205,175 research outputs found
Time-Dependent Variational Approach to the Non-Abelian Pure Gauge Theory
The time-dependent variational approach to the pure Yang-Mills gauge theory,
especially a color su(3) gauge theory, is formulated in the functional
Schroedinger picture with a Gaussian wave functional approximation. The
equations of motion for the quantum gauge fields are formulated in the
Liouville-von Neumann form. This variational approach is applied in order to
derive the transport coefficients, such as the shear viscosity, for the pure
gluonic matter by using the linear response theory. As a result, the
contribution to the shear viscosity from the quantum gluons is zero up to the
lowest order of the coupling g in the quantum gluonic matter.Comment: 19 pages, no figures, using PTPTeX.cl
The NSNS High Energy Beam Transport Line
In the National Spallation Neutron Source (NSNS) design, a 180 meter long
transport line connects the 1 GeV linac to an accumulator ring. The linac beam
has a current of 28 mA, pulse length of 1 ms, and 60 Hz rep rate. The high
energy transport line consists of sixteen 60 degrees FODO cells, and
accommodates a 90 degrees achromatic bend, an energy compressor, collimators,
part of injection system, and enough diagnostic devices to measure the beam
quality before injection. To reduce the uncontrolled beam losses, this line has
nine beam halo scrapers and very tight tolerances on both transverse and
longitudinal beam dynamics under space charge conditions. The design of this
line is presented.Comment: 3 pages, transfer line desig
Unified description of pairing, trionic and quarteting states for one-dimensional SU(4) attractive fermions
Paired states, trions and quarteting states in one-dimensional SU(4)
attractive fermions are investigated via exact Bethe ansatz calculations. In
particular, quantum phase transitions are identified and calculated from the
quarteting phase into normal Fermi liquid, trionic states and spin-2 paired
states which belong to the universality class of linear field-dependent
magnetization in the vicinity of critical points. Moreover, unified exact
results for the ground state energy, chemical potentials and complete phase
diagrams for isospin attractive fermions with external fields
are presented. Also identified are the magnetization plateaux of
and , where is the magnetization saturation value. The
universality of finite-size corrections and collective dispersion relations
provides a further test ground for low energy effective field theory.Comment: 13 pages, 4 figure
Local Spin Susceptibility of the S=1/2 Kagome Lattice in ZnCu3(OD)6Cl2
We report single-crystal 2-D NMR investigation of the nearly ideal spin S=1/2
kagome lattice ZnCu3(OD)6Cl2. We successfully identify 2-D NMR signals
originating from the nearest-neighbors of Cu2+ defects occupying Zn sites. From
the 2-D Knight shift measurements, we demonstrate that weakly interacting Cu2+
spins at these defects cause the large Curie-Weiss enhancement toward T=0
commonly observed in the bulk susceptibility data. We estimate the intrinsic
spin susceptibility of the kagome planes by subtracting defect contributions,
and explore several scenarios.Comment: 4 figures; published in PR-B Rapid Communication
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