We measured the electron capture to the continuum (ECC) peak in the ionization of He atoms by the collision of 50, 100 and 200 keV H+ and 100 keV amu-1 He2+. We exhaustively scanned the double differential cross section between the angles -1.5 degrees to 10 degrees and within the velocities (1+or-0.15) upsilon i where upsilon i is the impact velocity. We propose a new method for analysing the ECC structure which is independent of the spectrometer transmission function modellization and enables a direct comparison with the available theories. Furthermore, we distinguish two regimes for the ionization process, depending on whether the electron velocity is larger or smaller than the projectile velocity.

The Raman spectra of a number of the colossal magnetoresistance manganites and related systems are shown to display strong broad vibrational bands in both first and second order. The modes derive from the entire phonon branch involving the vibration of the oxygen ions in the MnO 2 planes, ions which participate in Jahn-Teller displacements. The strength and temperature dependence of the second-order signal are shown to follow from conventional resonance scattering; they do not support the model that invokes Frank-Condon scattering.

We study the classical distribution of particles in a collision process. This is the classical analogue to the square modulus of the quantum mechanical stationary continuum wavefunction. We evaluate this distribution in coordinate and momentum space analytically, comparing its similarities and discrepancies with the corresponding quantum mechanical particle density.

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Articles you may be interested inTotal cross section exceeds transport cross section for quantum scattering from hard bodies at low and high wave numbers Super classical quantum mechanics: The best interpretation of nonrelativistic quantum mechanics Am.We discuss an alternative classical description of the nonrelativistic scattering process that is completely analogous to the time-independent formalism employed in quantum-mechanics textbooks. This approach provides an elementary introduction to the standard stationary scattering theory, embodying many of its essential concepts. ©

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