The transport of excess electrons in liquid argon driven out of equilibrium by an applied electric field is revisited using a multi-term solution of Boltzmann's equation together with ab initio liquid phase cross-sections calculated using the Dirac-Fock scattering equations. The calculation of liquid phase cross-sections extends previous treatments to consider multipole polarisabilities and a n...

The introduction of matrix techniques to the synthesis and study of reactive organic molecules has substantially extended the range of molecules available for investigation (Ref. 1). It is now increasingly the case that we need new chemical methods to make progress in this area of investigation. Diazocompounds and azides have proved especially useful as starting points for a new style of photoc...

We present a cryogenic source of periodic streams of micrometer-sized hydrogen and argon droplets as ideal mass-limited target systems for fundamental intense laser-driven plasma applications. The highly compact design combined with a high temporal and spatial droplet stability makes our injector ideally suited for experiments using state-of-the-art high-power lasers in which a precise synchron...

In a pioneering study, Lee et al. demonstrated how free energies of Lennard-Jones LJ clusters could be determined from Monte Carlo MC simulations. Subsequently, Garcia and Torroja compared the simulation results with both classical nucleation theory and experimental values for argon nucleation. Since then, there have been many such comparisons as well as simulations to determine the properties ...

Supersonic expansion is a very powerful tool to produce an atomic beam with a well defined velocity and, by seeding a test gas in such an expansion, the energy of the test gas can be transferred, at least partially, to the very-low-temperature carrier gas. The case usually studied is the one of a heavy gas seeded in a light carrier gas and, in this case, the parallel temperature of the seeded g...

Despite its apparent simplicity and extensive theoretical investigations, the issue of what is the shape of the helium trimer is still debated in the literature. After reviewing previous conflicting interpretations of computational studies, we introduce the angle-angle distribution function as a tool to discuss in a simple way the shape of any trimer. We compute this function along with many di...

We report on generation of third harmonic from nitrogen molecules on the excited state with a weak driver laser pulse at a mid-infrared wavelength. The excited nitrogen molecules are generated using a circularly polarized intense femtosecond pulse which produces energetic electrons by photoionization to realize collisional excitation of nitrogen molecules. Furthermore, since the third harmonic ...

We outline a new kinetic theory for positrons in soft matter, which blends together cross sections for positrons scattering from single molecules, with the structure function of the medium as a whole. Numerical results are presented for positrons in liquid argon, where negative differential conductivity arises from both positron formation and the structure of the medium.