Study of the ablative effects on tektite

The tumbling and surface roughness effects on the trajectory of entry tektite are studied in both free molecular and continuum flows. It was concluded that, while surface roughness has negligible effect on trajectory, the tumbling may play an important role in tektite trajectory and the consequent ablation, provided the body shape is different from a sphere. A shape factor was a good parameter for correlations between body shape and tumbling effects

Study of the ablative effects on tektites

Equations are presented which provide approximate parameters describing surface heating and tektite deceleration during atmosphere passage. Numerical estimates of these parameters using typical initial and ambient conditions support the conclusion that the commonly assumed trajectories would not have produced some of the observed surface markings. It is suggested that tektites did not enter the atmosphere singly but rather in a swarm dense enough to afford wake shielding according to a shock envelope model which is proposed. A further aerodynamic mechanism is described which is compatible with hemispherical pits occurring on tektite surfaces

Electronic charge reconstruction of doped Mott insulators in multilayered nanostructures

Dynamical mean-field theory is employed to calculate the electronic charge reconstruction of multilayered inhomogeneous devices composed of semi-infinite metallic lead layers sandwiching barrier planes of a strongly correlated material (that can be tuned through the metal-insulator Mott transition). The main focus is on barriers that are doped Mott insulators, and how the electronic charge reconstruction can create well-defined Mott insulating regions in a device whose thickness is governed by intrinsic materials properties, and hence may be able to be reproducibly made.Comment: 9 pages, 8 figure

Rigidity theorems for submetries in positive curvature

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