Photoionization of highly charged ions using an ECR ion source and undulator radiation

Photoionization of Xe4+ to Xe7+ ions was studied by combining an electron cyclotron resonance ion source with synchrotron radiation. Multiconfiguration Dirac-Fock calculations were performed to interpret the data. Many autoionization lines were measured and identified, resulting from excitation of a 4d electron into nf and np orbitals followed by Auger decay of the excited states. Continuum photoionization is negligible for the higher members of the isonuclear series.     

Classical and statistical analysis of40Ar(300 MeV)+197Au deep inelastic interaction

We examine the way in which local field effects in the neutron refractive index affect the values of coherent scattering lengths determined by various kinds of neutron optical measurements. We find that under typical experimental conditions these effects are negligible for interferometry measurements but that they are significant for gravity refractometry measurements, producing changes in the effective scattering length of as much as two or three standard deviations in some cases. Refined values of the scattering lengths are obtained for the thirteen elements for which data are presently available. The special role of local field effects in neutron transmission is also discussed.     

Small exponent asymptotics

We study the surprisingly complicated asymptotic character ofa simple first-order differential equation, which involves aterm with a low exponent of the dependent variable. While numericalsolutions and straightforward asymptotic expansions indicatea clearly defined boundary layer type transition, we find thatthe correct asymptotic structure involves a 'hidden' boundarylayer, and that a straightforward approach cannot discern this.