Branching ratios between correlated and uncorrelated two electron transitions into the K-shell of Al,Ca, Fe and Ni ions

The branching ratios between the radiative single and double electron transitions into the doubly ionized K-shell were measured as a function of the atomic number. The results are compared with various theoretical predictions.     

Surface diffusion of potassium on theW (112) plane

Dependent on temperature and coverage, numerous spectral density functionsW(f) of the field-emission flicker noise of potassium adsorbed on the tungsten (112) plane were determined. The analysis in terms of the Timm and van der Ziel model gives surface diffusion energies between 0.55 and 0.83 eV for (average) coverages from 0.3 to 1.0 and diffusion coefficients between 2×10^–10 and 3×10^–9 cm²/s at 400 K. The results are compared with those obtained previously for the tungsten (111) region. Some conclusions as to the mechanism of diffusion and the manifestation of phase transitions between commensurate and incommensurate adlayer structures are discussed.On leave from Wrocaw University     

Multiplet structure of P-excitons in CuBr due to valence band degeneracy

The two-photon absorption spectrum of CuBr shows a fourfold energy splitting of the 2P- and 3P-excitons of the Z_1,2 series. The splitting results from d-like contributions to the kinetic energy of the hole (Γ_δ) which lead to a coupling between angular momentum and hole spin. The energy splitting allows to determine the spherical and cubic parameters μ and δ of the reduced exciton mass. The results are compared with corresponding values of an existing band structure calculation.     

Evidence for a molecular REC-effect in heavy ion collisions

Anisotropy spectra of the MOK X-ray transitions have been measured in F-Al, Al-Al and Cl-Al collisions as a function of the projectile energy. The measurements at higher energies indicate a new molecular effect due to transitions from quasicontinuum states to the MO 1s _σ-orbitals.     

Emission of neutrino pairs by an electron in an ultrastrong magnetic field

The transitions of relativistic electrons in a magnetic field with the emission of an antineutrino-neutrino pair are considered. Probabilities are obtained for electron transitions to the ground state and weakly excited states. It is shown that in the case of an ultrastrong magnetic field (HH_o=m²c³/e=4.41·10¹³ G) such transitions made a considerable contribution to the total probability of the process.Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 3, pp. 110–114, March, 1978.In conclusion, the authors express their profound gratitude to A. A. Sokolov for his attention to our work.     

X-ray emission from a laser irradiated target in the presence of high electric field

The temporal characteristics of the X-ray emission from a laser irradiated Ai target in a 20 kV/cm electric field are measured with electronic detectors. Spatial and spectral distributions of the X-ray radiation are evaluated using a pinhole camera and filter technique.     

Magnetization processes of CuMn below the freezing temperature Tf

A simple classical model [5] that is based on a blocking of magnetic clusters in a uniaxial anisotropy field explains characteristic properties of magnetization processes of Cu(5–15 at.%) Mn as transition states between the “zero point magnetization” M₀ = M(T → OK) and the thermal equilibrium magnetization M_∞ = M(t → ∞, T). Further it shows two facts the experimental confirmations of which we report in this paper: (a) a magnetization decrease with increasing temperature in high fields and (b) a superposition rule for the magnetization processes in small fields and at low temperatures.     

Molecular-orbital X-rays from 1 GeV 208Pb + 208Pb and 209Bi + 209Bi collisions

We have measured the spectra of continuum X-rays above the characteristic K lines for 4.5 to 4.8 MeV/N ²⁰⁸₈₂Pb → ²⁰⁸₈₂Pb, Pb → Bi, Bi → Pb and Bi → Bi collisions. Above ≈400 keV X-ray energy the spectral shape and intensity agree roughly with calculations of Kirsch et al. for the 1sσ molecular-orbital (MO) X-ray spectrum from Pb-Pb. Deviations from the theory below ≈400 keV suggest transitions to other MO's.     

Laser spectroscopy of ethylene with waveguide CO2 and N2O lasers

Fifty Doppler-broadened absorption lines of ethylene have been measured within large profiles CO₂ or N₂O lase lines. These laser lines are produced by a high pressure waveguide laser and have a full width between 200 and 900 MHz. Eleven absorption lines, the more intense ones, have been assigned to the ν₇ band of C₂H₄. The other absorption lines must belong to hot bands or to the ν₇ band of H₂¹²C¹³CH₂.