2,524 research outputs found
Principal Vertex Operator Representations for Toroidal Lie Algebras
In this paper we present the principal construction of the vertex operator
representation for toroidal Lie algebras.Comment: 29 pages, plain tex, no figure
Magnetic ordering and fluctuation in kagome lattice antiferromagnets, Fe and Cr jarosites
Jarosite family compounds, KFe_3(OH)_6(SO_4)_2, (abbreviate Fe jarosite), and
KCr_3(OH)_6(SO_4)_2, (Cr jarosite), are typical examples of the Heisenberg
antiferromagnet on the kagome lattice and have been investigated by means of
magnetization and NMR experiments. The susceptibility of Cr jarosite deviates
from Curie-Weiss law due to the short-range spin correlation below about 150 K
and shows the magnetic transition at 4.2 K, while Fe jarosite has the
transition at 65 K. The susceptibility data fit well with the calculated one on
the high temperature expansion for the Heisenberg antiferromagnet on the kagome
lattice. The values of exchange interaction of Cr jarosite and Fe jarosite are
derived to be J_Cr = 4.9 K and J_Fe = 23 K, respectively. The 1H-NMR spectra of
Fe jarosite suggest that the ordered spin structure is the q = 0 type with
positive chirality of the 120 degrees configuration. The transition is caused
by a weak single-ion type anisotropy. The spin-lattice relaxation rate, 1/T_1,
of Fe jarosite in the ordered phase decreases sharply with lowering the
temperature and can be well explained by the two-magnon process of spin wave
with the anisotropy.Comment: REVTeX, 14 pages with 5 figures. Submitted to Canadian Journal of
Physic
Study of basic bio-electrochemistry Sixth monthly progress report, 1-31 Aug. 1963
Contribution of hydrogen peroxide to electrode reaction in electrochemical cell by considering effect of catalyst on cell curren
Higher-dimensional WZW Model on K\"ahler Manifold and Toroidal Lie Algebra
We construct a generalization of the two-dimensional Wess-Zumino-Witten model
on a -dimensional K\"ahler manifold as a group-valued non-linear sigma
model with an anomaly term containing the K\"ahler form. The model is shown to
have an infinite-dimensional symmetry which generates an -toroidal Lie
algebra. The classical equation of motion turns out to be the
Donaldson-Uhlenbeck-Yau equation, which is a -dimensional generalization of
the self-dual Yang-Mills equation.Comment: 12 pages, Late
An imaging time-of-propagation system for charged particle identification at a super B factory
Super B factories that will further probe the flavor sector of the Standard
Model and physics beyond will demand excellent charged particle identification
(PID), particularly K/pi separation, for momenta up to 4 GeV/c, as well as the
ability to operate under beam backgrounds significantly higher than current B
factory experiments. We describe an Imaging Time-of-Propagation (iTOP) detector
which shows significant potential to meet these requirements. Photons emitted
from charged particle interactions in a Cerenkov radiator bar are internally
reflected to the end of the bar, where they are collected on a compact image
plane using photodetectors with fine spatial segmentation in two dimensions.
Precision measurements of photon arrival time are used to enhance the two
dimensional imaging, allowing the system to provide excellent PID capabilities
within a reduced detector envelope. Results of the ongoing optimization of the
geometric and physical properties of such a detector are presented, as well as
simulated PID performance. Validation of simulations is being performed using a
prototype in a cosmic ray test stand at the University of Hawaii.Comment: 3 pages, 5 figures, submitted to TIPP09 proceeding
Status of the CKM matrix
An updated determination of the parameters of the Cabibbo-Kobayashi-Maskawa
matrix is presented.Comment: 8 pages, 9 figures, uses espcrc2.sty. Talk given at the "7th Topical
Seminar on the Legacy of LEP and SLC", 8-11 October 2001, Siena (Italy
Supersymmetric Reflection Matrices
We briefly review the general structure of integrable particle theories in
1+1 dimensions having N=1 supersymmetry. Examples are specific perturbed
superconformal field theories (of Yang-Lee type) and the N=1 supersymmetric
sine-Gordon theory. We comment on the modifications that are required when the
N=1 supersymmetry algebra contains non-trivial topological charges.Comment: 7 pages, Revtex, 2 figures, talk given at the International Seminar
on Supersymmetry and Quantum Field Theory, dedicated to the memory of
D.V.Volkov, Kharkov (Ukraine), January 5-7, 199
Momentum Dependent Charge Excitations of Two-Leg Ladder: Resonant Inelastic X-ray Scattering of (La,Sr,Ca)14Cu24O41
Momentum dependent charge excitations of a two-leg ladder are investigated by
resonant inelastic x-ray scattering of (La,Sr,Ca)14Cu24O41. In contrast to the
case of a square lattice, momentum dependence of the Mott gap excitation of the
ladder exhibits little change upon hole-doping, indicating the formation of
hole pairs. Theoretical calculation based on a Hubbard model qualitatively
explains this feature. In addition, experimental data shows intraband
excitation as continuum intensity below the Mott gap and it appears at all the
momentum transfers simultaneously. The intensity of the intraband excitation is
proportional to the hole concentration of the ladder, which is consistent with
optical conductivity measurements.Comment: 7 page
Division Algebras and Extended N=2,4,8 SuperKdVs
The first example of an N=8 supersymmetric extension of the KdV equation is
here explicitly constructed. It involves 8 bosonic and 8 fermionic fields. It
corresponds to the unique N=8 solution based on a generalized hamiltonian
dynamics with (generalized) Poisson brackets given by the Non-associative N=8
Superconformal Algebra. The complete list of inequivalent classes of
parametric-dependent N=3 and N=4 superKdVs obtained from the ``Non-associative
N=8 SCA" is also furnished. Furthermore, a fundamental domain characterizing
the class of inequivalent N=4 superKdVs based on the "minimal N=4 SCA" is
given.Comment: 14 pages, LaTe
Orbital domain state and finite size scaling in ferromagnetic insulating manganites
55Mn and 139La NMR measurements on a high quality single crystal of
ferromagnetic (FM) La0.80Ca20MnO3 demonstrate the formation of localized
Mn(3+,4+) states below 70 K, accompanied with strong anomalous increase of
certain FM neutron Bragg peaks. (55,139)(1/T1) spin-lattice relaxation rates
diverge on approaching this temperature from below, signalling a genuine phase
transition at T(tr) approx. 70 K. The increased local magnetic anisotropy of
the low temperature phase, the cooling-rate dependence of the Bragg peaks, and
the observed finite size scaling of T(tr) with Ca (hole) doping, are suggestive
of freezing into an orbital domain state, precursor to a phase transition into
an inhomogeneous orbitally ordered state embodying hole-rich walls.Comment: 4 pages, 4 figure
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