Survival Probability of an Excited Al Atom in the 4s²S_1/2State Sputtered from an Al Surface under Ar⁺Bombardment

Abstract

We describe the asymptotic boundary of the general homogeneous plane wave spacetime, using a construction of the 'points at infinity' from the causal structure of the spacetime as introduced by Geroch, Kronheimer and Penrose. We show that this construction agrees with the conformal boundary obtained by Berenstein and Nastase for the maximally supersymmetric ten-dimensional plane wave. We see in detail how the possibility of going beyond (or around) infinity arises from the structure of light cones. We also discuss the extension of the construction to time-dependent plane wave solutions, focusing on the examples obtained from the Penrose limit of Dp-branes.

Secondary Electron Yield from an Al Surface Bombarded by 20–80 keV Ar+Ions

“…3p 2 P o 3=2 ) increases as a function of oxygen pressure as described in the previous paper 15) and intensity dependence on the projectile current density J is illustrated in Fig. 2.…”

“…1 with details similar to previous work. 15) Briefly, Ar þ ions produced in a duoplasmatron ion source are accelerated from 20 to 80 keV to bombard target surfaces at normal incidence. Beam density is about 0.1 A/m 2 at 40 keV.…”