Phenomenological analysis of the decay $$B^{\pm }\rightarrow K^{\pm } p {\bar{p}}$$ B ± → K ± p p ¯

Abstract

We propose a parametrization for interpreting some of the presently available data of the B ± → K ± pp decay, in particular those by the LHCb and Belle Collaborations. The model is inspired by the well-known current and transition contributions, usually assumed in this kind of decay. However, in the light of considerations as regards the dominant diagrams and final state interactions, we modify some parameters of the model, determining them by means of a best fit to the data. We show the results, which we discuss in some detail. Moreover, we give some predictions on other observables relative to the decays.

Au nanocluster growth on Graphene supported on Ni(111)

“…The surface sensitivity enabled by shadowing and blocking depends on the crystal structure and the ion incidence and exit directions. In previous work, a detailed analysis was used to show that low energy Na + singly scattered from PVD-grown Au nanoclusters probes only the outermost Au atoms in the clusters [18]. including the background, which assumes that the error is purely statistical.…”

“…Ref. [18]. In brief, as an ion approaches a surface, the ionization level sees its image charge and shifts up in energy, while at the same time the level broadens by hybridizing with states in the solid [54,55].…”

“…LEIS employing 3.0 keV Na + projectiles shows that the deposited Au atoms do form nanoclusters on Gr/Ni(111). The neutralization probability as a function of the amount of deposited Au decreases with coverage, which is an indication that the atoms at the periphery of the clusters are positively charged [18]. In addition, oxygen is intercalated to increase the spacing between the Gr and Ni and decouple the film from the substrate [47], but no changes in the growth mode or the Na + neutralization probability are observed.…”

“…The adsorption of precursors and the subsequent catalytic reactions are generally considered to occur at the edges of the clusters [13][14][15][16][17]. In addition, density functional theory (DFT) has shown that the periphery atoms of Au clusters on oxide supports are positively charged while the center atoms are nearly neutral [13,14,18]. It has been proposed that oxygen in the substrate forms strong chemical bonds to the clusters that leads to charge transfer away from the edge atoms, and that this bonding is what produces the catalytically active sites on the nanoclusters [1,19].…”

“…A novel form of alkali low energy ion scattering (LEIS) [44,45] is used here to probe Au nanoclusters deposited by PVD onto Gr films on Ni(111). LEIS is extremely surface sensitive [46] and able to monitor the growth mode and average charge state of the Au atoms in the nanoclusters [18]. LEIS employing 3.0 keV Na + projectiles shows that the deposited Au atoms do form nanoclusters on Gr/Ni(111).…”