52 research outputs found
Delta rho pi interaction leading to N* and Delta* resonances
We have performed a calculation for the three body system
by using the fixed center approximation to Faddeev equations, taking the
interaction between and , and, and and
from the chiral unitary approach. We find several peaks in the modulus
squared of the three-body scattering amplitude, indicating the existence of
resonances, which can be associated to known and and baryon states.Comment: Presented at the 21st European Conference on Few-Body Problems in
Physics, Salamanca, Spain, 30 August - 3 September 201
Pion electro-production in the Roper region in chiral quark models
We present a method to calculate pion electro-production amplitudes in a
coupled-channel framework incorporating quasi-bound quark-model states. The
method offers a clear prescription how to extract the resonant part of the
amplitudes, even in the presence of different decay channels and a strong
mixing of neighbouring resonances. The method is applied to the calculation of
the M1- and the S1- amplitudes in the P11 partial wave in a simple chiral quark
model. A good agreement with the observed M1- amplitude is found with a
significant contribution from the pion cloud. The same effect is also prominent
in the S1- amplitude but a rather uncertain data prevent us to draw a
definitive conclusion.Comment: 8 pages, 10 Postscript figures, Fig. 7 and Fig. 8 change
Hydrogen Susceptibility of Nanostructured Bainitic Steels
Abstract
Nanostructured steels with an ultimate tensile strength of 1.6 GPa were produced with austenite content varying from 0 to 35 vol pct. The effect on the mechanical properties was assessed after saturating the steel with hydrogen. Elongation was reduced to 2 to 5 pct and UTS to 65 to 70 pct of prior value. Thermal desorption measurements confirmed the higher solubility of hydrogen in the steel with higher austenite content. The level of hydrogen saturation was found to correlate to the total area of grain boundaries rather than to the volume fraction of retained austenite.This is the final version of the article. It was first available from Springer via http://dx.doi.org/10.1007/s11661-015-3221-
Hybrid Simulations for In-Line Visualisation of Welding State in Resistance Spot Welding
Cytogenetic effects of in vivo administration of methadone and 1-alpha-acetyl methadol (LAAM)
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