Multi-µJ coherent extreme ultraviolet source generated from carbon using the plasma harmonic method.
We demonstrate intense high-order harmonic generation from plasma that is created from different carbon targets. We obtain high-order harmonic energy in the multi-microjoule range for each harmonic order from the 11th to the 17th harmonic. By analyzing the target morphology and the plasma composition, we conclude that the intense harmonics from the bulk carbon targets originate from nanoparticles target.
Photoionization of the fullerene ion C+60
The photoionization cross section of the fullerene ion C+60 has been calculated within a single-electron approximation and also by using a consistent many-body theory accounting for many-electron correlations. Electronic wavefunctions of the ground and excited states have been determined within the jellium model based on the local density approximation. A giant resonance in the photoionization cross section at the photon energy ∼25 eV is predicted. It is demonstrated that the resonance profile is much higher and narrower than in the case of the neutral fullerene C60.
5.63 and 5.80 MeV levels of Ne20; de-excitation branching
Abstract The ratio Г γ /Г for the 5.63 and 5.80 MeV levels of Ne 20 has been determined to be 0.077 (±0.008) and −4 , respectively, by using the C 12 (C 12 , α)Ne 20 reaction and determining the fraction of the events in which the alpha-particle and the Ne 20 recoil are present in coincidence at the kinematically correct angles. In both cases these results in themselves are shown to imply radiative E1 transition (5.63→1.63 and 5.80→0, respectively) probabilities ⪡5 × 10 −5 Weisskopf units. When taken together with the life-time for the 5.63 MeV level measured by Evans et al . values of Г( E1 ) ≲ 5 × 10 −6 and Г α ≈ 6% of the particle estimate are obtained for this state.