9,435 research outputs found
Chiral Gauge Theory on Lattice with Domain Wall Fermions
We investigate a U(1) lattice chiral gauge theory with domain wall fermions
and compact gauge fixing. In the reduced model limit, our perturbative and
numerical investigations show that there exist no extra mirror chiral modes.
The longitudinal gauge degrees of freedom have no effect on the free domain
wall fermion spectrum consisting of opposite chiral modes at the domain wall
and at the anti-domain wall which have an exponentially damped overlap.Comment: 16 pages revtex, 5 postscript figures, PRD versio
Strongly coupled U(1) lattice gauge theory as a microscopic model of Yukawa theory
Dynamical chiral symmetry breaking in a strongly coupled U(1) lattice gauge
model with charged fermions and scalar is investigated by numerical simulation.
Several composite neutral states are observed, in particular a massive fermion.
In the vicinity of the tricritical point of this model we study the effective
Yukawa coupling between this fermion and the Goldstone boson. The perturbative
triviality bound of Yukawa models is nearly saturated. The theory is quite
similar to strongly coupled Yukawa models for sufficiently large coupling
except the occurrence of an additional state -- a gauge ball of mass about half
the mass of the fermion.Comment: 4 page
High Spatial Resolution Imaging of NGC 1068 in the Mid Infrared
Mid-infrared observations of the central source of NGC 1068 have been
obtained with a spatial resolution in the deconvolved image of 0.1" (~ 7pc).
The central source is extended by ~1" in the north-south direction but appears
unresolved in the east-west direction over most of its length. About two-thirds
of its flux can be ascribed to a core structure which is itself elongated
north-south and does not show a distinct unresolved compact source. The source
is strongly asymmetric, extending significantly further to the north than to
the south. The morphology of the mid-infrared emission appears similar to that
of the radio jet, and has features which correlate with the images in [O III].
Its 12.5-24.5 micron color temperature ranges from 215 to 260 K and does not
decrease smoothly with distance from the core. Silicate absorption is strongest
in the core and to the south and is small in the north.
The core, apparently containing two-thirds of the bolometric luminosity of
the inner 4" diameter area, may be explained by a thick, dusty torus near the
central AGN viewed at an angle of ~65 deg to its plane. There are, however,
detailed difficulties with existing models, especially the narrow east-west
width of the thin extended mid-infrared "tongue" to the north of the core. We
interpret the tongue as re-processed visual and ultraviolet radiation that is
strongly beamed and that originates in the AGN.Comment: 42 pages, 2 tables, 9 figures; Accepted for publication in A
Analysis of the Fusion Hindrance in Mass-symmetric Heavy Ion Reactions
The fusion hindrance, which is also denominated by the term extra-push, is
studied on mass-symmetric systems by the use of the liquid drop model with the
two-center parameterization. Following the idea that the fusion hindrance
exists only if the liquid drop barrier (saddle point) is located at the inner
side of the contact point after overcoming the outer Coulomb barrier, the
reactions in which two barriers are overlapped with each other are determined.
It is shown that there are many systems where the fusion hindrance does not
exist for the atomic number of projectile or target nucleus , while
for , all of the mass-symmetric reactions are fusion-hindered.Comment: 6 pages, 4 figures. to be published in Sci. in China
Connie Myers v. Albertsons, Inc. : Brief of Appellee
Appeal of the Judgment of Michael Glasmann Based upon a Jury Verdict Second Judicial District Court Weber County, State of Uta
Non-detection of a pulsar-powered nebula in Puppis A, and implications for the nature of the radio-quiet neutron star RX J0822-4300
We report on a deep radio search for a pulsar wind nebula associated with the
radio-quiet neutron star RX J0822-4300 in the supernova remnant Puppis A. The
well-determined properties of Puppis A allow us to constrain the size of any
nebula to less than 30 arcsec; however we find no evidence for such a source on
any spatial scale up to 30 arcmin. These non-detections result in an upper
limit on the radio luminosity of any pulsar-powered nebula which is three
orders of magnitude below what would be expected if RX J0822-4300 was an
energetic young radio pulsar beaming away from us, and cast doubt on a recent
claim of X-ray pulsations from this source. The lack of a radio nebula leads us
to conclude that RX J0822-4300 has properties very different from most young
radio pulsars, and that it represents a distinct population which may be as
numerous, or even more so, than radio pulsars.Comment: 5 pages, including 2 embedded EPS figures, uses emulateapj.sty.
Accepted to ApJ Letters (minor changes made following referee's report
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