On the Deser,Gilbert, Sudarshan representation for functions Wi(ν, q2)(i = 1, 2) describing the electroproduction process

The Deser, Gilbert, Sudarshan representation (D.G.S.R.) for the functions W_i(ν, q²) (i = 1,2) is considered as equations determining spectral functions h_i(a, α) via the values W_i(ν, q²) in the physical region of the electroproduction channel. It is shown that if W_i(ν, q²) obey the microcausality and spectrality conditions, then the equations for h_i(a, α) have solutions in the class of Schwartz temperated distributions and thereby the D.G.S.R. is proved. Formulae are obtained expressing spectral functions in the D.G.S.R. through the values of functions W_i(ν, q²) in the physical region of the electroproduction channel.     

Infrared and laser Raman gas spectra of SnH4

In the present work the ν₃(f₂) Raman band and the 2ν₃ infrared band of SnH₄ are reported. Analyses have been performed for the ν₃(f₂) Raman band and the ν₂(e), ν₃(f₂), ν₄(f₂) and 2ν₃ infrared bands. The interatomic distance in the ground state has been found to be 1.7108 ± 0.0010 Å.     

Infrared and laser Raman gas spectra of SiH4 and SiD4

The ν₂(e) and ν₃(f₂) Raman spectra have been examined. For ²⁸SiH₄ the ν₂(e) and ν₄(f₂) infrared bands are partly analyzed and compared with a computed band-contour; the ν₁ + ν₃ combination infrared band has been presented. For ²⁸SiH₄ the 2ν₃ overtone infrared band has been observed and analyzed. The new data are combined with those of the ν₃(f₂) infrared bands to derive an improved set of rovibrational constants of ²⁸SiH₄ and ²⁸SiD₄. The analyses yield $\text{r}{}_0\text{= 1.4806 ± 0.0008}\text{A}\text{?}$ for ²⁸SiH₄ and $\text{r}{}_0\text{= 1.4784 ± 0.0006}\text{A}\text{?}$ for ²⁸SiD₄ in agreement with the Laurie-Herschbach theorem.     

Infrared and laser Raman gas spectra of GeD4

The ν₂(e) and ν₃(f₂) Raman spectra and the 2ν₃ infrared spectrum of gaseous GeD₄ have been observed and analyzed. The new data have been combined with those of the ν₃(f₂) infrared band to derive an improved set of rovibrational constants. The analysis yields B₀ = 1.3544 ± 0.0010 cm^?1 and $\text{r}{}_0\text{= 1.5223 ± 0.0006}\text{A}\text{?}$.     

Frequency dependence of the freezing temperature in spin glasses: A comparative study of (La,Gd)B6, (Y,Gd)Al2 and (La,Gd)Al2

The frequency dependence of the freezing temperatureT _f(ν) is determined for the dilute spin glass systems (La, Gd)B₆ and (Y, Gd)Al₂ in the frequency range 10–1,000 Hz. While for (La, Gd)B₆,T _f(ν) is found to be weak, for (Y, Gd)Al₂ T _f(ν) is even stronger than for the previously studied system (La, Gd)Al₂. Both, measurements of the temperature dependence of the susceptibility nearT _f and calculations of the RKKY pair interaction, suggest that this difference is correlated with a different sign of the nearest-neighbor interaction, which appears to be antiferromagnetic for (La, Gd)B₆ and ferromagnetic for (Y, Gd)Al₂ as well as (La, Gd)Al₂.     

Radiofrequency spectroscopy of DCCD: Deuterium quadrupole coupling in acetylene

Molecular beam electric resonance spectroscopy has been used to observe the P(16)e and P(16)f transitions in the ν₅-ν₄ band of dideutero acetylene. Hyperfine transitions were resolved in the P(16)e case, providing deuterium quadrupole coupling and spin rotation information. The hyperfine properties are essentially the same for ν₄, J = 16 and ν₅, J = 15 with eQq = 209(1) kHz and C = −0.42(2) kHz. This information is compared with other measurements of deuterium quadrupole coupling in acetylene.     

Zerfallende Zustände als physikalisch nichtisolierbare Teilsysteme

Presently the investigations of decaying quantum mechanical systems lack a well-founded concept, which is reflected by several formal difficulties of the corresponding mathematical treatment. In order to clarify in some respect the situation, we investigate, within the framework of nonrelativistic quantum mechanics, the resonant scattering of an initially well localized partial wave packet ϕ_l(r, t). If the potential decreases sufficiently fast for r → ∞, ϕ_l(r, t) can be expressed at sufficiently long time after the scattering has taken place, as ϕ_l(r, t) = I(r, t) + ∑ N_iϕl(K_i, r) exp {–iK_i² t/2M} × Θ(k_i – γ_i – Mr/t), ϕ_l(K_i, r) being the resonant solution with complex “momentum” K_i = k_i – iγ_i. From this heuristic relation one can deduce not only the probability for the creation of unstable particles but also obtain some hints to a connection between decaying states and physically nonisolable partial systems. On the other hand, this connection can perhaps display the inadequacy of attempts which suggest to solve the problem of decaying states within the usual Hilbert space methods.     

Dynamics of the infinite-range ising spin glass

The Glauber dynamics of an Ising spin glass with infinite-range interactions and additional static field, h, is investigated near the freezing temperature, T_f. We obtain critical slowing down at and below the de Almeida-Thouless instability line, h_c(T), to order (1?T/T_f)³ with algebraic decay of the spin correlations ～t^?ν, where $\text{ν=}\text{1}\text{2}$ at T_f and $\text{ν≤}\text{1}\text{2}$ for T<T_f.     

Special analytic properties of the amplitude for scattering on the Woods-Saxon potential

It is shown that the s-wave partial amplitude f(k) for scattering on the real-valued Woods-Saxon potential V(r)=?V ₀/[1+exp((r?R)/d)] has very special analytic properties: the trajectories of the poles of the function k cotδ [of the zeros of the amplitude f(k)] coincide with the lines of the dynamical singularities [spurious poles of f(k)], so that the zeros and the poles compensate each other. In contrast to what is obtained for Yukawa-like potentials, the scattering length does not vanish here at zero energy. The results reported in this article were obtained analytically under the assumption that exp(-R/d)?1. The problem of revealing the poles of the function k cotδ in a partial-wave analysis of neutron scattering on nuclei is discussed.     

High spin shell model excitations in149Gd

The high spin level structure of the three-neutron nucleus¹⁴⁹Gd has been investigated by in-beamγ-ray and electron spectroscopy with (α, xn) reactions. The observed levels are characterized as members of the shell model multipletsνf ₇ ^2/3 ,νh _9/2 f ₇ ^2/2 ,νf ₇ ^2/3 ×3^?,νh _9/2 f ₇ ^2/2 ×3^?, and tentativelyνf ₇ ^2/3 ×(3^?)². The energies of theν f ₇ ^2/3 states agree only moderately with those calculated using empirical two-nucleon interactions taken from¹⁴⁸Gd, which indicates the importance of long range contributions already atN=85.     

The 250 nm absorption spectrum of benzene: Vibronic analysis

The supporting details for assignment of band maxima (see paper I) in the one-photon ${}^1\text{B}{}_{\mathrm{2u}}\text{←}{}^1\text{A}{}_{\mathrm{1g}}$ absorption spectra of benzene vapor are given. By the criteria of band separations and Franck-Condon intensities, maxima are first sorted into ν₁ progressions (Table II). The progressions are then assigned by systematic search for allowed first-, second-, and third-order Herzberg-Teller transitions as set forth in Table II of Paper II. Much attention is given to vibrational angular momentum as it affects band contours and component splittings. Over 90% of the intensity is assigned and a consistent pattern of Herzberg-Teller activity is found. Both the list of modes observed to be active in vibronically inducing the transition (ν₄, ν₅, ν₆, ν₇, ν₉, ν₁₀, ν₁₁, ν₁₆, ν₁₇) and the relative intensities of various types of transitions found in absorption match well that seen in SVL fluorescence. Third-order transitions are comparatively few in number, but are equivalent in intensity to many second-order transitions. Variation in the separation between progression members suggests that small (and unidentified) perturbations of upper state vibronic levels are ubiquitous. Revised or new values of nine fundamentals in the ¹B_2u state and two in the ¹A_1g state are given (Table IV). Some of the excited and ground state anharmonic constants x_i⁰, x_i,i⁰, x_i,j⁰, g_i,i, and g_i,j are deduced for ν₅, ν₆, ν₁₀, ν₁₁, ν₁₆, and ν₁₇ (Table V).     

Interaction between a He atom and a graphite surface

A study is presented of the interaction V(r) between a He atom and a graphite surface. V(r) is assumed equal to a sum of pair interactions U(r ? R_i) between the He and C atoms. None of a set of isotropic potentials (dependent only on the magnitude ¦r ? R_i¦) is consistent with recent scattering data. Anisotropie pair potentials, in contrast, are found to yield good agreement. The origin of this anisotropy is analyzed in terms of the graphite dielectric function and charge density.     

Observation of new nuclides37Si,40P,41S,42S produced in deeply inelastic reactions induced by40Ar on238U

A non-relativistic quantum-mechanical system is studied which consists ofN identical bosons interacting by pair potentials of the form 〈r¦V¦r ¹〉=?π/2ν ₀ a ^?3 f(r/a)f ^*(r ¹/a). General upper and lower bounds to the ground-state energyE _N are provided for alla, V ₀ andN, and detailed results are given in the case of the Yamaguchi potential for whichf(x)=e ^?x/x. It is shown that the ratioE _N /E ₂ diverges both under the limit (i) a↓0,E ₂ =arbitrary constant <0, and (ii) (V ₀ a ²)↓(V ₀ a ²)_c, where (V ₀ a ²) _c corresponds toE ₂=0. The results complement recent studies of the Efimov effect via scattering theory.     

Predictions for inclusive reactions based on a parton structure of hadrons

It is proposed that the asymptotic single-particle distributions f(x)=x(dσ/dx) in inclusive reactions should reflect the limiting longitudinal momentum distribution, ∼νW₂(x), of the hypothetical partons constituting a hadron. It is further argued that f(x) becomes, proportional to νW₂(x) as x → 1. Predictions are then made for a large class of inclusive reactions based on our knowledge of νW₂(x) from electroproduction data. For some of these (such as pp → π^±X), in which the predictions differ markedly from the Regge ones, present experiments distinctly favor ours.     

Vector correlations in the F + HD reaction

A theoretical study of the orientation of product rotational angular momenta for two chemical reaction channels: F + HD(ν _r = 0, j _r = 0) → HF(ν, j) + D and F + HD(ν _r = 0, j _r = 0) → DF(ν, j) + H at a E _coll = 78.54 meV collision energy was performed. Angular momentum orientation was described on the basis of irreducible tensor operators (state multipoles) expressed through anisotropy transfer coefficients, which contained quantum-mechanical scattering T matrices determined on the basis of exact solutions to quantum scattering equations obtained using the hyperquantization algorithm. The possibility of the existence of substantial orientation of the angular momentum of reaction products j in the direction perpendicular to the scattering plane was demonstrated. The dependences of differential reaction cross sections and state multi-poles on the ν and j quantum numbers were calculated and analyzed. A experimental scheme based on the multiphoton ionization method was suggested. The scheme can be used to detect predicted reaction product angular momentum orientation.     

The methane ν1(a1) vibrational state rotational structure obtained from high-resolution CARS-spectra of the Q-branch

The gaseous methane ν₁(a₁), Q-branch coherent anti-Stokes Raman scattering (CARS) spectra have been investigated at a resolution of 0.002 cm^?1. A complex rotational structure of the resolved Q-branch has been experimentally observed. This structure can be ascribed to strong tetrahedral splitting of the rotational levels of the upper vibrational state, which possibly occurs due to Fermi resonance between the ν₁(a₁) and 2ν₂(a₁) vibrational energy levels which are close to each other. An assignment of the observed spectral lines has been made, yielding the rotational constants B, D, and D_t for the ν₁(a₁) vibrational state of the methane molecule. The absolute Raman frequency ν₁ of the purely vibrational transition has been found.     

Solving the linearized Φ4 equation in external driving fields

The Φ⁴ equation, linearized about a kink at rest, is solved for external driving fields F(t) = Σ_i=n^∞f_itⁱ. The x-dependent part of the solution $\text{u}\text{?}\text{(x, t)}$ is proportional to the translation mode. This implies that also for large times the kink's dynamics is adiabatic, if the external field is sufficiently weak and $\text{|}\text{u}\text{?}\text{|? z1}$|ν| ? 1.     

Measurement of weak meson form factors in spacelike regions

With the construction of high energy, high intensity accelerators (NAL & CERN, SPS) investigation of neutrino scattering on virtual pions, á la Chew-Low, becomes experimentally possible. We propose to analyse the process ν + N → μ^? + K + Δ to extract the usual K_?3 form factor(s) for spacelike momentum transfer. A model calculation suggests that f₊(T) can be determined reasonably well from a triple differential cross section, whereas only rough information on f_?(T) may be obtained from the transverse polarization of the muon. The experiment proposed requires scanning of several millions of bubble chamber pictures.