Effect of E × B electron drift and plasma discharge in dc magnetron sputtering plasma

Study of electron drift velocity caused by Etimes B motion is done with the help of a Mach probe in a dc cylindrical magnetron sputtering system at different plasma discharge parameters like discharge voltage, gas pressure and applied magnetic field strength. The interplay of the electron drift with the different discharge parameters has been investigated. Strong radial variation of the electron drift velocity is observed and is found to be maximum near the cathode and it decreases slowly with the increase of radial distance from the cathode. The sheath electric field, E measured experimentally from potential profile curve using an emissive probe is contributed to the observed radial variation of the electron drift velocity. The measured values of the drift velocities are also compared with the values from the conventional theory using the experimental values of electric and magnetic fields. This study of the drift velocity variation is helpful in providing a useful insight for determining the discharge conditions and parameters for sputter deposition of thin film.     

Spin observables of the reactions NN → Δ N and pd → Δ( pp )(1 S 0) in collinear kinematics

A general formalism for double and triple spin correlations of the reaction is developed for the case of collinear kinematics. A complete polarization experiment allowing one to reconstruct all four amplitudes describing this process is suggested. Furthermore, the spin observables of the inelastic charge-exchange reaction (pp)(¹ S ₀ are analyzed in collinear kinematics within the single pN-scattering mechanism involving the subprocess pn → Δ⁰ p. The full set of spin observables, related to the polarization of one or two initial particles and one final particle, is obtained in terms of three invariant amplitudes of the reaction pd → Δ(pp)(¹ S ₀) and the transition form factor d → (pp)(¹ S ₀). A complete polarization experiment for the reaction (pp)(¹ S ₀) is suggested which allows one to determine three independent combinations of the four amplitudes of the elementary subprocess . The text was submitted by the authors in English.     

Radial and spiral distortion of magnetic lenses with fields of the form B(z)αz

Both radial and spiral distortion of magnetic lens with the field distribution in the form B(z)αzⁿ are analyzed by means of Scherzer's formula. To estimate the performance of the image in electron microscope the dimensionless quality factors (F.Z. Marai, T. Mulvey, Sherzer's formula and the correction of spiral distortion in the electron microscope, Ultramicroscopy 2 (1977) 187–192.), for both radial and spiral distortion is calculated. The results have been compared with different projector lenses.     

Rare decays of Λ b → Λ γ and Λ b → Λ l + l ? in universal extra-dimension model

The exclusive weak decay of Λ _b →Λ γ and Λ _b →Λ l ⁺ l ⁻ are investigated in the Appelquist–Cheng–Dobrescu model, which is an extension of the standard model in the presence of universal extra dimensions. Employing the transition form factors obtained in the light-cone sum rules, we analyze how the invariant-mass distribution, the forward–backward asymmetry and the polarization asymmetry of the Λ baryon of these decay modes can be used to constrain the only additional free parameter with respect to the standard model, namely, the radius, R, of the extra dimension. Our results indicate that the Kaluza–Klein modes can lead to approximately 25% suppression of the branching ratio of Λ _b →Λ γ; however, their contributions can bring about 10% enhancement to the decay rate of Λ _b →Λ l ⁺ l ⁻. It is shown that in the present scenario the zero position of the forward–backward asymmetry of Λ _b →Λ μ ⁺ μ ⁻ is sensitive to the compactification parameter R, while the measurement of polarizations of Λ baryon in the Λ _b decays are not a useful tool to provide any valuable information for the universal extra-dimension model.     

A generalized Weyl—Wigner quantization scheme unifying P-Q and Q-P ordering and Weyl ordering of operators

By extending the usual Wigner operator to the s-parameterized one as 1/4π2 integral (dyduexp [iu(q-Q)+iy(p-P)+is/2yu]) from n=- ∞ to ∞ with s beng a,real parameter,we propose a generalized Weyl quantization scheme which accompanies a new generalized s-parameterized ordering rule.This rule recovers P-Q ordering,Q-P ordering,and Weyl ordering of operators in s = 1,1,0 respectively.Hence it differs from the Cahill-Glaubers’ ordering rule which unifies normal ordering,antinormal ordering,and Weyl ordering.We also show that in this scheme the s-parameter plays the role of correlation between two quadratures Q and P.The formula that can rearrange a given operator into its new s-parameterized ordering is presented.     

Dissipative Collapse in the Presence of Λ

We present the general junction conditions for the smooth matching of a spherically symmetric, shear-free spacetime to Vaidya’s outgoing metric across a four-dimensional time-like hypersurface in the presence of a cosmological constant. These results generalise earlier treatments by Santos and co-workers on radiating stellar models. We study the thermal evolution of a particular radiating model within the framework of extended irreversible thermodynamics.     

Semileptonic decays of B s 1, B s 2* , B s 0 and B s 1′

Stimulated by recent observations of the excited bottom–strange mesons B _s1 and B _s2^*, we calculate the semileptonic decays , which is relevant for the exploration of the potential of searching these semileptonic decays in experiment.     

Breakup of an oxygen nucleus to light fragments of mass number in the range A ? 4 in 16Op interactions at a momentum of 3.25 GeV/c per nucleon

New experimental data on the correlations of the yields of ⁴He and ²H nuclei in semi-inclusive reactions involving by the production of ³He and ³H mirror nuclei in ¹⁶Op collisions at a momentum of 3.25 GeV/c per nucleon are presented. The mean multiplicities of protons and neutrons appearing as fragments are found to be independent of the number of associated deuterons, this indicating that a considerable part of these fragments originate from the breakup of the alpha-particle clusters forming the oxygen nucleus.     

Leptoquark and vector-like quark extended model for simultaneousexplanation of W boson mass and muon g–2 anomalies

The CDF collaboration recently announced a new measurement result for the W boson mass, and it is in tension with the standard model prediction. In this paper, we explain this anomaly in the vector-like quark (VLQ) \begin{document}$ (X,T,B)_{L,R} $\end{document} and leptoquark (LQ) \begin{document}$ S_3 $\end{document} extended model. In this model, both the VLQ and LQ have positive corrections to the W boson mass. Moreover, it may be a solution to the \begin{document}$ (g-2)_{\mu} $\end{document} anomaly because of the chiral enhancements from top, T, and B quarks.     

The application of poly(N, N′-dibromo-N-ethyl-benzene-1,3-disulfonamide) and N, N, N′, N′-tetrabromobenzene-1,3-disulfonamide as catalysts for one-pot synthesis of 2-aryl-1-arylmethyl-1H-1,3-benzimidazoles and 1,5-benzodiazepines, and new reagents for synthesis of benzimidazoles

A new, facile, and efficient procedure for conjugate addition of indole and pyrrole with Michael acceptors have been developed for pulverization–activation reaction catalyzed by wet cyanuric chloride (2,4,6-trichloro-[1,3,5]-triazine or TCT) through grinding under solvent-free conditions at room temperature. Also, double-conjugate 1,4-addition of indoles to dibenzylidenacetones and conjugate addition of thiols with Michael acceptors using wet-TCT as catalyst is reported.     

Anomalies of the pyroelectric and dielectric properties of ferroelectric ceramics of the PbZr1- x Ti x O3 system with 0.06 ≤ x ≤ 0.35 at the R3 c ? R 3 m phase transition

The temperature dependences of the pyroelectric and dielectric properties of ferroelectric ceramics of the PbZr_{1 − x} Ti _x O₃ binary system with x = 0.06, 0.07, 0.08, 0.1, 0.15, 0.2, 0.25, 0.3, and 0.35 have been obtained synchronously for each sample in the range of the structural phase transition between the states with the symmetry space groups R3c ↔ R3m. It is established that the temperatures of this phase transition for unpolarized and polarized samples coincide in the range 0.06 ≤ x ≤ 0.15. In this case, the x−T phase diagram, constructed on the basis of the pyroelectric and dielectric data, is in excellent agreement with the X-ray diffraction data on single crystals in this concentration range. The effect of dc electric fields from 5 × 10⁵ V m⁻¹ did not lead to any temperature shifts of the R3c ↔ R3m phase transition for the compositions with 0.06 ≤ x ≤ 0.25. Original Russian Text ? Yu.N. Zakharov, A.G. Lutokhin, N.A. Korchagina, V.G. Kuznetsov, 2008, published in Izvestiya Rossiiskoi Akademii Nauk. Seriya Fizicheskaya, 2008, Vol. 72, No. 4, pp. 589–591.     

Λp femtoscopy in collisions of Ar + KCl at 1.76 A GeV with HADES

Results on Λp femtoscopy are reported at the lowest energy so far. At a beam energy of 1.76.A GeV, the reaction Ar + KCl was studied with HADES at SIS18/GSI. A high-statistics and high-purity Λ sample was collected, allowing for the investigation of Λp correlations at small relative momenta. The experimental correlation function is compared to corresponding model calculations allowing the determination of the space-time extent of the Λp emission source. The Λp radius is found significantly smaller than that for Au + Au/Pb + Pb collisions in the AGS, SPS and RHIC energy domains, but larger than that for electroproduction from He. Taking into account all available data, we find the Λp source radius to increase almost linearly with the number of participants to the power of one-third.     

Study of n=2,Δn=0 transition of Be-, B-, C-, N- and O-like sequence in the beam--foil spectrum of titanium

The foil-excited the spectrum of highly stripped titanium ions between 12-40 nm has been studied. Titanium ions of 80 and 120 MeV were provided by the HI-13 tandem accelerator at the China Institute of Atomic Energy. GIM-957 XUV-VUV monochromator was refocused to get highly-resolved spectra. Our experimental results and the published spectral data of laser-produced plasma show agreement in nearly all cases within ±0.03 nm. The spectra contained some weak or strong lines previously unclassified. These spectral lines mainly belong to 2s2p^2 for TiXVⅢ, 2p^3 for TiXVIII, 2s2p^3 for TiXVII, 2p^6 4p for Ti XII and 2p^6 3d for Ti XII transitions.     

J/ψ suppression vs centrality at forward and mid-rapidity in Au+Au collisions at RHIC in colour screening mechanism

We extend our previous formalism [Phys. Lett. B 656 45 (2007)] on J/ψ suppression at midrapidity using the colour screening framework. Our formalism is more general as the complete rapidity, transverse momentum and centrality dependence including J/ψ suppression at forward as well as mid-rapidity can be computed directly from it. We have assumed that QGP fluid is expanding obeying Bjorken’s boost invariant scaling law and bag model EOS is used. Sequential melting of χ _c (1P) as well as ψ′ (2S) higher resonances is incorporated. We find that our model shows a reasonable agreement with the mid and forward rapidity data. Furthermore, we observe a larger suppression at forward rapidity in our model which is again well supported by the PHENIX data.     

Crystal structure and properties of Bi1 ? x Ca x FeO3 and Bi1 ? x Ca x FeO1 ? x Ti x O3 solid solutions

Systems of solid solutions Bi_{1 − x} Ca _x FeO₃ (I) and Bi_{1 − x} CaxFeO_{1 − x} Ti _x O₃ (II) have been obtained and their properties have been studied using neutronography and M?ssbauer spectroscopy; magnetization and permittivity have been measured. It is shown that an increase in the concentration of calcium ions in system I for x > 0.2 changes rhombohedral distortions of a unit cell (space group R3c) to tetragonal distortions (space group I4/mcm), while rhombohedral distortions in system II for x > 0.2 are replaced by orthorhombic distortions (space group Pnma). Analysis of the crystal structure has revealed strong anisotropy in vibrations of Bi and O ions in system I compounds. Systems I and II are characterized by G-type antiferromagnetic ordering of magnetic moments. In system II, spontaneous magnetization associated with the Dzyaloshinskii-Moriya interaction has been detected. According to M?ssbauer spectroscopy data, iron ions in compounds I and II are in the trivalent state and charge compensation occurs due to the formation of oxygen vacancies. The permittivity increases with the calcium concentration. Original Russian Text ? I.O. Troyanchuk, D.V. Karpinsky, M.V. Bushinskii, O. Prokhnenko, M. Kopcevicz, R. Szymczak, J. Pietosa, 2008, published in Zhurnal éksperimental’noĭ i Teoreticheskoĭ Fiziki, 2008, Vol. 134, No. 1, pp. 105–112.     

Near-threshold production of a0(980) mesons in πN and NN collisions and a0-f0 mixing

We consider near-threshold a ₀(980)-meson production in πN and NN collisions. An effective Lagrangian approach with one-pion exchange is applied to analyze different contributions to the cross section for different isospin channels. The Reggeon exchange mechanism is also evaluated for comparison. The results from πN reactions are used to calculate the contribution of the a ₀ meson to the cross sections and invariant mass distributions of the reactions and pp → ppK ⁺ K ⁻. It is found that the experimental observation of a ₀ ⁺ mesons in the reaction is much more promising than the observation of a ₀ ⁰ mesons in the reaction pp → ppK ⁺ K ⁻. Effects of isospin violation in the reactions pN → da ₀, pd → ³He(³H)a ₀, and dd → ⁴Hea ₀, which are induced by a ₀(980)-f ₀(980) mixing, are also analyzed. From Yadernaya Fizika, Vol. 66, No. 1, 2003, pp. 155–174. Original English Text Copyright ? 2003 by Kondratyuk, Bratkovskaya, Grishina, Büscher, Cassing, Str?her. This article was submitted by the authors in English.     

Synthesis of Eu x Si6? z Al z O z N8? z green phosphor and?its?luminescent properties

Rare-earth-doped oxynitride or nitride compounds have been reported to be photoluminescent and may then serve as new phosphors because of their good thermal and chemical stabilities. In this work, Eu²⁺-doped β-SiAlON phosphor with a composition of Eu _x Si_6−z Al _z O _z N_8−z (x=0.018, z=0.23) was prepared by gas-pressured solid state reaction. The crystallinity and particle morphology of the prepared phosphor were characterized. The Stokes shift and zero-phonon line were calculated mathematically and estimated from the spectral data. The temperature dependence of photoluminescence was measured from 25 to 250°C. The prepared Eu²⁺-doped β-SiAlON green phosphor showed superior thermal quenching property compared to silicate (SrBaSiO₄:Eu²⁺) green phosphor. The white light-emitting diode (LED) back-lighting unit (BLU) using the prepared β-SiAlON:Eu²⁺ green phosphor exhibited higher color gamut than a commercial silicate phosphor.     

Inclusive production of charged pions, kaons and protons in υ(4S) decays

Using the detector ARGUS at thee ⁺ e ^– storage ring DORIS II, we have investigated inclusive momentum spectra of charged pions, kaons, and protons from decays of the (4S) meson. The kaon spectra have been measured in two independent ways, by coherently exploiting the detector's particle identification capabilities, and by detecting decays in-flight. The extracted mean multiplicities for charged hadrons are 7.17±0.05±0.14 pions, 1.56±0.03±0.05 kaons and 0.110±0.010±0.007 protons per (4S) decay, where pions and protons fromK _s ^o and decays have been subtracted.Supported in part by the Institute of Physics, University of Lund, Sweden     

Resonances in the pump-probe spectroscopy of Λ system in alkali atoms

We investigate resonances in the pump-probe spectroscopy of Λ configuration of levels in the hyperfine manifold of D ₂ transition of ¹³³Cs and ^a7Rb with specific reference to Autler-Townes splitting, dressed state resonances in double Λ system and electromagnetically induced transparency. As an application, a dark resonance based magnetometer is briefly discussed.     

CP -violation effects in the decays B ? → D * K *? and method for determining the weak phase γ

A method for determining the angle γ and the ratio of the amplitudes A _λ(B ⁻ → K ^*−) and A _λ)B ⁻ → D ^*0 K ^*−), r _Bλ, for all three vector-meson polarization states by using the decays B ^∓ → D ^* K ^*∓ is proposed. This method relies on the interference between the decays B ⁻ → D ^*0 K ^*− and B ⁻ → K ^*−, which arises if D ^*0 and decay to D ⁰/ π ⁰ and D ⁰/ γ, whereupon D ⁰ and mesons decay to common final hadron states. The doubly Cabibbo-suppressed modes of D ⁰-meson decay are chosen here to specify such final states. Original Russian Text ? V.A. Kovalchuk, 2007, published in Yadernaya Fizika, 2007, Vol. 70, No. 4, pp. 754–763.