Optical absorption in boron clusters B6_{6} and B6+_{6}^{+} : A first principles configuration interaction approach

The linear optical absorption spectra in neutral boron cluster B$_{6}$ and cationic B$_{6}^{+}$ are calculated using a first principles correlated electron approach. The geometries of several low-lying isomers of these clusters were optimized at the coupled-cluster singles doubles (CCSD) level of theory. With these optimized ground-state geometries, excited states of different isomers were computed using the singles configuration-interaction (SCI) approach. The many body wavefunctions of various excited states have been analysed and the nature of optical excitation involved are found to be of collective, plasmonic type.Comment: 22 pages, 38 figures. An invited article submitted to European Physical Journal D. This work was presented in the International Symposium on Small Particles and Inorganic Clusters - XVI, held in Leuven, Belgiu

Measurements of the Branching Fractions of Exclusive Charmless B Meson Decays with Eta-prime and Omega Mesons

We present the results of searches for B decays to charmless two-body final states containing η′ or ω mesons, based on 20.7fb-1 of data collected with the BABAR detector. We find the branching fractions B(B+→η′K+) = (70±8±5)×10-6, B(B0→η′K0) = (42-11+13±4)×10-6, and B(B+→ωπ+) = (6.6-1.8+2.1±0.7)×10-6, where the first error quoted is statistical and the second is systematic. We give measurements of four additional modes for which the 90% confidence level upper limits are B(B+→η′π+)<12×10-6, B(B+→ωK+)<4×10-6, B(B0→ωK0)<13×10-6, and B(B0→ωπ0)<3×10-6