1,670 research outputs found
Multichannel spectroscopy guide
System makes use of diverging duct walls for conducting the light from entrance slips to the conductors by means of multiple reflectors. This system simultaneously records, photoelectrically, the intensities of several closely spaceed narrow wavelengths in the ultraviolet and infrared areas of the spectrum
The wind-sock theory of comet tails
A method is reported for calculating the shapes of ionic comet tails that use the magnetic field along the tail to channel the tail plasma. The local momentum field in the solar wind determines magnetic field line locations along the tail. Thus, the magnetic field acts as a transparent wind sock in trapping field lines in the cometary plasma around the nucleus long enough to be effectively fastened to the comet's head
Experimental study of viscous low-density nozzle flows Final report
Electron beam measurements of gas densities and rotational temperatures in viscous nozzle flo
Hilbert Space of Isomorphic Representations of Bosonized Chiral
We analyse the Hilbert space structure of the isomorphic gauge non-invariant
and gauge invariant bosonized formulations of chiral for the particular
case of the Jackiw-Rajaraman parameter . The BRST subsidiary conditions
are found not to provide a sufficient criterium for defining physical states in
the Hilbert space and additional superselection rules must to be taken into
account. We examine the effect of the use of a redundant field algebra in
deriving basic properties of the model. We also discuss the constraint
structure of the gauge invariant formulation and show that the only primary
constraints are of first class.Comment: LaTeX, 19 page
The chiral and flavour projection of Dirac-Kahler fermions in the geometric discretization
It is shown that an exact chiral symmetry can be described for Dirac-Kahler
fermions using the two complexes of the geometric discretization. This
principle is extended to describe exact flavour projection and it is shown that
this necessitates the introduction of a new operator and two new structures of
complex. To describe simultaneous chiral and flavour projection, eight
complexes are needed in all and it is shown that projection leaves a single
flavour of chiral field on each.Comment: v2: 17 pages, Latex. 5 images eps. Added references, reformatted and
clarification of some point
Recursive Construction of Generator for Lagrangian Gauge Symmetries
We obtain, for a subclass of structure functions characterizing a first class
Hamiltonian system, recursive relations from which the general form of the
local symmetry transformations can be constructed in terms of the independent
gauge parameters. We apply this to a non-trivial Hamiltonian system involving
two primary constraints, as well as two secondary constraints of the Nambu-Goto
type.Comment: 10 pages, Late
Spin-dependent thermoelectric transport in HgTe/CdTe quantum wells
We analyze thermally induced spin and charge transport in HgTe/CdTe quantum
wells on the basis of the numerical non-equilibrium Green's function technique
in the linear response regime. In the topologically non-trivial regime, we find
a clear signature of the gap of the edge states due to their finite overlap
from opposite sample boundaries -- both in the charge Seebeck and spin Nernst
signal. We are able to fully understand the physical origin of the
thermoelectric transport signatures of edge and bulk states based on simple
analytical models. Interestingly, we derive that the spin Nernst signal is
related to the spin Hall conductance by a Mott-like relation which is exact to
all orders in the temperature difference between the warm and the cold
reservoir.Comment: 11 pages, 13 figures, submitted to PR
Zone Determinant Expansions for Nuclear Lattice Simulations
We introduce a new approximation to nucleon matrix determinants that is
physically motivated by chiral effective theory. The method involves breaking
the lattice into spatial zones and expanding the determinant in powers of the
boundary hopping parameter.Comment: 20 pages, 6 figures, revtex4 (version to appear in PRC
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