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We report on the measurement of the ^{7}Be(n,p)^{7}Li cross section from thermal to approximately 325 keV neutron energy, performed in the high-flux experimental area (EAR2) of the n_TOF facility at CERN. This reaction plays a key role in the lithium yield of the big bang nucleosynthesis (BBN) for standard cosmology. The only two previous time-of-flight measurements performed on this reaction did not cover the energy window of interest for BBN, and they showed a large discrepancy between each other. The measurement was performed with a Si telescope and a high-purity sample produced by implantation of a ^{7}Be ion beam at the ISOLDE facility at CERN. While a significantly higher cross section is found at low energy, relative to current evaluations, in the region of BBN interest, the present results are consistent with the values inferred from the time-reversal ^{7}Li(p,n)^{7}Be reaction, thus yielding only a relatively minor improvement on the so-called cosmological lithium problem. The relevance of these results on the near-threshold neutron production in the p+^{7}Li reaction is also discussed.

Photoneutron cross sections were measured for 94 Mo, 95 Mo, 96 Mo, 97 Mo, 98 Mo, and 100 Mo near the neutron threshold with quasi-monochromatic laser-Compton scattering γ rays. The photoneutron data were analyzed with the Skyrme Hartree-Fock-Bogoliubov (HFB) plus quasiparticle random phase approximation (QRPA) model and the axially symmetric-deformed Gogny HFB plus QRPA model of E1 γ -ray strength. Combining the γ -ray strength function constrained by the present photoneutron data with either the nuclear resonance fluorescence data or the updated Oslo data to supplement the data below the neutron threshold, a thorough analysis of the reverse (n,γ ) cross sections is made whenever measurements are available. The Oslo data and the corresponding uncertainties are updated based on the latest results of the s-wave neutron spacing and the average radiative width determined in particular for 96 Mo. Finally, radiative neutron capture cross sections for two radioactive nuclei, 93 Mo and 99 Mo, are deduced with the γ -ray strength function method.

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We detected parent and fragment ions from 14 chlorinated and a few fluorinated compounds as well as dibenzo-p-dioxin (dioxin) in intense laser fields. The irradiation pulse had an intensity from 1 × 1013 to 1 × 1015 W cm-2, with a 130-fs pulse duration at a central wavelength of 800 nm. Irradiation at this intensity led to a singly ionized species and a small amount of atomic ions, indicating the onset of Coulomb explosions. We have previously reported finding a key factor in determining the parent and/or fragment ion formations of organic hydrocarbons with an intense femtosecond laser pulse [Harada, H.; et al. Chem. Phys. Lett. 2001, 342, 563−570]. This key factor is a requirement for parent ion predominance if the excitation laser wavelength and the absorption spectra of the target cation are in nonresonance, and vice versa. Use of this factor has been found to be effective for molecules other than hexachlorobutadiene. The threshold intensities I sat at the infinity ionization rate were determined and are reasonably comparable to those of previously reported hydrocarbons.