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1.
The ultraviolet bands of mercury bromide have been excited in uncondensed discharge and photographed with a quartz Littrow spectrograph. The class II system, lying betweenλ 2900 å to 2700 å, suggested byWieland as due to the triatomic molecule, has been studied in detail and ascribed to the diatomic molecule. The bands in the regionλ 2900 å to 2770å have been analysed into two systems which may form the two components of a2 II ?2 σ electronic transition with a2 II interval equal to 969·4 cm?1. Another system most probably due to2 σ?2 σ has been observed in the regionλ 2770 to 2720.  相似文献   

2.
The Ultra violet bands of mercury chloride have been excited in uncondensed discharge and photographed with a quartz Littrow Spectrograph. The Class II system betweenλ 2900 to 2700 suggested by Wieland as due to the triatomic molecule has been studied in detail. In addition to the bands already recorded by previous investigators, a number of new bands has been recorded in the present investigation. A new vibrational analysis of these bands is given. The entire bands are ascribed to the longer wavelength component of2 π-2 ?, the other component being the system in the regionλ 2650 to 2400 with a2 π interval of 3335 cm?1 which is in keeping with the corresponding intervals obtained in the case of HgF and Hg I respectively. The following vibrational constants have been determined.Ν e Ω′ e Ω″ e 36346 cm?1 385 cm?1 292.5 cm?1  相似文献   

3.
The characteristics of an excimer radiation source pumped by a subnormal dc glow discharge in an Ar/Xe/Cl2 mixture with the source operating in a spectral range of 160–310 nm were studied. The emission intensities of the 175, 236, 258, and 308 nm bands due to the transitions ArCl (B-X), XeCl (D-X), Cl2 (D′-A′), and XeCl (B-X), respectively, were optimized in relation to the pressure, composition, and discharge current of the mixture.  相似文献   

4.
A new emission band system of S2 has been obtained in the region λ 3050–λ 2670 when sulphur is excited in a 30 mc/S. high frequency discharge from a 1/2 kW oscillator. The bands appear single sharp headed and are degraded towards red. Analysis of these new bands as belonging to a single system has led to the following vibrational formula.ν=36624·7+428·5(v′+1/2)?3·45(v′+1/2)2 ?699·2(v″+1/2)+3·2(v″+1/2)2. This system disignated as (b?x) is tentatively assigned to the electronic transition1 u + ?1 g + . The1 g + (x) state is found as the common lower state of three of the far ultraviolet systems of S2 recently reported byTanaka andOgawa.  相似文献   

5.
By the method of functional integration the two-point functionS F for the spinor model with the interaction\( - \lambda (\bar \psi \psi )^2 \) is calculated in a two-dimensional space-time. After Fourier-transformationS F (p) results as a power series with respect to 1/√λ. If we change the order of terms, we get a series in powers of γp. Each coefficient is a series in powers of 1/√λ. The first terms of this series are considered as a good approximation for bigλ. By reasons of convergence of the integrals we must displace the expansion centre of the series in powers ofγ p fromp 2=0 top 2=a 2.  相似文献   

6.
We consider mass-conserving self-similar solutions for Smoluchowski’s coagulation equation with kernel K(ξ,η)=(ξη) λ with λ∈(0,1/2). It is known that such self-similar solutions g(x) satisfy that x ?1+2λ g(x) is bounded above and below as x→0. In this paper we describe in detail via formal asymptotics the qualitative behavior of a suitably rescaled function h(x)=h λ x ?1+2λ g(x) in the limit λ→0. It turns out that \(h \sim 1+ C x^{\lambda/2} \cos(\sqrt{\lambda} \log x)\) as x→0. As x becomes larger h develops peaks of height 1/λ that are separated by large regions where h is small. Finally, h converges to zero exponentially fast as x→∞. Our analysis is based on different approximations of a nonlocal operator, that reduces the original equation in certain regimes to a system of ODE.  相似文献   

7.
The intensity of the first negative system ofN 2 + (B 2 Σ u + -X 2 Σ g + and of the second positive system ofN 2(C 3 Π u -B 3 Π g ) was observed in the discharge and in the afterglow as function of discharge current. An a. c. discharge in pure nitrogen was used at pressures of about 5 torr. The intensity of the first negative system ofN 2 + — in the discharge and in the afterglow — rises to a maximum and decreases with further increase of the discharge current. The afterglow intensity of the second positive system ofN 2 shows a maximum too. In the discharge, however, the intensity of the second positive system ofN 2 increases with increasing discharge current. The relative population of the vibrational levelsN v′ =i/N v′ =0 (i=1,2,3,4) of theB 2 Σ u + state ofN 2 + , in the discharge and in the afterglow, increases with increasing discharge current, while the relative population of the vibrational levelsN v′ =i/N v′ =0 (i=1, 2, 3, 4) of theC 3 Π u state ofN 2 reaches a maximum in the discharge. There seems to be evidence that the first negative system ofN 2 + is not excited by electron impact withN 2 molecules in ground state under the discharge conditions in question.  相似文献   

8.
In connection with recent assumptions, that weak vector-bosons might couple only toμ + μ ? currents (and not toe + e ?-ones) the question arises, how to check these bosons, since no collidingμ + μ ? beams are available. We have shown in this paper that this check could be performed by means of the resonance appearing in a pair production process fromμ-beams and that this process would work atμ-energies beyond 20 Bev.  相似文献   

9.
The low energy gamma-rays from neutron-capture in Lu 175 and Lu 176 have been investigated by means of the bent crystal-spectrometer at the DR-3-reactor at Risø. From the transitions in Lu 177 3 rotational bands have been determined. The levels of the (404)K=7/2+ groundstate rotational band are: 121,62 keV (I=9/2), 268,79keV (I=11/2), 440,66 keV (I=13/2), 636,22 keV (I=15/2), 854,34 keV (I=17/2). The level-sequence of the (514)K=9/2?-band is: 150,39 keV (I=9/2), 288,99 keV (I=11/2), 451,49 keV (I=13/2), 637,05 keV (I=15/2) and 844,88 keV (I=17/2). At 457,92 keV is the basis for the (402)K=5/2+-band the higher levels of which are 552,05 keV (I=7/2), 671,89 keV (I=9/2), 816,63 keV (I=11/2), 985,23 keV (I=13/2), 1176,73keV (I=15/2) and probably 1389,5 keV (I=17/2). The energies of the levels apart from the 1389 keV-level have an accuracy of 7×10?5. The energy differences between the 3 bands agree very well with the values expected from the Bohr-Mottelson-formulaE=A·I(I+1)+B·I 2(I+1)2. The calculated branching-ratios within the 3 bands are in fairly good agreement with the experimental values. Theg K -factors have been determined for 2 bands: It was found that for the (514)-bandg K =1,16±0,04 and for the (402)-bandg K =1,33±0,07.  相似文献   

10.
The investigation of the emission spectrum of NS molecule has been carried out by using a Littrow-type quartz spectrograph and a two meter normal incidence type vacuum spectrograph. Theγ-system (2 σ-2 π), in which only the bands havingv′=0 and 1 were known previously, has been extended tov′=4. TheδG values of the upper state do not show much regularity indicating some perturbation in this state. The vibrational constants for theΒ-system (2 δ-2 π) have also been modified slightly by observing more bands for this system. Four new systems, all of which have the ground state as their common lower state, have been observed in the ultraviolet and the vacuum ultraviolet regions.  相似文献   

11.
A Fourier transformation in a fractional dimensional space of order λ (0<λ≤1) is defined to solve the Schrödinger equation with Riesz fractional derivatives of order α. This new method is applied for a particle in a fractional δ-potential well defined by V(x)=?γ δ λ (x), where γ>0  and δ λ (x) is the fractional Dirac delta function. A complete solutions for the energy values and the wave functions are obtained in terms of the Fox H-functions. It is demonstrated that the eigen solutions are exist if 0<λ<α. The results for λ=1 and α=2 are in exact agreement with those presented in the standard quantum mechanics.  相似文献   

12.
Coriolis interaction between levels of two rotational bands in 172Yb with K π = 2+ and 3+ and in 168Er between levels with K π = 0?, 1?, and 2? is studied. The values of the interaction parameters are obtained. The mutual influence of two bands in 162Dy with ΔK = 2, K i π = 0 2 + and 2 1 + due to Coriolis interaction is demonstrated.  相似文献   

13.
In the multiquantum approximation of the orthogonal scheme, specific calculations for the energies and radii of the 4 8 Be nucleus are performed with allowance for all states characterized by the λ=[44] Young diagram, the quantum numbers Kmin and Kmin+2 of the O(3(A?1)) group, and the quantum numbers E=K+2N (N≤9) of the U(3(A?1)) group. The convergence of the results with respect to the extension of the basis is studied, and the structure of relevant wave functions is revealed. The results of these calculations are compared with the results obtained in the analogous approximation of the unitary scheme.  相似文献   

14.
On an example of the D2-line of the Rb atoms the work of the frequency reference of atomic transitions is demonstrated, based on the application of the spectrum of a selective reflectance (SR) from the boundary of atom vapors with the use of nano-cell (NC) with the thickness L ~ λ/2, where λ is the laser wavelength equal to 780 nm. When changing the thickness of the nano-cell near the thickness L ~ λ/2, we observe the inversion of sign of the SR slope profile which is positive when L < λ/2 and negative when L > λ/2. In the case when the incidence angle of the laser beam on the surface of the nano-cell is close to the normal, in real-time it is possible to form the derivative of the SR which represents a resonance peak with ~35 MHz spectral linewidth and located at the atomic transition. The phenomenon of oscillation of the sign of slope while changing the nano-cell thickness from L ~ λ/2 up to L ~ 3/2λ is demonstrated. The practical application of the SR is noted.  相似文献   

15.
The signature splittings in Kπ = 1 +: 7 /2[404] π?9 /2[624] ν, Kπ = 0?: 9 /2[514] π?9 /2[624] ν bands of 180Ta and Kπ = 0?: 7 /2[404] π?7 /2[503] ν, Kπ = 1?: 5 /2[402] π?3 /2[512] ν, Kπ = 1+: 7 /2[404] π?9 /2[624] ν bands of 182Ta are analysed within the framework of two-quasiparticle rotor model. The phase as well as magnitude of the experimentally observed signature splitting in Kπ = 1+ band of 180Ta, which could not be explained in earlier calculations, is successfully reproduced. The conflict regarding placement of a 12 + level in Kπ = 1 +: 7 /2 +[404] π?9 /2 +[624] ν ground-state rotational band of 180Ta is resolved and tentative nature of Kπ = 0?: 7 /2[404] π?7 /2[503] ν, Kπ = 1+: 7 /2[404] π?9 /2[624] ν bands observed in 182Ta is confirmed. As a future prediction for experimentalists, these two-quasiparticle structures observed in 180Ta and 182Ta are extended to higher spins.  相似文献   

16.
The spectral characteristics of the emission of atmospheric-pressure gas-discharge plasma in mixtures of cadmium diiodide vapor with gases (Ne, Ar, Kr, Xe, and N2) were investigated along with the time characteristics of the voltage and current. The gas-discharge plasma was produced and excited by a barrier discharge at a repetition rate of sine voltage pulses of up to 140 kHz. The discharge emission was analyzed in the spectral range 200–900 nm with a high resolution (0.05 nm). Radiation from exciplex CdI(B-X) molecules and excimer I2* molecules was revealed, as well as the atomic lines of cadmium, iodine, and inert gases. In a mixture with xenon, radiation from exciplex molecules XeI(B-X, B-A) was also found. This radiation prevailed in the spectra at mixture temperatures up to 150°C. The further increase of the temperature leads to the prevalence of the CdI(B-X) radiation. It was found that the most intense CdI(B-X) radiation is observed in mixtures CdI2/Xe(N2)/Ne. Regularities in the spectral characteristics of the emission of the gas-discharge plasma are discussed.  相似文献   

17.
Thin films of chalcogenide glasses deposited on quartz glass substrates by thermal evaporation in vacuum have been investigated. The dependences n(λ) and k(λ) for films of different composition have been determined from the transmission spectra. Expressions of the n = A + BL + CL 2 + 2 + 4 type (L = (λ 2 ? 0.028)?1 and A, B, C, D, and E are constants) for calculating the refractive indices of As2Se3, AsSe4, AsS4, and AsS16.2Se16.2 films in the wavelength range from 0.5 to 2.5 μm are reported.  相似文献   

18.
We study the asymptotic structure of the first K largest eigenvalues λ k,V and the corresponding eigenfunctions ψ(?;λ k,V ) of a finite-volume Anderson model (discrete Schrödinger operator) \(\mathcal{H}_{V}= \kappa \Delta_{V}+\xi(\cdot)\) on the multidimensional lattice torus V increasing to the whole of lattice ? ν , provided the distribution function F(?) of i.i.d. potential ξ(?) satisfies condition ?log(1?F(t))=o(t 3) and some additional regularity conditions as t→∞. For zV, denote by λ 0(z) the principal eigenvalue of the “single-peak” Hamiltonian κΔ V +ξ(z)δ z in l 2(V), and let \(\lambda^{0}_{k,V}\) be the kth largest value of the sample λ 0(?) in V. We first show that the eigenvalues λ k,V are asymptotically close to \(\lambda^{0}_{k,V}\). We then prove extremal type limit theorems (i.e., Poisson statistics) for the normalized eigenvalues (λ k,V ?B V )a V , where the normalizing constants a V >0 and B V are chosen the same as in the corresponding limit theorems for \(\lambda^{0}_{k,V}\). The eigenfunction ψ(?;λ k,V ) is shown to be asymptotically completely localized (as V↑?) at the sites z k,V V defined by \(\lambda^{0}(z_{k,V})=\lambda^{0}_{k,V}\). Proofs are based on the finite-rank (in particular, rank one) perturbation arguments for discrete Schrödinger operator when potential peaks are sparse.  相似文献   

19.
The production of charged ρ mesons on nuclei and nucleons is investigated in charged current neutrino interactions at moderate energies (〈E ≈ 10 GeV), using the data obtained with SKAT bubble chamber. No strong nuclear effects are observed in ρ + and ρ ? production. The fractions of charged and neutral pions originating from ρ decays are obtained and compared with higher-energy data. From analysis of the obtained and available data on ρ + and K*+(892) neutrino production, the strangeness suppression factor is extracted: λ s = 0.18 ± 0.03. Estimation is obtained for cross section of coherent ρ + neutrino production on nuclei.  相似文献   

20.
On a fixed Riemann surface (M 0, g 0) with N Euclidean ends and genus g, we show that, under a topological condition, the scattering matrix S V (λ) at frequency λ > 0 for the operator Δ+V determines the potential V if \({V\in C^{1,\alpha}(M_0)\cap e^{-\gamma d(\cdot,z_0)^j}L^\infty(M_0)}\) for all γ > 0 and for some \({j\in\{1,2\}}\) , where d(z, z 0) denotes the distance from z to a fixed point \({z_0\in M_0}\) . The topological condition is given by \({N\geq \max(2g+1,2)}\) for j = 1 and by N ≥ g + 1 if j = 2. In \({\mathbb {R}^2}\) this implies that the operator S V (λ) determines any C 1, α potential V such that \({V(z)=O(e^{-\gamma|z|^2})}\) for all γ > 0.  相似文献   

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