13,949 research outputs found
Investigation of kilovolt ion sputtering second quarterly progress report
Kilovolt ion sputtering - electron beam focusing of cesium ion beam, radiation detection in copper atoms, ultrahigh vacuum system construction, and spectrometer pulse heigh
Investigation of kilovolt ion sputtering Quarterly progress report, May - Jul. 1966
Aluminum sputtering, and neutron activation analysis after cesium ion bombardmen
Aerodynamic Study of a Wing-fuselage Combination Employing a Wing Swept Back 63 Degrees : Effectiveness at Supersonic Speeds of a 30-percent Chord, 50-percent Semispan Elevon as a Lateral Control Device
Aerodynamic Study of a Wing-fuselage Combination Employing a Wing Swept Back 63 Degrees : Effectiveness of an Elevon as a Longitudinal Control and the Effects of Camber and Twist on the Maximum Lift-drag Ratio at Supersonic Speeds
Nonequilibrium Approach to Bloch-Peierls-Berry Dynamics
We examine the Bloch-Peierls-Berry dynamics under a classical nonequilibrium
dynamical formulation. In this formulation all coordinates in phase space
formed by the position and crystal momentum space are treated on equal footing.
Explicitly demonstrations of the no (naive) Liouville theorem and of the
validity of Darboux theorem are given. The explicit equilibrium distribution
function is obtained. The similarities and differences to previous approaches
are discussed. Our results confirm the richness of the Bloch-Peierls-Berry
dynamics
A nullstellensatz for sequences over F_p
Let p be a prime and let A=(a_1,...,a_l) be a sequence of nonzero elements in
F_p. In this paper, we study the set of all 0-1 solutions to the equation a_1
x_1 + ... + a_l x_l = 0. We prove that whenever l >= p, this set actually
characterizes A up to a nonzero multiplicative constant, which is no longer
true for l < p. The critical case l=p is of particular interest. In this
context, we prove that whenever l=p and A is nonconstant, the above equation
has at least p-1 minimal 0-1 solutions, thus refining a theorem of Olson. The
subcritical case l=p-1 is studied in detail also. Our approach is algebraic in
nature and relies on the Combinatorial Nullstellensatz as well as on a Vosper
type theorem.Comment: 23 page
Formation of cosmological mass condensation within a FRW universe: exact general relativistic solutions
Within the framework of an exact general relativistic formulation of gluing
manifolds, we consider the problem of matching an inhomogeneous overdense
region to a Friedmann-Robertson-Walker background universe in the general
spherical symmetric case of pressure-free models. It is shown that, in general,
the matching is only possible through a thin shell, a fact ignored in the
literature. In addition to this, in subhorizon cases where the matching is
possible, an intermediate underdense region will necessarily arise.Comment: 6 page
Moving Wigner Glasses and Smectics: Dynamics of Disordered Wigner Crystals
We examine the dynamics of driven classical Wigner solids interacting with
quenched disorder from charged impurities. For strong disorder, the initial
motion is plastic -- in the form of crossing winding channels. For increasing
drive, the disordered Wigner glass can reorder to a moving Wigner smectic --
with the electrons moving in non-crossing 1D channels. These different dynamic
phases can be related to the conduction noise and I(V) curves. For strong
disorder, we show criticality in the voltage onset just above depinning. We
also obtain the dynamic phase diagram for driven Wigner solids and prove that
there is a finite threshold for transverse sliding, recently found
experimentally.Comment: 4 pages, 4 postscript figure
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