Related papers: Magic Numbers for Packing Adamantane in Helium Dro…
The effects of interactions between He- and clusters of fullerenes in helium nanodroplets are described. Electron transfer from $He^{-}$ to $(C_{60})_n$ and $(C_{70})_n$ clusters results in the formation of the corresponding fullerene…
We have studied complexes of gold atoms and imidazole (C$_3$N$_2$H$_4$, abbreviated Im) produced in helium nanodroplets. Following the ionization of the doped droplets we detect a broad range of different Au$_m$Im$_n^+$ complexes, however…
Dissociation and fission of small neutral, singly and doubly charged strontium clusters are studied by means of ab initio density functional theory methods and high-resolution time-of-flight mass spectrometry. Magic numbers for small…
We review the theory behind abundance of experimentally observed nanoclusters produced in beams, aiming to understand their magic number behavior. It is shown how use of statistical physics, with certain assumptions, reduces the calculation…
The distribution of the sizes of clusters is not continuous, but rather has local maxima. The numbers of atoms of those maxima distribution is called magic numbers. Two methods of determining magic numbers are firstly introduced, followed…
We present the results of over 90 tight-binding molecular-dynamics simulations of collisions between three- and five-atom silicon clusters, at a system temperature of 2000K. Much the most likely products are found to be two 'magic'…
We use a novel technique to solvate silver cations in small clusters of noble gases. The technique involves formation of large, superfluid helium nanodroplets that are subsequently electron ionized, mass-selected by deflection in an…
We study superfluid helium droplets multiply charged with ions. When stable, the charges are found to reside in equilibrium close to the droplet surface, thus representing a physical realization of Thomson's model. We find the minimum…
Electron ionization of helium droplets doped with cesium or potassium results in doubly and, for cesium, triply charged cluster ions. The smallest observable doubly charged clusters are $Cs_{9}^{2+}$ and $K_{11}^{2+}$; they are a factor two…
Electron-induced chemistry in imidazole (IMI) clusters embedded in helium nanodroplets (with an average size of 2$\times$10$^5$ He atoms) has been investigated with high-resoluton time-of-flight mass spectrometry. The formation of both,…
Variational MonteCarlo and Diffusion MonteCarlo calculations have been carried out for cations like Li$^+$, Na$^+$ and K$^+$ as dopants of small helium clusters over a range of cluster sizes up to about 12 solvent atoms. The interaction has…
We present a new approach to understanding star-to-star helium abundance variations within globular clusters. We begin with detailed radiation hydrodynamics simulations of cluster formation within giant molecular clouds, and investigate the…
Anions are formed by electron attachment to helium nanodroplets doped with N$_2$. The most prominent ion series is due to odd-numbered N$_m$$^{-}$ with 3 $\le$ m < 140. Neither N$^{-}$ nor N$_2$$^{-}$ are observed. An appearance energy of…
We show that element diffusion can produce large fluctuations in the initial helium abundance of the star-forming clouds. Diffusion time-scale, which in stars is much larger than the Hubble time, can fall below 10^8 years in the neutral gas…
We propose that the abundance anomalies of proton-capture elements in globular clusters, such as the C-N, Na-O, Mg-Al and Na-F anti-correlations, were produced by super-massive stars with M ~ 10,000 Msun. Such stars could form in the…
We use high-resolution three-dimensional adaptive mesh refinement simulations to investigate the interaction of high-redshift galaxy outflows with low-mass virialized clouds of primordial composition. While atomic cooling allows star…
We report on the production and study of stable, highly charged droplets of superfluid helium. Using a novel experimental setup we produce neutral beams of liquid helium nanodroplets containing millions of atoms or more that can be ionized…
The abundances of elements in stars are a critical clue to their origins. Observed star-to-star variations in logarithmic abundance within an open cluster are typically only $\sim 0.01-0.05$ over many elements, significantly smaller than…
The reactions of carbon atoms with dihydrogen have been investigated in liquid helium droplets at $T$ = 0.37 K. A calorimetric technique was applied to monitor the energy released in the reaction. The barrierless reaction between a single…
Helium abundances and atmospheric parameters have been determined from high resolution spectra for a new sample of 46 bright hot subdwarf B (sdB) stars. The helium abundances have been measured with high accuracy. We confirm the correlation…