68 research outputs found
Anisotropic lattice with nonperturbative accuracy
We determine the nonperturbative anisotropic parameter of the gauge action in
the quenched approximation with less than 1% accuracy using the Sommer scale
measured by the L\"uscher-Weisz algorithm or smearing technique. We also study
the nonperturbative O(a)-improvement of the quark action. The bare quark
anisotropy is determined using the masses from the temporal and spatial
directions. For the determination of the improvement coefficients, we
apply the Schr\"odinger functional method.Comment: 3 pages, 5 figures, Lattice2004(improved
Anisotropic lattices for precision computations in heavy flavor physics
We study the anisotropic lattice QCD for precision computations of
heavy-light matrix elements. Our previous study in which the lattices are
calibrated with a few percent accuracy has already given results comparable to
the existing calculations. This suggests that even higher precision may be
achieved by a more precise calibration of anisotropic lattices. We describe our
strategy to tune the gauge and quark parameters with accuracies much less than
1 % in the quenched approximation.Comment: 3 papes, 2 figures, Lattice2003(heavy
Small airway disease associated with Sjögren’s syndrome: Clinico-pathological correlations
SummaryBackgroundRelationships among clinical, physiological, imaging and pathological findings of small airway disease associated with Sjögren’s syndrome have remained unclear.Subjects and methods: We retrospectively studied 14 patients who underwent surgical lung biopsy and who were diagnosed with small airway disease associated with primary or secondary Sjögren’s syndrome. We compared clinical, bronchoalveolar lavage, physiological, imaging and pathological findings between primary and secondary Sjögren’s syndrome. We scored HRCT and pathological abnormalities and investigated correlations among physiological, HRCT and pathological data, changes in physiological parameters and in HRCT scores after two years of treatment, as well as correlations between these values and pathological scores.ResultsBronchoalveolar lavage fluid, physiological, imaging and pathological findings of the airways did not significantly differ between primary and secondary Sjögren’s syndrome. Air trapping on HRCT negatively correlated with MEF50 and MEF25. Although lymphoid cell infiltration and peribronchiolar fibrosis were the most common pathologies, constrictive change scores correlated negatively with MEF50 and MEF25, positively with air trapping scores and negatively with improvements after therapy in MEF50, MEF25 and air trapping.ConclusionsConstrictive change was the most significant determinant of physiological and imaging presentations and of changes in these factors after therapy for small airway disease associated with Sjögren’s syndrome
Are Two z~6 Quasars Gravitationally Lensed ?
Several high-z (z > 5.7) quasars have been found in the course of Sloan
Digital Sky Survey. The presence of such very high-z quasars is expected to
give constraints on early structure formation. On one hand, it is suggested
that these most luminous objects at high redshift are biased toward the highly
magnified objects by gravitational lensing. To clarify the effect of
gravitational lensing on the high-z quasars, we began the imaging survey of
intervening lensing galaxies. Indeed our previous optical image showed that
SDSSp J104433.04+012502.2 at z=5.74 is gravitationally magnified by a factor 2.
In this paper, we report our new optical imaging of other two high-z quasars,
SDSSp J103027.10+052455.0 at z=6.28 and SDSSp J130608.26+035626.3 at z=5.99.
Since we find neither intervening galaxy nor counter image with i^{\prime} <
25.4-25.8 around each quasar, we conclude that they are not strongly magnified
regardless that a lens galaxy is dusty.Comment: 10 pages, 8 figures, Accepted for PAS
The Type Ic Hypernova SN 2002ap
Photometric and spectroscopic data of the energetic Type Ic supernova (SN)
2002ap are presented, and the properties of the SN are investigated through
models of its spectral evolution and its light curve. The SN is
spectroscopically similar to the "hypernova" SN 1997ef. However, its kinetic
energy [ erg] and the mass ejected (2.5-5
) are smaller, resulting in a faster-evolving light curve. The SN
synthesized of Ni, and its peak luminosity was
similar to that of normal SNe. Brightness alone should not be used to define a
hypernova, whose defining character, namely very broad spectral features, is
the result of a high kinetic energy. The likely main-sequence mass of the
progenitor star was 20-25 , which is also lower than that of both
hypernovae SNe 1997ef and 1998bw. SN 2002ap appears to lie at the low-energy
and low-mass end of the hypernova sequence as it is known so far. Observations
of the nebular spectrum, which is expected to dominate by summer 2002, are
necessary to confirm these values.Comment: 10 pages, 4 figures, accepted for publication in ApJL, 30 April 2002
(minor changes to match the accepted version, with figures being colored
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