarah; Kelsey, Matthew; Kenyon, Ian; Kenzie, Matthew; Ketel, Tjeerd; Khanji, Basem; Khurewathanakul, Chitsanu; Klaver, Suzanne; Klimaszewski, Konrad; Kochebina, Olga; Kolpin, Michael; Komarov, Ilya; Koopman, Rose; Koppenburg, Patrick; Korolev, Mikhail; Kravchuk, Leonid; Kreplin, Katharina; Kreps, Michal; Krocker, Georg; Krokovny, Pavel; Kruse, Florian; Kucewicz, Wojciech; Kucharczyk, Marcin; Kudryavtsev, Vasily; Kurek, Krzysztof; Kvaratskheliya, Tengiz; La Thi, Viet Nga; Lacarrere, Daniel; Lafferty, George; Lai, Adriano; Lambert, Dean; Lambert, Robert W; Lanfranchi, Gaia; Langenbruch, Christoph; Langhans, Benedikt; Latham, Thomas; Lazzeroni, Cristina; Le Gac, Renaud; van Leerdam, Jeroen; Lees, Jean-Pierre; Lefèvre, Regis; Leflat, Alexander; Lefrançois, Jacques; Leroy, Olivier; Lesiak, Tadeusz; Leverington, Blake; Li, Yiming; Likhomanenko, Tatiana; Liles, Myfanwy; Lindner, Rolf; Linn, Christian; Lionetto, Federica; Liu, Bo; Lohn, Stefan; Longstaff, Iain; Lopes, Jose; Lowdon, Peter; Lucchesi, Donatella; Luo, Haofei; Lupato, Anna; Luppi, Eleonora; Lupton, Oliver; Machefert, Frederic; Machikhiliyan, Irina V; Maciuc, Florin; Maev, Oleg; Malde, Sneha; Malinin, Alexander; Manca, Giulia; Mancinelli, Giampiero; Manning, Peter Michael; Mapelli, Alessandro; Maratas, Jan; Marchand, Jean François; Marconi, Umberto; Marin Benito, Carla; Marino, Pietro; Märki, Raphael; Marks, Jörg; Martellotti, Giuseppe; Martinelli, Maurizio; Martinez Santos, Diego; Martinez Vidal, Fernando; Martins Tostes, Danielle; Massafferri, André; Matev, Rosen; Mathe, Zoltan; Matteuzzi, Clara; Maurin, Brice; Mazurov, Alexander; McCann, Michael; McCarthy, James; McNab, Andrew; McNulty, Ronan; McSkelly, Ben; Meadows, Brian; Meier, Frank; Meissner, Marco; Merk, Marcel; Milanes, Diego Alejandro; Minard, Marie-Noelle; Moggi, Niccolò; Molina Rodriguez, Josue; Monteil, Stephane; Morandin, Mauro; Morawski, Piotr; Mordà, Alessandro; Morello, Michael Joseph; Moron, Jakub; Morris, Adam Benjamin; Mountain, Raymond; Muheim, Franz; Müller, Katharina; Mussini, Manuel; Muster, Bastien; Naik, Paras; Nakada, Tatsuya; Nandakumar, Raja; Nasteva, Irina; Needham, Matthew; Neri, Nicola; Neubert, Sebastian; Neufeld, Niko; Neuner, Max; Nguyen, Anh Duc; Nguyen, Thi-Dung; Nguyen-Mau, Chung; Nicol, Michelle; Niess, Valentin; Niet, Ramon; Nikitin, Nikolay; Nikodem, Thomas; Novoselov, Alexey; O'Hanlon, Daniel Patrick; Oblakowska-Mucha, Agnieszka; Obraztsov, Vladimir; Ogilvy, Stephen; Okhrimenko, Oleksandr; Oldeman, Rudolf; Onderwater, Gerco; Orlandea, Marius; Osorio Rodrigues, Bruno; Otalora Goicochea, Juan Martin; Otto, Adam; Owen, Patrick; Oyanguren, Maria Arantza; Pal, Bilas Kanti; Palano, Antimo; Palombo, Fernando; Palutan, Matteo; Panman, Jacob; Papanestis, Antonios; Pappagallo, Marco; Pappalardo, Luciano; Parkes, Christopher; Parkinson, Christopher John; Passaleva, Giovanni; Patel, Girish; Patel, Mitesh; Patrignani, Claudia; Pearce, Alex; Pellegrino, Antonio; Penso, Gianni; Pepe Altarelli, Monica; Perazzini, Stefano; Perret, Pascal; Pescatore, Luca; Pesen, Erhan; Petridis, Konstantin; Petrolini, Alessandro; Picatoste Olloqui, Eduardo; Pietrzyk, Boleslaw; Pilař, Tomas; Pinci, Davide; Pistone, Alessandro; Playfer, Stephen; Plo Casasus, Maximo; Polci, Francesco; Poluektov, Anton; Polyakov, Ivan; Polycarpo, Erica; Popov, Alexander; Popov, Dmitry; Popovici, Bogdan; Potterat, Cédric; Price, Eugenia; Price, Joseph David; Prisciandaro, Jessica; Pritchard, Adrian; Prouve, Claire; Pugatch, Valery; Puig Navarro, Albert; Punzi, Giovanni; Qian, Wenbin; Quagliani, Renato; Rachwal, Bartolomiej; Rademacker, Jonas; Rakotomiaramanana, Barinjaka; Rama, Matteo; Rangel, Murilo; Raniuk, Iurii; Rauschmayr, Nathalie; Raven, Gerhard; Redi, Federico; Reichert, Stefanie; Reid, Matthew; dos Reis, Alberto; Ricciardi, Stefania; Richards, Sophie; Rihl, Mariana; Rinnert, Kurt; Rives Molina, Vincente; Robbe, Patrick; Rodrigues, Ana Barbara; Rodrigues, Eduardo; Rodriguez Perez, Pablo; Roiser, Stefan; Romanovsky, Vladimir; Romero Vidal, Antonio; Rotondo, Marcello; Rouvinet, Julien; Ruf, Thomas; Ruiz, Hugo; Ruiz Valls, Pablo; Saborido Silva, Juan Jose; Sagidova, Naylya; Sail, Paul; Saitta, Biagio; Salustino Guimaraes, Valdir; Sanchez Mayordomo, Carlos; Sanmartin Sedes, Brais; Santacesaria, Roberta; Santamarina Rios, Cibran; Santovetti, Emanuele; Sarti, Alessio; Satriano, Celestina; Satta, Alessia; Saunders, Daniel Martin; Savrina, Darya; Schiller, Manuel; Schindler, Heinrich; Schlupp, Maximilian; Schmelling, Michael; Schmidt, Burkhard; Schneider, Olivier; Schopper, Andreas; Schune, Marie Helene; Schwemmer, Rainer; Sciascia, Barbara; Sciubba, Adalberto; Semennikov, Alexander; Sepp, Indrek; Serra, Nicola; Serrano, Justine; Sestini, Lorenzo; Seyfert, Paul; Shapkin, Mikhail; Shapoval, Illya; Shcheglov, Yury; Shears, Tara; Shekhtman, Lev; Shevchenko, Vladimir; Shires, Alexander; Silva Coutinho, Rafael; Simi, Gabriele; Sirendi, Marek; Skidmore, Nicola; Skillicorn, Ian; Skwarnicki, Tomasz; Smith, Anthony; Smith, Edmund; Smith, Eluned; Smith, Jackson; Smith, Mark; Snoek, Hella; Sokoloff, Michael; Soler, Paul; Soomro, Fatima; Souza, Daniel; Souza De Paula, Bruno; Spaan, Bernhard; Spradlin, Patrick; Sridharan, Srikanth; Stagni, Federico; Stahl, Marian; Stahl, Sascha; Steinkamp, Olaf; Stenyakin, Oleg; Sterpka, Christopher Francis; Stevenson, Scott; Stoica, Sabin; Stone, Sheldon; Storaci, Barbara; Stracka, Simone; Straticiuc, Mihai; Straumann, Ulrich; Stroili, Roberto; Sun, Liang; Sutcliffe, William; Swientek, Krzysztof; Swientek, Stefan; Syropoulos, Vasileios; Szczekowski, Marek; Szczypka, Paul; Szumlak, Tomasz; T'Jampens, Stephane; Teklishyn, Maksym; Tellarini, Giulia; Teubert, Frederic; Thomas, Christopher; Thomas, Eric; van Tilburg, Jeroen; Tisserand, Vincent; Tobin, Mark; Todd, Jacob; Tolk, Siim; Tomassetti, Luca; Tonelli, Diego; Topp-Joergensen, Stig; Torr, Nicholas; Tournefier, Edwige; Tourneur, Stephane; Trabelsi, Karim; Tran, Minh Tâm; Tresch, Marco; Trisovic, Ana; Tsaregorodtsev, Andrei; Tsopelas, Panagiotis; Tuning, Niels; Ubeda Garcia, Mario; Ukleja, Artur; Ustyuzhanin, Andrey; Uwer, Ulrich; Vacca, Claudia; Vagnoni, Vincenzo; Valenti, Giovanni; Vallier, Alexis; Vazquez Gomez, Ricardo; Vazquez Regueiro, Pablo; Vázquez Sierra, Carlos; Vecchi, Stefania; Velthuis, Jaap; Veltri, Michele; Veneziano, Giovanni; Vesterinen, Mika; Viana Barbosa, Joao Vitor; Viaud, Benoit; Vieira, Daniel; Vieites Diaz, Maria; Vilasis-Cardona, Xavier; Vollhardt, Achim; Volyanskyy, Dmytro; Voong, David; Vorobyev, Alexey; Vorobyev, Vitaly; Voß, Christian; de Vries, Jacco; Waldi, Roland; Wallace, Charlotte; Wallace, Ronan; Walsh, John; Wandernoth, Sebastian; Wang, Jianchun; Ward, David; Watson, Nigel; Websdale, David; Whitehead, Mark; Wiedner, Dirk; Wilkinson, Guy; Wilkinson, Michael; Williams, Matthew; Williams, Mike; Wilschut, Hans; Wilson, Fergus; Wimberley, Jack; Wishahi, Julian; Wislicki, Wojciech; Witek, Mariusz; Wormser, Guy; Wotton, Stephen; Wright, Simon; Wyllie, Kenneth; Xie, Yuehong; Xing, Zhou; Xu, Zhirui; Yang, Zhenwei; Yuan, Xuhao; Yushchenko, Oleg; Zangoli, Maria; Zavertyaev, Mikhail; Zhang, Liming; Zhang, Wen Chao; Zhang, Yanxi; Zhelezov, Alexey; Zhokhov, Anatoly; Zhong, Liang

2015-04-14

An angular analysis of the $B^0 \\rightarrow K^{*0} e^+ e^-$ decay is performed using a data sample, corresponding to an integrated luminosity of 3.0 ${\\mbox{fb}^{-1}}$, collected by the LHCb experiment in $pp$ collisions at centre-of-mass energies of 7 and 8 TeV during 2011 and 2012. For the first time several observables are measured in the dielectron mass squared ($q^2$) interval between 0.002 and 1.120${\\mathrm{\\,Ge\\kern -0.1em V^2\\!/}c^4}$. The angular observables $F_{\\mathrm{L}}$ and $A_{\\mathrm{T}}^{\\mathrm{Re}}$ which are related to the $K^{*0}$ polarisation and to the lepton forward-backward asymmetry, are measured to be $F_{\\mathrm{L}}= 0.16 \\pm 0.06 \\pm0.03$ and $A_{\\mathrm{T}}^{\\mathrm{Re}} = 0.10 \\pm 0.18 \\pm 0.05$, where the first uncertainty is statistical and the second systematic. The angular observables $A_{\\mathrm{T}}^{(2)}$ and $A_{\\mathrm{T}}^{\\mathrm{Im}}$ which are sensitive to the photon polarisation in this $q^2$ range, are found to be $A_{\\mathrm{T}}^{(2)} = -0.23 \\pm 0.23 \\pm 0.05$ a...

Infrared reflectivity investigation of the phase transition sequence in Pr{sub 0.5}Ca{sub 0.5}MnO{sub 3}

Energy Technology Data Exchange (ETDEWEB)

Ribeiro, J.L., E-mail: jlr@fisica.uminho.pt [Centro and Departamento de Física da Universidade do Minho, Campus de Gualtar, 4710-057 Braga (Portugal); Vieira, L.G. [Centro and Departamento de Física da Universidade do Minho, Campus de Gualtar, 4710-057 Braga (Portugal); Gomes, I.T. [Centro and Departamento de Física da Universidade do Minho, Campus de Gualtar, 4710-057 Braga (Portugal); IFIMUP and IN - Institute of Nanoscience and Nanotechnology, Departamento de Física e Astronomia da Faculdade de Ciências da Universidade do Porto, R. do Campo Alegre, 687, 4769-007 Porto (Portugal); Araújo, J.P. [IFIMUP and IN - Institute of Nanoscience and Nanotechnology, Departamento de Física e Astronomia da Faculdade de Ciências da Universidade do Porto, R. do Campo Alegre, 687, 4769-007 Porto (Portugal); Tavares, P. [Centro de Química – Vila Real, Universidade de Trás-os-Montes e Alto Douro, 5001-801 Vila Real (Portugal); Almeida, B.G. [Centro and Departamento de Física da Universidade do Minho, Campus de Gualtar, 4710-057 Braga (Portugal)

2016-06-15

This work reports an infrared reflectivity study of the phase transition sequence observed in Pr{sub 0.5}Ca{sub 0.5}MnO{sub 3.} The need to measure over an extended spectral range in order to properly take into account the effects of the high frequency polaronic absorption is circumvented by adopting a simple approximate method, based on the asymmetry present in the Kramers Kronig inversion of the phonon spectrum. The temperature dependence of the phonon optical conductivity is then investigated by monitoring the behavior of three relevant spectral moments of the optical conductivity. This combined methodology allows us to disclose subtle effects of the orbital, charge and magnetic orders on the lattice dynamics of the compound. The characteristic transition temperatures inferred from the spectroscopic measurements are compared and correlated with those obtained from the temperature dependence of the induced magnetization and electrical resistivity. - Highlights: • Study of the effects of orbital, charge and spin orders on the lattice dynamics. • Phonon optical conductivity spectral moments are used to monitor phase transitions. • Precursor effects of the AFM order are detected by infrared spectroscopy.

Generalized oscillator strength for the transition Aapprox. /sup 1/B/sup 2u/Xapprox. A/sub 1g/ in benzene at initial kinetic energies 400 eV and 500 eV

Energy Technology Data Exchange (ETDEWEB)

Klump, K N; Lassettre, E N

1977-10-01

Generalized oscillator strengths, f, for the transition A/sup 1/B/sub 2u/ reverse arrow X/sup 1/A/sub 1g/ in benzene, determined by electron impact methods, are reported as a function of the momentum change. At scattering angles down to 2.5/sup 0/ helium was used as the comparison gas. Determinations are also reported at theta = 0/sup 0/ using mercury as the comparison gas. The oscillator strength curve has both a minimum and a maximum due to the superposition of electric dipole and octupole transitions. The band envelope is studied and is shown to remain unchanged in shape but is shifted by h nu/sub 6/ approximately 0.065 eV with increasing angle due to the shift from electric dipole to octupole scattering.

Infield X-ray diffraction studies of field and temperature driven structural phase transition in Nd{sub 0.49}Sr{sub 0.51}MnO{sub 3+δ}

Energy Technology Data Exchange (ETDEWEB)

Shahee, Aga, E-mail: agashahee@gmail.com [UGC-DAE Consortium for Scientific Research, University Campus, Khandwa Road, Indore 452001 (India); Department of Physics, IIT Bombay, Powai, Mumbai 400076 (India); Sharma, Shivani; Singh, K.; Lalla, N.P. [UGC-DAE Consortium for Scientific Research, University Campus, Khandwa Road, Indore 452001 (India)

2017-07-15

Highlights: • Temperature and magnetic field driven coupled magneto-structural phase transition in Nd{sub 0.49}Sr{sub 0.51}MnO{sub 3+δ}. • Microscopic evidence of strong spin-charge-lattice coupling. • Iso-thermal magnetic field driven structure phase transition. • Field-driven structural phase transition origin of observed 1st order type CMR effect. - Abstract: Comprehensive X-ray diffraction (XRD) studies have been performed at different temperature (T) (4.2–300 K) and magnetic field (H) (0–8 T) to understand the evolution of crystal structure of Nd{sub 0.49}Sr{sub 0.51}MnO{sub 3+δ} (NSMO) under non ambient conditions. The T dependent XRD results show the abrupt change in the lattice parameters without any change in lattice symmetry at ∼200 K, which is associated with the first order structural phase transition from ferromagnetic to antiferromagnetic phase. This phase transition is strongly H dependent and shifted to lower temperature (∼150 K) on the application of 8 T field with phase coexistence (high temperature phase ∼18%), even down to 4.2 K. Isothermal XRD results at 150 K under different H clearly illustrate the H induced first order structural phase transition. The critical H at which this phase transformation starts is ∼1 T, with rapid growth above 4 T with hysteretic nature during increasing and decreasing H. These results are supported with the resistivity and magnetoresistance results and affirm the strong spin-lattice coupling in NSMO. Our detail studies reveal the structural correlations to the observed colossal magnetoresistance and magnetocaloric effect in this material.

Acoustic waves and the detectability of first-order phase transitions by eLISA

Science.gov (United States)

Weir, David J.

2017-05-01

In various extensions of the Standard Model it is possible that the electroweak phase transition was first order. This would have been a violent process, involving the formation of bubbles and associated shock waves. Not only would the collision of these bubbles and shock waves be a detectable source of gravitational waves, but persistent acoustic waves could enhance the signal and improve prospects of detection by eLISA. I summarise the results of a recent campaign to model such a phase transition based on large-scale hydrodynamical simulations, and its implications for the eLISA mission.

Search for the lepton-flavor violating decays $B^0_s \\rightarrow e^{\\pm}\\mu^{\\mp}$ and $B^0 \\rightarrow e^{\\pm} \\mu^{\\mp}$

CERN Document Server

Aaij, R.; Adinolfi, M.; Adrover, C.; Affolder, A.; Ajaltouni, Z.; Albrecht, J.; Alessio, F.; Alexander, M.; Ali, S.; Alkhazov, G.; Alvarez Cartelle, P.; Alves Jr, A.A.; Amato, S.; Amerio, S.; Amhis, Y.; Anderlini, L.; Anderson, J.; Andreassen, R.; Andrews, J.E.; Appleby, R.B.; Aquines Gutierrez, O.; Archilli, F.; Artamonov, A.; Artuso, M.; Aslanides, E.; Auriemma, G.; Baalouch, M.; Bachmann, S.; Back, J.J.; Baesso, C.; Balagura, V.; Baldini, W.; Barlow, R.J.; Barschel, C.; Barsuk, S.; Barter, W.; Bauer, Th.; Bay, A.; Beddow, J.; Bedeschi, F.; Bediaga, I.; Belogurov, S.; Belous, K.; Belyaev, I.; Ben-Haim, E.; Bencivenni, G.; Benson, S.; Benton, J.; Berezhnoy, A.; Bernet, R.; Bettler, M.-O.; van Beuzekom, M.; Bien, A.; Bifani, S.; Bird, T.; Bizzeti, A.; Bjørnstad, P.M.; Blake, T.; Blanc, F.; Blouw, J.; Blusk, S.; Bocci, V.; Bondar, A.; Bondar, N.; Bonivento, W.; Borghi, S.; Borgia, A.; Bowcock, T.J.V.; Bowen, E.; Bozzi, C.; Brambach, T.; van den Brand, J.; Bressieux, J.; Brett, D.; Britsch, M.; Britton, T.; Brook, N.H.; Brown, H.; Burducea, I.; Bursche, A.; Busetto, G.; Buytaert, J.; Cadeddu, S.; Callot, O.; Calvi, M.; Calvo Gomez, M.; Camboni, A.; Campana, P.; Campora Perez, D.; Carbone, A.; Carboni, G.; Cardinale, R.; Cardini, A.; Carranza-Mejia, H.; Carson, L.; Carvalho Akiba, K.; Casse, G.; Castillo Garcia, L.; Cattaneo, M.; Cauet, Ch.; Cenci, R.; Charles, M.; Charpentier, Ph.; Chen, P.; Chiapolini, N.; Chrzaszcz, M.; Ciba, K.; Cid Vidal, X.; Ciezarek, G.; Clarke, P.E.L.; Clemencic, M.; Cliff, H.V.; Closier, J.; Coca, C.; Coco, V.; Cogan, J.; Cogneras, E.; Collins, P.; Comerma-Montells, A.; Contu, A.; Cook, A.; Coombes, M.; Coquereau, S.; Corti, G.; Couturier, B.; Cowan, G.A.; Craik, D.C.; Cunliffe, S.; Currie, R.; D'Ambrosio, C.; David, P.; David, P.N.Y.; Davis, A.; De Bonis, I.; De Bruyn, K.; De Capua, S.; De Cian, M.; De Miranda, J.M.; De Paula, L.; De Silva, W.; De Simone, P.; Decamp, D.; Deckenhoff, M.; Del Buono, L.; Déléage, N.; Derkach, D.; Deschamps, O.; Dettori, F.; Di Canto, A.; Dijkstra, H.; Dogaru, M.; Donleavy, S.; Dordei, F.; Dosil Suárez, A.; Dossett, D.; Dovbnya, A.; Dupertuis, F.; Durante, P.; Dzhelyadin, R.; Dziurda, A.; Dzyuba, A.; Easo, S.; Egede, U.; Egorychev, V.; Eidelman, S.; van Eijk, D.; Eisenhardt, S.; Eitschberger, U.; Ekelhof, R.; Eklund, L.; El Rifai, I.; Elsasser, Ch.; Falabella, A.; Färber, C.; Fardell, G.; Farinelli, C.; Farry, S.; Fave, V.; Ferguson, D.; Fernandez Albor, V.; Ferreira Rodrigues, F.; Ferro-Luzzi, M.; Filippov, S.; Fiore, M.; Fitzpatrick, C.; Fontana, M.; Fontanelli, F.; Forty, R.; Francisco, O.; Frank, M.; Frei, C.; Frosini, M.; Furcas, S.; Furfaro, E.; Gallas Torreira, A.; Galli, D.; Gandelman, M.; Gandini, P.; Gao, Y.; Garofoli, J.; Garosi, P.; Garra Tico, J.; Garrido, L.; Gaspar, C.; Gauld, R.; Gersabeck, E.; Gersabeck, M.; Gershon, T.; Ghez, Ph.; Gibson, V.; Giubega, L.; Gligorov, V.V.; Göbel, C.; Golubkov, D.; Golutvin, A.; Gomes, A.; Gordon, H.; Grabalosa Gándara, M.; Graciani Diaz, R.; Granado Cardoso, L.A.; Graugés, E.; Graziani, G.; Grecu, A.; Greening, E.; Gregson, S.; Griffith, P.; Grünberg, O.; Gui, B.; Gushchin, E.; Guz, Yu.; Gys, T.; Hadjivasiliou, C.; Haefeli, G.; Haen, C.; Haines, S.C.; Hall, S.; Hamilton, B.; Hampson, T.; Hansmann-Menzemer, S.; Harnew, N.; Harnew, S.T.; Harrison, J.; Hartmann, T.; He, J.; Head, T.; Heijne, V.; Hennessy, K.; Henrard, P.; Hernando Morata, J.A.; van Herwijnen, E.; Hicheur, A.; Hicks, E.; Hill, D.; Hoballah, M.; Hombach, C.; Hopchev, P.; Hulsbergen, W.; Hunt, P.; Huse, T.; Hussain, N.; Hutchcroft, D.; Hynds, D.; Iakovenko, V.; Idzik, M.; Ilten, P.; Jacobsson, R.; Jaeger, A.; Jans, E.; Jaton, P.; Jawahery, A.; Jing, F.; John, M.; Johnson, D.; Jones, C.R.; Joram, C.; Jost, B.; Kaballo, M.; Kandybei, S.; Kanso, W.; Karacson, M.; Karbach, T.M.; Kenyon, I.R.; Ketel, T.; Keune, A.; Khanji, B.; Kochebina, O.; Komarov, I.; Koopman, R.F.; Koppenburg, P.; Korolev, M.; Kozlinskiy, A.; Kravchuk, L.; Kreplin, K.; Kreps, M.; Krocker, G.; Krokovny, P.; Kruse, F.; Kucharczyk, M.; 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Schwemmer, R.; Sciascia, B.; Sciubba, A.; Seco, M.; Semennikov, A.; Senderowska, K.; Sepp, I.; Serra, N.; Serrano, J.; Seyfert, P.; Shapkin, M.; Shapoval, I.; Shatalov, P.; Shcheglov, Y.; Shears, T.; Shekhtman, L.; Shevchenko, O.; Shevchenko, V.; Shires, A.; Silva Coutinho, R.; Sirendi, M.; Skwarnicki, T.; Smith, N.A.; Smith, E.; Smith, J.; Smith, M.; Sokoloff, M.D.; Soler, F.J.P.; Soomro, F.; Souza, D.; Souza De Paula, B.; Spaan, B.; Sparkes, A.; Spradlin, P.; Stagni, F.; Stahl, S.; Steinkamp, O.; Stevenson, S.; Stoica, S.; Stone, S.; Storaci, B.; Straticiuc, M.; Straumann, U.; Subbiah, V.K.; Sun, L.; Swientek, S.; Syropoulos, V.; Szczekowski, M.; Szczypka, P.; Szumlak, T.; T'Jampens, S.; Teklishyn, M.; Teodorescu, E.; Teubert, F.; Thomas, C.; Thomas, E.; van Tilburg, J.; Tisserand, V.; Tobin, M.; Tolk, S.; Tonelli, D.; Topp-Joergensen, S.; Torr, N.; Tournefier, E.; Tourneur, S.; Tran, M.T.; Tresch, M.; Tsaregorodtsev, A.; Tsopelas, P.; Tuning, N.; Ubeda Garcia, M.; Ukleja, A.; Urner, D.; Ustyuzhanin, A.; Uwer, U.; Vagnoni, V.; Valenti, G.; Vallier, A.; Van Dijk, M.; Vazquez Gomez, R.; Vazquez Regueiro, P.; Vázquez Sierra, C.; Vecchi, S.; Velthuis, J.J.; Veltri, M.; Veneziano, G.; Vesterinen, M.; Viaud, B.; Vieira, D.; Vilasis-Cardona, X.; Vollhardt, A.; Volyanskyy, D.; Voong, D.; Vorobyev, A.; Vorobyev, V.; Voß, C.; Voss, H.; Waldi, R.; Wallace, C.; Wallace, R.; Wandernoth, S.; Wang, J.; Ward, D.R.; Watson, N.K.; Webber, A.D.; Websdale, D.; Whitehead, M.; Wicht, J.; Wiechczynski, J.; Wiedner, D.; Wiggers, L.; Wilkinson, G.; Williams, M.P.; Williams, M.; Wilson, F.F.; Wimberley, J.; Wishahi, J.; Witek, M.; Wotton, S.A.; Wright, S.; Wu, S.; Wyllie, K.; Xie, Y.; Xing, Z.; Yang, Z.; Young, R.; Yuan, X.; Yushchenko, O.; Zangoli, M.; Zavertyaev, M.; Zhang, F.; Zhang, L.; Zhang, W.C.; Zhang, Y.; Zhelezov, A.; Zhokhov, A.; Zhong, L.; Zvyagin, A.

2013-01-01

A search for the lepton-flavour violating decays $B^0_s \\rightarrow e^{\\pm}\\mu^{\\mp}$ and $B^0 \\rightarrow e^{\\pm} \\mu^{\\mp}$ is performed with a data sample, corresponding to an integrated luminosity of 1.0 fb$^{-1}$ of $pp$ collisions at $\\sqrt{s} = 7$, TeV, collected by the LHCb experiment. The observed number of $B^0_s \\to e^{\\pm} \\mu^{\\mp}$ and $B^0 \\to e^{\\pm} \\mu^{\\mp}$ candidates is consistent with background expectations. Upper limits on the branching fractions of both decays are determined to be $BR(B^0_s \\to e^{\\pm} \\mu^{\\mp} 107$ TeV/c$^2$ and $M_{\\rm LQ} (B^0 \\to e^{\\pm} \\mu^{\\mp}) > 126$ TeV/c$^2$ at 95% C.L., and are a factor of two higher than the previous bounds.

Structural phase transition at the percolation threshold in epitaxial (La0.7Ca0.3MnO3)1-x:(MgO)x nanocomposite films.

Science.gov (United States)

Moshnyaga, V; Damaschke, B; Shapoval, O; Belenchuk, A; Faupel, J; Lebedev, O I; Verbeeck, J; van Tendeloo, G; Mücksch, M; Tsurkan, V; Tidecks, R; Samwer, K

2003-04-01

'Colossal magnetoresistance' in perovskite manganites such as La0.7Ca0.3MnO3 (LCMO), is caused by the interplay of ferro-paramagnetic, metal-insulator and structural phase transitions. Moreover, different electronic phases can coexist on a very fine scale resulting in percolative electron transport. Here we report on (LCMO)1-x:(MgO)x (0 strain. The largest colossal magnetoresistance of 10(5)% was observed at the percolation threshold in the conductivity at xc 0.3, which is coupled to a structural phase transition from orthorhombic (0 < x < or 0.1) to rhombohedral R3c structure (0.33 < or = x < or = 0.8). An increase of the Curie temperature for the Rc phase was observed. These results may provide a general method for controlling the magnetotransport properties of manganite-based composite films by appropriate choice of the second phase.

77 FR 5252 - Federal Travel Regulation; GSA E-Gov Travel Service (ETS) Transition to E-Gov Travel Service 2...

Science.gov (United States)

2012-02-02

... Travel Regulation; GSA E-Gov Travel Service (ETS) Transition to E-Gov Travel Service 2 (ETS2) AGENCY..., ETS Program Manager Center for Travel Management (QMCD), Office of Travel and Transportation Services (QMC), at [email protected] or (703) 605-2151. SUPPLEMENTARY INFORMATION: The Federal Travel...

Magnetic transitions in the system YBa2Cu/sub 2.8/Co/sub 0.2/O/sub 6+y/

International Nuclear Information System (INIS)

Miceli, P.F.; Tarascon, J.M.; Barboux, P.; Greene, L.H.; Bagley, B.G.; Hull, G.W.; Giroud, M.; Rhyne, J.J.; Neumann, D.A.; National Institute of Standards and Technology, Gaithersburg, Maryland 20899)

1989-01-01

We have studied the oxygen dependence of the two magnetic transitions (antiferromagnetic ordering of chains and planes) in YBa 2 Cu/sub 2.8/Co/sub 0.2/O/sub 6+y/ using neutron scattering. It is found that both transition temperatures increase with decreasing oxygen concentration. At y approx. 0.37 ( equivalent to y 0 ) the two transition temperatures are equal, so that chains and planes order at a single transition temperature for y less than or equal to y/sub 0/. For y=1 the compound is superconducting at 60 K. Therefore, this system qualitatively exhibits the magnetic and superconducting properties of pure YBa 2 Cu 3 O/sub 6+y/ while providing important insight on the oxygen dependence of chain site magnetic ordering. A discussion is presented which also includes results on Ni and Al substitutions

Measurement of the branching ratios ψ'→e+e-, ψ'→J/ψπ0π0 and ψ'→J/ψη

International Nuclear Information System (INIS)

Ambrogiani, M.; Bagnasco, S.; Baldini, W.; Bettoni, D.; Borreani, G.; Buzzo, A.; Calabrese, R.; Cardarelli, M.; Cester, R.; Dalpiaz, P.

2000-01-01

We have determined the following ψ ' branching ratios using the large event sample collected by Fermilab experiment E835 in the reaction pp(bar sign)→ψ ' : B(ψ ' →e + e - )=(7.4±0.2±0.7)x10 -3 , B(ψ ' →J/ψπ 0 π 0 )=(18.7±0.9±1.3)% and B(ψ ' →J/ψη)=(4.1±0.3±0.5)%. (c) 2000 The American Physical Society

Tight regulation of a timed nuclear import wave of EKLF by PKCθ and FOE during Pro-E to Baso-E transition.

Science.gov (United States)

Shyu, Yu-Chiau; Lee, Tung-Liang; Chen, Xin; Hsu, Pang-Hung; Wen, Shau-Ching; Liaw, Yi-Wei; Lu, Chi-Huan; Hsu, Po-Yen; Lu, Mu-Jie; Hwang, JauLang; Tsai, Ming-Daw; Hwang, Ming-Jing; Chen, Jim-Ray; Shen, Che-Kun James

2014-02-24

Erythropoiesis is a highly regulated process during which BFU-E are differentiated into RBCs through CFU-E, Pro-E, PolyCh-E, OrthoCh-E, and reticulocyte stages. Uniquely, most erythroid-specific genes are activated during the Pro-E to Baso-E transition. We show that a wave of nuclear import of the erythroid-specific transcription factor EKLF occurs during the Pro-E to Baso-E transition. We further demonstrate that this wave results from a series of finely tuned events, including timed activation of PKCθ, phosphorylation of EKLF at S68 by P-PKCθ(S676), and sumoylation of EKLF at K74. The latter EKLF modifications modulate its interactions with a cytoplasmic ankyrin-repeat-protein FOE and importinβ1, respectively. The role of FOE in the control of EKLF nuclear import is further supported by analysis of the subcellular distribution patterns of EKLF in FOE-knockout mice. This study reveals the regulatory mechanisms of the nuclear import of EKLF, which may also be utilized in the nuclear import of other factors. Copyright © 2014 Elsevier Inc. All rights reserved.

Metal-insulator transition upon heating and negative-differential-resistive-switching induced by self-heating in BaCo0.9Ni0.1S1.8

International Nuclear Information System (INIS)

Fisher, B.; Genossar, J.; Chashka, K. B.; Patlagan, L.; Reisner, G. M.

2014-01-01

The layered compound BaCo 1−x Ni x S 2−y (0.05  1−x Ni x S 2−y (nominal x = 0.1 and y = 0.2). These were due to the steep metal to insulator transition upon heating followed by the activated behavior of the resistivity above the transition. The major role of Joule heating in switching is supported by the absence of nonlinearity in the current as function of voltage, I(V), obtained in pulsed measurements, in the range of electric fields relevant to d.c. measurements. The voltage-controlled negative differential resistance around the threshold for switching was explained by a simple model of self-heating. The main difficulty in modeling I(V) from the samples resistance as function of temperature R(T) was the progressive increase of R(T), and to a lesser extend the decrease of the resistance jumps at the transitions, caused by the damage induced by cycling through the transitions by heating or self-heating. This was dealt with by following systematically R(T) over many cycles and by using the data of R(T) in the heating cycle closest to that of the self-heating one

Investigation of structure, specific heat and superconducting transition in Mg1-xAlxB2(x∼0.5)

International Nuclear Information System (INIS)

Xiang, J.Y.; Zheng, D.N.; Lang, P.L.; Zhao, Z.X.; Luo, J.L.

2004-01-01

We have carried out structure, magnetic and specific heat measurements on aluminum doped magnetism diboride samples Mg 1-x Al x B 2 in order to investigate possible superconductivity at the x=0.5 concentration. A diamagnetic signal was observed in magnetization measurements accompanied by a decrease in resistivity. However, the diamagnetic signal was extremely small as compared to what expected from full diamagnetism. Also, the transition both in magnetization and resistance was very broad. We propose that the diamagnetism is due to a very small amount of superconducting phase such as MgB 2 and the resistive transition is due to the percolation behavior. Furthermore, we performed specific heat measurements, which are considered as a tool to investigate the bulk nature of superconducting transition, on the x=0.5 sample to verify the existence of superconductivity. We observed no evident superconducting transition in the entire temperature region from 2 to 300 K. The undistinguishable data between 0 and 5 T magnetic fields also indicated the absence of bulk superconductivity in the x=0.5 sample

QCD Factorizations in Exclusive {gamma}*{gamma}*{yields}{rho}{sub L}{sup 0}{rho}{sub L}{sup 0}

Energy Technology Data Exchange (ETDEWEB)

Pire, B. [CPHT, Ecole Polytechnique, CNRS, Palaiseau (France); Segond, M. [LPTHE, Universite Paris 6 and 7, CNRS, Paris (France); LPT, Universite Paris-Sud, CNRS, Orsay (France); Szymanowski, L. [CPHT, Ecole Polytechnique, CNRS, Palaiseau (France); SINS, Warsaw (Poland); Wallon, S. [LPT, Universite Paris-Sud, CNRS, Orsay (France)

2008-11-15

The exclusive process e{sup +}e{sup -}{yields}e{sup +}e{sup -}{rho}{sub L}{sup 0}{rho}{sub L}{sup 0} allows to study various dynamics and factorization properties of perturbative QCD. At moderate energy, we demonstrate how collinearQCD factorization emerges, involving either generalized distribution amplitudes (GDA) or transition distribution amplitudes (TDA). At higher energies, in the Regge limit of QCD, we show that it offers a promising probe of the BFKL resummation effects to be studied at ILC.

Thermal-induced structural transition and depolarization behavior in (Bi0.5Na0.5)TiO3-BiAlO3 ceramics

Science.gov (United States)

Peng, Ping; Nie, Hengchang; Cheng, Guofeng; Liu, Zhen; Wang, Genshui; Dong, Xianlin

2018-03-01

The depolarization temperature Td determines the upper temperature limit for the application of piezoelectric materials. However, the origin of depolarization behavior for Bi-based materials still remains controversial and the mechanism is intricate for different (Bi0.5Na0.5)TiO3-based systems. In this work, the structure and depolarization behavior of (1-x)(Bi0.5Na0.5)TiO3-xBiAlO3 (BNT-BA, x = 0, 0.02, 0.04, 0.06, 0.07) ceramics were investigated using a combination of X-ray diffraction and electrical measurements. It was found that as temperature increased, the induced long-range ferroelectric phase irreversibly transformed to the relaxor phase as evidenced by the temperature-dependent ferroelectric and dielectric properties, which corresponded to a gradual structural change from the rhombohedral to the pseudocubic phase. Therefore, the thermal depolarization behavior of BNT-BA ceramics was proposed to be directly related to the rhombohedral-pseudocubic transition. Furthermore, Td (obtained from thermally stimulated depolarization currents curves) was higher than the induced ferroelectric-relaxor phase transition temperature TFR (measured from dielectric curves). The phenomenon was quite different from other reported BNT-based systems, which may suggest the formation of polar nanoregions (PNRs) within macrodomains prior to the detexturation of short-range ferroelectric domains with PNRs or nanodomains.

A study of the semileptonic decay mode D0 → K-e+nu/sub e/

International Nuclear Information System (INIS)

Anjos, J.C.; Appel, J.A.; Bracker, S.B.

1987-09-01

We present an analysis of the exclusive semileptonic decay mode D 0 → K - e + nu/sub e/. We have measured the ratio of decay rates Γ(D 0 → K - e + nu/sub e/)/Γ(D 0 → K - π + ). After correcting for the reconstruction efficiencies and subtracting the contribution from other decay modes we have found the ratio to be equal to 0.77 +- 0.12(stat) +- 0.13(syst)

Transition quadrupole moments in the superdeformed band of 40Ca

International Nuclear Information System (INIS)

Chiara, C.J.; Ideguchi, E.; Devlin, M.; LaFosse, D.R.; Lerma, F.; Reviol, W.; Ryu, S.K.; Sarantites, D.G.; Baktash, C.; Galindo-Uribarri, A.; Carpenter, M.P.; Janssens, R.V.F.; Lauritsen, T.; Lister, C.J.; Reiter, P.; Seweryniak, D.; Fallon, P.; Goergen, A.; Macchiavelli, A.O.; Rudolph, D.

2003-01-01

The transition quadrupole moments Q t for the superdeformed band in 40 Ca have been determined through thin-target Doppler-shift attenuation analyses. A best-fit value of Q t =1.30±0.05 e b is obtained when a single value is assumed for the entire band. Fitting separate quadrupole moments for in-band transitions decaying from the high-spin states and the presumably admixed low-spin states results in Q t (high)=1.81 -0.26 +0.41 e b and Q t (low)=1.18 -0.05 +0.06 e b, respectively. Q t values extracted for individual transitions in a Doppler-broadened line-shape analysis also indicate smaller Q t values at lower spins. These results are consistent with the interpretation of this band as an eight-particle-eight-hole superdeformed band with a significant admixture of less-collective configurations at low spins

Hydrostatic pressure study of the structural phase transitions and superconductivity in single crystals of (Ba1-xKx)Fe2As2 (x=0 and 0.45) and CaFe2As2

International Nuclear Information System (INIS)

Torikachvili, M.S.; Bud'ko, S.L.; Ni Ni; Canfield, P.C.

2009-01-01

We studied the effect of hydrostatic pressure (P) on the structural phase transitions and superconductivity in the ternary and pseudo-ternary iron arsenides CaFe 2 As 2 , BaFe 2 As 2 , and (Ba 0.55 K 0.45 )Fe 2 As 2 , by means of measurements of electrical resistivity (ρ) in the 1.8-300 K temperature (T) range, pressures up to 20 kbar, and magnetic fields up to 9 T. CaFe 2 As 2 and BaFe 2 As 2 (lightly doped with Sn) display structural phase transitions near 170 and 85 K, respectively, and do not exhibit superconductivity in ambient pressure, while K-doped (Ba 0.55 K 0.45 )Fe 2 As 2 is superconducting for T 2 As 2 is to shift the onset of the crystallographic transformation down in temperature at the rate of ∼-1.04 K/kbar, while shifting the whole ρ(T) curves downward, whereas its effect on superconducting (Ba 0.55 K 0.45 )Fe 2 As 2 is to shift the onset of superconductivity to lower temperatures at the rate of ∼-0.21 K/kbar. The effect of pressure on CaFe 2 As 2 is first to suppress the crystallographic transformation and induce superconductivity with onset near 12 K very rapidly, i.e., for P c2 ) data in (Ba 0.55 K 0.45 )Fe 2 As 2 and CaFe 2 As 2 are discussed.

Reentrant metal-insulator transition in the Cu-doped manganites La1-x Pbx MnO3 (x˜0.14) single crystals

Science.gov (United States)

Zhao, B. C.; Song, W. H.; Ma, Y. Q.; Ang, R.; Zhang, S. B.; Sun, Y. P.

2005-10-01

Single crystals of La1-x Pbx Mn1-y-z Cuy O3 ( x˜0.14 ; y=0 ,0.01,0.02,0.04,0.06; z=0.02 ,0.08,0.11,0.17,0.20) are grown by the flux growth technique. The effect of Cu doping at the Mn-site on magnetic and transport properties is studied. All studied samples undergo a paramagnetic-ferromagnetic transition. The Curie temperature TC decreases and the transition becomes broader with increasing Cu-doping level. The high-temperature insulator-metal (I-M) transition moves to lower temperature with increasing Cu-doping level. A reentrant M-I transition at the low temperature T* is observed for samples with y⩾0.02 . In addition, T* increases with increasing Cu-doping level and is not affected by applied magnetic fields. Accompanying the appearance of T* , there exists a large, almost constant magnetoresistance (MR) below T* except for a large MR peak near TC . This reentrant M-I transition is ascribed to charge carrier localization due to lattice distortion caused by the Cu doping at Mn sites.

Glass-like and Verwey transitions in magnetite in details

Czech Academy of Sciences Publication Activity Database

Janů, Zdeněk; Hadač, J.; Švindrych, Z.

2007-01-01

Roč. 310, - (2007), e203-e205 ISSN 0304-8853 Institutional research plan: CEZ:AV0Z10100520 Keywords : metal-insulator transition s and other electronic transition s * spin glass es and other random magnets * dynamic properties Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 1.704, year: 2007

Measurement of the e+e- annihilation into the 4-leptonic final states e+e-e+e-, e+e-μ+μ-, and μ+μ-μ+μ- on the Z0 resonance

International Nuclear Information System (INIS)

Lehner, D.

1993-01-01

In this thesis results are presented, which are based on data, which were taken up with the detector of the ALEPH collaboration at the e + e - storage ring LEP in Geneva in the years 1990 and 1991. At c.m. energies between 88.25 GeV and 94.25 GeV the three reactions e + e - →μ + μ - μ + μ - , e + e - → e + e - μ + μ - and e + e - → e + e - e + e - were studied. After subtraction of the background from the ALEPH date the following N exp / μ +μ - μ + μ - = 4.88 ± (2.24) stat N exp / e + e - μ + μ - 24.1 (5.1) stat ± (0.16) sys and N exp / e + e - e + e - = 10.4 ± (4.1 stat) ± (0.44) sys results, while the event numbers expected according to the standard model are given by N theo / μ + μ - μ + μ - = 3.46 (0.04) stat ± (0.42) sys N theo / e + e - μ + μ - = 14.48 ± (0.19) stat ± (1.97) sys and N theo / e + e - e + e - = 12.24 ± (0.21) stat ± (1.46) sys. An X 2 test shows a confidence level of 30% for the hypothesis of the description of the data by the standard model of the electroweak interactions. Furthermore the invariant masses of the lepton pairs of the three final states studied were analyzed and a test of the universality of the photoproduction of electron and muon pairs was performed. The each measured data are in accordance with the predictions of the standard model. (orig./HSI) [de

0-π transition in a superconductor/carbon nanotube quantum dot/superconductor junction

International Nuclear Information System (INIS)

Yu Yong; Liang Qifeng; Dong Jinming

2010-01-01

Josephson current, passing through a superconductor/carbon nanotube quantum dot/superconductor junction (S/CNT-QD/S), has been investigated using the nonequilibrium Green's function method in the Hartree-Fock approximation, where the characteristic two orbital degrees of freedom of the carbon nanotubes (CNTs) are considered as the orbital pseudospins, which has an important effect on the transport properties of the S/CNT-QD/S junction. It has been found that: 1) If the orbital pseudospin doesn't conserve in the Cooper pair's tunneling process, the 0-π phase transition of the junction appears when the average electron occupation number in the CNT-QDs is odd, which is well consistent with the experimental observations. 2) More importantly, if the orbital pseudospin conserves, the 0-π phase transition could appear for the junction with an even average electron occupation number on the CNT-QDs, in contrast with an odd number of electrons in the ordinary QDs of the S/QD/S junctions, which is predicted to be possibly observed in future experiment with a weak cross scattering between the two orbital channels of the CNTs. (author)

The Avahan Transition: Effects of Transition Readiness on Program Institutionalization and Sustained Outcomes.

Directory of Open Access Journals (Sweden)

Sachiko Ozawa

Full Text Available With declines in development assistance for health and growing interest in country ownership, donors are increasingly faced with the task of transitioning health programs to local actors towards a path to sustainability. Yet there is little available guidance on how to measure and evaluate the success of a transition and its subsequent effects. This study assesses the transition of the Avahan HIV/AIDS prevention program in India to investigate how preparations for transition affected continuation of program activities post-transition.Two rounds of two surveys were conducted and supplemented by data from government and Avahan Computerized Management Information Systems (CMIS. Exploratory factor analysis was used to develop two measures: 1 transition readiness pre-transition, and 2 institutionalization (i.e. integration of initial program systems into organizational procedures and behaviors post-transition. A fixed effects model was built to examine changes in key program delivery outcomes over time. An ordinary least square regression was used to assess the relationship between transition readiness and sustainability of service outcomes both directly, and indirectly through institutionalization.Transition readiness data revealed 3 factors (capacity, alignment and communication, on a 15-item scale with adequate internal consistency (alpha 0.73. Institutionalization was modeled as a unidimensional construct, and a 12-item scale demonstrated moderate internal consistency (alpha 0.60. Coverage of key populations and condom distribution were sustained compared to pre-transition levels (p<0.01. Transition readiness, but not institutionalization, predicted sustained outcomes post-transition. Transition readiness did not necessarily lead to institutionalization of key program elements one year after transition.Greater preparedness prior to transition is important to achieve better service delivery outcomes post-transition. This paper illustrates a

Temperature-dependent Raman spectra and electrical properties of 0.69Pb(Mg{sub 1/3}Nb{sub 2/3})O{sub 3}-0.31PbTiO{sub 3} single crystals

Energy Technology Data Exchange (ETDEWEB)

Fang, Bijun [Changzhou University, School of Materials Science and Engineering, Jiangsu Collaborative Innovation Center of Photovolatic Science and Engineering, Changzhou (China); Liu, Xing [Changzhou University, School of Materials Science and Engineering, Jiangsu Collaborative Innovation Center of Photovolatic Science and Engineering, Changzhou (China); Chinese Academy of Sciences, Key Laboratory of Inorganic Function Material and Device, Shanghai (China); Li, Xiaobing; Zhao, Xiangyong; Luo, Haosu [Chinese Academy of Sciences, Key Laboratory of Inorganic Function Material and Device, Shanghai (China); Ding, Jianning [Changzhou University, School of Materials Science and Engineering, Jiangsu Collaborative Innovation Center of Photovolatic Science and Engineering, Changzhou (China); Jiangsu University, School of Material Science and Engineering, Zhenjiang (China)

2016-09-15

The temperature-dependent Raman spectra and electrical properties of the 0.69Pb(Mg{sub 1/3}Nb{sub 2/3})O{sub 3}-0.31PbTiO{sub 3} (0.69PMN-0.31PT) single crystals were investigated. Based on the group theory, the poled 0.69PMN-0.31PT single crystals belong to the monoclinic crystal system, which was confirmed by the room-temperature Raman spectra. The 0.69PMN-0.31PT single crystals experience successive structural phase transitions, i.e., a monoclinic-tetragonal (FE{sub M}-FE{sub T}) phase transition at T{sub M-T} and a tetragonal-cubic (FE{sub T}-P{sub C}) phase transition at T{sub m} determined by the dielectric measurement. Due to the enhancement of long-range order, their FE{sub M}-FE{sub T} phase transition becomes more obvious after the poling process. The wavenumbers and line widths of the 271, 502, 575, 795 cm{sup -1} Raman modes, and the intensity ratios of I{sub 271cm}{sup {sub -}{sub 1}}/I{sub 795cm}{sup {sub -}{sub 1}} and I{sub 502cm}{sup {sub -}{sub 1}}/I{sub 575cm}{sup {sub -}{sub 1}} exhibit obvious anomalies around T{sub M-T} and T{sub m}, which are closely related to the FE{sub M}-FE{sub T} and FE{sub T}-P{sub C} phase transitions. The temperature and electric field (E)-induced phase transitions are observed in the unipolar strain-E (S-E) curves. The converse piezoelectric constant (d{sub 33}), maximum strain value (S{sub max}%) and longitudinal electrostrictive coefficient (Q) increase considerably around the ferroelectric phase transition temperature T{sub M-T}. (orig.)

B (E2) values of transitions from kπ= 0+→ 2+ vibrational bands in some well deformed heavy nuclei

International Nuclear Information System (INIS)

Singh, M.; Varshney, Mani; Gupta, D.K.; Bihari, Chhail; Singh, Yuvraj; Varshney, A.K.; Gupta, K.K

2009-01-01

There is simultaneous reduced B (E2) values of low-lying K π= 0 + → 2 + states, indicating a beta vibration like structure as well as the two particle transfer cross-section which suggest a pairing vibration like character and interpreted that low-lying k π= 0 + → 2 + resonance are classical beta vibrations. Recently, similar doubts about the origin of beta vibrations from surface oscillation have also been published

EXAFS study of Mn1.28Fe0.67P0.46Si0.54 compound with first-order phase transition

International Nuclear Information System (INIS)

L, Yingjie; Huliyageqi, B; Haschaolu, W; Song, Zhiqiang; Tegus, O; Nakai, Ikuo

2014-01-01

Highlights: • We have investigated the Fe and Mn K edge XAFS spectra of the Mn 1.28 Fe 0.67 P 0.46 Si 0.54 compound at 25 K and 295 K. • The site occupation of the Fe and Mn atoms and local structure of Mn 1.28 Fe 0.67 P 0.46 Si 0.54 are determined. • The atomic distances between Fe–Fe in c-plane for the ferromagnetic state are larger than those in the paramagnetic state. - Abstract: The Fe 2 P-type MnFe(P,Si) compounds are investigated by means of magnetic measurements and X-ray absorption fine structure spectroscopy. Magnetic measurements show that the Mn 1.28 Fe 0.67 P 0.46 Si 0.54 compound undergoes a first-order phase transition at the Curie temperature of 254 K. The Fe K-edge and Mn K-edge X-ray absorption fine structure spectra show that Mn atom mainly located at the 3g sites, while the 3f sites are occupied by Fe atoms and Mn atom randomly. The distances between the Fe atom and its nearest neighbor atoms in a triangle Fe–Mn–Fe change from 2.80 Å at 25 K to 2.74 Å at 300 K. On the other hand, the distances between Fe atom and its second neighbor atoms change from 4.06 Å at 25 K to 4.02 Å at 300 K

Metal-insulator transition upon heating and negative-differential-resistive-switching induced by self-heating in BaCo{sub 0.9}Ni{sub 0.1}S{sub 1.8}

Energy Technology Data Exchange (ETDEWEB)

Fisher, B.; Genossar, J.; Chashka, K. B.; Patlagan, L.; Reisner, G. M. [Physics Department, Technion-Israel Institute of Technology, Haifa 32000 (Israel)

2014-04-14

The layered compound BaCo{sub 1−x}Ni{sub x}S{sub 2−y} (0.05 < x < 0.2 and 0.05 < y < 0.2) exhibits an unusual first-order structural and electronic phase transition from a low-T monoclinic paramagnetic metal to a high-T tetragonal antiferromagnetic insulator around 200 K with huge hysteresis (∼40 K) and large volume change (∼0.01). Here, we report on unusual voltage-controlled resistive switching followed by current-controlled resistive switching induced by self-heating in polycrystalline BaCo{sub 1−x}Ni{sub x}S{sub 2−y} (nominal x = 0.1 and y = 0.2). These were due to the steep metal to insulator transition upon heating followed by the activated behavior of the resistivity above the transition. The major role of Joule heating in switching is supported by the absence of nonlinearity in the current as function of voltage, I(V), obtained in pulsed measurements, in the range of electric fields relevant to d.c. measurements. The voltage-controlled negative differential resistance around the threshold for switching was explained by a simple model of self-heating. The main difficulty in modeling I(V) from the samples resistance as function of temperature R(T) was the progressive increase of R(T), and to a lesser extend the decrease of the resistance jumps at the transitions, caused by the damage induced by cycling through the transitions by heating or self-heating. This was dealt with by following systematically R(T) over many cycles and by using the data of R(T) in the heating cycle closest to that of the self-heating one.

Energies, fine structures, and transitions of the core-excited sextet states "6S"e","o(n) and "6P"e","o(n) (n=1–5) of B-like ions

International Nuclear Information System (INIS)

Sun, Yan; Liu, Dong Dong; Mei, Mao Fei; Zhang, Chun Mei; Han, Chong; Hu, Feng; Gou, Bing Cong

2015-01-01

A comprehensive theoretical study of atomic characteristics of energy levels and transitions for the core-excited "6S"e","o(n) and "6P"e","o(n) (n=1–5) states of the boron isoelectronic sequence (Z=6–14) are investigated by the Rayleigh–Ritz variation method and multi-configuration interaction wavefunctions. The relativistic corrections and mass polarization effects are included by first-order perturbation theory. The configuration structures of the high-lying sextet series "6S"e","o(n) and "6P"e","o(n) (n=1–5) of the B-like ions are assigned. The transition rates and wavelengths for the electric dipole transitions "6S"e","o(n)—"6P"o","e(n) (n=1–5) of the B-like ions are calculated and compared with currently available theoretical and experimental data. Furthermore, the radiative transition rates and wavelengths for the important dipole transitions are discussed with the increase of nuclear charge number Z. The calculations will provide useful data for identification of spectral lines arising from the solar atmosphere and the experimental study in future work. - Highlights: • Energy and transition data of core-excited sextet states of B-like ions are studied. • Relativistic corrections, mass polarization effects are included in the calculation. • Radiative rates and transition wavelengths are discussed with the increase of Z. • Variation trend of transition rates and wavelengths are present with the n increase. • Some energy levels and transition data are reported for the first time.

Space, time and color in hadron production via e+ e- --> Z$^{0}$ and e+ e- --> W$^{+}$W$^{-}$

CERN Document Server

Ellis, John R.; Ellis, John; Geiger, Klaus

1996-01-01

The time-evolution of jets in hadronic e+ e- events at LEP is investigated in both position- and momentum-space, with emphasis on effects due to color flow and particle correlations. We address dynamical aspects of the four simultanously-evolving, cross-talking parton cascades that appear in the reaction e+ e- --> .gamma./Z.sup(0) --> W+W- --> q1 q~2 q3 q~4, and compare with the familiar two-parton cascades in e+ e- --> Z.sup(0) --> q1 q~2. We use a QCD statistical transport approach, in which the multiparticle final state is treated as an evolving mixture of partons and hadrons, whose proportions are controlled by their local space-time geography via standard perturbative QCD parton shower evolution and a phenomenological model for non-perturbative parton-cluster formation followed by cluster decays into hadrons. Our numerical simulations exhibit a characteristic "inside-outside" evolution simultanously in position and momentum space. We compare three different model treatments of color flow, and find large ...

Temperature dependent optical dispersion and electronic transitions of highly a-axis oriented 0.8Pb(Zn{sub 1/3}Nb{sub 2/3})O{sub 3}-0.2PbTiO{sub 3} films on SrTiO{sub 3} crystals: An ellipsometric evidence

Energy Technology Data Exchange (ETDEWEB)

Li, C.Q.; Zhang, J.Z.; Xu, L.P.; Zhu, J.J.; Duan, Z.H.; Hu, Z.G., E-mail: zghu@ee.ecnu.edu.cn; Chu, J.H.

2016-03-31

The relaxor ferroelectric 0.8Pb(Zn{sub 1/3}Nb{sub 2/3})O{sub 3}-0.2PbTiO{sub 3} (0.8PZN-0.2PT) films have been fabricated on (100) SrTiO{sub 3} substrates by the sol–gel method. The structure, optical properties and electronic transitions have been investigated using X-ray diffraction (XRD), atomic force microscopy, scanning electron microscopy and ellipsometric spectra. The pure perovskite phase with highly a-axis (100)-preferential orientation as well as low screw dislocation are extracted based on high resolution XRD. Moreover, the red-shift trend of the electronic transitions at about 3.01 eV as a function of temperature follows the Bose-Einstein law induced by the electron–phonon interactions and lattice thermal expansion. Interestingly, the different optical behavior and structure variation can be observed at about 500 K, which reveal tetragonal to cubic structural transformations for the 0.8PZN-0.2PT films. It indicates that the potential application of ellipsometric spectra in judging the phase transitions and symmetries of ferroelectric material. - Highlights: • The highly a-axis oriented as well as low screw dislocated films were fabricated. • The temperature-dependent evolution of band gap was investigated. • The tetragonal to cubic structural transformations were observed at about 500 K. • The electronic transition mechanism was discussed mainly by first-principles calculations.

Induced absorption spectra of the infrared fundamental band of molecular deuterium at 77 K: S1( J)+S0( J) transitions

International Nuclear Information System (INIS)

Gillard, P.G.; Prasad, R.D.G.; Reddy, S.P.

1984-01-01

The collision-induced spectra of the fundamental band of normal D 2 in the high frequency region 3200--3700 cm -1 were recorded for gas densities in the range 80--140 amagat at 77 K with a 2 m absorption cell. The contribution to the intensity of the band in this region comes from the high frequency wings of quadrupolar transitions S 1 ( J) and Q 1 ( J)+S 0 ( J) with J = 0 and 1, and from the group of transitions S 1 (2) and Q 1 ( J)+S 0 (2) with J = 0, 1, and 2 as well as from the relatively weaker double rotational transitions of the type S 1 ( J)+S 0 ( J); the latter transitions arise from the intermolecular interaction between the anisotropic component of the polarizability of one of the colliding pairs of molecules and the quadrupole field of the other. The experimental profiles were analyzed by assuming appropriate line shape functions and using the theoretical matrix elements of the quadrupole moment, isotropic polarizability, and anisotropy of polarizability of the D 2 molecule. From this analysis the characteristic half-width parameters delta/sub q/2 and delta/sub q/4 of the quadrupolar transitions and the binary and ternary absorption coefficients of the S 1 ( J)+S 0 ( J) transitions have been obtained. The experimental value of the binary absorption coefficient of S 1 (0)+S 0 (0) is (2.2 +- 0.1) x 10 -9 cm -1 amagat -2 and the corresponding theoretical value is 1.53 x 10 -9 cm -1 amagat -2

Phase transitions and optical characterization of lead-free piezoelectric (K0.5Na0.5)0.96Li0.04(Nb 0.8Ta0.2)O3 thin films

KAUST Repository

Yao, Yingbang; Chan, H. T.; Mak, C. L.; Wong, Kinhung

2013-01-01

. The phase transitions of the films were studied by Raman spectroscopy. Two distinct anomalies originating from the cubic-to-tetragonal (TC-T ~ 300 C) and tetragonal-to-orthorhombic (TT-O ~ 120 C) phase transitions were observed. Our results show that Raman

Spectroscopy of 215Ra: the shell model and enhanced E3 transitions

International Nuclear Information System (INIS)

Stuchbery, A.E.; Dracoulis, G.D.; Kibedi, T.; Fabricius, B.; Lane, G.J.; Poletti, A.R.; Baxter, A.M.

1998-01-01

Excited states in the N=127 nucleus 215 Ra have been studied using γ-ray and electron spectroscopy following reactions of 13 C on 206 Pb targets. Levels were identified up to spins of ∝61/2 ℎ and excitation energies of ∝6 MeV. Enhanced octupole transitions are a feature of the level scheme. Lifetimes and magnetic moments were measured for several isomeric levels. The level scheme, transition rates and magnetic moments are compared with empirical shell model calculations and multiparticle octupole-coupled shell model calculations. In general, the experimental data are well described, but in comparison with its success in describing enhanced E3 transitions between related states in the radon isotopes, some limitations of the multiparticle octupole-coupling approach are revealed in 215 Ra. (orig.)

KL→π0e+e- in the standard model with a heavy top quark

International Nuclear Information System (INIS)

Flynn, J.M.

1989-07-01

We consider the theoretical predictions for the decay K L → π 0 e + e - in the standard model with a heavy top quark. Theoretically, the decay is interesting because we may be able to see a CP violating amplitude. However, there are three competing pathways for the decay. The leading electromagnetic process is through a π 0 γ - intermediate state in a total angular momentum zero, and hence CP even, configuration. Since K L is mostly CP odd, K L ∼ K 1 + εK 2 , this one-photon process violates CP either directly, when the CP odd component decays, or indirectly through the decay of the small CP even component. The higher order electromagnetic process, K L → π 0 γγ → π 0 e + e - , can be competitive in rate, since it can proceed without CP violation. The theoretical estimates of these three competing mechanisms are discussed. We will show all three contributions could give rise to a branching ratio for K L → π 0 e + e - which is at most of order 10 -11 . (author)

Regular-chaos transition of the energy spectrum and electromagnetic transition intensities in 44V nucleus using the framework of the nuclear shell model

International Nuclear Information System (INIS)

Hamoudi, A.K.; Abdul Majeed Al-Rahmani, A.

2012-01-01

The spectral fluctuations and the statistics of electromagnetic transition intensities and electromagnetic moments in 44 V nucleus are studied by the framework of the interacting shell model, using the FPD6 as a realistic effective interaction in the isospin formalism for 4 particles move in the fp-model space with a 40 Ca core. To look for a regular-chaos transition in 44 V nucleus, we perform shell model calculations using various interaction strengths β to the off-diagonal matrix elements of the FPD6. The nearest-neighbors level spacing distribution P(s) and the distribution of electromagnetic transition intensities [such as, B(M1) and B(E2) transitions] are found to have a regular dynamic at β=0, a chaotic dynamic at β⩾0.3 and an intermediate situation at 0 3 statistic we have found a regular dynamic at β=0, a chaotic dynamic at β⩾0.4 and an intermediate situation at 0<β<0.4. It is also found that the statistics of the squares of M1 and E2 moments, which are consistent with a Porter-Thomas distribution, have no dependence on the interaction strength β.

Influence of intermartensitic transitions on transport properties of Ni$_{2.16}Mn_{0.84}$Ga alloy

CERN Document Server

Khovailo, V V; Wedel, C; Takagi, T; Abe, T; Sugiyama, K

2004-01-01

Magnetic, transport, and x-ray diffraction measurements of ferromagnetic shape memory alloy Ni$_{2.16}$Mn$_{0.84}$Ga revealed that this alloy undergoes an intermartensitic transition upon cooling, whereas no such a transition is observed upon subsequent heating. The difference in the modulation of the martensite forming upon cooling from the high-temperature austenitic state [5-layered (5M) martensite], and the martensite forming upon the intermartensitic transition [7-layered (7M) martensite] strongly affects the magnetic and transport properties of the alloy and results in a large thermal hysteresis of the resistivity $\\rho$ and magnetization $M$. The intermartensitic transition has an especially marked influence on the transport properties, as is evident from a large difference in the resistivity of the 5M and 7M martensite, $(\\rho_{\\mathrm{5M}} - \\rho_{\\mathrm{7M}})/\\rho _{\\mathrm{5M}} \\approx 15%$, which is larger than the jump of resistivity at the martensitic transition from the cubic austenitic phase ...

Gigantic perpendicular magnetic anisotropy of heavy transition metal cappings on Fe/MgO(0 0 1)

Science.gov (United States)

Taivansaikhan, P.; Odkhuu, D.; Rhim, S. H.; Hong, S. C.

2017-11-01

Effects of capping layer by 5d transition metals (TM = Hf, Ta, W, Re, Os, Ir, Pt, and Au) on Fe/MgO(0 0 1), a typical magnetic tunneling junction, are systematically investigated using first-principles calculation for magnetism and magnetocrystalline-anisotropy (MCA). The early TMs having less than half-filled d bands favor magnetization antiparallel to Fe, whereas the late TMs having more than half-filled d bands favor parallel, which is explained in the framework of kinetic exchange energy. The Os capping, isovalent to Fe, enhances MCA significantly to gigantic energy of +11.31 meV/cell, where positive contribution is mostly from the partially filled majority d bands of magnetic quantum number of |m| = 1 along with stronger spin-orbit coupling of Os than Fe. Different TM cappings give different MCA energies as the Fermi level shifts according to the valence of TM: Re and Ir, just one valence more or less than Os, have still large PMCA but smaller than the Os. In the W and Pt cappings, valence difference by two, PMCA are further reduced; MCAs are lowered compared to Fe/MgO(0 0 1) by the cappings of the very early TMs (Hf and Ta), while the very late TM (Au) switches sign to in-plane MCA.

Absolute Transition Rates in {sup 188}lr

Energy Technology Data Exchange (ETDEWEB)

Malmskog, S G; Berg, V

1969-09-15

Half-lives of several excited levels in {sup 188}lr have been measured using an electron-electron delayed coincidence spectrometer. Active {sup 188}Pt sources were prepared from spallation products using the ISOLDE on-line mass separator facility at CERN. The following half-lives were obtained: T{sub 1/2} (54.8 keV level) = (1.93 {+-} 0.10) nsec; T{sub 1/2} (96.7 keV level) = (0.59 {+-} 0.12) nsec; T{sub 1/2} (187.6 keV level) = (0.056 {+-} 0.013) nsec; T{sub 1/2} (195.1 keV level) = (0.051 {+-} 0.010) nsec; T{sub 1/2} (478. 3 keV level) {<=} 0.15 nsec The 54.8 keV transition was found to have an enhanced E2 transition probability indicating a collective character for this transition.

Angular analysis of the $B^0 \\to K^{*0} e^+ e^-$ decay in the low-$q^2$ region at LHCb

CERN Multimedia

Borsato, Martino

2015-01-01

An angular analysis of the $B^0 \\rightarrow K^{*0} e^+ e^-$ decay is performed using a data sample, corresponding to an integrated luminosity of 3.0${\\mbox {fb}^{-1}}$, collected by the LHCb experiment in $pp$ collisions at centre-of-mass energies of 7 and 8 TeV during 2011 and 2012. For the first time several observables are measured in the dielectron mass squared ($q^2$) interval between 0.002 and 1.120${\\mathrm{\\,Ge\\kern -0.1em V^2\\!/}c^4}$. The angular observables $F_{\\mathrm{L}}$ and $A_{\\mathrm{T}}^{\\mathrm{Re}}$ which are related to the \\Kstarz polarisation and to the lepton forward-backward asymmetry, are measured to be $F_{\\mathrm{L}}= 0.16 \\pm 0.06 \\pm0.03$ and $A_{\\mathrm{T}}^{\\mathrm{Re}} = 0.10 \\pm 0.18 \\pm 0.05$, where the first uncertainty is statistical and the second systematic. The angular observables $A_{\\mathrm{T}}^{(2)}$ and $A_{\\mathrm{T}}^{\\mathrm{Im}}$ which are sensitive to the photon polarisation in this $q^2$ range, are found to be $A_{\\mathrm{T}}^{(2)} = -0.23 \\pm 0.23 \\pm...

Transverse susceptibility as a probe of the magnetocrystalline anisotropy-driven phase transition in Pr0.5Sr0.5CoO3

Science.gov (United States)

Frey Huls, N. A.; Bingham, N. S.; Phan, M. H.; Srikanth, H.; Stauffer, D. D.; Leighton, C.

2011-01-01

Half-doped Pr1-xSrxCoO3 (x=0.5) displays anomalous magnetism, most notably manifest in the field-cooled magnetization versus temperature curves under different applied cooling fields. Recently, an explanation was advanced that a magnetocrystalline anisotropy transition driven by a structural transition at 120 K is the origin of this behavior. In this paper, we further elucidate the nature of the magnetic anisotropy across the low-temperature phase transition in this material by means of transverse susceptibility (TS) measurements performed using a self-resonant tunnel diode oscillator. TS probes magnetic materials by means of a small radio frequency oriented transverse to a dc field that sweeps from positive to negative saturation. TS scans as a function of field clearly reveal peaks associated with the anisotropy (HK) and switching fields (HS). When peak position is examined as a function of temperature, ˜120 K the signature of a ferromagnetic-to-ferromagnetic phase transition is evident as a sharp feature in HK and a corresponding cusp in HS. A third TS peak (not previously observed in other classes of magnetic oxides such as manganites and spinel ferrites) is found to be correlated with the crossover field (Hcr) in the unconventional magnetization versus temperature [M(T)] behavior. We observe a strong temperature dependence of Hcr at ˜120 K using this technique, which suggests the magnetic-field-influenced magnetocrystalline anisotropy transition. We show the switching between the high-field magnetization state and the low-field magnetization state associated with the magnetocrystalline anisotropy transition is irreversible when the magnetic field is recycled. Finally, we demonstrate that the TS peak magnitude indicates easy axis switching associated with this phase transition, even in these polycrystalline samples. Our results further confirm that TS provides new insights into the magnetic behavior of complex oxides.

LMS and E-learning 2.0. A Second Life for E-learning

Directory of Open Access Journals (Sweden)

Eng. Cosmin Olteanu

2008-12-01

Full Text Available E-learning 2.0 is a consequence of evolving into Web 2.0. Therefore we can say that Web2.0 : is defined as the “read-write” web which provides all the services and applications to allow individualsto co-create content, collaborate and share it with others that supports user-generated content, that is contentcreated by “users”, rather than specialist authors or publishers using a variety of affordable technologieslike blogs, podcasts and wikis. E-learning 2.0 is about creating and sharing information and knowledgewith others and is about using blogs, wikis, social bookmarking and social networks within an educationalor training context to support a new collaborative approach to learning.

Pure E2 transitions: A test for BRICC Internal Conversion Coefficients

International Nuclear Information System (INIS)

Gerl, J.; Sai, K. Vijay; Sainath, M.; Gowrishankar, R.; Venkataramaniah, K.

2009-01-01

The most widely used theoretical internal conversion coefficient (ICC) tables are of Hager and Seltzer (HS), Rosel et al. and BRICC (Band et al. tables using BRICC interpolation code). A rigorous comparison of experimental ICCs with various theoretical tabulations is possible only when a large data on experimental ICCs is available at one place. For this reason, a compilation of all the available experimental ICCs, α T , α K , α L of E2 transitions for a number of elements in the range of 24≤Z≤94 is presented. Listing of experimental data includes 595 datasets corresponding to 505 E2 transitions in 165 nuclei across the nuclear chart. Data with less than 10% experimental uncertainty have been selected for comparison with the theoretical values of Hager and Seltzer, Rosel et al. and BRICC. The relative percentage deviation (%Δ) have been calculated for each of the above theories and the average (%Δ) are estimated. The Band et al. tables, using the BRICC interpolation code are seen to give theoretical ICCs closest to experimental values.

Observability of B0 - B vector0 mixing in the e+e- → BB vector X reaction at √s approx. = 15 - 30 GeV

International Nuclear Information System (INIS)

Fridman, A.; Schwarz, A.

1985-01-01

The possibility of observing mixing in the B 0 B vector B 0 system has been rather widely discussed. In particular theoretical estimates have been made for the case of B 0 B vector 0 production in the e + e - → upsilon (4S) → B 0 B vector 0 reaction. Mixing in this specific channel is expected to appear as a small effect and might thus be hardly measurable. Here the authors will therefore consider the e + e - → BB vector X reaction (X meaning anything well above the BB vector threshold where any combination of BB vector mesons (B/sub u/B vector/sub u/, B/sub u/B vector/sub d/, B/sub u/B vector/sub s/, etc.) can be produced. This reaction might be advantageous as mixing is expected to be almost complete for the B/sub s/ mesons. In this respect the study of mixing effects in the e + e - → BB vector X reaction is complementary to that in the e + e - → upsilon (4S) → B/sub d/ 0 B vector /sub e/ 0 process. In Section B.2 the authors recall briefly the parameters used to describe the BB vector mixing and in Section B.3 they give estimates for the mixing effects which could be observed in the e + e - → BB vector X reaction as well as in the upsilon (4S) decays. The authors have also evaluated the influence of a non-spectator component in the B-decay on the observability of the mixing phenomenon. Finally, in Section B.4 they give estimates for the number of signal and background events which could be observed in an e + e - experiment with an accumulated luminosity of 1000 pb -1 . 33 references, 4 figures

Two neutrino double-β decay of 94 ≤ A ≤ 150 nuclei for the 0{sup +} → 2{sup +} transition

Energy Technology Data Exchange (ETDEWEB)

Singh, Yash Kaur; Chandra, R. [Babasaheb Bhimrao Ambedkar University, Department of Applied Physics, Lucknow (India); Raina, P.K. [Indian Institute of Technology, Department of Physics, Ropar, Rupnagar (India); Rath, P.K. [University of Lucknow, Department of Physics, Lucknow (India)

2017-12-15

Within the PHFB approach, the 0{sup +} → 2{sup +} transition of two neutrino double-β decay of {sup 94,96}Zr, {sup 100}Mo, {sup 104}Ru, {sup 110}Pd, {sup 128,130}Te and {sup 150}Nd isotopes is studied employing wave functions generated with four different parametrizations of the pairing plus multipole type of two-nucleon interaction and the summation method. In comparison to the 0{sup +} → 0{sup +} transition, the nuclear transition matrix elements M{sub 2ν} (2{sup +}) are quite sensitive to the deformation of the yrast 2{sup +} state. Consideration of the available theoretical and experimental results suggests that the observation of the 0{sup +} → 2{sup +} transition of 2νβ{sup -}β{sup -} decay may be possible in {sup 96}Zr, {sup 100}Mo, {sup 130}Te and {sup 150}Nd isotopes. The effect of deformation on the M{sub 2ν} (2{sup +}) is also studied. (orig.)

Micro-Raman scattering and dielectric investigations of phase transitions behavior in the PbHf0.7Sn0.3O3 single crystal

Science.gov (United States)

Jankowska-Sumara, Irena; Ko, Jae-Hyeon; Podgórna, Maria; Oh, Soo Han; Majchrowski, Andrzej

2017-09-01

Raman light scattering was used to detect the sequence of transitions in a PbHf1-xSnxO3 (PHS) single crystal with x = 0.30 in a temperature range of 77-873 K. Changes of Raman spectra were observed in the vicinity of structural phase transitions: between the antiferroelectric (AFE1)-antiferroelectric (AFE2)—intermediate—paraelectric phases. Light scattering and dielectric investigations were used to find out the nature and sequence of the phase transition, as well as the large dielectric permittivity values measured at the phase transition, by searching for the soft-phonon-mode behavior. The experimentally recorded spectra were analyzed in terms of the damped-harmonic oscillator model for the phonon bands. It is demonstrated that the structural phase transformations in PHS can be considered as the result of softening of many modes, not only the ferroelectric one. It was also proved that locally broken symmetry effects are present at temperatures far above the Curie temperature and are connected with the softening of two optic modes of different nature.

Allowed and forbidden transition parameters for Fe XV

International Nuclear Information System (INIS)

Nahar, Sultana N.

2009-01-01

A comprehensive set of fine structure energy levels, oscillator strengths (f), line strengths (S), and radiative decay rates (A) for bound-bound transitions in Fe XV is presented. The allowed electric dipole (E1) transitions were obtained from the relativistic Breit-Pauli R-matrix method which is based on the close coupling approximation. A total of 507 fine structure energy levels with n ≤ 10, l ≤ 9, and 0 ≤ J ≤ 10 are found. They agree within 1% with the available observed energies. These energy levels yield a total of 27,812 E1, same-spin multiplets and intercombination transitions. The A values are in good agreement with those compiled by NIST and other existing values for most transitions. Forbidden transitions are obtained from a set of 20 configurations with orbitals ranging from 1s to 5f using the relativistic code SUPERSTRUCTURE (SS) in the Breit-Pauli approximation. From a set of 123 fine structure levels, a total of 6962 S and A values are presented for forbidden electric quadrupole (E2), electric octupole (E3), magnetic dipole (M1), and magnetic quadrupole (M2) transitions. The energies from SS calculations agree with observed energies to within 1-3%. A values for E2, M1 transitions agree very well with the available values for most transitions while those for M2 transitions show variable agreement. The large set of transition parameters presented should be applicable for both diagnostics and spectral modeling in the X-ray, ultraviolet, and optical regions of astrophysical plasmas.

Merging different interactivity perspectives: 1.0 and 2.0 frameworks = Combinando diferentes perspectivas de interatividade: estruturas 1.0 e 2.0

Directory of Open Access Journals (Sweden)

Taddeo, Gabriella

2009-01-01

Full Text Available Meu objetivo neste trabalho é apresentar uma análise do conceito de interatividade audiovisual e sua evolução em relação à web 2. 0 e à cultura participativa. Um breve referencial teórico sobre o conceito de interatividade e sua evolução nas últimas décadas será seguido por uma análise do conceito tradicional de interatividade baseado em uma relação usuário-meio fechada. Ao final vou ainda articular a minha reflexão sobre novas formas de interatividade que se baseiam em um modelo mais participativo no qual os usuários interagem entre si e criam comunidades dentro e através dos ambientes de mídia interativos. Utilizando o referencial teórico de Thompson (1995 sobre interação mediada, meu objetivo será definir como novas estratégias participativas da TV 2. 0 estão criando não apenas novas formas de conteúdo e de linguagem, como também "interações quase-mediadas" entre produtores de mídia e seu público. Esses ambientes são, então, caracterizados por um diálogo indireto e uma complexa competição para o domínio do imaginário midiático

E-Learning 3.0 = E-Learning 2.0 + Web 3.0?

Science.gov (United States)

Hussain, Fehmida

2012-01-01

Web 3.0, termed as the semantic web or the web of data is the transformed version of Web 2.0 with technologies and functionalities such as intelligent collaborative filtering, cloud computing, big data, linked data, openness, interoperability and smart mobility. If Web 2.0 is about social networking and mass collaboration between the creator and…

Quenching of spin-flip quadrupole transitions

International Nuclear Information System (INIS)

Castel, B.; Blunden, P.; Okuhara, Y.

1985-01-01

An increasing amount of experimental data indicates that spin-flip quadrupole transitions exhibit quenching effects similar to those reported earlier in (p,n) reactions involving l = 0 and l = 1 transitions. We present here two model calculations suggesting that the E2 spin-flip transitions are more affected than their M1 and M3 counterparts by the tensor and spin-orbit components of the nuclear force and should exhibit the largest quenching. We also review the experimental evidence corroborating our observations

Investigation of characteristics of sup 2 sup 0 sup 1 Tl -> sup 2 sup 0 sup 1 Hg

CERN Document Server

Kharitonov, V V

2002-01-01

The estimated intensities of transitions on the ground and first-excited levels in the sup 2 sup 0 sup 1 Hg at the decay of sup 2 sup 0 sup 1 Tl and estimated constants lg ft are obtained from the analysis of the relative intensities of the mercury M sub 4 N sub 6 sub , sub 7 N sub 6 sub , sub 7 Auger-electron line, initiated by the e-capture and of the conversion O sub 3 -mercury line, due to the nuclear transition with the energy 1.56 keV

Measurements on the rare decay π0→e+e-

International Nuclear Information System (INIS)

Doesburg, W. van.

1981-01-01

In this thesis the first results of measurements on the rare decay of the neutral pion π 0 →e + e - are described. These measurements were performed in a collaboration at the European Organisation for Nuclear Research (CERN) in Geneva, using the OMICRON spectrometer. A negative pion beam of T=190 MeV produced neutral pions via the charge exchange reaction π - p→π 0 n in a liquid hydrogen target placed inside this spectrometer. The tracks of the incoming pions and any decay leptons emerging from the target were localized using multiwire proportional and drift chamber detectors. In the analysis, the momentum of a particle was then obtained from the curvature of its track and the values of the magnetic field along that track. The magnetic field was accurately measured throughout the volume of the spectrometer. (Auth.)

Microscopic Structure of DX Centers in Cd0.8Zn0.2Te:Cl

International Nuclear Information System (INIS)

Shan, Y.Y.; Lynn, K.G.; Szeles, C.; Asoka-Kumar, P.; Thio, T.; Bennett, J.W.; Beling, C.B.; Fung, S.; Becla, P.

1997-01-01

Photoexcitation of chlorine DX centers induces a transition of the Cl atoms to the shallow-donor state and persistent photoconductivity at low temperature in Cd 0.8 Zn 0.2 Te:Cl. The relaxation of the substitutional Cl atoms to the DX state at 140K is coincident with a decrease of the positron line-shape parameter and an increase of annihilation with high-momentum core electrons. The results indicate positron trapping and annihilation at DX centers and at chlorine A centers. The data support the bond breaking model of the DX centers and the outward relaxation of the Cl and Cd(Zn) atoms along the [111] direction. The thermal barrier for the shallow-deep transition was found to be 0.44eV. copyright 1997 The American Physical Society

A Solvable Model for Nuclear Shape Phase Transitions

International Nuclear Information System (INIS)

Levai, G.; Arias, J. M.

2009-01-01

There has been considerable interest recently in phase transitions that occur between some well-defined nuclear shapes, e.g. the spherical vibrator, the axially deformed rotor and the γ-unstable rotor, which are assigned to the U(5), SU(3) and 0(6) symmetries. These shape phase transitions occur through critical points of the IBM phase diagram and correspond to rapid structural changes. The first transition of this type describes transition form the spherical to the γ-unstable phase and has been associated with an E(5) symmetry. Later further critical point symmetries e.g. X(5) and Y(5) have also been proposed for transitions between other nuclear shape phases. In another application the chain of even Ru isotopes was considered from A 98 to 112 [2]. The parameters were extracted from a fit to the low-lying energy spectrum of each nucleus and were used to plot the corresponding potential. It was found that up to A =102 the potential is essentially an harmonic oscillator, while at A =104 a rather flat potential was seen, in accordance with the expected phase transition and E(5) symmetry there. With increasing A then the minimum got increasingly deeper and moved away from β = 0. We discuss the possibility of generalizing the formalism in two ways: first by including dependence on the 7 variable allowing for the approximate description of nuclei close to the X(5) symmetry, and second, including higher-lying energy levels in the quasi-exactly solvable formalism

Magnetic properties of zigzag (0,9 GaAs nanotube doped with 3d transition metals

Directory of Open Access Journals (Sweden)

R Fathi

2016-06-01

Full Text Available of 3d transition metals (Sc, Ti, Cr, Mn , Fe, Co, Ni in both far and close situations were studied based on spin polarised density functional theory using the generalized gradient approximation (LDA with SIESTA code. The electronic structures show that zigzag (0,9 GaAs nanotubes are non-magnetic semiconductors with direct band gap. It was revealed that doping of 11.11 % Fe and Mn concentrations substituted in Ga sites in ferromagnetic phase in far situation and Cr sites in ferromagnetic phase in near situation introduces half metallic behavior with %100 spin polarization. The unique structure of spin polarised energy levels is primarily attributed to strong hybridization of 3d transition metal and its nearest-neighbor As-4p orbitals. The results of this study can be useful for empirical studies on diluted magnetic semiconductors (DMSs and systemic investigation in 3d transitional metals. We suggest that GaAs nanotubes doped by transition metals would have a potential application as a spin polarised electron source for spintronic devices in the future.

Collective vector method for calculation of E1 moments in atomic transition arrays

International Nuclear Information System (INIS)

Bloom, S.D.; Goldberg, A.

1985-10-01

The CV (collective vector) method for calculating E1 moments for a transition array is described and applied in two cases, herein denoted Z26A and Z26B, pertaining to two different configurations of iron VI. The basic idea of the method is to create a CV from each of the parent (''initial state'') state-vectors of the transition array by application of the E1 operator. The moments of each of these CV's, referred to the parent energy, are then the rigorous moments for that parent, requiring no state decomposition of the manifold of daughter state-vectors. Since, in cases of practical interest, the daughter manifold can be orders of magnitude larger in size than the parent manifold, this makes possible the calculation of many moments higher than the second in situations hitherto unattainable via standard methods. The combination of the moments of all the parents, with proper statistical weighting, then yields the transition array moments from which the transition strength distribution can be derived by various procedures. We describe two of these procedures: (1) The well-known GC (Gram-Charlier) expansion in terms of Hermite polynomials, (2) The Lanczos algorithm or Stieltjes imaging method, also called herein the delta expansion. Application is made in the cases of Z26A (50 lines) and Z26B (5523 lines) and the relative merits and shortcomings of the two procedures are discussed. 10 refs., 15 figs., 2 tabs

Study of the variation of the E-I curves in the superconducting to normal transition of Bi-2212 textured ceramics by Pb addition

Directory of Open Access Journals (Sweden)

Sotelo, A.

2006-06-01

Full Text Available Vitreous cylinders with compositions Bi2-xPbxSr2CaCu2Oy, (x = 0, 0.2, 0.4 and 0.6 were prepared and used as precursors to fabricate textured bars through a laser floating zone melting method (LFZ. The resulting textured cylindrical bars were annealed, followed by their electrical characterization. The microstructure was determined and correlated with the electrical measured properties. The influence of Pb doping on the sharpness of the superconducting to normal transition on the E-I curves has been determined. The sharpest transitions have been obtained for samples doped with 0.4Pb.

Se han preparado precursores de tipo vítreo en forma de cilindro con composiciones nominales Bi2-xPbxSr2CaCu2Oy, con x = 0, 0.2, 0.4 y 0.6. Estos cilindros se han utilizado como precursores para fabricar barras texturadas por medio de una técnica de fusión zonal inducida por láser (LFZ. Estas barras texturadas se recocieron a diferentes temperaturas y se caracterizaron eléctricamente. Además, se examinó su microestructura para correlacionarla con las propiedades eléctricas medidas. La variación de la transición del estado superconductor al normal se ha relacionado con el dopaje con Pb a través de las curvas E-I. Las mejores transiciones se han obtenido para muestras dopadas con 0.4 Pb.

Neutrino interactions with e+μ- and multiple K0's

International Nuclear Information System (INIS)

Stevenson, M.L.

1976-07-01

A scan for directly produced positrons in 5,000 neutrino interactions in the neon (21 percent) hydrogen filled bubble chamber at Fermilab has yielded 15 events, 9 of which have μ - 's identified in the external muon identifier. On correcting for detection efficiency one obtains sigma(e + μ - )/sigma(μ - ) approximately 1 x 10 -2 for E/sub e + / > .8 GeV and E/sub ν/ > 5 GeV. The kaon multiplicity is unexpectedly high. Eleven of the events have one or more Vees and three have two or more. Among the 11 events are two clear Λ's and two ambiguous K 0 /Λ. There are four events with identifiable charged kaons. A 16th e + event (9) is a definite ν/sub e/. From this information one concludes that the kaon multiplicity is 2 +- .6 K 0 's and 2 +- 1 K +- 's per interaction. From the observation - />/ + /> = 6.6, one concludes that the e + 's are probably not uniquely from heavy lepton decay. From a variety of analyses involving the e + and/or K 0 's one learns that the mass of the hadron (C) that produces the e + 's is greater than 1.6 GeV. By determining the fraction of normal charged current (CC) events that have K 0 /sub s/ → π + π - one is able to compare this fraction with the fraction of CC events that have e + μ - (K 0 /sub s/ → π + π - ) to establish a conservative lower limit to the semileptonic branching ratio, C → (e + and μ + ) ν/C → all > 0.33 (1 +- .42), provided that the same number of K 0 /sub s/ exists in thenonleptonic decays as in the semileptonic ones, and that the phase space for μ + and e + are nearly equal. There is no compelling evidence for an energy threshold and there is a hint of some neutral current events among the e + events

Temperature dependence of the dielectric tensor of monoclinic Ga2O3 single crystals in the spectral range 1.0-8.5 eV

Science.gov (United States)

Sturm, C.; Schmidt-Grund, R.; Zviagin, V.; Grundmann, M.

2017-08-01

The full dielectric tensor of monoclinic Ga2O3 (β-phase) was determined by generalized spectroscopic ellipsometry in the spectral range from 1.0 eV up to 8.5 eV and temperatures in the range from 10 K up to 300 K. By using the oriented dipole approach, the energies and broadenings of the excitonic transitions are determined as a function of the temperature, and the exciton-phonon coupling properties are deduced.

The photoluminescent property and optical transition analysis of host sensitized Ca{sub 0.5}Sr{sub 0.5}MoO{sub 4}:Dy{sup 3+} phosphor

Energy Technology Data Exchange (ETDEWEB)

Yang, Zhiping; Hou, Chuncai [College of Physics and Technology, Hebei University, Baoding, Hebei 071002 (China); Duan, Guangjie [College of Electronics and Information Engineering, Hebei University, Baoding, Hebei 071002 (China); Yang, Fu [College of Physics and Technology, Hebei University, Baoding, Hebei 071002 (China); College of Science, Hebei North University, Zhangjiakou 075000 (China); Liu, Pengfei; Wang, Can [College of Physics and Technology, Hebei University, Baoding, Hebei 071002 (China); Liu, Lipeng [College of Electronics and Information Engineering, Hebei University, Baoding, Hebei 071002 (China); Dong, Guoyi, E-mail: dongguoyitxzz@163.com [College of Physics and Technology, Hebei University, Baoding, Hebei 071002 (China)

2014-08-01

Highlights: • A novel host sensitized Ca{sub 0.5−x}Sr{sub 0.5}MoO{sub 4}:xDy{sup 3+} phosphors could be synthesized by solid state reaction. • The XRD and SEM figures were made to analyze the crystal phase and morphology of Ca{sub 0.5−x}Sr{sub 0.5}MoO{sub 4}:xDy{sup 3+} phosphors. • We research the emission and excitation properties by analyzing the relevant optical transition. • The energy transition is proved to exist by the analysis on luminescence spectra and luminescence decay curves. • The chromaticity coordinate of Ca{sub 0.5−x}Sr{sub 0.5}MoO{sub 4}:xDy{sup 3+} will be tunable as changing x. - Abstract: A series of Dy{sup 3+} doped Ca{sub 0.5}Sr{sub 0.5}MoO{sub 4} phosphors were synthesized by solid state reaction. The structure and the photoluminescent (PL) properties of the as-prepared powders were characterized by X-ray diffraction (XRD), field emission scanning electron microscope and fluorescent spectrophotometry. The analyses on optical transition of Ca{sub 0.5}Sr{sub 0.5}MoO{sub 4}:xDy{sup 3+} phosphors indicate that the broad band of excitation spectrum comes from the charge transmission. The broad band of excitation spectrum matches well with the excitation energy level of Dy{sup 3+}, indicating the energy transfer from the host to Dy{sup 3+}. The chromaticity coordinates changed from blue–green to yellow area depending on the Dy{sup 3+} concentration. In addition, the main mechanism of the concentration quenching was the electric multiple interaction between Dy{sup 3+} ions.

Unconventional phase transitions in liquid crystals

Science.gov (United States)

Kats, E. I.

2017-12-01

According to classical textbooks on thermodynamics or statistical physics, there are only two types of phase transitions: continuous, or second-order, in which the latent heat L is zero, and first-order, in which L ≠ 0. Present-day textbooks and monographs also mention another, stand-alone type—the Berezinskii-Kosterlitz-Thouless transition, which exists only in two dimensions and shares some features with first- and second-order phase transitions. We discuss examples of non-conventional thermodynamic behavior (i.e., which is inconsistent with the theoretical phase transition paradigm now universally accepted). For phase transitions in smectic liquid crystals, mechanisms for nonconventional behavior are proposed and the predictions they imply are examined.

Dielectric tensor of monoclinic Ga2O3 single crystals in the spectral range 0.5–8.5 eV

Directory of Open Access Journals (Sweden)

C. Sturm

2015-10-01

Full Text Available The dielectric tensor of Ga2O3 in the monoclinic (β phase was determined by generalized spectroscopic ellipsometry in a wide spectral range from 0.5 eV to 8.5 eV as well as by density functional theory calculations combined with many-body perturbation theory including quasiparticle and excitonic effects. The dielectric tensors obtained by both methods are in excellent agreement with each other and the observed transitions in the dielectric function are assigned to the corresponding valence bands. It is shown that the off-diagonal element of the dielectric tensor reaches values up to |εxz| ≈ 0.30 and cannot be neglected. Even in the transparent spectral range where it is quite small (|εxz| < 0.02 it causes a rotation of the dielectric axes around the symmetry axis of up to 20°.

Temperature dependent polarization reversal mechanism in 0.94(Bi1/2Na1/2)TiO3-0.06Ba(Zr0.02Ti0.98)O3 relaxor ceramics

Science.gov (United States)

Glaum, Julia; Simons, Hugh; Hudspeth, Jessica; Acosta, Matias; Daniels, John E.

2015-12-01

The temperature at which the electric field induced long-range ordered ferroelectric state undergoes transition into the short-range ordered relaxor state, TF-R, is commonly defined by the onset of strong dispersion of the dielectric permittivity. However, this combined macroscopic property and structural investigation of the polarization reversal process in the prototypical lead-free relaxor 0.94(Bi1/2Na1/2)TiO3-0.06Ba(Zr0.02Ti0.98)O3 reveals that an applied electric field can trigger depolarization and onset of relaxor-like behavior well below TF-R. The polarization reversal process can as such be described as a combination of (1) ferroelectric domain switching and (2) a reversible phase transition between two polar ferroelectric states mediated by a non-polar relaxor state. Furthermore, the threshold fields of the second, mediated polarization reversal mechanism depend strongly on temperature. These results are concomitant with a continuous ferroelectric to relaxor transition occurring over a broad temperature range, during which mixed behavior is observed. The nature of polarization reversal can be illustrated in electric-field-temperature (E-T) diagrams showing the electric field amplitudes associated with different polarization reversal processes. Such diagrams are useful tools for identifying the best operational temperature regimes for a given composition in actuator applications.

Dynamics of the magneto structural phase transition in La(Fe{sub 0.9}Co{sub 0.015}Si{sub 0.085}){sub 13} observed by magneto-optical imaging

Energy Technology Data Exchange (ETDEWEB)

Kuepferling, M., E-mail: m.kuepferling@inrim.it; Basso, V. [Istituto Nazionale di Ricerca Metrologica (INRIM), Strada delle Cacce 91, 10135 Turin (Italy); Bennati, C. [Istituto Nazionale di Ricerca Metrologica (INRIM), Strada delle Cacce 91, 10135 Turin (Italy); Department of Applied Science and Technology, Politecnico di Torino, C.so Duca degli Abruzzi 24, 10129 Turin (Italy); Laviano, F.; Ghigo, G. [Department of Applied Science and Technology, Politecnico di Torino, C.so Duca degli Abruzzi 24, 10129 Turin (Italy)

2014-05-07

We investigate the temperature induced ferromagnetic to paramagnetic phase transition in Co substituted La(Fe{sub x}Co{sub y}Si{sub 1−x−y}){sub 13} with x = 0.9 and low Co content of y = 0.015 (T{sub c}≃200 K) by means of magneto-optical imaging with indicator film and by calorimetry at very low temperature rates. We were able to visualize the motion of the ferromagnetic (FM)/paramagnetic (PM) front which is forming reproducible patterns independently of the temperature rate. The average velocity of the FM/PM front was calculated to be 10{sup −4} m/s during the continuous propagation and 4×10{sup −3} m/s during an avalanche. The heat flux was measured at low temperature rates by a differential scanning calorimeter and shows a reproducible sequence of individual and separated avalanches which occurs independently of the rate. We interpret the observed effects as the result of the athermal character of the phase transition.

Potential and Barriers to Adoption of B2B E-Commerce in SMEs in Transition Economies: Case of Albania

OpenAIRE

Narasimha Rao Vajjhala; Salu George Thandekkattu

2017-01-01

Small- and Medium-sized Enterprises (SMEs) can benefit significantly from investments in e-commerce and e-business. However, the adoption of e-commerce has been quite slow and limited among SMEs, especially in transition economies. Interviews were conducted with senior managers from 30 medium-sized enterprises in a transition economy – Albania, three from each of the ten key sectors, namely, information and communication technology (ICT), tourism, banking, financial servi...

Protection against an infectious disease by enterohaemorrhagic E. coli 0-157.

Science.gov (United States)

Ota, A

1999-07-01

Preventive measures against infection by enterohaemorrhagic E. coli 0-157 are described. Eating yoghurt and Kefir supposedly induces more bifid bacteria and lactic acid bacteria to colonize in the intestines, thereby protecting humans from infection by E. coli 0-157. Some foods, such as plum extract, act as a mild antibiotic and produce an acidic environment within the intestine, thus interfering with growth of the E. coli 0-157. The natural colonization of harmless E. coli or other bacteria that are more powerful than E. coli 0-157 can possibly protect against infection. A vaccination against E. coli 0-157 H7 may also be effective. In addition, it has been suggested that the correct levels of nitric oxide and calcium in the blood may activate immunity and protect against infection by E. coli 0-157.

Performance of transition metal-carbon multilayer mirrors from 80 to 350 eV

International Nuclear Information System (INIS)

Kania, D.R.; Bartlett, R.J.; Trela, W.J.; Spiller, E.; Golub, L.

1984-03-01

We report measurements and theoretical calculations of the reflectivity and resolving power of multilayer mirrors made of alternate layers of a transition metal (Co, Fe, V, and Cr) and carbon (2d approx. = 140 A) from 80 to 350 eV

Second order magnetic phase transition and scaling analysis in iron doped manganite La{sub 0.7}Ca{sub 0.3}Mn{sub 1−x}Fe{sub x}O{sub 3} compounds

Energy Technology Data Exchange (ETDEWEB)

Ginting, Dianta [Department of Applied Physics and Institute of Natural Sciences, Kyung Hee University, Yong-in 446-701 (Korea, Republic of); Nanto, Dwi [Physics Education, Syarif Hidayatullah State Islamic University, Jakarta 15412 (Indonesia); Denny, Yus Rama [Department of Electrical Engineering, University of Sultan Ageng Tirtayasa, Banten 42435 (Indonesia); Tarigan, Kontan [Department of Mechanical Engineering, Mercu Buana University, Jakarta-Barat, Jakarta 11650 (Indonesia); Hadi, Syamsul [Department of Mechanical Engineering, State Polytechnic of Malang, East Java 65100 (Indonesia); Ihsan, Mohammad [PSTBM-BATAN, Kawasan Puspiptek Serpong, Tangerang Selatan, Banten 15314 (Indonesia); Institute of Electronic Materials, University of Wollongong, Wollongong NSW 2522 (Australia); Rhyee, Jong-Soo, E-mail: jsrhyee@khu.ac.kr [Department of Applied Physics and Institute of Natural Sciences, Kyung Hee University, Yong-in 446-701 (Korea, Republic of)

2015-12-01

We investigated magnetic properties of La{sub 0.7}Ca{sub 0.3}Mn{sub 1−x}Fe{sub x}O{sub 3} (x=0.09 and 0.11) compounds in terms of isothermal magnetization analysis and scaling behavior with various critical exponents. From the Landau theory of magnetic phase transition, we found that the paramagnetic to ferromagnetic phase transition in La{sub 0.7}Ca{sub 0.3}Mn{sub 1−x}Fe{sub x}O{sub 3} (x=0.09 and 0.11) compounds is the type of second order magnetic transition (SOMT), which contrary to the first order magnetic transition (FOMT) for low Fe-doped compounds (x<0.09) in previous reports. When we investigate the critical behavior of the compounds near T=T{sub c} by the modified Arrott plot, Kouvel–Fisher plots, and critical isothermal analysis, the estimated critical exponents β, γ, and δ are in between the theoretically predicted values for three-dimensional Heisenberg and mean-field interaction models. It is noteworthy that the scaling relations are obeyed in terms of renormalization magnetization m=ε{sup −β}M(H,ε) and renormalized field h=|ε|{sup β+γ}H. Temperature-dependent effective exponents β{sub eff} and γ{sub eff} correspond to the ones of disordered ferromagnets. It is shown that the magnetic state of the compounds is not fully described by the conventional localized-spin interaction model because the ferromagnetic interaction has itinerant character by increasing Fe-doping concentration. - Highlights: • The ferromagnetic phase transition is of second order in La{sub 0.7}Ca{sub 0.3}Mn{sub 1−x}Fe{sub x}O{sub 3}. • The critical exponents are in between the 3D Heisenberg and mean-field models. • The ferromagnetic interaction becomes more itinerant by Fe-doping.

E1 transitions in the Harari quark model

International Nuclear Information System (INIS)

Kamath, S.G.

1976-10-01

The radiative decays psi(3.684)→γchi(sup(3)P sub(J)) and chi(sup(3)Psub(J)→chipsi(3.1) have been analyzed within the framework of the Harari quark model. The spatial matrix elements describing these L=1 to L=0 transitions have been estimated from the A 2 (1310)→ chirho(770) mode by applying U(6) symmetry at the quark level. The resulting decay widths, which compare very well with experimental data, have subsequently been used to determine the SU(3)sub(H) assignments for the chi states

The nature of the Esub(v) + 0.23 eV and Esub(v) + 0.38 eV gamma-induced centres in Ge

International Nuclear Information System (INIS)

Pearton, S.J.; Tavendale, A.J.

1982-07-01

All p-type Ge grown by the Czochralski technique from silica crucibles under an H 2 atmosphere shows two dominant acceptor defects on γ irradiation. Measurements by DLTS are reported which support the hypothesis that these centres (Esub(v) + 0.23 eV, Esub(v) + 0.38 eV) are most likely due to complexes between oxygen and lattice vacancies

Spin dependence of intra-ground-state-band E2 transitions in the SU(3) limit of the sdg interacting boson model

Science.gov (United States)

Long, G. L.; Ji, H. Y.

1998-04-01

B(E2, L+2-->L) transitions in the sdg interacting boson model SU(3) limit are studied with a general E2 transition operator. Analytical expressions are obtained using a group theoretic method. It is found that when using transition operators of the form (d†g~+g†d~)2 or (g†g~)2, the B(E2, L+2-->L) values in the ground-state band have an L(L+3) dependent term. As L increases, the B(E2) values can be larger than the rigid rotor model value. Application to 236,238U is discussed.

Structural analysis, optical and dielectric function of [Ba{sub 0.9}Ca{sub 0.1}](Ti{sub 0.9}Zr{sub 0.1})O{sub 3} nanocrystals

Energy Technology Data Exchange (ETDEWEB)

Herrera-Pérez, G., E-mail: guillermo.herrera@cimav.edu.mx, E-mail: damasio.morales@cimav.edu.mx [Centro de Investigación en Materiales Avanzados (CIMAV), S. C. Miguel de Cervantes 120, Chihuahua 31136, Chihuahua (Mexico); Physics of Materials Department, Centro de Investigación en Materiales Avanzados (CIMAV), S. C. Miguel de Cervantes 120, Chihuahua 31136, Chihuahua (Mexico); Morales, D., E-mail: guillermo.herrera@cimav.edu.mx, E-mail: damasio.morales@cimav.edu.mx; Paraguay-Delgado, F.; Reyes-Rojas, A.; Fuentes-Cobas, L. E. [Physics of Materials Department, Centro de Investigación en Materiales Avanzados (CIMAV), S. C. Miguel de Cervantes 120, Chihuahua 31136, Chihuahua (Mexico); Borja-Urby, R. [Centro de Nanociencias Micro y Nanotecnologías, Instituto Politécnico Nacional, 07300 México City (Mexico)

2016-09-07

This work presents the identification of inter-band transitions in the imaginary part of the dielectric function (ε{sub 2}) derived from the Kramers–Kronig analysis for [Ba{sub 0.9}Ca{sub 0.1}](Ti{sub 0.9}Zr{sub 0.1})O{sub 3} (BCZT) nanocrystals synthesized by the modified Pechini method. The analysis started with the chemical identification of the atoms that conform BCZT in the valence loss energy region of a high energy-resolution of electron energy loss spectroscopy. The indirect band energy (E{sub g}) was determined in the dielectric response function. This result is in agreement with the UV-Vis technique, and it obtained an optical band gap of 3.16 eV. The surface and volume plasmon peaks were observed at 13.1 eV and 26.2 eV, respectively. The X-ray diffraction pattern and the Rietveld refinement data of powders heat treated at 700 °C for 1 h suggest a tetragonal structure with a space group (P4 mm) with the average crystal size of 35 nm. The average particle size was determined by transmission electron microscopy.

Evidence for a vortex-glass transition in superconducting Ba(Fe0.9Co0.1)2As2.

Science.gov (United States)

Prando, G; Giraud, R; Aswartham, S; Vakaliuk, O; Abdel-Hafiez, M; Hess, C; Wurmehl, S; Wolter, A U B; Büchner, B

2013-12-18

Measurements of magneto-resistivity and magnetic susceptibility were performed on single crystals of superconducting Ba(Fe0.9Co0.1)2As2 close to the conditions of optimal doping. The high quality of the investigated samples allows us to reveal dynamic scaling behaviour associated with a vortex-glass phase transition in the limit of a weak degree of quenched disorder. Accordingly, the dissipative component of the ac susceptibility is reproduced well within the framework of Havriliak-Negami relaxation, assuming a critical power-law divergence for the characteristic correlation time τ of the vortex dynamics. Remarkably, the random disorder introduced by the Fe1-xCox chemical substitution is found to act on the vortices as a much weaker quenched disorder than previously reported for cuprate superconductors such as Y1-xPrxBa2Cu3O7-δ.

Magnetic fluctuations near a quantum phase transition in CeCu5.9Au0.1

DEFF Research Database (Denmark)

Schröder, A.; Aeppli, G.; Bucher, E.

1998-01-01

We present inelastic cold neutron scattering measurements on a single crystal of the heavy-fermion compound CeCu5.9Au0.1, where non-Fermi-liquid behavior near a quantum phase transition was found in the specific heat and resistivity. This compound shows strongly correlated magnetic fluctuations......, most intense at wave vectors Q(1), near(1,0,0), close to the magnetic ordering vector found at higher Au-concentration. The energy dependence can be best described by a modified quasielastic Lorentzian with power alpha = 0.7. Down to the lowest temperature of 0.07 K the relaxation rate Gamma remains...

Hadronic Transitions from Upsilon (2S) to Upsilon (1s) and Upsilon Dipion Transitions at Energies Near the Upsilon (4S)

Science.gov (United States)

Kotoy, Sergei Anatolievich

This dissertation consists of two closely related analyses, both of which were performed using data collected with the CLEO II detector at the Cornell Electron Storage Ring. In the first analysis, using the world largest data sample of Υ(2 S) events, we have investigated the hadronic transitions between the Υ(2S) and the Υ(1S), i.e. decays of the Υ(2S) into the Υ(1S), plus a pair of pions ( p+p- or p0p0 ), a single η or a single p0 . The dipion transitions U(2S)-->U( 1S)pp were studied most closely, by using two different techniques: ``exclusive'' and ``inclusive''. In these measurements we determine the U(2S)-->U( 1S)pp branching ratios, and, by combining the exclusive and inclusive results, we derive the Υ(1S), leptonic branching ratios Bee and Bmm . Parameters of the ππ system in the dipion transitions (dipion invariant mass spectra, angular distributions) were analyzed and found to be consistent with current theoretical models. Lastly, we searched for the η and single π0 transitions and obtained upper limits on the branching ratios B(U(2S) -->U(1S)h ) and B(U(2S) -->U(1S)p 0) . In the second analysis, the data collected at the center of mass energies near the Υ(4S) were used to search for the dipion transition between pairs of Υ resonances. As a result of this search, we established upper limits on the branching ratios of the dipion transitions post='par'>p+p- and U(4S)-->U( 1S)p+p- , and measured the cross-sections for the radiative production of Υ(3 S) and Υ(2S) resonances e+e--->U(nS) g at the center of mass energies of Ecm = 10.58 GeV and Ecm = 10.52 GeV.

Structural and magnetic phase transitions in Pr.sub.0.15./sub.Sr.sub.0.85./sub.MnO.sub.3./sub. at high pressure

Czech Academy of Sciences Publication Activity Database

Kozlenko, D. P.; Dang, N.T.; Jirák, Zdeněk; Kichanov, S.E.; Lukin, E.V.; Savenko, B. N.; Dubrovinsky, L.S.; Lathe, C.; Martin, C.

2010-01-01

Roč. 77, č. 3 (2010), s. 407-411 ISSN 1434-6028 Institutional research plan: CEZ:AV0Z10100521 Keywords : high pressure * magnetic phase transitions Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 1.575, year: 2010

Effect of Cd doping on magnetocaloric effect and critical behavior analysis on perovskite Nd1-xCdxMnO3 (x = 0, 0.1, 0.2, 0.3, and 0.4) manganite polycrystals

Science.gov (United States)

Saravanan, C.; Thiyagarajan, R.; Manikandan, K.; Sathiskumar, M.; Kanjariya, P. V.; Bhalodia, J. A.; Arumugam, S.

2017-12-01

We report the doping effect of divalent cation Cd2+ at Nd-site of intermediate bandwidth manganite system NdMnO3 through the temperature- and magnetic field-dependent magnetization measurements. The parent compound shows paramagnetic-antiferromagnetic transition at 56 K, whereas Cd doped samples show the paramagnetic-ferromagnetic transition with fluctuating TC. During this transition, Nd1-xCdxMnO3 (x = 0.1 and 0.2) samples exhibit first order nature, whereas Nd1-xCdxMnO3 (x = 0.3 and 0.4) samples exhibit second order nature. It confirms a crossover from first order transition to second order transition while x = 0.2 to x = 0.3. By having first order transition, x = 0.2 sample exhibits high magnetic entropy change of 3.62 J kg-1 K-1 for the magnetic field change of 5 T out of all compositions. By having second order transitions, x = 0.4 sample exhibits a high relative cooling power of 319.71 J kg-1 for the magnetic field change of 5 T out of all the compositions. The critical behavior of second order transition of x = 0.3 and 0.4 samples has been analyzed using Arrott and Kouvel-Fisher plots. The estimated critical exponents of these samples are nearly matched with the mean free model, which can be explained by the existence of dipole-dipole interaction by the Cd doping which strengthens long range ferromagnetic interactions between the spins.

Dc transport and optical measurements on the charge-density-wave compounds (K,Rb){sub 0.3}(Mo,W)O{sub 3}

Energy Technology Data Exchange (ETDEWEB)

Al-Hadeethi, Ali Khairi Abdul-Qader

2013-04-26

The temperature dependence of the linear and the non-linear transport properties in K{sub 0.3}MoO{sub 3}, (K{sub 0.5}Rb{sub 0.5}){sub 0.3}MoO{sub 3}, and K{sub 0.3}Mo{sub 0.99}W{sub 0.01}O{sub 3} are presented. The temperature dependence of the dc resistivity of the pure sample has shown the Peierls metal-insulator phase transition at 180 K, where the transition is very sharp. The rubidium doping shifts the transition temperature to a lower temperature (170 K) and smears out the metal-insulator phase transition, i.e., the rubidium doping broadens the transition peak. Compared with the rubidium doping, the tungsten doping broadens the transition peak more and shifts the transition temperature to a lower temperature (140 K). The temperature-dependent dc resistivity curves of pure, Rb-doped, and W-doped blue bronze K{sub 0.3}MoO{sub 3} single crystals are analyzed in terms of the pseudogap just above TP and the Peierls energy gap below TP. The non-linear transport properties of pure, Rb-doped, and W-doped blue bronze K{sub 0.3}MoO{sub 3} single crystals have shown a nonlinear conductivity due to an incoherent CDW sliding, when the applied electric field exceeds the first threshold field (E{sub T}). Furthermore, above a second threshold field (E{sub T}{sup *} > E{sub T}) a coherent CDW-sliding sets in. For all studied samples, we find a monotonic increase of E{sub T} and E{sub T}{sup *} with decreasing temperature. This finding is discussed mainly in terms of the incommensurate-commensurate transition of the CDW. The coherent and incoherent CDW movements are discussed within the frame of the Fukuyama-Lee-Rice model.

Photon Echoes in the 3P0 ← 3H4 Transition of Pr3+/LaF3

NARCIS (Netherlands)

Morsink, Jos B.W.; Wiersma, Douwe A.

1979-01-01

Photon-echo quantum beats observed in the two-pulse and three-pulse photon echo of the 3P0 ← 3H4 transition in Pr3+/LaF3 were used to determine the excited-state spin-hamiltonian. In addition we report on the anomalous stimulated photon echo observed in the same transition which in a magnetic field

Surpassing the Theoretical 1-Norm Phase Transition in Compressive Sensing by Tuning the Smoothed L0 Algorithm

DEFF Research Database (Denmark)

Oxvig, Christian Schou; Pedersen, Patrick Steffen; Arildsen, Thomas

2013-01-01

Reconstruction of an undersampled signal is at the root of compressive sensing: when is an algorithm capable of reconstructing the signal? what quality is achievable? and how much time does reconstruction require? We have considered the worst-case performance of the smoothed ℓ0 norm reconstruction...... algorithm in a noiseless setup. Through an empirical tuning of its parameters, we have improved the phase transition (capabilities) of the algorithm for fixed quality and required time. In this paper, we present simulation results that show a phase transition surpassing that of the theoretical ℓ1 approach......: the proposed modified algorithm obtains 1-norm phase transition with greatly reduced required computation time....

K2-139 b: a low-mass warm Jupiter on a 29-d orbit transiting an active K0 V star

Science.gov (United States)

Barragán, O.; Gandolfi, D.; Smith, A. M. S.; Deeg, H. J.; Fridlund, M. C. V.; Persson, C. M.; Donati, P.; Endl, M.; Csizmadia, Sz; Grziwa, S.; Nespral, D.; Hatzes, A. P.; Cochran, W. D.; Fossati, L.; Brems, S. S.; Cabrera, J.; Cusano, F.; Eigmüller, Ph; Eiroa, C.; Erikson, A.; Guenther, E.; Korth, J.; Lorenzo-Oliveira, D.; Mancini, L.; Pätzold, M.; Prieto-Arranz, J.; Rauer, H.; Rebollido, I.; Saario, J.; Zakhozhay, O. V.

2018-04-01

We announce the discovery of K2-139 b (EPIC 218916923 b), a transiting warm-Jupiter (Teq = 547 ± 25 K) on a 29-d orbit around an active (log R^' _HK = -4.46 ± 0.06) K0 V star in K2 Campaign 7. We derive the system's parameters by combining the K2 photometry with ground-based follow-up observations. With a mass of 0.387 _{ - 0.075 } ^ {+ 0.083 }MJ and radius of 0.808 _{ - 0.033 } ^ {+ 0.034 }RJ, K2-139 b is one of the transiting warm Jupiters with the lowest mass known to date. The planetary mean density of 0.91 _{ - 0.20} ^ { + 0.24 } g cm-3can be explained with a core of ˜50 M⊕. Given the brightness of the host star (V = 11.653 mag), the relatively short transit duration (˜5 h), and the expected amplitude of the Rossiter-McLaughlin effect (˜25m s-1), K2-139 is an ideal target to measure the spin-orbit angle of a planetary system hosting a warm Jupiter.

Towards adaptation in e-learning 2.0

Science.gov (United States)

Cristea, Alexandra I.; Ghali, Fawaz

2011-04-01

This paper presents several essential steps from an overall study on shaping new ways of learning and teaching, by using the synergetic merger of three different fields: Web 2.0, e-learning and adaptation (in particular, personalisation to the learner). These novel teaching and learning ways-the latter focus of this paper-are reflected in and finally adding to various versions of the My Online Teacher 2.0 adaptive system. In particular, this paper focuses on a study of how to more effectively use and combine the recommendation of peers and content adaptation to enhance the learning outcome in e-learning systems based on Web 2.0. In order to better isolate and examine the effects of peer recommendation and adaptive content presentation, we designed experiments inspecting collaboration between individuals based on recommendation of peers who have greater knowledge, and compare this to adaptive content recommendation, as well as to "simple" learning in a system with a minimum of Web 2.0 support. Overall, the results of adding peer recommendation and adaptive content presentation were encouraging, and are further discussed in detail in this paper.

On the 1285,0 keV; 55-184WW state structure

International Nuclear Information System (INIS)

Kupryashkin, V.T.; Muzalev, P.N.; Feoktistov, A.I.

1977-01-01

The structure of the 184 W (1285.0 keV; 5 - ) states is discussed. Decay of this level is shown schematically. The data on multiplicities and probabilities of the γ-transitions for the levels 1285.0 keV; 5 - of 184 W and 1621.4 keV; 5 - of 182 W are presented. The transition amplitude parameters are plotted for different probabilities B(E3;5 - → I + ). The relation between the collective transition amplitudes is established. Transition amplitude parameters and their collective and two-particle components, as well as impurity amplitudes of collective excitation wave functions and matrix elements are given

Risk Management in Future Romanian E-Government 2.0 Projects

Directory of Open Access Journals (Sweden)

Didraga Otniel

2015-08-01

Full Text Available E-government public services in Romania must follow unitary procedures considering the new requirements of the European Union from the Digital Agenda for Europe Strategy 2020. E-government 2.0 has to be implemented because of the cultural and behavioral transformations in the interaction between governments and users of e-services. E-government 2.0 projects use tools and techniques of social media to accomplish their goals. This article examines the possible risk categories and the risk management procedures needed to mitigate risks in future Romanian e-government projects, according to the strategic lines of development for the Digital Agenda. We propose a risk management plan for the e-government lines of action within the strategic lines of development that includes identifying, assessing, and mitigating the risks. New and modernized government services through e-government 2.0 projects that apply risk management will bring a significant improvement in how citizens and businesses relate to government and will increase the use of e-government services.

Structural phase transition and multiferroic properties of Bi0.8A0.2Fe0.8Mn0.2O3 (A = Ca, Sr)

Science.gov (United States)

Rout, Jyoshna; Choudhary, R. N. P.

2018-05-01

The multiferroic BiFeO3 and Bi0.8A0.2Fe0.8Mn0.2O3 (A = Ca, Sr) have been synthesized using direct mechanosynthesis. Detailed investigations were made on the influence of Ca-Mn and Sr-Mn co-substitutions on the structure change, electric and magnetic properties of the BFO. Rietveld refinement on the XRD pattern of the modified samples clarifies the structural transition from R3c:H (parent BiFeO3) to the biphasic structure (R3c: H + Pnma). Scanning electron micrographs confirmed the polycrystalline nature of the materials and each of the microstructure comprised of uniformly distributed grains with less porosity. The dielectric measurements reveal that enhancement in dielectric properties due to the reduction of oxygen vacancies by substitutional ions. Studies of frequency-dependence of impedance and related parameters exhibit that the electrical properties of the materials are strongly dependent on temperature, and bear a good correlation with its microstructure. The bulk resistance (evaluated from impedance studies) is found to decrease with increasing temperature for all the samples. The alternating current (ac) conductivity spectra show a typical signature of an ionic conducting system, and are found to obey Jonscher's universal power law. Preliminary studies of magnetic characteristics of the samples reveal enhanced magnetization for Ca-Mn co-substituted sample. The magnetoelectric coefficient as the function of applied dc magnetizing field under fixed ac magnetic field 15.368 Oe is measured and this ME coefficient αME corresponds to induction of polarization by a magnetic field.

Small multiplicity events in e+ + e- → Z0 and unconventional phenomena

International Nuclear Information System (INIS)

Perl, M.L.

1986-12-01

Events with two-, four- or six-charged particles and no photons produced through the process e + + e - → Z 0 provide an opportunity to search for unconventional phenomena at the SLC and LEP electron-positron colliders. Examples of unconventional processes are compared with the expected background from electromagnetic processes and from charged lepton pair production

Direct CP violation in KL→π0e+e- beyond leading logarithms

International Nuclear Information System (INIS)

Buras, A.J.; Lautenbacher, Markus E.; Misiak, Mikolaj; Muenz, Manfred

1994-01-01

We analyze the direct CP violation in the rare decay K L →π 0 e + e - with QCD effects taken into account consistently in the next-to-leading order. We calculate the two-loop mixing between the four-quark ΔS=1 operators and the operator Q 7V =(sd) V-A (ee) V in the NDR and HV renormalization schemes. Using the known two-loop anomalous dimension matrix of the four-quark operators, we find that the coefficient C 7V (μ) depends only very weakly on μ, renormalization scheme and Λ MS . The next-to-leading QCD corrections enhance the direct CP violating contribution over its leading order estimate so that it remains dominant in spite of the recent decrease of vertical stroke V ub /V cb vertical stroke and vertical stroke V cb vertical stroke . We expect typically BR(K L →π 0 e + e - ) dir ∼6x10 -12 , although values as high as 10 -11 are not yet excluded. ((orig.))

A new upper limit for the branching ratio for the decay eta→π0e+e-

International Nuclear Information System (INIS)

Jan, M.R.; Grannis, P.; Jones, B.D.; Lipman, N.H.; Owen, D.P.; Peterson, V.Z.; Toner, W.T.

1975-01-01

A search has been made for the decay eta→π 0 e + e - in an optical spark chamber experiment at the Rutherford Laboratory. The observations are consistent with no events being seen and give an upper limit. Rate (eta→π 0 e + e - )/Rate (eta→ALL) -5 (90%C.L.). (author)

Polymorphic phase transition dependence of piezoelectric properties in (K0.5Na0.5)NbO3-(Bi0.5K0.5)TiO3 lead-free ceramics

International Nuclear Information System (INIS)

Du Hongliang; Zhou Wancheng; Luo Fa; Zhu Dongmei; Qu Shaobo; Li Ye; Pei Zhibin

2008-01-01

Lead-free ceramics (1 - x)(K 0.5 Na 0.5 )NbO 3 -x(Bi 0.5 K 0.5 )TiO 3 [(1 - x)KNN-xBKT] were synthesized by conventional solid-state sintering. The phase structure, microstructure and electrical properties of (1 - x)KNN-xBKT ceramics were investigated. At room temperature, the polymorphic phase transition (from the orthorhombic to the tetragonal phase) (PPT) was identified at x = 0.02 by the analysis of x-ray diffraction patterns and dielectric spectroscopy. Enhanced electrical properties (d 33 = 251 pC N -1 , k p = 0.49, k t = 0.50, ε 33 T / ε 0 =1260, tan δ = 0.03 and T C = 376 deg. C) were obtained in the ceramics with x = 0.02 owing to the formation of the PPT at 70 deg. C and the selection of an optimum poling temperature. The related mechanisms for high piezoelectric properties in (1 - x)KNN-xBKT (x = 0.02) ceramics were discussed. In addition, the results confirmed that the selection of the optimum poling temperature was an effective way to further improve the piezoelectric properties of KNN-based ceramics. The enhanced properties were comparable to those of hard Pb(Zr, Ti)O 3 ceramics and indicated that the (1 - x)KNN-xBKT (x = 0.02) ceramic was a promising lead-free piezoelectric candidate material for actuator and transducer applications

Phase transition and conduction mechanism in Pb{sub 2}Na{sub 0.8}R{sub 0.2}Nb{sub 4.8}Fe{sub 0.2}O{sub 15} material (R=rare earth)

Energy Technology Data Exchange (ETDEWEB)

Bouziane, M. [Laboratoire de Chimie du Solide Appliquée, Faculté des Sciences, Université Mohammed V-Agdal, Avenue Ibn Batouta, BP 1014 Rabat (Morocco); Taibi, M., E-mail: taibiens@yahoo.fr [Laboratoire de Physico-Chimie des Matériaux (LAF 502), Ecole Normale Supérieure, Université Mohammed V-Agdal, BP 5118 Rabat (Morocco); Boukhari, A. [Laboratoire de Chimie du Solide Appliquée, Faculté des Sciences, Université Mohammed V-Agdal, Avenue Ibn Batouta, BP 1014 Rabat (Morocco)

2013-11-15

Electrical properties of Pb{sub 2}Na{sub 0.8}Eu{sub 0.2}Nb{sub 4.8}Fe{sub 0.2}O{sub 15} tungsten bronze compound were investigated. Ferroelectric phase transition of diffuse type is observed at 395 °C. Conductivity study as a function of temperature (RT-600 °C) and at three different frequencies (10, 100 and 1000 kHz) suggests the existence of dominant ionic conduction. The rise of ac conductivity on increasing temperature supports the NTCR (negative temperature coefficient of resistance) behaviour of the material. The activation energies have been evaluated from ac conductivity using Arrhenius equation and discussed. Different conduction mechanisms were identified. For comparison, the conducting properties of Pb{sub 2}Na{sub 0.8}R{sub 0.2}Nb{sub 4.8}Fe{sub 0.2}O{sub 15} (R=Dy, Nd, La) were also investigated. - Graphical abstract: Thermal evolution of lnσ{sub ac} of Pb{sub 2}Na{sub 0.8}Eu{sub 0.2}Nb{sub 4.8}Fe{sub 0.2}O{sub 15} at selected frequencies. Display Omitted - Highlights: • We found that TB compounds exhibit a diffuse type of first- order transition. • A negative temperature coefficient of resistance (NTCR) behaviour is observed. • Three conduction mechanisms were identified: n-and/or p-type at low temperatures. • The conduction mechanism in the studied compounds is very complex.

Structural and electrical properties of La{sub 0.5}Ca{sub 0.5}Mn{sub 0.95}Fe{sub 0.05}O{sub 3+{delta}} perovskite

Energy Technology Data Exchange (ETDEWEB)

Mohamed, E.A., E-mail: emanattamohammed@yahoo.com [Department of Physics, Faculty of Science (Girl' s Branch), Al Azhar University, Nasr City, Cairo (Egypt)

2012-12-05

Highlights: Black-Right-Pointing-Pointer La{sub 0.5}Ca{sub 0.5}Mn{sub 0.95}Fe{sub 0.05}O{sub 3+{delta}} synthesis has been achieved by co-precipitation process. Black-Right-Pointing-Pointer Moessbauer results show an evidence for the local distortion of Mn(Fe)O{sub 6} octahedron. Black-Right-Pointing-Pointer Metal-Semiconductor transition temperature (T{sub p}) is observed. - Abstract: La{sub 0.5}Ca{sub 0.5}Mn{sub 0.95}Fe{sub 0.05}O{sub 3+{delta}} was synthesized by co-precipitation method. The structure refinement by using the Rietveld method indicates that the sample was single phase with the presence of small impurities (Mn{sub 3}O{sub 4}) and crystallizes in an orthorhombic (Pbmn) structure. The room temperature (RT) Moessbauer spectrum shows clear evidence of the local structural distortion of the Mn(Fe)O{sub 6} octahedron on the basis of non-zero nuclear quadrupole interactions for high-spin Fe{sup 3+} ions. The Jahn-Teller coupling strength (E{sub JT}) was estimated from the Moessbauer results. Metal-Semiconductor transition temperature (T{sub p}) is observed at 80 K. At high temperature (T{sub P} < T < {theta}{sub D}/2) conductivity data satisfy the variable range hopping (VRH) model. For T > {theta}{sub D}/2 the small polaron hopping model is more appropriate than the VRH model.

Vacancies in transition metals

International Nuclear Information System (INIS)

Allan, G.; Lannoo, M.

1976-01-01

A calculation of the formation energy and volume for a vacancy in transition metals is described. A tight-binding scheme is used for the d band and a Born-Mayer type potential to account for the repulsive part of the energy at small distances. The results show that the relaxation energy is small in all cases, less than 0.1 eV. This seems to be coherent with the good agreement obtained for the theoretical and experimental values of the formation energy Esub(F)sup(V) of the vacancy, without including relaxation. The center of the transitional series is found to give a contraction (Formation volume of order -0.4 at.vol.) whereas the edges are found to produce dilations. (author)

Quantum phase transitions

International Nuclear Information System (INIS)

Sachdev, S.

1999-01-01

Phase transitions are normally associated with changes of temperature but a new type of transition - caused by quantum fluctuations near absolute zero - is possible, and can tell us more about the properties of a wide range of systems in condensed-matter physics. Nature abounds with phase transitions. The boiling and freezing of water are everyday examples of phase transitions, as are more exotic processes such as superconductivity and superfluidity. The universe itself is thought to have passed through several phase transitions as the high-temperature plasma formed by the big bang cooled to form the world as we know it today. Phase transitions are traditionally classified as first or second order. In first-order transitions the two phases co-exist at the transition temperature - e.g. ice and water at 0 deg., or water and steam at 100 deg. In second-order transitions the two phases do not co-exist. In the last decade, attention has focused on phase transitions that are qualitatively different from the examples noted above: these are quantum phase transitions and they occur only at the absolute zero of temperature. The transition takes place at the ''quantum critical'' value of some other parameter such as pressure, composition or magnetic field strength. A quantum phase transition takes place when co-operative ordering of the system disappears, but this loss of order is driven solely by the quantum fluctuations demanded by Heisenberg's uncertainty principle. The physical properties of these quantum fluctuations are quite distinct from those of the thermal fluctuations responsible for traditional, finite-temperature phase transitions. In particular, the quantum system is described by a complex-valued wavefunction, and the dynamics of its phase near the quantum critical point requires novel theories that have no analogue in the traditional framework of phase transitions. In this article the author describes the history of quantum phase transitions. (UK)

Strategy approach for eLearning 2.0 deployment in Universities

Directory of Open Access Journals (Sweden)

Oskar Casquero

2010-12-01

Full Text Available The institutionally powered Personal Learning Environment (iPLE constitutes our vision of how Web 2.0 technologies, people arrangement and data sharing could be applied for delivering open, flexible, distributed and learner-centred learning environments to university members. Based on the iPLE, this paper explores a strategy approach that universities could follow in order to deploy eLearning 2.0 tools and services. With that aim in mind, we review the patterns that Web 2.0 has successfully applied, and have been proved to encourage people to interact and to share information. Then, we present an eLearning 2.0 provisioning strategy based on iPLEs. Finally, we explain how this strategy can help translating Web 2.0 patterns to learning, and positioning universities as eLearning 2.0 providers.

Angle Integrated Photoemission Study of SmO0.85F0.15FeAs

International Nuclear Information System (INIS)

Hong-Wei, Ou; Jia-Feng, Zhao; Yan, Zhang; Da-Wei, Shen; Bo, Zhou; Le-Xian, Yang; Cheng, He; Fei, Chen; Min, Xu; Yan, Chen; Dong-Lai, Feng; Tao, Wu; Xian-Hui, Chen

2008-01-01

The electronic structure of the new superconductor SmO 1-x F x FeAs (x = 0.15) is studied by angle-integrated photoemission spectroscopy. Our data show a sharp feature very close to the Fermi energy, and a relative flat distribution of the density of states between 0.5eV and 3eV binding energy, which agrees well with the band structure calculations considering an antiferromagnetic ground state. No noticeable gap opening is observed at 12K below the superconducting transition temperature, indicating the existence of large ungapped regions in the Brillouin zone. (condensed matter: electronic structure, electrical, magnetic, and optical properties)

Phase coexistence and high piezoelectric properties in (K0.40Na0.60)0.96Li0.04Nb0.80Ta0.20O3 ceramics

International Nuclear Information System (INIS)

Wu Ling; Zhang Jialiang; Shao Shoufu; Zheng Peng; Wang Chunlei

2008-01-01

Lead-free (K x Na 1-x ) 0.96 Li 0.04 Nb 0.80 Ta 0.20 O 3 ceramics with x = 0.10-0.70 were prepared by the conventional solid-state reaction technique. The influence of the K/Na ratio on the microstructure, crystallographic structure, phase transition and piezoelectric properties was investigated. It has been disclosed that the phase transition temperature T O-T drastically decreases with x in the narrow compositional range of x 0.30-0.40 and the phase coexistence of the orthorhombic structure and the tetragonal structure occurs near x = 0.40. The ceramics with x = 0.40 shows high piezoelectric properties (d 33 = 254 pC N -1 , k p = 51.5%, k t = 49.4% and k 33 = 66.6%, respectively) with low dielectric loss (tan δ 1.5%) and weak temperature dependence between 10 and 85 deg. C. In particular, the piezoelectric properties remain almost unchanged in the thermal ageing test from -125 to 300 deg. C. Therefore, this ceramic is considered to be a very promising lead-free piezoelectric material for practical applications. The relation of piezoelectric properties with morphotropic phase boundary and polymorphic phase transition was discussed

Magnetic and thermoelectric properties of electron doped Ca{sub 0.85}Pr{sub 0.15}MnO{sub 3}

Energy Technology Data Exchange (ETDEWEB)

Hossain Khan, Momin [Department of Physics, University of Kalyani, Kalyani 741235, West Bengal (India); Pal, Sudipta, E-mail: sudipta.pal@rediffmail.com [Department of Physics, University of Kalyani, Kalyani 741235, West Bengal (India); Bose, Esa [Department of Engineering Physics, B. P. P. I. M.T, Kolkata 700052, West Bengal (India)

2015-10-01

We have investigated temperature-dependent magnetization (M), magnetic susceptibility (χ) and thermoelectric (S) properties of the electron-doped Ca{sub 0.85}Pr{sub 0.15}MnO{sub 3}. With decrease of temperature, paramagnetic (PM) to antiferromagnetic (AFM) phase transition occurs with a well-defined Néel temperature (T{sub N}=122 K). Magnetic susceptibility measurements reveal that the paramagnetic state involves modified Curie–Weiss paramagnetism. Field cooled and zero field cooled magnetization measurements indicate a signature of magnetic frustration. Ferromagnetic (FM) double-exchange interactions associated with doped e{sub g} electrons are favored over competing AFM interactions below T{sub irr}=112 K. Magnetization data also shows a second-order phase transition. The sign reversal in S(T) has been interpreted in terms of the change in the electronic structure relating to the orbital degrees of freedom of the doped e{sub g} electron. Low temperature (5–140 K) thermoelectric power, S (T) signifies the importance of electron–magnon scattering process. - Highlights: • Magnetic and thermoelectric properties have been investigated in Ca{sub 0.85}Pr{sub 0.15}MnO{sub 3}. • It shows a PM–AFM second order phase transition at T{sub N}=122 K. • PM state involves modified Curie–Weiss paramagnetism. • The electron–magnon scattering dominates temperature dependent thermoelectric power.

Extended x-ray absorption fine structure study of phase transitions in the piezoelectric perovskite K0.5Na0.5NbO3

Science.gov (United States)

Kodre, A.; Tellier, J.; Arčon, I.; Malič, B.; Kosec, M.

2009-06-01

Following an x-ray diffraction study of phase transitions of the piezoelectric perovskite K0.5Na0.5NbO3 the structural changes of the material are studied using extended x-ray absorption fine structure analysis, whereby the neighborhood of Nb atom is determined in the temperature range of monoclinic, tetragonal, and cubic phases. Within the entire range Nb atom is displaced from the center of the octahedron of its immediate oxygen neighbors, as witnessed by the splitting of Nb-O distance. The model shows high prevalence of the displacement in the (111) crystallographic direction of the simple perovskite cell. The corresponding splitting of the Nb-Nb distance is negligible. There is no observable disalignment of the linear Nb-O-Nb bonds from the ideal cubic arrangement, judging from the intensity of the focusing of the photoelectron wave on the Nb-Nb scattering path by the interposed oxygen atom. As a general result, the phase transitions are found as an effect of the long-range order, while the placement of the atoms in the immediate vicinity remains largely unaffected.

Optical investigations of La0.7Ca0.3-xKxMnO3 (x = 0.00, 0.05 and 0.10 probed by spectroscopic ellipsometry

Directory of Open Access Journals (Sweden)

N. Sdiri

2012-07-01

Full Text Available Using spectroscopic ellipsometry, we have studied the optical properties of doped manganites at the paramagnetic state in polycrystalline La0.7Ca0.3-xKxMnO3 samples for (x = 0.00, 0.05 and 0.10 in the energy range of 3.2-5.5 eV at room temperature. The surface morphology of the samples was obtained by using atomic force microscopy (AFM. Refractive indices, extinction coefficients, the transmission ellipsometric parameters Ψ and Δ are investigated at different wavelengths. The study of the optical conductivity σ reveals that optical behaviour and the activated transport in the paramagnetic state of these materials are consistent with Jahn-Teller small polaron. In addition, the spectrum of the complex dielectric constant ε reveals peaks for all samples, the results may be explained by the presence of space charges from the strongly dipole-allowed O(2p−Mn(3d transition.

The effect of the excited leptons and the composite scalar bosons on the processes e+e-->W+W- or Z0Z0

International Nuclear Information System (INIS)

Tanimoto, Morimitsu

1985-01-01

We study the effects of the excited leptons and the composite scalar bosons on the processes e + e - ->W + W - or Z 0 Z 0 . The contribution of the excited leptons is sizably large compared with the prediction of the standard model in the LEP energy region if their masses lie below 300 GeV, but the contribution of the composite bosons is negligibly small. (orig.)

Attosecond sublevel beating and nonlinear dressing on the 3d-to-5p and 3p-to-5s core-transitions at 91.3 eV and 210.4 eV in krypton.

Science.gov (United States)

Seres, Enikoe; Seres, Jozsef; Namba, Shinichi; Afa, John; Serrat, Carles

2017-12-11

Applying extreme ultraviolet (XUV) transient absorption spectroscopy, the dynamics of the two laser dressed transitions 3d 5/2 -to-5p 3/2 and 3p 3/2 -to-5s 1/2 at photon energies of 91.3 eV and 210.4 eV were examined with attosecond temporal resolution. The dressing process was modeled with density matrix equations which are found to describe very accurately both the experimentally observed transmission dynamics and the linear and nonlinear dressing oscillations at 0.75 PHz and 1.5 PHz frequencies. Furthermore, using Fourier transform XUV spectroscopy, quantum beats from the 3d 5/2 -3d 3/2 and 3p 3/2 -3p 1/2 sublevels at 0.3 PHz and 2.0 PHz were experimentally identified and resolved.

A 0.2 V Micro-Electromechanical Switch Enabled by a Phase Transition.

Science.gov (United States)

Dong, Kaichen; Choe, Hwan Sung; Wang, Xi; Liu, Huili; Saha, Bivas; Ko, Changhyun; Deng, Yang; Tom, Kyle B; Lou, Shuai; Wang, Letian; Grigoropoulos, Costas P; You, Zheng; Yao, Jie; Wu, Junqiao

2018-04-01

Micro-electromechanical (MEM) switches, with advantages such as quasi-zero leakage current, emerge as attractive candidates for overcoming the physical limits of complementary metal-oxide semiconductor (CMOS) devices. To practically integrate MEM switches into CMOS circuits, two major challenges must be addressed: sub 1 V operating voltage to match the voltage levels in current circuit systems and being able to deliver at least millions of operating cycles. However, existing sub 1 V mechanical switches are mostly subject to significant body bias and/or limited lifetimes, thus failing to meet both limitations simultaneously. Here 0.2 V MEM switching devices with ≳10 6 safe operating cycles in ambient air are reported, which achieve the lowest operating voltage in mechanical switches without body bias reported to date. The ultralow operating voltage is mainly enabled by the abrupt phase transition of nanolayered vanadium dioxide (VO 2 ) slightly above room temperature. The phase-transition MEM switches open possibilities for sub 1 V hybrid integrated devices/circuits/systems, as well as ultralow power consumption sensors for Internet of Things applications. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Fractional-flux Little-Parks resistance oscillations in disordered superconducting Au0.7In0.3 cylinders

International Nuclear Information System (INIS)

Zadorozhny, Yu.; Liu, Y.

2001-01-01

The resistance of disordered superconducting Au 0.7 In 0.3 cylindrical films was measured as a function of applied magnetic field. In the high-temperature part of the superconducting transition regime, the resistance oscillated with a period of h/2e in units of the enclosed magnetic flux. However, at lower temperatures, the resistance peaks split. We argue that this splitting is due to the emergence of an oscillation with a period of h/4e, half of the flux quantum for paired electrons. The possible physical origin of the h/4e resistance oscillation is discussed in the context of new minima in the free energy of a disordered superconducting cylinder. (orig.)

Stable Ferroelectric Behavior of Nb-Modified Bi0.5K0.5TiO3-Bi(Mg0.5Ti0.5)O3 Lead-Free Relaxor Ferroelectric Ceramics

Science.gov (United States)

Zaman, Arif; Malik, Rizwan Ahmed; Maqbool, Adnan; Hussain, Ali; Ahmed, Tanveer; Song, Tae Kwon; Kim, Won-Jeong; Kim, Myong-Ho

2018-03-01

Crystal structure, dielectric, ferroelectric, piezoelectric, and electric field-induced strain properties of lead-free Nb-modified 0.96Bi0.5K0.5TiO3-0.04Bi(Mg0.5Ti0.5)O3 (BKT-BMT) piezoelectric ceramics were investigated. Crystal structure analysis showed a gradual phase transition from tetragonal to pseudocubic phase with increasing Nb content. The optimal piezoelectric property of small-signal d 33 was enhanced up to ˜ 68 pC/N with a lower coercive field ( E c) of ˜ 22 kV/cm and an improved remnant polarization ( P r) of ˜ 13 μC/cm2 for x = 0.020. A relaxor-like behavior with a frequency-dependent Curie temperature T m was observed, and a high T m around 320°C was obtained in the investigated system. This study suggests that the ferroelectric properties of BKT-BMT was significantly improved by means of Nb substitution. The possible shift of depolarization temperature T d toward high temperature T m may have triggered the spontaneous relaxor to ferroelectric phase transition with long-range ferroelectric order without any traces of a nonergodic relaxor state in contradiction with Bi0.5Na0.5TiO3-based systems. The possible enhancement in ferroelectric and piezoelectric properties near the critical composition x = 0.020 may be attributed to the increased anharmonicity of lattice vibrations which may facilitate the observed phase transition from a low-symmetry tetragonal to a high-symmetry cubic phase with a decrease in the lattice anisotropy of an undoped sample. This highly flexible (at a unit cell level) narrow compositional range triggers the enhancement of d 33 and P r values.

Photo-Induced Phase Transitions to Liquid Crystal Phases: Influence of the Chain Length from C8E4 to C14E4

Directory of Open Access Journals (Sweden)

Simone Techert

2009-09-01

Full Text Available Photo-induced phase transitions are characterized by the transformation from phase A to phase B through the absorption of photons. We have investigated the mechanism of the photo-induced phase transitions of four different ternary systems CiE4/alkane (i with n = 8, 10, 12, 14; cyclohexane/H2O. We were interested in understanding the effect of chain length increase on the dynamics of transformation from the microemulsion phase to the liquid crystal phase. Applying light pump (pulse/x-ray probe (pulse techniques, we could demonstrate that entropy and diffusion control are the driving forces for the kind of phase transition investigated.

Tuning of cu doping on phase transition and high-field phase diagram of Nd{sub 0.5}Sr{sub 0.5}Mn{sub 1−x}Cu{sub x}O{sub 3}

Energy Technology Data Exchange (ETDEWEB)

Shang, C. [Wuhan National High Magnetic Field Center, Huazhong University of Science and Technology, Wuhan 430074 (China); School of Physics, Huazhong University of Science and Technology, Wuhan 430074 (China); Xia, Z.C., E-mail: xia9020@hust.edu.cn [Wuhan National High Magnetic Field Center, Huazhong University of Science and Technology, Wuhan 430074 (China); Wei, M.; Jin, Z.; Chen, B.R.; Shi, L.R. [Wuhan National High Magnetic Field Center, Huazhong University of Science and Technology, Wuhan 430074 (China); School of Physics, Huazhong University of Science and Technology, Wuhan 430074 (China); Ouyang, Z.W. [Wuhan National High Magnetic Field Center, Huazhong University of Science and Technology, Wuhan 430074 (China); Huang, S.; Xiao, G.L. [Wuhan National High Magnetic Field Center, Huazhong University of Science and Technology, Wuhan 430074 (China); School of Physics, Huazhong University of Science and Technology, Wuhan 430074 (China)

2016-10-15

Pulsed high magnetic fields up to 52 T have been used in the systematic investigation of the magnetic properties of manganites Nd{sub 0.5}Sr{sub 0.5}Mn{sub 1−x}Cu{sub x}O{sub 3} (0≤x≤0.15). The Cu-doping dependent first-order metamagnetic transitions are observed below the charge ordering temperature, which is ascribed to both Cu-doping and field-induced collapse of the charge ordering with antiferromagnetic phase. Based on the magnetization and electrical transport measurements, a three-dimensional phase diagram with coordinate axis of temperature, magnetic field, and doping level has been obtained, in which the critical fields of the metamagnetic transitions increase with the increase in Cu content and decrease with increasing temperature. The experimental results confirm that Mn-site substitution with Cu destroys the Mn{sup 3+}–O{sup 2−}–Mn{sup 4+} bridges and weakens the double exchange interaction between Mn{sup 3+} and Mn{sup 4+} ions, which shows an obvious tuning effect on the metamagnetic transition under the external magnetic field. - Highlights: • Tuning effect of Cu-doping on the properties of Nd{sub 0.5}Sr{sub 0.5}Mn{sub 1−x}Cu{sub x}O{sub 3} was studied. • First-order metamagnetic transition was observed under high magnetic fields. • A phase diagram with temperature, magnetic field and doping level was obtained. • Cu-doping weakens the ferromagnetic coupling in Nd{sub 0.5}Sr{sub 0.5}Mn{sub 1−x}Cu{sub x}O{sub 3}.

The one-particle scenario for the metal-insulator transition in two-dimensional systems at T = 0

CERN Document Server

Tarasov, Y V

2003-01-01

The conductance of bounded disordered electron systems is calculated by reducing the original dynamic problem of arbitrary dimensionality to a set of strictly one-dimensional problems for one-particle mode propagators. The metallic ground state of a two-dimensional conductor, which is considered as a limiting case of three-dimensional quantum waveguide, is shown to result from its multi-modeness. As the waveguide thickness is reduced, e.g., by applying a 'pressing' potential, the electron system undergoes a set of continuous phase transitions related to discrete variations of the number of extended modes. The closing of the last current carrying mode is regarded as a phase transition of the electron system from metallic to dielectric state. The obtained results agree qualitatively with the observed 'anomalies' of resistivity of different two-dimensional electron and hole systems.

Calibration of the ALICE transition radiation detector and a study of Z0 and heavy quark production in pp collisions at the LHC

International Nuclear Information System (INIS)

Bailhache, Raphaelle

2009-01-01

The ALICE Experiment is one of the four experiments installed at the Large Hadron Collider (LHC). One of its detector-systems, the Transition Radiation Detector (TRD), is a gas detector designed for electron identification and charged particle tracking. The charged particle ionizes the gas along its path and electrons drift in an uniform field of 700 V/cm over 3 cm before being amplified. We implemented procedures to calibrate the drift velocity of the electrons, the time-offset of the signal, the amplification factor and the width of the Pad Response Function (PDF) characterizing the sharing of the deposited charge over adjacent pads. Physics events (pp and PbPb collisions) will be used. The performances of the algorithms were tested on simulated pp collisions at √(s)=14 TeV and on first real data taken with cosmic-rays in the ALICE setup. The calibration software was installed on the Data Acquisition System at CERN and executed continuously during the cosmic-ray data taking in 2008, providing a first determination of the calibration constants. This thesis presents also a study on the capability of the ALICE central barrel to detect the Z 0 boson through the decay Z 0 →e + e - in pp collisions at 14 TeV. We demonstrated that the Z 0 →e + e - is characterized by a very clean signal in the dielectron reconstructed invariant mass spectrum. At such high transverse momentum (about 45 GeV/c), the electrons from Z 0 are identified with the Transition Radiation Detector. The remaining background from misidentified pions and electrons from heavy-flavored decays are rejected by the requirement of two isolated reconstructed tracks. The main challenge comes from the very small production rate. Therefore we estimated the efficiency of a trigger based on a low p T cut and electron identification with the TRD and showed that about 100 Z 0 →e + e - can be reconstructed per year employing such a trigger. Another physics topics investigated in this thesis is the measurement

Diffractive production of two ρ0L mesons in e+e- collisions

International Nuclear Information System (INIS)

Segond, M.; Wallon, S.; Szymanowski, L.

2007-01-01

We present an estimate of the cross-section for the exclusive production of a ρ L 0 -meson pair in e + e - scattering, which will be studied in the future high-energy International Linear Collider. For this aim, we complete calculations of the Born order approximation of the amplitudes γ * L,T (Q 1 2 )γ * L,T (Q 2 2 )→ρ L 0 ρ L 0 , for arbitrary polarization of virtual photons and longitudinally polarized mesons, in the kinematical region s>>-t,Q 1 2 ,Q 2 2 . These processes are completely calculable in the hard region Q 1 2 ,Q 2 2 >>Λ 2 QCD , and we perform most of the calculations in an analytical way. The resulting cross-section turns out to be large enough for this process to be measurable with foreseen luminosity and energy, for Q 1 2 and Q 2 2 in the range of a few GeV 2 . (orig.)

Energy spectra and E2 transition rates of 124—130Ba

Science.gov (United States)

Sabri, H.; Seidi, M.

2016-10-01

In this paper, we have studied the energy spectra and B(E2) values of 124—130Ba isotopes in the shape phase transition region between the spherical and gamma unstable deformed shapes. We have used a transitional interacting Boson model (IBM), Hamiltonian which is based on affine SU(1,1) Lie algebra in the both IBM-1 and 2 versions and also the Catastrophe theory in combination with a coherent state formalism to generate energy surfaces and determine the exact values of control parameters. Our results for control parameters suggest a combination of U(5) and SO(6) dynamical symmetries in this isotopic chain. Also, the theoretical predictions can be rather well reproduce the experimental counterparts, when the control parameter is approached to the SO(6) limit.

Dispersive analysis of the pion transition form factor

Energy Technology Data Exchange (ETDEWEB)

Hoferichter, M. [Technische Universitaet Darmstadt, Institut fuer Kernphysik, Darmstadt (Germany); GSI Helmholtzzentrum fuer Schwerionenforschung GmbH, ExtreMe Matter Institute EMMI, Darmstadt (Germany); University of Bern, Albert Einstein Center for Fundamental Physics, Institute for Theoretical Physics, Bern (Switzerland); Kubis, B.; Niecknig, F.; Schneider, S.P. [Universitaet Bonn, Helmholtz-Institut fuer Strahlen- und Kernphysik (Theorie) and Bethe Center for Theoretical Physics, Bonn (Germany); Leupold, S. [Uppsala Universitet, Institutionen foer fysik och astronomi, Box 516, Uppsala (Sweden)

2014-11-15

We analyze the pion transition form factor using dispersion theory. We calculate the singly-virtual form factor in the time-like region based on data for the e{sup +}e{sup -} → 3π cross section, generalizing previous studies on ω, φ → 3π decays and γπ → ππ scattering, and verify our result by comparing to e{sup +}e{sup -} → π{sup 0}γ data. We perform the analytic continuation to the space-like region, predicting the poorlyconstrained space-like transition form factor below 1 GeV, and extract the slope of the form factor at vanishing momentum transfer a{sub π} = (30.7 ± 0.6) x 10{sup -3}. We derive the dispersive formalism necessary for the extension of these results to the doubly-virtual case, as required for the pion-pole contribution to hadronic light-by-light scattering in the anomalous magnetic moment of the muon. (orig.)

Emerging 0D Transition-Metal Dichalcogenides for Sensors, Biomedicine, and Clean Energy.

Science.gov (United States)

Li, Bang Lin; Setyawati, Magdiel Inggrid; Zou, Hao Lin; Dong, Jiang Xue; Luo, Hong Qun; Li, Nian Bing; Leong, David Tai

2017-08-01

Following research on two-dimensional (2D) transition metal dichalcogenides (TMDs), zero-dimensional (0D) TMDs nanostructures have also garnered some attention due to their unique properties; exploitable for new applications. The 0D TMDs nanostructures stand distinct from their larger 2D TMDs cousins in terms of their general structure and properties. 0D TMDs possess higher bandgaps, ultra-small sizes, high surface-to-volume ratios with more active edge sites per unit mass. So far, reported 0D TMDs can be mainly classified as quantum dots, nanodots, nanoparticles, and small nanoflakes. All exhibited diverse applications in various fields due to their unique and excellent properties. Of significance, through exploiting inherent characteristics of 0D TMDs materials, enhanced catalytic, biomedical, and photoluminescence applications can be realized through this exciting sub-class of TMDs. Herein, we comprehensively review the properties and synthesis methods of 0D TMDs nanostructures and focus on their potential applications in sensor, biomedicine, and energy fields. This article aims to educate potential adopters of these excitingly new nanomaterials as well as to inspire and promote the development of more impactful applications. Especially in this rapidly evolving field, this review may be a good resource of critical insights and in-depth comparisons between the 0D and 2D TMDs. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

A Structural Study of the Pseudo-Binary Mercury Chalcogenide Alloy HgSe_{0.7}S_{0.3} at High Pressure

CERN Document Server

Kozlenko, D P; Ehm, L; Knorr, K; Hull, S; Shchennikov, V V; Voronin, V I

2002-01-01

The structure of the pseudo-binary mercury chalcogenide alloy HgSe_{0.7}S_{0.3} has been studied by means of X-ray and neutron powder diffraction at pressure up to 8.5 GPa. A phase transition from the cubic zinc blende structure to the hexagonal cinnabar structure was observed at P{\\sim}1 GPa. The obtained structural parameters were used for the analysis of the geometrical relationship between the zinc blende and the cinnabar phases. The zinc blende-cinnabar phase transition is discussed in the framework of Landau theory of the phase transitions. It was found that the possible order parameter for the structural transformation is the spontaneous strain e_{4}. This assignment agrees with previously observed high pressure behaviour of the elastic constants of other mercury chalcogenides.

A structural study of the pseudo-binary mercury chalcogenide alloy HgSe0.7S0.3 at high pressure

International Nuclear Information System (INIS)

Kozlenko, D.P.; Savenko, B.N.; Ehm, L.; Knorr, K.; Hull, S.; Shchennikov, V.V.; Voronin, V.I.

2002-01-01

The structure of the pseudo-binary mercury chalcogenide alloy HgSe 0.7 S 0.3 has been studied by means of X-ray and neutron powder diffraction at pressure up to 8.5 GPa. A phase transition from the cubic zinc blende structure to the hexagonal cinnabar structure was observed at P∼1 GPa. The obtained structural parameters were used for the analysis of the geometrical relationship between the zinc blende and the cinnabar phases. The zinc blende-cinnabar phase transition is discussed in the framework of the Landau theory of phase transitions. It was found that the possible order parameter for the structural transformation is the spontaneous strain e 4 . This assignment agrees with previously observed high pressure behaviour of the elastic constants of other mercury chalcogenides

Expressions for neutrino wave functions and transition probabilities at three-neutrino oscillations in vacuum and some of their applications

International Nuclear Information System (INIS)

Beshtoev, Kh.M.

2006-01-01

I have considered three-neutrino vacuum transitions and oscillations in the general case and obtained expressions for neutrino wave functions in three cases: with CP violation, without CP violation and in the case when direct ν e - ν τ transitions are absent β(θ 13 ) = 0 (some works indicate this possibility). Then using the existing experimental data some analysis has been fulfilled. This analysis definitely has shown that direct transitions ν e - ν τ cannot be closed for the Solar neutrinos, i. e., β(θ 13 ) ≠ 0. It is also shown that the possibility that β(θ 13 ) = 0 cannot be realized by using the mechanism of resonance enhancement of neutrino oscillations in matter (the Sun). It was found out that the probability of ν e - ν e neutrino transitions is a positive defined value, if in reality neutrino oscillations take place, only if the angle of ν e , ν τ mixing β ≤ 15 - 17 deg

Lipid mobilization, immune function and the paradigm of vitamin E in transition cows.

Directory of Open Access Journals (Sweden)

Ioannis Politis

2016-06-01

Full Text Available The number of metabolic disorders that dairy cows have to cope during the transition to lactation can be divided in three main categories. The first category includes disorders related to abnormal energy metabolism (ketosis, fatty liver, acidosis. The second and the third categories include disorders related to mineral metabolism (milk fever and disorders related directly or indirectly to impaired immune function (mastitis, metritis, retained placenta, respectively. Among the many physiological changes during the transition period, perhaps the most crucial, is an increase in the concentration of plasma non-esterified fatty acids (NEFA. A portion of this increase in NEFA is obligatory and it is under hormonal control while another portion is the result of a situation known as negative energy balance (difference between energy consumed and energy spent. In this presentation I will present data from a collaborative study between the University of Milan and the Agricultural University of Athens which proves that negative correlations exist between blood concentrations of NEFA and β-hydroxybutyrate with α-tocopherol. The adipose tissue contains two main categories of cells: adipocytes and immunocompetent cells mainly monocytes/macrophages. Our research has tested the hypothesis that a cross-talk exists between adipocytes and monocytes/macrophages and this cross-talk is mediated by fatty acids released by adipocytes especially during the transition period. Results indicate that all fatty acids tested (myristic, palmitic, palmitoleic, stearic and oleic upregulate the expression of numerous pro-inflammatory genes by both monocytes but neutrophils, as well. The longer the carbon chain, the most potent is the effect.  Another hypothesis that we have tested is that vitamin E can interfere and block the cross talk between adipocytes and immunocompetent cells. Against this notion, α-tocopherol does not interfere with the effect of fatty acids on

Magnetocaloric materials and first order phase transitions

DEFF Research Database (Denmark)

Neves Bez, Henrique

and magnetocaloric regenerative tests. The magnetic, thermal and structural properties obtained from such measurements are then evaluated through different models, i.e. the Curie-Weiss law, the Bean-Rodbell model, the free electron model and the Debye model.The measured magnetocaloric properties of La0.67Ca0.33MnO3...... heat capacity, magnetization and entropy change measurements. By measuring bulky particles (with a particle size in the range of 5001000 μm) of La(Fe,Mn,Si)13Hz with first order phase transition, it was possible to observe very sharp transitions. This is not the case for finer ground particles which......This thesis studies the first order phase transitions of the magnetocaloric materials La0.67Ca0.33MnO3 and La(Fe,Mn,Si)13Hz trying to overcome challenges that these materials face when applied in active magnetic regenerators. The study is done through experimental characterization and modelling...

On the d{sub 5/2}<->g{sub 7/2} Transitions in Odd Mass Pm Nuclei

Energy Technology Data Exchange (ETDEWEB)

Baecklin, A; Malmskog, S G

1967-05-15

The half-lives of the first excited levels in {sup 145}Pm and {sup 147}Pm have been measured by the delayed coincidence method and are 2.69 {+-} 0.08 nsec and 2.51 {+-} 0.05 nsec, respectively. From a measurement of the L subshell ratios of the 61 keV transition in {sup 145}Pm, an E2 admixture of 0.15 {+-} 0.05 per cent has been obtained. The transition energy was found to be 61.25 {+-} 0.05 keV. The experimental reduced E2 transition probabilities from the first excited states to the ground states of {sup 145}Pm, {sup 147}Pm and {sup 149}Pm have been compared to the theoretical predictions by Sorensen.

Differential electron scattering cross sections for the 3 (2)S to 3 (2)P0 h, k transitions in Mg II - Comparison of experiment and theory

Science.gov (United States)

Williams, I. D.; Chutjian, A.; Msezane, A. Z.; Henry, R. J. W.

1985-01-01

Angular differential electron scattering cross sections are reported for the unresolved inelastic 3s (2)S to 3p (2)P0 h, k transitions in Mg II for the first time. Relative differential cross sections have been measured at 35 eV and 50 eV in the angular range of Theta between 6 and 17 deg using the newly developed electron energy loss technique in a crossed electron-ion beam geometry. Theoretical values have been calculated in a five-state close-coupling approximation in which 3s, 3p, 3d, 4s, and 4p states were included, and to which measurements were normalized at Theta = 12 deg.

Electron tunneling studies of ultrathin films near the superconductor-to-insulator transition

International Nuclear Information System (INIS)

Valles, J.M. Jr.; Garno, J.P.

1994-01-01

Electron tunneling measurements on ultrathin quench-condensed films near the superconductor-to-insulator (SI) transition reveal that the superconducting state degrades with increasing normal state sheet resistance, R □ , in a manner that depends strongly on film morphology. In homogeneously disordered films, the superconducting energy gap Δ 0 decreases continuously and appears to go to zero at the SI transition. In granular films the transport properties degrade while Δ 0 remains constant. Measurements in the normal state reveal disorder enhanced e - -e - interaction corrections to the density of states. These effects are strong and depend on morphology in a manner that is consistent with their playing an important role in driving the SI transition. (orig.)

Complexes due to donor-acceptor-type transitions in GaAs

International Nuclear Information System (INIS)

Reynolds, D.C.; Litton, C.W.; Almassy, R.J.; McCoy, G.L.; Nam, S.B.

1980-01-01

A sharp line transition at 1.51385 eV has been observed in the photoluminescence spectra of an epitaxially grown crystal of GaAs. A Si 3 N 4 cap was applied by plasma deposition and the crystal was then annealed at 850 0 C for 15 min. The sharp emission line was observed after annealing. This transition was analyzed in perturbing magnetic and strain fields and is shown to result from a donor-acceptor-type complex. Three additional sharp line transitions are reported and the behavior of all of these transitions is compared with the behavior of similar transitions reported in the literature. Models for the complexes involved are re-examined and components of the complexes are suggested. All of the sharp line transitions were introduced in the growing process with the exception of the 1.51385-eV line which was introduced in the capping and annealing process

Micro-Raman study of the microheterogeneity in the MA-MC phase transition in 0.67PbMg1/3Nb2/3O3-0.33PbTiO3 single crystal

KAUST Repository

Yang, Y.

2011-04-20

Polarized Raman spectroscopy has been employed to investigate the evolution of the microstructure of 0.67PbMg1/3Nb2/3O3-0.33PbTiO3 (PMN-33%PT) single crystal in the temperature range from −195 to 300 °C. The M A-M C-cubic transition sequence was observed in the microareas with M A-type (space group Cm) and M C-type (space group Pm) monoclinic structures. Interestingly, the M A-M Cphase transition temperature exhibited remarkable microareal dependence due to the spatial inhomogeneity of polar nanoregions (PNRs). The M C-cubic phase transition took place at 155 °C in both microareas, which consisted well with previous reports. These results reveal that the phase transition in PMN-33%PT single crystal is closely related with the thermal dynamics of PNRs, which will be useful for understanding the microheterogeneity in this compound.

First measurement of the reaction π-e->π-π0e

International Nuclear Information System (INIS)

Amendolia, S.R.; Badelek, B.; Batignani, G.; Bertolucci, E.; Bosisio, L.; Bradaschia, C.; Fidecaro, F.; Foa, L.; Focardi, E.; Giorgi, M.A.; Marrocchesi, P.S.; Menzione, A.; Raso, G.; Ristori, L.; Scribano, A.; Tonelli, G.; Triggiani, G.; Arik, M.; Bellamy, E.H.; Green, M.G.; Heath, G.P.; Landon, M.P.J.; March, P.V.; Saltmarsh, C.G.; Saoucha, A.; Strong, J.A.; Tenchini, R.; Von Schlippe, W.; Van Herwijnen, E.; Budinich, M.; Liello, F.; Milotti, E.; Ragusa, F.; Rolandi, L.; Stefanini, A.; Fabbri, F.L.; Laurelli, P.; Spillantini, P.; Zallo, A.; Frank, S.G.F.; Harvey, J.; Storey, D.

1985-01-01

The first observation of neutral pion production in πe inelastic scattering is presented. The cross section at 300 GeV for vertical stroketvertical stroke > 10 -3 (GeV/c) 2 is 2.11 +- 0.47 nb, in good agreement with the theory of PCAC anomalies with 3 quark colours. (orig.)

Polarizabilities of the beryllium clock transition

International Nuclear Information System (INIS)

Mitroy, J.

2010-01-01

The polarizabilities of the three lowest states of the beryllium atom are determined from a large basis configuration interaction calculation. The polarizabilities of the 2s 2 1 S e ground state (37.73a 0 3 ) and the 2s2p 3 P 0 o metastable state (39.04a 0 3 ) are found to be very similar in size and magnitude. This leads to an anomalously small blackbody radiation shift at 300 K of -0.018(4) Hz for the 2s 2 1 S e -2s2p 3 P 0 o clock transition. Magic wavelengths for simultaneous trapping of the ground and metastable states are also computed.

Order-disorder transition of vortex matter in Mg0.95B2

International Nuclear Information System (INIS)

Oliveira, A.A.M.; Sharma, P.A.; Hur, N.; Cheong, S-W.; Ortiz, W.A.

2008-01-01

Third-harmonic susceptibility has been employed to probe the order-disorder transition of vortex matter of a good-quality sample of MgB 2 with random disorder. In the major part of the temperature interval, the measured boundary line can be adjusted by a power-law function, in accordance with theoretical models for the melting of the ordered phase of a 3D vortex-glass. For larger temperatures, however, thermally-induced depinning anticipates disorder, which is also predictable for the vortex matter behavior of a clean system with small amounts of randomly distributed disorder, as is the case of the Mg 0.95 B 2 sample studied here

Study of electron transition energies between anions and cations in spinel ferrites using differential UV–vis absorption spectra

International Nuclear Information System (INIS)

Xue, L.C.; Wu, L.Q.; Li, S.Q.; Li, Z.Z.; Tang, G.D.; Qi, W.H.; Ge, X.S.; Ding, L.L.

2016-01-01

It is very important to determine electron transition energies (E_t_r) between anions and different cations in order to understand the electrical transport and magnetic properties of a material. Many authors have analyzed UV–vis absorption spectra using the curve (αhν)"2 vs E, where α is the absorption coefficient and E(=hν) is the photon energy. Such an approach can give only two band gap energies for spinel ferrites. In this paper, using differential UV–vis absorption spectra, dα/dE vs E, we have obtained electron transition energies (E_t_r) between the anions and cations, Fe"2"+ and Fe"3"+ at the (A) and [B] sites and Ni"2"+ at the [B] sites for the (A)[B]_2O_4 spinel ferrite samples Co_xNi_0_._7_−_xFe_2_._3O_4 (0.0≤x≤0.3), Cr_xNi_0_._7Fe_2_._3_−_xO_4 (0.0≤x≤0.3) and Fe_3O_4. We suggest that the differential UV–vis absorption spectra should be accepted as a general analysis method for determining electron transition energies between anions and cations.

Cross Sections for the Reactions e+e to K+ K- pi+pi-, K+ K- pi0pi0, and K+ K- K+ K- Measured Using Initial-State Radiation

Energy Technology Data Exchange (ETDEWEB)

Lees, J.P.; Poireau, V.; Prencipe, E.; Tisserand, V.; /Annecy, LAPP; Garra Tico, J.; Grauges, E.; /Barcelona U., ECM; Martinelli, M.; /INFN, Trieste /Trieste U.; Milanes, D.A.; /INFN, Trieste /Trieste U.; Palano, A.; /INFN, Trieste /Trieste U.; Pappagallo, M.; /INFN, Trieste /Trieste U. /INFN, Bari /Bari U. /Bari U. /INFN, Bari; Eigen, G.; Stugu, B.; Sun, L.; /Bergen U.; Brown, D.N.; Kerth, L.T.; Kolomensky, Yu.G.; Lynch, G.; Osipenkov, I.L.; /LBL, Berkeley /UC, Berkeley; Koch, H.; Schroeder, T.; /Ruhr U., Bochum; Asgeirsson, D.J.; /British Columbia U. /Brunel U. /Novosibirsk, IYF /UC, Irvine /UC, Riverside /UC, Santa Barbara /UC, Santa Cruz /Caltech /Cincinnati U. /Colorado U. /Colorado State U. /Dortmund U. /Dresden, Tech. U. /Ecole Polytechnique /Edinburgh U. /INFN, Trieste /INFN, Trieste /INFN, Trieste /Trieste U. /INFN, Trieste /Trieste U. /INFN, Trieste /Trieste U. /INFN, Trieste /Trieste U. /INFN, Trieste /Trieste U. /INFN, Trieste /Trieste U. /INFN, Trieste /Trieste U. /INFN, Trieste /INFN, Ferrara /Ferrara U. /Frascati /INFN, Trieste /Trieste U. /INFN, Trieste /Trieste U. /INFN, Trieste /Trieste U. /INFN, Trieste /Trieste U. /INFN, Trieste /INFN, Trieste /Trieste U. /INFN, Trieste /INFN, Genoa /Genoa U. /Indian Inst. Tech., Guwahati /Harvard U. /Harvey Mudd Coll. /Heidelberg U. /Humboldt U., Berlin /Imperial Coll., London /Iowa State U. /Iowa State U. /Johns Hopkins U. /Orsay, LAL /LLNL, Livermore /Liverpool U. /Queen Mary, U. of London /Royal Holloway, U. of London /Louisville U. /Mainz U., Inst. Kernphys. /Manchester U., Comp. Sci. Dept. /Maryland U. /Massachusetts U., Amherst /MIT /McGill U. /INFN, Trieste /Trieste U. /INFN, Trieste /Trieste U. /INFN, Trieste /INFN, Trieste /Trieste U. /INFN, Trieste /Trieste U. /INFN, Milan /Milan U. /Mississippi U. /Montreal U. /INFN, Trieste /Trieste U. /INFN, Trieste /Trieste U. /INFN, Trieste /Trieste U. /INFN, Trieste /Trieste U. /INFN, Naples /Naples U. /NIKHEF, Amsterdam /Notre Dame U. /Ohio State U. /Oregon U. /INFN, Trieste /Trieste U. /INFN, Trieste /Trieste U. /INFN, Trieste /Trieste U. /INFN, Trieste /Trieste U. /INFN, Trieste /INFN, Trieste /INFN, Trieste /INFN, Trieste /Trieste U. /INFN, Trieste /Trieste U. /INFN, Padua /Padua U. /Paris U., VI-VII /INFN, Trieste /Trieste U. /INFN, Trieste /Trieste U. /INFN, Trieste /Trieste U. /INFN, Perugia /Perugia U. /INFN, Trieste /Trieste U. /INFN, Trieste /Trieste U. /INFN, Trieste /Trieste U. /INFN, Trieste /Trieste U. /INFN, Trieste /Trieste U. /INFN, Trieste /Trieste U. /INFN, Trieste /Trieste U. /INFN, Trieste /Trieste U. /INFN, Trieste /Trieste U. /INFN, Trieste /Trieste U. /INFN, Trieste /INFN, Pisa /Princeton U. /INFN, Trieste /INFN, Trieste /INFN, Trieste /Trieste U. /INFN, Trieste /INFN, Trieste /Trieste U. /INFN, Trieste /Trieste U. /INFN, Trieste /INFN, Trieste /INFN, Trieste /INFN, Rome /Rome U. /Rostock U. /Rutherford /DAPNIA, Saclay /SLAC /South Carolina U. /Southern Methodist U. /Stanford U., Phys. Dept. /SUNY, Albany /Tel Aviv U. /Tennessee U. /Texas U. /Texas U., Dallas /INFN, Trieste /Trieste U. /INFN, Trieste /Trieste U. /INFN, Trieste /Trieste U. /INFN, Turin /Turin U. /INFN, Trieste /Trieste U. /INFN, Trieste /Trieste U. /INFN, Trieste /Trieste U. /Valencia U., IFIC /Victoria U. /Warwick U. /Wisconsin U., Madison

2011-08-19

We study the processes e{sup +}e{sup -} {yields} K{sup +}K{sup -}{pi}{sup +}{pi}-{gamma}, K{sup +}K{sup -}{pi}{sup 0}{pi}{sup 0}{gamma}, and K{sup +}K{sup -}K{sup +}K{sup -}{gamma}, where the photon is radiated from the initial state. About 84000, 8000, and 4200 fully reconstructed events, respectively, are selected from 454 fb{sup -1} of BABAR data. The invariant mass of the hadronic final state defines the e{sup +}e{sup -} center-of-mass energy, so that the K{sup +}K{sup -}{pi}{sup +}{pi}{sup -}{gamma} data can be compared with direct measurements of the e{sup +}e{sup -} {yields} K{sup +}K{sup -}{pi}{sup +}{pi}{sup -} reaction. No direct measurements exist for the e{sup +}e{sup -} {yields} K{sup +}K{sup -}{pi}{sup 0}{pi}{sup 0} or e{sup +}e{sup -} {yields} K{sup +}K{sup -}K{sup +}K{sup -} reactions, and we present an update of our previous result with doubled statistics. Studying the structure of these events, we find contributions from a number of intermediate states, and extract their cross sections. In particular, we perform a more detailed study of the e{sup +}e{sup -} {yields} {phi}(1020){pi}{pi}{gamma} reaction, and confirm the presence of the Y (2175) resonance in the {phi}(1020)f{sub 0}(980) and K{sup +}K{sup -} f{sub 0}(980) modes. In the charmonium region, we observe the J/{psi} in all three final states and in several intermediate states, as well as the {phi}(2S) in some modes, and measure the corresponding branching fractions.

Interpretation of specific-heat and spontaneous-magnetization anomalies at the reentrant superconducting - ferromagnetic transition in (Ho0.6Er0.4)Rh4B4

International Nuclear Information System (INIS)

Woolf, L.D.; Johnston, D.C.; Mook, H.A.; Koehler, W.C.; Maple, M.B.; Fisk, Z.

1981-09-01

Analysis of neutron-diffraction data on the compound (Ho 0 . 6 Er 0 . 4 )Rh 4 B 4 indicates that the Curie temperature is depressed by about 0.2 K due to the occurrence of superconductivity, in agreement with theoretical predictions. The temperature dependence of the specific heat in the vicinity of the first-order reentrant superconducting - ferromagnetic transition was computed by means of a simple model from the temperature dependence of the spontaneous magnetization of the Ho ions and was found to be in good agreement with the experimental data

Investigation of the charge exchange process π-d→π0nn

International Nuclear Information System (INIS)

Il-Tong Cheon.

1978-02-01

The transition rate has been calculated for the charge exchange of stopped π - in the deuteron. The present result is hω(π - d→π 0 nn)=0.695x10 -4 eV. Making use of the value hω(π - d→nn)=0.682 eV, which was previously obtained, estimated the branching ratio ω(π - d→π 0 nn)|ω(π - d→nn)=1.02x10 -4 has been estimated

Collision-induced stimulated photon echo generated at transition 0-1 on broad spectral line conditions

Science.gov (United States)

Rubtsova, N. N.; Gol'dort, V. G.; Ishchenko, V. N.; Khvorostov, E. B.; Kochubei, S. A.; Borisov, G. M.; Ledovskikh, D. V.; Reshetov, V. A.

2018-04-01

For the first time, the collision induced stimulated photon echo generated at transition 1S0 → 3 P1 of 174Yb (type 0-1) in the mixture of gases Yb  +  Xe was investigated in the presence of weak longitudinal magnetic field, with experimental parameters corresponding to broad spectral line conditions. Comparison of the experimental echo amplitude versus magnetic field strength dependence with the theoretical curve shows a very good agreement, giving rise to an improved estimate for the difference between alignment and orientation decay rates.

E-VPMS 1.0: Enhanced Vehicle Parking Monitoring System

Directory of Open Access Journals (Sweden)

Shian Lim Yeu

2018-01-01

Full Text Available Due to lack of vehicle parking slot in front of Block Q, Faculty of Electrical and Electronic Engineering (FKEE, UTHM, the enhanced vehicle parking monitoring system (E-VPMS 1.0 is developed to identify parking slots available in the parking area as well as to detect double parking problem. Once this system is implemented, time consume for searching available parking slots as well as double parking problem that may cause unwanted accident can be reduced. In the development of E-VPMS 1.0 system, whole system are designed and developed in three different phases; which are video processing phase, login and registration phase, and webview development phase. In video processing phase, video sources are processed through few video processing function. In login and registration phase, series of webpage function have been created that accessible in both smartphone and laptop. While, in webview development phase, webview function have been developed and through this function, content of E-VPMS 1.0 system can be displayed directly via web browser for both smartphone and laptop. Through E-VPMS 1.0, availability parking slots can be checked by registered user through input recorded video before entering the specific parking area. Other than that, performance analysis in terms of numbers of registered user and parking slot availability at different situations such as during peak event or normal event can be managed and controlled by admin through visualisation data method.

First-Order 0-π Quantum Phase Transition in the Kondo Regime of a Superconducting Carbon-Nanotube Quantum Dot

Directory of Open Access Journals (Sweden)

Romain Maurand

2012-02-01

Full Text Available We study a carbon-nanotube quantum dot embedded in a superconducting-quantum-interference-device loop in order to investigate the competition of strong electron correlations with a proximity effect. Depending on whether local pairing or local magnetism prevails, a superconducting quantum dot will exhibit a positive or a negative supercurrent, referred to as a 0 or π Josephson junction, respectively. In the regime of a strong Coulomb blockade, the 0-to-π transition is typically controlled by a change in the discrete charge state of the dot, from even to odd. In contrast, at a larger tunneling amplitude, the Kondo effect develops for an odd-charge (magnetic dot in the normal state, and quenches magnetism. In this situation, we find that a first-order 0-to-π quantum phase transition can be triggered at a fixed valence when superconductivity is brought in, due to the competition of the superconducting gap and the Kondo temperature. The superconducting-quantum-interference-device geometry together with the tunability of our device allows the exploration of the associated phase diagram predicted by recent theories. We also report on the observation of anharmonic behavior of the current-phase relation in the transition regime, which we associate with the two accessible superconducting states. Our results finally demonstrate that the spin-singlet nature of the Kondo state helps to enhance the stability of the 0 phase far from the mixed-valence regime in odd-charge superconducting quantum dots.

Adaptacao e validacao do WHODAS 2.0 em utentes com dor musculoesqueletica

Directory of Open Access Journals (Sweden)

Carla Silva

2013-08-01

Full Text Available OBJETIVO Validar a versão em português do World Health Organization Disability Assessment Schedule (WHODAS 2.0. MÉTODOS A versão original de 36 itens do WHODAS 2.0, administrada por entrevista, foi traduzida para o português de acordo com orientações internacionais e testada em nove participantes da população em geral. A versão em português foi administrada em 204 pacientes com patologia musculoesquelética. Foram coletados os dados sociodemográficos e de saúde dos pacientes, assim como o número de locais onde apresentavam dor e sua intensidade. O WHODAS 2.0 foi novamente administrado por um segundo entrevistador, um a três dias após a primeira entrevista, para avaliar a confiabilidade interavaliadores. A validade de constructo foi avaliada quanto a: capacidade do WHODAS 2.0 para diferenciar participantes com diferentes locais com dor e associação entre o WHODAS 2.0 e a intensidade da dor. A consistência interna também foi avaliada. RESULTADOS A versão portuguesa do WHODAS 2.0 teve fácil compreensão, apresentou boa consistência interna (α = 0,84 e confiabilidade interavaliadores (CCI = 0,95. Mostrou ser capaz de detectar diferenças estatisticamente significativas entre indivíduos com diferente número de locais com dor (p < 0,01 e indicar que maior incapacidade está associada à maior intensidade da dor (r = 0,44, p < 0,01, indicando validade de constructo. CONCLUSÕES A versão portuguesa do WHODAS 2.0 mostrou-se confiável e válida quando utilizada em pacientes com dor associada à patologia musculoesquelética.

First observation and branching fraction and decay parameter measurements of the weak radiative decay $\\Xi^0 \\to \\Lambda e^{+}e^{-}$

CERN Document Server

Batley, J Richard; Lazzeroni, C; Munday, D J; Patel, M; Slater, M W; Wotton, S A; Arcidiacono, R; Bocquet, G; Ceccucci, A; Cundy, Donald C; Doble, N; Falaleev, V; Gatignon, L; Gonidec, A; Grafstrm, P; Kubischta, Werner; Mikulec, I; Norton, A; Panzer-Steindel, B; Rubin, P; Wahl, H; Goudzovski, E; Khristov, P Z; Kekelidze, V D; Litov, L; Madigozhin, D T; Molokanova, N A; Potrebenikov, Yu K; Stoynev, S; Zinchenko, A I; Monnier, E; Swallow, E; Winston, R; Sacco, R; Walker, A; Baldini, W; Dalpiaz, P; Frabetti, P L; Gianoli, A; Martini, M; Petrucci, F; Savrié, M; Scarpa, M; Bizzeti, A; Calvetti, M; Collazuol, G; Iacopini, E; Lenti, M; Veltri, M; Ruggiero, G; Behler, M; Eppard, K; Eppard, M; Hirstius, A; Kleinknecht, K; Koch, U; Marouelli, P; Masetti, L; Moosbrugger, U; Morales-Morales, C; Peters, A; Wanke, R; Winhart, A; Dabrowski, A; Fonseca-Martin, T; Velasco, M; Anzivino, Giuseppina; Cenci, P; Imbergamo, E; Lamanna, G; Lubrano, P; Michetti, A; Nappi, A; Pepé, M; Valdata, M; Petrucci, M C; Piccini, M; Cerri, C; Costantini, F; Fantechi, R; Fiorini, L; Giudici, S; Mannelli, I; Pierazzini, G M; Sozzi, M; Cheshkov, C; Chèze, J B; De Beer, M; Debu, P; Gouge, G; Marel, Gérard; Mazzucato, E; Peyaud, B; Vallage, B; Holder, M; Maier, A; Ziolkowski, M; Biino, C; Cartiglia, N; Clemencic, M; Goy-Lopez, S; Marchetto, F; Menichetti, E; Pastrone, N; Wislicki, W; Dibon, Heinz; Jeitler, Manfred; Markytan, Manfred; Neuhofer, G; Widhalm, L

2007-01-01

The weak radiative decay $Xi^0 -> \\Lambda e^+ e^- $ has been detected for the first time. We find 412 candidates in the signal region, with an estimated background of $15pm 5$ events. We determine the branching fraction ${cal{B}}(\\Xi^0 -> \\Lambda e^+ e^- ) = [7.6pm 0.4({m stat})pm 0.4({m syst})pm 0.2({m norm})] imes 10^{-6}$, consistent with an internal bremsstrahlung process, and the decay asymmetry parameter $\\alpha_{\\Xi \\Lambda ee} = -0.8pm 0.2$, consistent with that of $\\Xi^0 -> \\Lambda \\gamma$. The charge conjugate reaction $\\overline{\\Xi^{0}} -> \\overline{\\Lambda} e^+ e^- $ has also been observed.

Crystal structure and magnetic properties of La2−x(Sr0.5Ca0.5)1+xMn2O7 (x=0.6, 0.8 and 1.0) Ruddlesden–Popper manganites

International Nuclear Information System (INIS)

Raju, K.; Song, M.S.; Lee, J.Y.

2014-01-01

Double layer perovskite (Ruddlesden–Popper) manganites with the nominal composition of La 2−x (Sr 0.5 Ca 0.5 ) 1+x Mn 2 O 7 (x=0.6, 0.8 and 1.0) were synthesized via a solid state reaction route. X-ray and neutron diffraction were performed at room temperature and the crystal structure was refined using the Rietveld method based on the space group, I4/mmm. The temperature variation of the susceptibility revealed a spin glass transition at 28 K for x=0.6, a charge ordering transition at 245 K and a Neel transition at 170 K for x=1.0. - Highlights: • Lanthanum based double layered manganites were prepared by doping with the same amounts of Sr and Ca. • X-ray and neutron diffraction were performed and the crystal structure was refined using the Rietveld method. • Different magnetic transitions were observed depending upon the doping concentration. • Qualitative explanation for the various observed phenomena was given

Effect of thermal strain on the ferroelectric phase transition in polycrystalline Ba0.5Sr0.5TiO3 thin films studied by Raman spectroscopy

International Nuclear Information System (INIS)

Tenne, D.A.; Soukiassian, A.; Xi, X.X.; Taylor, T.R.; Hansen, P.J.; Speck, J.S.; York, R.A.

2004-01-01

We have applied Raman spectroscopy to study the influence of thermal strain on the vibrational properties of polycrystalline Ba 0.5 Sr 0.5 TiO 3 films. The films were grown by rf magnetron sputtering on Pt/SiO 2 surface using different host substrates: strontium titanate, sapphire, silicon, and vycor glass. These substrates provide a systematic change in the thermal strain while maintaining the same film microstructure. From the temperature dependence of the ferroelectric A 1 soft phonon intensity, the ferroelectric phase transition temperature, T C , was determined. We found that T C decreases with increasing tensile stress in the films. This dependence is different from the theoretical predictions for epitaxial ferroelectric films. The reduction of the ferroelectric transition temperature with increasing biaxial tensile strain is attributed to the suppression of in-plane polarization due to the small lateral grain size in the films

Hybrid Perovskite Phase Transition and Its Ionic, Electrical and Optical Properties

Energy Technology Data Exchange (ETDEWEB)

Hoque, Md Nadim Ferdous; Islam, Nazifah; Zhu, Kai; Fan, Zhaoyang

2017-01-01

Hybrid perovskite solar cells (PSCs) under normal operation will reach a temperature above ~ 60 °C, across the tetragonal-cubic structural phase transition of methylammonium lead iodide (MAPbI₃). Whether the structural phase transition could result in dramatic changes of ionic, electrical and optical properties that may further impact the PSC performances should be studied. Herein, we report a structural phase transition temperature of MAPbI₃thin film at ~ 55 °C, but a striking contrast occurred at ~ 45 °C in the ionic and electrical properties of MAPbI₃due to a change of the ion activation energy from 0.7 eV to 0.5 eV. The optical properties exhibited no sharp transition except for the steady increase of the bandgap with temperature. It was also observed that the activation energy for ionic migration steadily increased with increased grain sizes, and reduction of the grain boundary density reduced the ionic migration.

Study of electrical and magnetic properties of Pr0.6-xBixSr0.4MnO3 (x=0.20 and 0.25)

Science.gov (United States)

Daivajna, Mamatha D.; Rao, Ashok; Lin, W. J.; Kuo, Y. K.

2017-06-01

We have investigated the electrical and magnetic properties of Pr0.6-xBixSr0.4MnO3 (x=0.20 and 0.25) manganites. XRD data shows that the synthesized samples are single-phase and crystallize in the orthorhombic structure with Pnma space group. Resistivity measurements show that the sample with x=0.25 exhibits a thermally activated behavior for the entire temperature range. The magnetoresistance (MR) for the x=0.25 sample is as high as nearly 100% over a wide range of temperature, demonstrating its important technological application as a material for MR-based devices. From the magnetization measurements, two magnetic transitions viz. paramagnetic insulating to ferromagnetic metallic (PMI-FMM) transition at TC and the ferromagnetic metallic (FMM) to antiferromagnetic insulating (AFI) transition at Neel temperature TN were observe in both samples. The Curie temperature decreases with bismuth doping, while TN increases with Bi content. Most interestingly, the temperature variation of magnetization and resistivity shows hysteresis behavior across the transition for the x=0.20 sample.

Anomalous second ferromagnetic phase transition in Co{sub 0.08}Bi{sub 1.92}Se{sub 3} topological insulator

Energy Technology Data Exchange (ETDEWEB)

Zhang, Min, E-mail: zmzmi1987@163.com; Liu, Ligang; Yang, Hui

2016-09-05

We report the observation of ferromagnetism in topological insulator Co{sub 0.08}Bi{sub 1.92}Se{sub 3} single crystal. The structural, magnetic, and microstructure properties of Co{sub 0.08}Bi{sub 1.92}Se{sub 3} are investigated. The existence of complicated ferromagnetic ordering, indicates the anomalous second ferromagnetic phase transition below 30 K. Well-defined ferromagnetic hysteresis in the magnetization was found in the sample. The origin of bulk ferromagnetism in Co{sub 0.08}Bi{sub 1.92}Se{sub 3} is concerned with three aspects: Co cluster, RKKY interactions, and the spin texture of Co impurities. - Highlights: • The bulk ferromagnetism have been found in the C{sub o0.08}Bi{sub 1.92}Se{sub 3} single crystal. • The anomalous second ferromagnetic phase transition is found below 30 K. • The origin of bulk ferromagnetism in Co{sub 0.08}Bi{sub 1.92}Se{sub 3} is concerned with three aspects.

EXAFS study of Mn{sub 1.28}Fe{sub 0.67}P{sub 0.46}Si{sub 0.54} compound with first-order phase transition

Energy Technology Data Exchange (ETDEWEB)

L, Yingjie; Huliyageqi, B; Haschaolu, W; Song, Zhiqiang [Inner Mongolia Key Laboratory for Physics and Chemistry of Functional Materials, Physics and Electronic Information College, Inner Mongolia Normal University, Hohhot 010022 (China); Tegus, O, E-mail: tegusph@imnu.edu.cn [Inner Mongolia Key Laboratory for Physics and Chemistry of Functional Materials, Physics and Electronic Information College, Inner Mongolia Normal University, Hohhot 010022 (China); Nakai, Ikuo [Department of Electrical and Electronic Engineering, Tottori University, Tottori 680-8552 (Japan)

2014-10-15

Highlights: • We have investigated the Fe and Mn K edge XAFS spectra of the Mn{sub 1.28}Fe{sub 0.67}P{sub 0.46}Si{sub 0.54} compound at 25 K and 295 K. • The site occupation of the Fe and Mn atoms and local structure of Mn{sub 1.28}Fe{sub 0.67}P{sub 0.46}Si{sub 0.54} are determined. • The atomic distances between Fe–Fe in c-plane for the ferromagnetic state are larger than those in the paramagnetic state. - Abstract: The Fe{sub 2}P-type MnFe(P,Si) compounds are investigated by means of magnetic measurements and X-ray absorption fine structure spectroscopy. Magnetic measurements show that the Mn{sub 1.28}Fe{sub 0.67}P{sub 0.46}Si{sub 0.54} compound undergoes a first-order phase transition at the Curie temperature of 254 K. The Fe K-edge and Mn K-edge X-ray absorption fine structure spectra show that Mn atom mainly located at the 3g sites, while the 3f sites are occupied by Fe atoms and Mn atom randomly. The distances between the Fe atom and its nearest neighbor atoms in a triangle Fe–Mn–Fe change from 2.80 Å at 25 K to 2.74 Å at 300 K. On the other hand, the distances between Fe atom and its second neighbor atoms change from 4.06 Å at 25 K to 4.02 Å at 300 K.

Study of the multipionic modes e+e-→π+π-π0 and e+e-→π+π-π+π- at the Orsay storage ring ACO

International Nuclear Information System (INIS)

Cordier, A.

1978-03-01

The results obtained with the magnetic detector DMI at the Orsay storage ring ACO are presented for the reactions e + e - →π + π - π 0 from 750 to 1100 MeV and e + e - →π + π - π + π - from 810 to 1100 MeV in the centre of mass. The magnetic detector DM1 consists of four cylindrical multiwire proportional chambers with anode and cathode readout in a solenoid providing a field of 0.9 T. The data for e + e - →π + π - π 0 show without ambiguity an interference effect between the ω and phi mesons, however new measurement above the phi performed using kinematical analysis can only be explained by higher energy contribution. In addition, the parameters of the ω have been obtained with improved accuracy compared to other experiments, and particularly the branching ratio Bsub(ω→e + e - )=(6.75+-0.69)10 -5 . The cross section of e + e - →π + π - π + π - is also measured and particularly an upper limit on the branching of phi→π + π - π + π - given [fr

Implication of the observed e{sup +}e{sup -} → p anti pπ{sup 0} for studying the p anti p → ψ(3770)π{sup 0} process

Energy Technology Data Exchange (ETDEWEB)

Xu, Hao [Lanzhou University and Institute of Modern Physics of CAS, Research Center for Hadron and CSR Physics, Lanzhou (China); Lanzhou University, School of Physical Science and Technology, Lanzhou (China); Xie, Ju-Jun [Lanzhou University and Institute of Modern Physics of CAS, Research Center for Hadron and CSR Physics, Lanzhou (China); Chinese Academy of Sciences, Institute of Modern Physics, Lanzhou (China); Institute of Theoretical Physics, Chinese Academy of Sciences, State Key Laboratory of Theoretical Physics, Beijing (China); Liu, Xiang [Lanzhou University and Institute of Modern Physics of CAS, Research Center for Hadron and CSR Physics, Lanzhou (China); Lanzhou University, School of Physical Science and Technology, Lanzhou (China); Institute of Theoretical Physics, Chinese Academy of Sciences, State Key Laboratory of Theoretical Physics, Beijing (China)

2016-04-15

We study the charmonium p anti p → ψ(3770)π{sup 0} reaction using the effective Lagrangian approach where the contributions from well-established N* states are considered, and all parameters are fixed in the process of e{sup +}e{sup -} → p anti pπ{sup 0} at center of mass energy √(s) = 3.773 GeV. The experimental data on the line shape of the mass distribution of the e{sup +}e{sup -} → p anti pπ{sup 0} can be well reproduced. Based on the study of e{sup +}e{sup -} → p anti pπ{sup 0}, the total and differential cross sections of the p anti p → ψ(3770)π{sup 0} reaction are predicted. At the same time we evaluated also the cross sections of the p anti p → ψ(3686)π{sup 0} reaction. It is shown that the contribution of the nucleon pole to this reaction is largest close to the reaction threshold. However, the interference between nucleon pole and the other nucleon resonance can still change the angle distributions significantly. Those theoretical results may be tested by the future experiments at PANDA. (orig.)

Spin-Polarization-Induced Preedge Transitions in the Sulfur K-Edge XAS Spectra of Open-Shell Transition-Metal Sulfates: Spectroscopic Validation of σ-Bond Electron Transfer.

Science.gov (United States)

Frank, Patrick; Szilagyi, Robert K; Gramlich, Volker; Hsu, Hua-Fen; Hedman, Britt; Hodgson, Keith O

2017-02-06

Sulfur K-edge X-ray absorption spectroscopy (XAS) spectra of the monodentate sulfate complexes [M II (itao)(SO 4 )(H 2 O) 0,1 ] (M = Co, Ni, Cu) and [Cu(Me 6 tren)(SO 4 )] exhibit well-defined preedge transitions at 2479.4, 2479.9, 2478.4, and 2477.7 eV, respectively, despite having no direct metal-sulfur bond, while the XAS preedge of [Zn(itao)(SO 4 )] is featureless. The sulfur K-edge XAS of [Cu(itao)(SO 4 )] but not of [Cu(Me 6 tren)(SO 4 )] uniquely exhibits a weak transition at 2472.1 eV, an extraordinary 8.7 eV below the first inflection of the rising K-edge. Preedge transitions also appear in the sulfur K-edge XAS of crystalline [M II (SO 4 )(H 2 O)] (M = Fe, Co, Ni, and Cu, but not Zn) and in sulfates of higher-valent early transition metals. Ground-state density functional theory (DFT) and time-dependent DFT (TDDFT) calculations show that charge transfer from coordinated sulfate to paramagnetic late transition metals produces spin polarization that differentially mixes the spin-up (α) and spin-down (β) spin orbitals of the sulfate ligand, inducing negative spin density at the sulfate sulfur. Ground-state DFT calculations show that sulfur 3p character then mixes into metal 4s and 4p valence orbitals and various combinations of ligand antibonding orbitals, producing measurable sulfur XAS transitions. TDDFT calculations confirm the presence of XAS preedge features 0.5-2 eV below the rising sulfur K-edge energy. The 2472.1 eV feature arises when orbitals at lower energy than the frontier occupied orbitals with S 3p character mix with the copper(II) electron hole. Transmission of spin polarization and thus of radical character through several bonds between the sulfur and electron hole provides a new mechanism for the counterintuitive appearance of preedge transitions in the XAS spectra of transition-metal oxoanion ligands in the absence of any direct metal-absorber bond. The 2472.1 eV transition is evidence for further radicalization from copper(II), which

Towards Precision Measurement of the 21S0-31D2 Two-Photon Transition in Atomic Helium

Science.gov (United States)

Huang, Yi-Jan; Guan, Yu-Chan; Suen, Te-Hwei; Wang, Li-Bang; Shy, Jow-Tsong

2017-04-01

We intend to accurately measure the frequency for 2S-3D two-photon transition and to deduce the 2S ionization energy to an accuracy below 100 kHz from the theoretical calculation of the 3D state. In this talk, we present a precision measurement of the 21S0 -31D2 two-photon transition in atomic helium at 1009 nm. A master oscillator power amplifier (MOPA) is seeded by an external cavity diode laser (ECDL) is constructed to generate more than 700 mW laser power with TEM00 beam profile at 1009 nm. To observe the two-photon transition, a helium cell is placed inside a power enhancement optical cavity and the helium atoms at 21S metastable level are prepared by a pulsed RF discharge and monitor the 668 nm 31D2 to 21P1 fluorescence after RF discharge is turned off . The absolute frequency metrology of the ECDL is carried out by an Er-fiber optical frequency comb (OFC). The two-photon spectrum is obtained by tuning the repetition frequency of the OFC. The 21S0-31D2 frequency is determined to be 594414291.967 (80) MHz in He-4. More results will be presented at the annual meeting.

Precise Extraction of the Neutron Magnetic Form Factor from Quasi-elastic 3He(pol)(e(pol),e') at Q2 = 0.1-0.6 (GeV/c)2

International Nuclear Information System (INIS)

Jens-ole Hansen; Brian Anderson; Leonard Auerbach; Todd Averett; William Bertozzi; Tim Black; John Calarco; Lawrence Cardman; Gordon Cates; Zhengwei Chai; Jiang-Ping Chen; Seonho Choi; Eugene Chudakov; Steve Churchwell; G Corrado; Christopher Crawford; Daniel Dale; Alexandre Deur; Pibero Djawotho; Dipangkar Dutta; John Finn; Haiyan Gao; Ronald Gilman; Oleksandr Glamazdin; Charles Glashausser; Walter Gloeckle; Jacek Golak; Javier Gomez; Viktor Gorbenko; F. Hersman; Douglas Higinbotham; Richard Holmes; Calvin Howell; Emlyn Hughes; Thomas Humensky; Sebastien Incerti; Piotr Zolnierczuk; Cornelis De Jager; John Jensen; Xiaodong Jiang; Cathleen Jones; Mark Jones; R Kahl; H Kamada; A Kievsky; Ioannis Kominis; Wolfgang Korsch; Kevin Kramer; Gerfried Kumbartzki; Michael Kuss; Enkeleida Lakuriqi; Meihua Liang; Nilanga Liyanage; John LeRose; Sergey Malov; Demetrius Margaziotis; Jeffery Martin; Kathy McCormick; Robert McKeown; Kevin McIlhany; Zein-Eddine Meziani; Robert Michaels; Greg Miller; Joseph Mitchell; Sirish Nanda; Emanuele Pace; Tina Pavlin; Gerassimos Petratos; Roman Pomatsalyuk; David Pripstein; David Prout; Ronald Ransome; Yves Roblin; Marat Rvachev; Giovanni Salme; Michael Schnee; Charles Seely; Taeksu Shin; Karl Slifer; Paul Souder; Steffen Strauch; Riad Suleiman; Mark Sutter; Bryan Tipton; Luminita Todor; M Viviani; Branislav Vlahovic; John Watson; Claude Williamson; H Witala; Bogdan Wojtsekhowski; Feng Xiong; Wang Xu; Jen-chuan Yeh

2006-01-01

We have measured the transverse asymmetry A T' in the quasi-elastic 3 /rvec He/(/rvec e/,e') process with high precision at Q 2 -values from 0.1 to 0.6 (GeV/c) 2 . The neutron magnetic form factor G M n was extracted at Q 2 -values of 0.1 and 0.2 (GeV/c) 2 using a non-relativistic Faddeev calculation which includes both final-state interactions (FSI) and meson-exchange currents (MEC). Theoretical uncertainties due to the FSI and MEC effects were constrained with a precision measurement of the spin-dependent asymmetry in the threshold region of 3 /rvec He/(/rvec e/,e'). We also extracted the neutron magnetic form factor G M n at Q 2 -values of 0.3 to 0.6 (GeV/c) 2 based on Plane Wave Impulse Approximation calculations

Can quantum transition state theory be defined as an exact t = 0+ limit?

Science.gov (United States)

Jang, Seogjoo; Voth, Gregory A.

2016-02-01

The definition of the classical transition state theory (TST) as a t → 0+ limit of the flux-side time correlation function relies on the assumption that simultaneous measurement of population and flux is a well defined physical process. However, the noncommutativity of the two measurements in quantum mechanics makes the extension of such a concept to the quantum regime impossible. For this reason, quantum TST (QTST) has been generally accepted as any kind of quantum rate theory reproducing the TST in the classical limit, and there has been a broad consensus that no unique QTST retaining all the properties of TST can be defined. Contrary to this widely held view, Hele and Althorpe (HA) [J. Chem. Phys. 138, 084108 (2013)] recently suggested that a true QTST can be defined as the exact t → 0+ limit of a certain kind of quantum flux-side time correlation function and that it is equivalent to the ring polymer molecular dynamics (RPMD) TST. This work seeks to question and clarify certain assumptions underlying these suggestions and their implications. First, the time correlation function used by HA as a starting expression is not related to the kinetic rate constant by virtue of linear response theory, which is the first important step in relating a t = 0+ limit to a physically measurable rate. Second, a theoretical analysis calls into question a key step in HA's proof which appears not to rely on an exact quantum mechanical identity. The correction of this makes the true t = 0+ limit of HA's QTST different from the RPMD-TST rate expression, but rather equal to the well-known path integral quantum transition state theory rate expression for the case of centroid dividing surface. An alternative quantum rate expression is then formulated starting from the linear response theory and by applying a recently developed formalism of real time dynamics of imaginary time path integrals [S. Jang, A. V. Sinitskiy, and G. A. Voth, J. Chem. Phys. 140, 154103 (2014)]. It is shown

QCD factorizations in γ*γ*->ρL0ρL0

International Nuclear Information System (INIS)

Pire, B.; Segond, M.; Szymanowski, L.; Wallon, S.

2006-01-01

We calculate the lowest order QCD amplitude, i.e. the quark exchange contribution, to the forward production amplitude of a pair of longitudinally polarized ρ mesons in the scattering of two virtual photons γ*(Q 1 )γ*(Q 2 )->ρ L 0 ρ L 0 . We show that the scattering amplitude simultaneously factorizes in two quite different ways: the part with transverse photons is described by the QCD factorization formula involving the generalized distribution amplitude of two final ρ mesons, whereas the part with longitudinally polarized photons takes the QCD factorized form with the γ L *->ρ L 0 transition distribution amplitude. Perturbative expressions for these, in general, non-perturbative functions are obtained in terms of the ρ-meson distribution amplitude

Status of BNL E791: Study of very rare KL0 decays

International Nuclear Information System (INIS)

McFarlane, W.K.

1989-01-01

BNL E791 is a search for the lepton-number non-conserving decay K L 0 → μe. During the 1988 run, the apparatus was also sensitive to the decays K L 0 → μμ, K L 0 → ee, and K L 0 → π 0 ee. Preliminary limits on the branching fractions from this run are: B(K L 0 → μe) -10 and B(K L 0 → ee) -10 . For the decay K L 0 → μμ, we identified 87 candidate events. We expect to reach a single-event sensitivity in the 10 -11 range in the future. 10 refs., 3 figs

E2 and M1 transition strengths in heavy deformed nuclei revisited

International Nuclear Information System (INIS)

Draayer, J.P.; Popa, G.; Hirsch, J.G.; Vargas, C.E.

2003-01-01

An update on the status of pseudo-SU(3) shell-model calculations in strongly deformed nuclei in the rare earth region is presented. Representative results for energy levels as well as E2 (quadrupole) and M1 (scissors) transitions strengths in 162 Dy (even-even) and 163 Dy (odd-mass) are given. The calculations use realistic single-particle energies and quadrupole-quadrupole and pairing interaction strengths fixed from systematics. The strengths of rotor-like terms included in the Hamiltonian- all small relative to the other terms in the interaction were adjusted to give an overall best fit to the energy spectra. The results present a paradox: for even-even nuclei (integer angular momentum) non-zero pseudo-spin configurations seems to be unimportant while for the odd-mass systems (half-integer angular momentum) pseudo-spin mixing is essential as spin-flip couplings appear to dominate the M1 transition strengths. (Author)

Two- to one-phonon E3 transition strength in {sup 148}Gd

Energy Technology Data Exchange (ETDEWEB)

Piiparinen, M [Niels Bohr Institute, Tandem Accelerator Laboratory, Roskilde (Denmark); [Jyvaeskylae Univ. (Finland). Dept. of Physics; Atac, A; Nyberg, J; Ramsoy, T; Sletten, G [Niels Bohr Institute, Tandem Acceleratory Laboratory, Roskile, (Denmark); Virtanen, A; Muller, D [Jyvaeskylae Univ. (Finland). Dept. of Physics; Kleinheinz, P [Forschungszentrum Juelich GmbH (Germany). Inst. fuer Kernphysik; Blomqvist, J [Manne Siegbahn Inst. of Physics, Stockholm (Sweden)

1992-08-01

In a plunger experiment the mean life of the ({nu} f{sub 6}{sup 2}x3{sup -}x3{sup -})12{sup +} state at 3.981 MeV in {sub 64}{sup 148}Gd{sub 84} was measured as {tau}=83(10)ps, giving 77(11)B{sub w} for the 1286 keV 12{sup +} {yields} 9{sup -} E3 transition rate, which confirms the double-octupole character of the 12{sup +} state. The observed deviations in energy and transition rate from harmonic vibration are shown to be caused by the exclusion principle acting between nucleons in the two phonons and are related to the dominant contributions to the {sup 148}Gd octupole phonon of the low-lying {Delta}l={Delta}j=3 proton- and neutron in-shell 3{sup -} excitations which are of vital significance for the octupole mode in open-shell nuclei. (author). 17 refs., 2 figs.

Supplementation with 0.1% and 2% vitamin e in diabetic rats: analysis of myenteric neurons immunostained for myosin-V and nNOS in the jejunum Suplementação com vitamina E 0,1% e 2% em ratos diabéticos: análise de neurônios mioentéricos imunomarcados para miosina-V e nNOS no jejuno

Directory of Open Access Journals (Sweden)

Eleandro Aparecido Tronchini

2012-12-01

Full Text Available CONTEXT: Diabetes mellitus is a disease characterized by hyperglycemia that, when allowed to progress long-term untreated, develops vascular and neurological complications, which are responsible for the development of alterations in the enteric nervous system in diabetic patients. In the gastrointestinal tract, diabetes mellitus promotes motor and sensory changes, and in the reflex function of this system, causing gastroparesis, diarrhea, constipation, megacolon, slow gastrointestinal transit, gastric stasis and dilation with decreased or increased peristaltic contractions. Several studies have shown that oxidative stress is the main responsible for the vascular and neurological complications affecting the enteric nervous system of diabetics. OBJECTIVE: The effects of 0.1% and 2% vitamin E on myosin-V- and nNOS-immunoreactive neurons in the jejunum of diabetic rats were investigated. METHODS: Thirty rats were divided into the groups: normoglycemic, normoglycemic treated with 0.1% vitamin E, normoglycemic treated with 2% vitamin E, diabetic, diabetic treated with 0.1% vitamin E, and diabetic treated with 2% vitamin E. The neuronal density and areas of neuron cell bodies were determined. RESULTS: Diabetes (diabetic group significantly reduced the number of myosin-V-immunoreactive neurons compared with the normoglycemic group. The diabetic treated with 0.1% vitamin E and diabetic treated with 2% vitamin E groups did not exhibit a greater density than the D group (P>0.05. Nitrergic density did not change with diabetes (P>0.05. The areas of myosin-V- and nNOS-immunoreactive neurons significantly increased in the normoglycemic treated with 2% vitamin E and diabetic groups compared with the normoglycemic group. CONCLUSION: Supplementation with 2% vitamin E had a neurotrophic effect only in the area of myosin-V-immunoreactive neurons compared with the diabetic group.CONTEXTO: O diabetes mellitus (DM é uma doença caracterizada pela hiperglicemia que a

Strongly Coupled Magnetic and Electronic Transitions in Multivalent Strontium Cobaltites.

Science.gov (United States)

Lee, J H; Choi, Woo Seok; Jeen, H; Lee, H-J; Seo, J H; Nam, J; Yeom, M S; Lee, H N

2017-11-22

The topotactic phase transition in SrCoO x (x = 2.5-3.0) makes it possible to reversibly transit between the two distinct phases, i.e. the brownmillerite SrCoO 2.5 that is a room-temperature antiferromagnetic insulator (AFM-I) and the perovskite SrCoO 3 that is a ferromagnetic metal (FM-M), owing to their multiple valence states. For the intermediate x values, the two distinct phases are expected to strongly compete with each other. With oxidation of SrCoO 2.5 , however, it has been conjectured that the magnetic transition is decoupled to the electronic phase transition, i.e., the AFM-to-FM transition occurs before the insulator-to-metal transition (IMT), which is still controversial. Here, we bridge the gap between the two-phase transitions by density-functional theory calculations combined with optical spectroscopy. We confirm that the IMT actually occurs concomitantly with the FM transition near the oxygen content x = 2.75. Strong charge-spin coupling drives the concurrent IMT and AFM-to-FM transition, which fosters the near room-T magnetic transition characteristic. Ultimately, our study demonstrates that SrCoO x is an intriguingly rare candidate for inducing coupled magnetic and electronic transition via fast and reversible redox reactions.

Dalitz plot analyses of J/psi -> pi(+) pi(-) pi(0), J/psi -> K+ K- pi(0), and J/psi -> (KsK +/-)-K-0 pi(-/+) produced via e (+) e (-) annihilation with initial-state radiation

NARCIS (Netherlands)

Lees, J. P.; Poireau, V.; Tisserand, V.; Grauges, E.; Palano, A.; Eigen, G.; Brown, D. N.; Kolomensky, Yu. G.; Fritsch, M.; Schroeder, T.; Hearty, C.; Mattison, T. S.; McKenna, J. A.; So, R. Y.; Blinov, V. E.; Buzykaev, A. R.; Druzhinin, V. P.; Golubev, V. B.; Kravchenko, E. A.; Onuchin, A. P.; Serednyakov, S. I.; Skovpen, Yu. I.; Solodov, E. P.; Todyshev, K. Yu.; Lankford, A. J.; Gary, J. W.; Long, O.; Eisner, A. M.; Lockman, W. S.; Vazquez, W. Panduro; Chao, D. S.; Echenard, B.; Flood, K. T.; Hitlin, D. G.; Miyashita, T. S.; Ongmongkolkul, P.; Rohrken, M.; Huard, Z.; Meadows, B. T.; Pushpawela, B. G.; Sokoloff, M. D.; Sun, L.; Smith, J. G.; Wagner, S. R.; Bernard, D.; Verderi, M.; Bettoni, D.; Bozzi, C.; Calabrese, R.; Cibinetto, G.; Fioravanti, E.; Garzia, I.; Luppi, E.; Santoro, V.; Calcaterra, A.; de Sangro, R.; Finocchiaro, G.; Martellotti, S.; Patteri, P.; Peruzzi, I. M.; Piccolo, M.; Rotondo, M.; Zallo, A.; Passaggio, S.; Patrignani, C.; Lacker, H. M.; Bhuyan, B.; Szczepaniak, A. P.; Mallik, U.; Cochran, J.; Prell, S.; Ahmed, H.; Pennington, M. R.; Gritsan, A. V.; Arnaud, N.; Davier, M.; Le Diberder, F.; Lutz, A. M.; Wormser, G.; Lange, D. J.; Wright, D. M.; Coleman, J. P.; Gabathuler, E.; Hutchcroft, D. E.; Payne, D. J.; Touramanis, C.; Bevan, A. J.; Di Lodovico, F.; Sacco, R.; Cowan, G.; Banerjee, Sw.; Brown, D. N.; Davis, C. L.; Denig, A. G.; Gradl, W.; Griessinger, K.; Hafner, A.; Schubert, K. R.; Barlow, R. J.; Lafferty, G. D.; Cenci, R.; Jawahery, A.; Roberts, D. A.; Cowan, R.; Robertson, S. H.; Dey, B.; Neri, N.; Palombo, F.; Cheaib, R.; Cremaldi, L.; Godang, R.; Summers, D. J.; Taras, P.; De Nardo, G.; Sciacca, C.; Raven, G.; Jessop, C. P.; LoSecco, J. M.; Honscheid, K.; Kass, R.; Gaz, A.; Margoni, M.; Posocco, M.; Simi, G.; Simonetto, F.; Stroili, R.; Akar, S.; Ben-Haim, E.; Bomben, M.; Bonneaud, G. R.; Calderini, G.; Chauveau, J.; Marchiori, G.; Ocariz, J.; Biasini, M.; Manoni, E.; Rossi, A.; Batignani, G.; Bettarini, S.; Carpinelli, M.; Casarosa, G.; Chrzaszcz, M.; Forti, F.; Giorgi, M. A.; Lusiani, A.; Oberhof, B.; Paoloni, E.; Rama, M.; Rizzo, G.; Walsh, J. J.; Smith, A. J. S.; Anulli, F.; Faccini, R.; Ferrarotto, F.; Ferroni, F.; Pilloni, A.; Piredda, G.; Buenger, C.; Dittrich, S.; Gruenberg, O.; Hess, M.; Leddig, T.; Voss, C.; Waldi, R.; Adye, T.; Wilson, F. F.; Emery, S.; Vasseur, G.; Aston, D.; Cartaro, C.; Convery, M. R.; Dorfan, J.; Dunwoodie, W.; Ebert, M.; Field, R. C.; Fulsom, B. G.; Graham, M. T.; Hast, C.; Innes, W. R.; Kim, P.; Leith, D. W. G. S.; Luitz, S.; MacFarlane, D. B.; Muller, D. R.; Neal, H.; Ratcliff, B. N.; Roodman, A.; Sullivan, M. K.; Va'vra, J.; Wisniewski, W. J.; Purohit, M. V.; Wilson, J. R.; Randle-Conde, A.; Sekula, S. J.; Bellis, M.; Burchat, P. R.; Puccio, E. M. T.; Alam, M. S.; Ernst, J. A.; Gorodeisky, R.; Guttman, N.; Peimer, D. R.; Soffer, A.; Spanier, S. M.; Ritchie, J. L.; Schwitters, R. F.; Izen, J. M.; Lou, X. C.; Bianchi, F.; De Mori, F.; Filippi, A.; Gamba, D.; Lanceri, L.; Vitale, L.; Martinez-Vidal, F.; Oyanguren, A.; Albert, J.; Beaulieu, A.; Bernlochner, F. U.; Kowalewski, R.; Lueck, T.; Nugent, I. M.; Roney, J. M.; Sobie, R. J.; Tasneem, N.; Gershon, T. J.; Harrison, P. F.; Latham, T. E.; Prepost, R.

2017-01-01

We study the processes e+e−→γISRJ/ψ, where J/ψ→π+π−π0, J/ψ→K+K−π0, and J/ψ→K 0 SK±π∓ using a data sample of 519  fb−1 recorded with the BABAR detector operating at the SLAC PEP-II asymmetric-energy e+e− collider at center-of-mass energies at and near the Υ(nS) (n=2,3,4) resonances. We measure the

Radiative rates for E1, E2, M1 and M2 transitions in Fe X

International Nuclear Information System (INIS)

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

2004-01-01

Energies of the 54 levels belonging to the (1s 2 2s 2 2p 6 ) 3s 2 3p 5 , 3s3p 6 , 3s 2 3p 4 3d and 3s3p 5 3d configurations of Fe X have been calculated using the GRASP code of Dyall and colleagues (1989). Additionally, radiative rates, oscillator strengths, and line strengths are calculated for all electric dipole (E1), magnetic dipole (M1), electric quadrupole (E2), and magnetic quadrupole (M2) transitions among these levels. Comparisons are made with results available in the literature, and the accuracy of the data is assessed. Our energy levels are estimated to be accurate to better than 3%, whereas results for other parameters are probably accurate to better than 20% . Additionally, the agreement between measured and calculated lifetimes is better than 10%. (authors)

Can one observe by μ SR the transition from uncorrelated to correlated spin fluctuations? Example: Nd1.4Ce0.2Sr0.4CuO4-δ

International Nuclear Information System (INIS)

Pinkpank, M.; Amato, A.; Gygax, F.N.; Schenck, A.; Henggeler, W.; Fischer, P.

1997-01-01

μSR-measurements in ZF and LF on Nd 1.4 Ce 0.2 Sr 0.4 CuO 4-δ show a sharp increase of the depolarisation rate (λ) below ∼ 2K. This increase can be explained by the transition from uncorrelated to correlated spin fluctuations, which is in agreement with results obtained by neutron scattering

Far infrared near normal specular reflectivity of Nix(SiO2)1-x (x = 1.0, 0.84, 0.75, 0.61, 0.54, 0.28) granular films

KAUST Repository

Massa, Né stor E.; Denardin, Juliano C.; Socolovsky, Leandro M.; Knobel, Marcelo; De La Cruz, Fernando Pablo; Zhang, Xixiang

2010-01-01

of transition metal granular films with different metal fractions against what is known for conducting oxides. Films for Nix(SiO2)1-x (x = 1.0, 0.84, 0.75, 0.61, 0.54, 0.28) were studied by temperature dependent far infrared measurements. While for pure Ni

Virtuality Distributions in application to gamma gamma* to pi^0 Transition Form Factor at Handbag Level

Energy Technology Data Exchange (ETDEWEB)

Radyushkin, Anatoly V. [ODU, JLAB

2014-07-01

We outline basics of a new approach to transverse momentum dependence in hard processes. As an illustration, we consider hard exclusive transition process gamma*gamma -> to pi^0 at the handbag level. Our starting point is coordinate representation for matrix elements of operators (in the simplest case, bilocal O(0,z)) describing a hadron with momentum p. Treated as functions of (pz) and z^2, they are parametrized through a virtuality distribution amplitude (VDA) Phi (x, sigma), with x being Fourier-conjugate to (pz) and sigma Laplace-conjugate to z^2. For intervals with z^+=0, we introduce transverse momentum distribution amplitude (TMDA) Psi (x, k_\\perp), and write it in terms of VDA Phi (x, \\sigma). The results of covariant calculations, written in terms of Phi (x sigma) are converted into expressions involving Psi (x, k_\\perp. Starting with scalar toy models, we extend the analysis onto the case of spin-1/2 quarks and QCD. We propose simple models for soft VDAs/TMDAs, and use them for comparison of handbag results with experimental (BaBar and BELLE) data on the pion transition form factor. We also discuss how one can generate high-k_\\perp tails from primordial soft distributions.

Releasing metal catalysts via phase transition: (NiO)0.05-(SrTi0.8Nb0.2O3)0.95 as a redox stable anode material for solid oxide fuel cells.

Science.gov (United States)

Xiao, Guoliang; Wang, Siwei; Lin, Ye; Zhang, Yanxiang; An, Ke; Chen, Fanglin

2014-11-26

Donor-doped perovskite-type SrTiO3 experiences stoichiometric changes at high temperatures in different Po2 involving the formation of Sr or Ti-rich impurities. NiO is incorporated into the stoichiometric strontium titanate, SrTi0.8Nb0.2O3-δ (STN), to form an A-site deficient perovskite material, (NiO)0.05-(SrTi0.8Nb0.2O3)0.95 (Ni-STN), for balancing the phase transition. Metallic Ni nanoparticles can be released upon reduction instead of forming undesired secondary phases. This material design introduces a simple catalytic modification method with good compositional control of the ceramic backbones, by which transport property and durability of solid oxide fuel cell anodes are largely determined. Using Ni-STN as anodes for solid oxide fuel cells, enhanced catalytic activity and remarkable stability in redox cycling have been achieved. Electrolyte-supported cells with the cell configuration of Ni-STN-SDC anode, La0.8Sr0.2Ga0.87Mg0.13O3 (LSGM) electrolyte, and La0.6Sr0.4Co0.2Fe0.8O3 (LSCF) cathode produce peak power densities of 612, 794, and 922 mW cm(-2) at 800, 850, and 900 °C, respectively, using H2 as the fuel and air as the oxidant. Minor degradation in fuel cell performance resulted from redox cycling can be recovered upon operating the fuel cells in H2. Such property makes Ni-STN a promising regenerative anode candidate for solid oxide fuel cells.