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1.
The microstructure and magnetic properties of FePt films grown on Cr and CrW underlayers were investigated. The FePt films that deposited on Cr underlayer show (2 0 0) orientation and low coercivity because of the diffusion between FePt and Cr underlayer. The misfit between FePt magnetic layer and underlayer increases by small addition of W element in Cr underlayer or using a thin Mo intermediate layer, which is favorable for the formation of (0 0 1) orientation and the transformation of FePt from fcc to fct phase. A good FePt (0 0 1) texture was obtained in the films with Cr85W15 underlayer with substrate temperature of 400 °C. The FePt films deposited on Mo/Cr underlayer exhibit larger coercivity than that of the films grown on Pt/Cr85W15 because 5 nm Mo intermediate layer depressed the diffusion of Cr into magnetic layer. 相似文献
2.
Multilayer Fe55Pt45(20 nm)/Pt(5 nm)/Cr100 ? x W x (80 nm)/glass structures, in which the Fe55Pt45 magnetic film has a face-centered tetragonal (FCT) structure of the L10 phase with the (001) texture, have been prepared using magnetron sputtering. The microstructure and texture of the FePt films have been studied as functions of the W content in the Cr100 ? x W x sublayer, where 0 < x < 25. It has been established that an increase in the W ion concentration leads to the formation of the (200) texture in the Cr100 ? x sublayer and to an increase in the Cr lattice constant. This is accompanied by a decrease in the temperature at which the facecentered cubic phase transforms into the FCT phase of the FePt films as a result of the increase in tensile stresses along the a axis. It has been found that the coercivity of FePt films deposited on CrW substrates increases with increasing W content in the Cr100 ? x W x sublayer because the CrW alloy thus formed precludes diffusion between the FePt film and the CrW sublayer. An additional 5-nm-thick intermediate Pt layer is also deposited to suppress diffusion between the FePt and CrW layers. As a result, the highly textured FePt(001) films intended for ultra-high density magnetic information recording are deposited on a substrate heated to a temperature of 400°C and the Cr85W115 sublayer. 相似文献
3.
C. A. Nelson E. G. Barbagiovanni J. J. Berger E. K. Pueschel J. R. Wickman 《The European Physical Journal C - Particles and Fields》2006,45(1):121-138
Most of this paper consists of the derivation of general beam-referenced stage-two spin-correlation functions for the analysis
of top-antitop pair production at the Tevatron, at the Large Hadron Collider, and/or at an International Linear Collider.
However, for the charged-lepton plus jets reaction
, there is a simple three-angle spin-correlation function for the determination of the relative sign of or for the measurement
of a possible non-trivial phase between the two dominant λb=-1/2 helicity amplitudes for the t → W+b decay mode. For the CP-conjugate case, there is an analogous function and tests for
decay. These results make use of W-boson longitudinal-transverse interference.
Received: 24 June 2005, Revised: 10 August 2005, Published online: 3 November 2005 相似文献
4.
Chromium oxide condensates nearly spherical in shape ranging from 0.1 to 0.2 micron in diameter were fabricated by laser ablation on a Cr target at a very high power density of 1.8×1012 W/cm2 for a very rapid heating and cooling effect. Analytical electron microscopic observations of such spherical particulates revealed three types: (1) α-Cr2O3 single crystal with ( $\bar{1}101),(\bar{1}012)$ and (1 $\bar{2}10)$ facets, (2) spinel-like Cr3O4 polycrystals with spherulitic texture, i.e. a rather corrugated solidification front, (3) recrystallized Cr3O4 polycrystals derived from type 2 by radiant heating. The microstructure and phase difference among the particulates can be attributed to a varied extent of supercooling under the influence of rather complicated Cr2+ solute trapping of the molten and solid phases in the Cr3O4?O pseudo-binary in vacuum. The chromium oxide condensates being spherical yet full of facets, with significant internal compressive stress up to ca. 3.4 GPa according to Raman shift, and with UV-absorbance close to violet light due to the presence of internal stress and/or Cr2+, may have potential optoelectronic and catalytic applications. 相似文献
5.
The hyperfine structure of the 62 P 1/2 and 72 P 1/2 state of85Rb and87Rb and of the 62 P 3/2 state of87Rb has been investigated with optical double resonance at intermediate magnetic fields. The magnetic interaction constants,g j factors and lifetimes are: $$\begin{gathered} 6^2 P_{1/2} state: A\left( {^{85} Rb} \right) = 39.11\left( 3 \right) MHz,A\left( {^{87} Rb} \right) = 132.56 \left( 3 \right)MHz, \hfill \\ g_j = 0.6659\left( 3 \right), \tau = 1.14\left( {13} \right) \cdot 10^{ - 7} \sec , \hfill \\ 7^2 P_{1/2} state: A\left( {^{85} Rb} \right) = 17.68\left( 8 \right)MHz,A\left( {^{87} Rb} \right) = 59.92\left( 9 \right)MHz, \hfill \\ g_j = 0.6655\left( 5 \right), \hfill \\ 6^2 P_{3/2} state: g_j = 1.3337\left( {10} \right), \tau = 1.12\left( 8 \right) \cdot 10^{ - 7} \sec for ^{87} Rb. \hfill \\ \end{gathered} $$ From the hfs coupling constants of then 2 P multiplets a 11.5% core polarization contribution to the magnetic hfs of then 2 P 3/2 states is obtained, which is found to be independent from the main quantum numbern. The expectation values <r ?3> j for thenp valence electrons corrected for core polarization are compared with those derived from the2 P fine structure separation. Good agreement is achieved for allnp levels with the choice ofZ i =Z?3=34 for the effective nuclear charge number. The nuclear quadrupole moments of85Rb and87Rb are rederived on the basis of this more improved treatment for thep-electron-nucleus interaction yielding $$\begin{gathered} Q_N \left( {^{85} Rb} \right) = + 0.274\left( 2 \right) \cdot 10^{ - 24} cm^2 \hfill \\ Q_N \left( {^{85} Rb} \right) = + 0.132\left( 1 \right) \cdot 10^{ - 24} cm^2 \hfill \\ \end{gathered} $$ where the error does not include the remaining theoretical uncertainty of about 10%. 相似文献
6.
The energy spectrum of photons emitted in neutrino (antineutrino) scattering on electrons at Ev ? mv is calculated with the assumption that the neutral electron flow has an arbitrary (V, A) structure. The result obtained is generalized to the case of possible neutrino oscillations, \(v_e \begin{array}{*{20}c} { - \to } \\ { \leftarrow - } \\ \end{array} v_\mu , \overline v _e \begin{array}{*{20}c} { - \to } \\ { \leftarrow - } \\ \end{array} \overline v _\mu \) , at an arbitrary neutrino mixing angle. Using the Weinberg-Salam model (sin2θW = 0.23) estimates of the sections dσγ/dω and σγ are obtained with consideration of the reactor antineutrino flux \(\bar v_e \) . The contributions from charged and neutral lepton fluxes and their interference to dσγ/dω are compared. 相似文献
7.
A. Kreissl A. D. Hancock H. Koch Th. Köhler H. Poth U. Raich D. Rohmann a. Wolf L. Tauscher A. Nilsson M. Suffert M. Chardalas S. Dedoussis H. Daniel T. von Egidy F. J. Hartmann W. Kanert H. Plendl G. Schmidt J. J. Reidy 《Zeitschrift fur Physik C Particles and Fields》1988,37(4):557-561
A high-precision measurement of the finestructure splitting in the circular 11→10 X-ray transition of \(\bar p^{208} Pb\) was performed. The experimental value of 1199(5) eV is in agreement with QED calculations. From that value the magnetic moment of the antiproton was deduced to be ?2.8005(90)μ nucl. With this result the uncertainty of the previous world average value was reduced by a factor of ≈2. A comparison with the corresponding quantity of the proton now yields: \({{\left( {\mu _p - \left| {\left\langle {\mu _{\bar p} } \right\rangle } \right|} \right)} \mathord{\left/ {\vphantom {{\left( {\mu _p - \left| {\left\langle {\mu _{\bar p} } \right\rangle } \right|} \right)} {\mu _p }}} \right. \kern-0em} {\mu _p }} = \left( { - 2.4 \pm 2.9} \right) \times 10^{ - 3} \) . 相似文献
8.
The decay chain
is identified in a sample of 3.9 million hadronic Z decays collected with the OPAL detector at LEP. The branching ratio BR
is measured to be
for the J
P
=1+ (D0
1) state. For decays into the J
P
=2+ (D2
*0) state, an upper limit of 1.4 x 10-3 is placed on the branching ratio at the 95% confidence level.Received: 20 December 2002, Revised: 15 April 2003, Published online: 12 September 2003 相似文献
9.
G. Abbiendi et al. 《The European Physical Journal C - Particles and Fields》2006,45(2):307-335
The mass and width of the W boson are measured using e+e– → W+W– events from the data sample collected by the OPAL experiment at LEP at centre-of-mass energies between 170 GeV and 209 GeV.
The mass (mW) and width (ΓW) are determined using direct reconstruction of the kinematics of W+W– →
and W+W– →
events. When combined with previous OPAL measurements using W+W– →
events and the dependence on of the WW production cross-section at threshold, the results are determined to be
where the first error is statistical, the second systematic and the third due to uncertainties in the value of the LEP beam
energy. By measuring in the channel using several different determinations of the direction of jets with differing sensitivities
to soft particles, a limit is also obtained on possible final-state interactions due to colour reconnection effects inW+W– →
events. The consistency of the results for the W mass and width with those inferred from other electroweak parameters provides
an important test of the Standard Model of electroweak interactions.
Arrival of the final proofs: 28 November 2005
This paper is dedicated to the memory of Steve O'Neale 相似文献
10.
The width of the \(\tau\rightarrow\bar{K}^{*0}(892)\pi^{-}\nu_\tau\) decay is calculated within the Nambu–Jona-Lasinio model taking into account four channels of the formation of the \(\tau\rightarrow\bar{K}^{*0}(892)\pi^{-}\) pair—the contact interaction and three channels with intermediate axial-vector, vector, and pseudoscalar mesons. Leading contributions arise from the contact interaction and axial-vector channel with an intermediate ground-state K1(1270) meson. Our theoretical estimate adequately reproduces the measured \(\tau\rightarrow\bar{K}^{*0}(892)\pi^{-}\nu_\tau\) decay width. 相似文献
11.
K. S. Aleksandrov S. V. Misyul M. S. Molokeev V. N. Voronov 《Physics of the Solid State》2009,51(12):2505-2512
The structures of all three phases of the Rb2KInF6 crystal have been determined from the experimental X-ray diffraction data for the powder sample. The refinement of the profile
and structural parameters has been carried out by the technique implemented in the DDM program, which minimizes the differences
between the derivatives of the calculated and measured X-ray intensities over the entire profile of the X-ray diffraction
pattern. The results obtained have been discussed using the group-theoretical analysis of the complete order-parameter condensate,
which takes into account the critical and noncritical atomic displacements and permits the interpretation of the experimental
data obtained previously. It has been reliably established that the sequence of changes in the symmetry during phase transitions
in Rb2KInF6 can be represented as $
Fm\bar 3m\xrightarrow[{0,0,\phi }]{{11 - 9\left( {\Gamma _4^ + } \right)}}{{I114} \mathord{\left/
{\vphantom {{I114} {m\xrightarrow[{\left( {\psi ,\phi ,\phi } \right)}]{{11 - 9\left( {\Gamma _4^ + } \right) \oplus 10 - 3\left( {X_3^ + } \right)}}{{P12_1 } \mathord{\left/
{\vphantom {{P12_1 } {n1}}} \right.
\kern-\nulldelimiterspace} {n1}}}}} \right.
\kern-\nulldelimiterspace} {m\xrightarrow[{\left( {\psi ,\phi ,\phi } \right)}]{{11 - 9\left( {\Gamma _4^ + } \right) \oplus 10 - 3\left( {X_3^ + } \right)}}{{P12_1 } \mathord{\left/
{\vphantom {{P12_1 } {n1}}} \right.
\kern-\nulldelimiterspace} {n1}}}}
$
Fm\bar 3m\xrightarrow[{0,0,\phi }]{{11 - 9\left( {\Gamma _4^ + } \right)}}{{I114} \mathord{\left/
{\vphantom {{I114} {m\xrightarrow[{\left( {\psi ,\phi ,\phi } \right)}]{{11 - 9\left( {\Gamma _4^ + } \right) \oplus 10 - 3\left( {X_3^ + } \right)}}{{P12_1 } \mathord{\left/
{\vphantom {{P12_1 } {n1}}} \right.
\kern-\nulldelimiterspace} {n1}}}}} \right.
\kern-\nulldelimiterspace} {m\xrightarrow[{\left( {\psi ,\phi ,\phi } \right)}]{{11 - 9\left( {\Gamma _4^ + } \right) \oplus 10 - 3\left( {X_3^ + } \right)}}{{P12_1 } \mathord{\left/
{\vphantom {{P12_1 } {n1}}} \right.
\kern-\nulldelimiterspace} {n1}}}}
. 相似文献
12.
Q. Liang 《Applied Surface Science》2006,252(13):4628-4631
We report a pulsed laser deposition (PLD) growth of VMn/CoCrPt bilayer with a magnetic coercivity (Hc) of 2.2 kOe and a grain size of 12 nm. The effects of VMn underlayer on magnetic properties of CoCrPt layer were studied. The coercivity, Hc, and squareness, S, of VMn/CoCrPt bilayer, is dependent on the thickness of VMn. The grain size of the CoCrPt film can also be modified by laser parameters. High laser fluence used for CoCrPt deposition produces a smaller grain size. Enhanced Hc and reduced grain size in VMn/CoCrPt is explained by more pronounced surface phase segregation during deposition at high laser fluence. 相似文献
13.
K. Lang A. Bodek F. Borcherding N. Giokaris I. E. Stockdale P. Auchincloss R. Blair C. Haber S. Mishra E. Oltman M. Ruiz F. J. Sciulli M. Shaevitz W. H. Smith R. Zhu Y. K. Chu D. B. MacFarlane R. L. Messner D. B. Novikoff M. V. Purohit D. Garfinkle F. S. Merritt M. Oreglia P. Reutens R. Coleman H. E. Fisk Y. Fukushima O. Kerns B. Jin D. Levinthal T. Kondo W. Marsh P. A. Rapidis S. Segler R. Stefanski D. Theriot H. B. White D. Yovanovitch O. Fackler K. Jenkins 《Zeitschrift fur Physik C Particles and Fields》1987,33(4):483-503
Neutrino interactions with two muons in the final state have been studied using the Fermilab narrow band beam. A sample of 18v μ like sign dimuon events withP μ>9 GeV/c yields 6.6±4.8 events after backgroud subtraction and a prompt rate of (1.0±0.7)×10?4 per single muon event. The kinematics of these events are compared with those of the non-prompt sources. A total of 437v μ and 31 \(\bar v_\mu \) opposite sign dimuon events withP μ>4.3 GeV/c are used to measure the strange quark content of the nucleon: \(\kappa = {{2s} \mathord{\left/ {\vphantom {{2s} {\left( {\bar u + \bar d} \right) = 0.52_{ - 0.15}^{ + 0.17} \left( {or\eta _s \frac{{2s}}{{u + d}} = 0.075 \pm 0.019} \right) for 100< E_v< 230 GeV\left( {\left\langle {Q^2 } \right\rangle = {{23 GeV^2 } \mathord{\left/ {\vphantom {{23 GeV^2 } {c^2 }}} \right. \kern-0em} {c^2 }}} \right)}}} \right. \kern-0em} {\left( {\bar u + \bar d} \right) = 0.52_{ - 0.15}^{ + 0.17} \left( {or\eta _s \frac{{2s}}{{u + d}} = 0.075 \pm 0.019} \right) for 100< E_v< 230 GeV\left( {\left\langle {Q^2 } \right\rangle = {{23 GeV^2 } \mathord{\left/ {\vphantom {{23 GeV^2 } {c^2 }}} \right. \kern-0em} {c^2 }}} \right)}}\) using a charm semileptonic branching ratio of (10.9±1.4)% extracted from measurements ine + e ? collisions and neutrino emulsion data. 相似文献
14.
A model-independent analysis of anomalous gauge coupling constants of W
± bosons is presented and the corresponding restrictions on them and on the electromagnetic characteristics of W
± bosons following from the experiments on measuring the e+ e- ? W+ W- ? ( e