title: Granular gases of rod-shaped grains in microgravity.
abstract: Granular gases are convenient model systems to investigate the statistical physics of nonequilibrium systems. In the literature, one finds numerous theoretical predictions, but only few experiments. We study a weakly excited dilute gas of rods, confined in a cuboid container in microgravity during a suborbital rocket flight. With respect to a gas of spherical grains at comparable filling fraction, the mean free path is considerably reduced. This guarantees a dominance of grain-grain collisions over grain-wall collisions. No clustering was observed, unlike in similar experiments with spherical grains. Rod positions and orientations were determined and tracked. Translational and rotational velocity distributions are non-Gaussian. Equipartition of kinetic energy between translations and rotations is violated.
authors.affiliation: Institute of Experimental Physics, Otto-von-Guericke Universität Magdeburg, D-39016 Magdeburg, Germany.
authors.forename: K
authors.initials: K
authors.lastname: Harth
authors.affiliation: Institute of Experimental Physics, Otto-von-Guericke Universität Magdeburg, D-39016 Magdeburg, Germany.
authors.forename: U
authors.initials: U
authors.lastname: Kornek
authors.affiliation: Institute of Experimental Physics, Otto-von-Guericke Universität Magdeburg, D-39016 Magdeburg, Germany.
authors.forename: T
authors.initials: T
authors.lastname: Trittel
authors.affiliation: Institute of Experimental Physics, Otto-von-Guericke Universität Magdeburg, D-39016 Magdeburg, Germany.
authors.forename: U
authors.initials: U
authors.lastname: Strachauer
authors.affiliation: Institute of Automation Engineering, Otto-von-Guericke Universität Magdeburg, D-39016 Magdeburg, Germany.
authors.forename: S
authors.initials: S
authors.lastname: Höme
authors.affiliation: Institute for Electronics, Signal Processing and Communications, Otto-von-Guericke Universität Magdeburg, D-39016 Magdeburg, Germany.
authors.forename: K
authors.initials: K
authors.lastname: Will
authors.affiliation: Institute of Experimental Physics, Otto-von-Guericke Universität Magdeburg, D-39016 Magdeburg, Germany.
authors.forename: R
authors.initials: R
authors.lastname: Stannarius