6,441 research outputs found
Study of Light Scalar Meson Structure in decay
We study the quark structure of the sigma meson through the decay of
meson by constructing an effective Lagrangian for charmed mesons
interacting with light mesons based on the chiral symmetry and heavy quark
symmetry. Within the linear realization of the chiral symmetry, we include the
P-wave charmed mesons (, ) as the chiral partners of
(, ), and the light scalar mesons as the chiral partner of the
pseudoscalar mesons. In the light meson sector, both the and
states are incorporated respecting their different U(1)
transformation properties. We predict the decay width with
two pions in the channel, which can be tested in the future
experiment. We find that the width increases with the percentage of the
content in the sigma meson.Comment: 5 pages, 2 figures, Contribution to KMI Inauguration Conference
"Quest for the Origin of Particles and the Universe" (KMIIN), 24-26 Nov.
2011, KMI, Nagoya Universit
3D Measurement of Water and Bed Surface Shapes During the Formation of Sand Waves Using the Moving Optical Cutting Method
Source: ICHE Conference Archive - https://mdi-de.baw.de/icheArchive
Elastic Cross Sections for Electron Collisions with Molecules Relevant to Plasma Processing
Absolute electron-impact cross sections for molecular targets, including their radicals, are important in developing plasma reactors and testing various plasma processing gases. Low-energy electron collision data for these gases are sparse and only the limited cross section data are available. In this report, elastic cross sections for electron-polyatomic molecule collisions are compiled and reviewed for 17molecules relevant to plasma processing. Elastic cross sections are essential for the absolute scale conversion of inelastic cross sections, as well as for testing computational methods. Data are collected and reviewed for elastic differential, integral, and momentum transfer cross sections and, for each molecule, the recommended values of the cross section are presented. The literature has been surveyed through early 2010.This work is accomplished as a collaboration through APAN (Asia-Pacific Atomic Data Network: a network for dissemination of collisional data relevant to plasmas, discharges, materials, and biosciences). H.C. acknowledges a support by the National Research Foundation of Korea (Grant No. 20100000035), and M.J.B. and S.J.B. support from the Australian Research Council Center of Excellence for Antimatter-Matter Studies. Collaboration between NIFS and NFRI is also acknowledged for the Korea-Japan exchanges
Differential elastic electron scattering cross sections for CCl₄ by 1.5–100 eV energy electron impact
We report absolute elastic differential, integral and momentum transfer cross sections for electron interactions with CCl₄. The incident electron energy range is 1.5-100 eV, and the scattered electron angular range for the differential measurements varies from 15°-130°. The absolute scale of the differential cross section was set using the relative flow technique with helium as the reference species. Comparison with previous total cross sections shows good agreement. Atomic-like behaviour in this scattering system is shown here for the first time, and is further investigated by comparing the CCl₄ elastic cross sections to recent results on the halomethanes and atomic chlorine at higher impact energies [H. Kato, T. Asahina, H. Masui, M. Hoshino, H. Tanaka, H. Cho, O. Ingólfsson, F. Blanco, G. Garcia, S. J. Buckman, and M. J. Brunger, J. Chem. Phys. 132, 074309 (2010)].This work was conducted under the support of the
Japanese Ministry of Education, Sport, Culture and Technology.
H.K. acknowledges the Japan Society for the Promotion
of Science (JSPS) for his fellowships as grants-in-aid for scientific
research. S.J.B also acknowledges the JSPS Invitation
Fellowship for Research in Japan
Recommended from our members
Biomarkers of Inflammation and Fibrosis in Kawasaki Disease Patients Years After Initial Presentation With Low Ejection Fraction.
Background Coronary artery aneurysms and myocarditis are well-recognized complications of Kawasaki disease (KD) but no systematic evaluation of the consequences of myocarditis has been performed in the subset presenting with low ejection fraction (EF). We postulated that more severe myocardial inflammation as evidenced by low EF during the acute phase could lead to late myocardial fibrosis. Methods and Results We measured the carboxyterminal propeptide of procollagen type I (PIPC), soluble suppressor of tumorigenicity 2, galectin-3 (Gal-3), growth-differentiation factor-15, and calprotectin by ELISA in late convalescent blood samples from 16 KD patients who had an EF ≤55% on their initial echocardiogram. Results were compared with samples from sex- and age-matched KD patients with initial EF >60%. In the univariate analysis, the median Gal-3 and PIPC levels in the low EF group were significantly higher than those in the normal EF group (Gal-3: low EF 6.216 versus normal EF 4.976 mg/dL P=0.038, PIPC: low EF 427.4 versus normal EF 265.2 mg/dL, P=0.01). In a multivariable analysis, there were significant differences for Gal-3 and PIPC levels between the low and normal EF groups, adjusting for age, sex, and worst z score. Conclusions Convalescent KD patients with a history of low EF during the acute illness had significantly elevated levels of Gal-3 and PIPC when compared with matched-control KD patients with normal EF. These findings raise concern for myocardial fibrosis as a potential late sequela of the more severe myocarditis experienced by a subset of KD patients during the acute phase
X-Ray Study of the Outer Region of Abell 2142 with Suzaku
We observed outer regions of a bright cluster of galaxies A2142 with Suzaku.
Temperature and brightness structures were measured out to the virial radius
() with good sensitivity. We confirmed the temperature drop from 9 keV
around the cluster center to about 3.5 keV at , with the density
profile well approximated by the model with . Within
0.4\r_{200}, the entropy profile agrees with , as predicted by the
accretion shock model. The entropy slope becomes flatter in the outer region
and negative around . These features suggest that the intracluster
medium in the outer region is out of thermal equilibrium. Since the relaxation
timescale of electron-ion Coulomb collision is expected to be longer than the
elapsed time after shock heating at , one plausible reason of the low
entropy is the low electron temperature compared to that of ions. Other
possible explanations would be gas clumpiness, turbulence and bulk motions of
ICM\@. We also searched for a warm-hot intergalactic medium around
and set an upper limit on the oxygen line intensity. Assuming a line-of-sight
depth of 2 Mpc and oxygen abundance of 0.1 solar, the upper limit of an
overdensity is calculated to be 280 or 380, depending on the foreground
assumption.Comment: 14 pages, 8 figure
Absolute elastic differential cross sections for electron scattering by C6H5CH3 and C6H5CF3 at 1.5–200 eV: a comparative experimental and theoretical study with C6H6
We present absolute differential cross sections DCS for elastic scattering from two benzene derivatives
C6H5CH3 and C6H5CF3. The crossed-beam method was used in conjunction with the relative flow technique
using helium as the reference gas to obtain absolute values. Measurements were carried out for scattering
angles 15° –130° and impact energies 1.5–200 eV. DCS results for these two molecules were compared to
those of C6H6 from our previous study. We found that 1 these three molecules have DCS with very similar
magnitudes and shapes over the energy range 1.5–200 eV, although DCS for C6H5CF3 increase steeply toward
lower scattering angles due to the dipole moment induced long-range interaction at 1.5 and 4.5 eV, and 2 that
the molecular structure of the benzene ring significantly determines the collision dynamics. From the measured
DCS, elastic integral cross sections have been calculated. Furthermore, by employing a corrected form of the
independent-atom method known as the screen corrected additive rule, DCS calculations have been carried out
without any empirical parameter fittings, i.e., in an ab initio nature. Results show that the calculated DCS are
in excellent agreement with the experimental values at 50, 100, and 200 eV
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