Related papers: Excitations in confined helium
Using a quantum-mechanical close-coupling method, we calculate cross sections for fine structure excitation and relaxation of Si and S atoms in collisions with atomic hydrogen. Rate coefficients are calculated over a range of temperatures…
We report on microscopic calculations for the 4He compound system in the framework of the resonating group model employing realistic nucleon-nucleon and three nucleon forces. The resulting scattering phase shifts are compared to those of a…
Molecules immersed in liquid helium are excellent probes of superfluidity. Their electronic, vibrational and rotational dynamics provide valuable clues about the superfluid at the nanoscale. Here we report on the experimental study of the…
Structure and superfluid response of nanoscale size helium-four clusters enclosed in spherical cavities are studied by computer simulations. The curved surface causes the formation of well-defined concentric shells, thus imparting to the…
The series of calculations of differential cross sections and analyzing powers (Ay) of the elastic proton scattering on isotopes 6He and 8He was presented in the framework of the theory of Glauber multiple diffraction scattering. The…
A multi-cell He gas-scintillator active target, designed for the measurement of photoreaction cross sections, is described. The target has four main chambers, giving an overall thickness of 0.103 $\mathrm{g/cm^{2}}$ at an operating pressure…
We present incoherent quasi-elastic neutron scattering measurements in a wavevector transfer range from 0.4 AA^{-1} to 1.6AA^{-1} on liquid n-hexane confined in cylindrical, parallel-aligned nanochannels of 6 nm mean diameter and 260…
A phenomenological optical potential is generalized to include the Coulomb and nuclear interactions caused by the dynamical deformation of its surface. In the high-energy approach analytical expressions for elastic and inelastic scattering…
The properties of ripplonic polarons in a multielectron bubble in liquid helium are investigated on the basis of a path-integral variational method. We find that the two-dimensional electron gas can form deep dimples in the helium surface,…
In the framework of the double folding model, we used the {\alpha}+2n and di-triton configurations for the nuclear matter density of the 6He nucleus to generate the real part of the optical potential for the system 6He+12C. As an…
Electrons on liquid helium can form different phases depending on density, and temperature. Also the electron-ripplon coupling strength influences the phase diagram, through the formation of so-called "ripplonic polarons", that change how…
The elastic scattering of the halo nucleus $^6$He from heavy targets at incident energies near the Coulomb barrier displays a marked deviation from the standard Fresnel-type diffraction behavior. This deviation is due to the strong Coulomb…
It is shown that the drastic distinction in the rotational structure of molecules in the He4 and He3 liquids observed in [1] is due to the difference in the spectral density of excitations regardless of the hydrodynamic properties. The…
The calculation of the differential cross section of the inelastic p9Be scattering (to the levels J = 1/2, 3/2) was made in the framework of the Glauber diffraction theory. We used the wave function of 9Be in the ground and excited states…
A few atomic layers of helium adsorbed on graphite have been attracting much attention as one of the ideal quantum systems in two dimension. Although previous reports on neutron diffraction have shown fundamental structural information in…
We study the scattering of atoms, rotons and phonons at the free surface of $^4$He at normal incidence and calculate the evaporation, condensation and reflection probabilities. Assuming elastic one-to-one processes and using general…
Motivated by the needs of atomic tritium sources for neutrino mass experiments and Doppler-free two-photon 1S-2S spectroscopy in atomic deuterium and tritium, we present calculations of energy-dependent elastic scattering cross sections of…
A microscopic calculation of reaction cross sections for nucleon-nucleus scattering has been performed by explicitly coupling the elastic channel to all particle-hole excitations in the target and one-nucleon pickup channels. The…
The scattering of atoms and rotons at the free surface of superfluid 4He is studied in the framework of linearised time dependent mean field theory. The phenomenological Orsay-Trento density functional is used to solve numerically the…
We provide a theoretical explanation for the optical modes observed in inelastic neutron scattering (INS) on the bcc solid phase of helium 4 [T. Markovich, E. Polturak, J. Bossy, and E. Farhi, Phys. Rev. Lett. 88, 195301 (2002)]. We argue…