95 research outputs found
Constitutive modeling of deformation behavior of high-entropy alloys with face-centered cubic crystal structure
A constitutive model based on the dislocation glide and deformation twinning is adapted to face-centered cubic high-entropy alloys (HEAs) as exemplified by the CrMnFeCoNi system. In this model, the total dislocation density is considered as the only internal variable, while the evolution equation describing its variation during plastic deformation is governed by the volume fraction of twinned material. The suitability of the model for describing the strain hardening behavior of HEAs was verified experimentally through compression tests on alloy CrMnFeCoNi and its microstructure characterization by electron backscatter diffraction and X-ray diffraction using synchrotron radiation. ? 2017 The Author(s). Published by Informa UK Limited, trading as Taylor & Francis Group.1111Ysciescopu
Measurement of the decay width of He
We have precisely measured decay width of \5LHe and
demonstrated significantly larger - overlap than expected
from the central repulsion - potential, which is derived from
YNG \Lambda$-nucleon interaction.Comment: 4 pages, 3 figure
Proton asymmetry in non-mesonic weak decay of light hypernuclei
We have obtained the decay asymmetry parameters in non-mesonic weak decay of
polarized Lambda-hypernuclei by measuring the proton asymmetry. The polarized
Lambda-hypernuclei, 5_Lambda-He, 12_Lambda-C, and 11_Lambda-B, were produced in
high statistics via the (pi^+,k^+) reaction at 1.05 GeV/c in the forward
angles. Preliminary analysis shows that the decay asymmetry parameters are very
small for these s-shell and p-shell hypernuclei.Comment: 4pages, 4figures, International Conference on Hypernuclear and
Strange Particle Physics (HYP2003
pi^0 decay branching ratios of 5_Lambda-He and 12_Lambda-C hypernuclei
We precisely measured pi^0 branching ratios of 5_Lambda-He and 12_Lambda-C
hypernuclei produced via (pi^+,k^+) reaction. Using these pi^0 branching ratios
with the pi^- branching ratios and the lifetimes, we obtained the pi^0 decay
widths and the non-mesonic weak decay widths at high statistics with the
accuracy of ~5 % (stat) for both hypernuclei.Comment: 4pages, 4figures, International Conference on Hypernuclear and
Strange Particle Physics (HYP2003
Nucleon-nucleon coincidence measurement in the non-mesonic weak decay of 5_Lambda-He and 12_Lambda-C hypernuclei
We have measured both yields of neutron-proton and neutron-neutron pairs
emitted from the non-mesonic weak decay process of 5_Lambda-He and 12_Lambda-C
hypernuclei produced via the (pi^+,K^+) reaction for the first time. We
observed clean back-to-back correlation of the np- and nn-pairs in the
coincidence spectra for both hypernuclei. The ratio of those back-to-back pair
yields, Nnn / Nnp, must be close to the ratio of neutron- and proton-induced
decay widths of the decay, Gn(Lambda n -> nn)/Gp(Lambda p -> np). The obtained
ratios for each hypernuclei support recent calculations based on short-range
interactions.Comment: 4 pages, 1 figure, International Nuclear Physics Conference (INPC
2004), Goteborg, Sweden, June 27 - July 2, 2004, to appear in Nuclear Physics
Coincidence Measurement of the Nonmesonic Weak Decay of ^{12}_{Lambda}C
We have measured the angular correlation of the pair nucleons np and nn
emitted from the nonmesonic weak decay (NMWD) of ^{12}_{Lambda}C produced via
the (pi^+,K^+) reaction in coincidence measurement. The Lambda p -> np and
Lambda n -> nn modes were clearly identified by measuring the back-to-back
correlation of the emitted nucleon pairs which is the characteristic of
two-body kinematics. From the measured nucleon pair numbers N_{nn} and N_{np},
the ratio Gamma_n/Gamma_p of the partial decay widths Gamma_n(Lambda n -> nn)
and Gamma_p(Lambda p -> np) of ^{12}_{Lambda}C was extracted to be
0.51+-0.13(stat) +- 0.05(syst); this result is almost free from the ambiguity
due to the nuclear final state interaction and 3-body decay process, which were
inherent in the previous results. The obtained Gamma_n/Gamma_p ratio of
^{12}_{Lambda}C (p-shell) is close to that of ^5_{Lambda}He (s-shell). The
results are consistent with those of recent theoretical calculations.Comment: 13 pages, 4figures, 1 table,re-submitted to Physics Letters
Neutron and proton energy spectra from the non-mesonic weak decays of 5_Lambda-He and 12_Lambda-C
We have simultaneously measured the energy spectra of neutrons and protons
emitted in the non-mesonic weak decays of 5_Lambda-He and 12_Lambda-C
hypernuclei produced via the (pi^+,k^+) reaction with much higher statistics
over those of previous experiments. The neutron-to-proton yield ratios for both
hypernuclei at a high energy threshold (60 MeV) were approximately equal to
two, which suggests that the ratio of the neutron- and proton-induced decay
channels, Gn(Lambda n -> nn)/Gp(Lambda p -> np), is about 0.5. In the neutron
energy spectra, we found that the yield of the low-energy component is
unexpectedly large, even for 5_Lambda-He.Comment: 13pages, 4figures, submitted to Physics Letters
Treatment Outcomes of Patients With Multidrug-Resistant and Extensively Drug-Resistant Tuberculosis According to Drug Susceptibility Testing to First- and Second-line Drugs: An Individual Patient Data Meta-analysis
The clinical validity of drug susceptibility testing (DST) for pyrazinamide, ethambutol, and second-line antituberculosis drugs is uncertain. In an individual patient data meta-analysis of 8955 patients with confirmed multidrug-resistant tuberculosis, DST results for these drugs were associated with treatment outcome
Biópsia do miocárdio em cães: acesso minimamente invasivo por cirurgia torácica videoassistida
Measurement of the Bs Lifetime in Fully and Partially Reconstructed Bs -> Ds- (phi pi-)X Decays in pbar-p Collisions at sqrt(s) = 1.96 TeV
We present a measurement of the Bs lifetime in fully and partially
reconstructed Bs -> Ds(phi pi)X decays in 1.3 fb-1 of pbar-p collisions at
sqrt(s) = 1.96 TeV collected by the CDF II detector at the Fermilab Tevatron.
We measure tau(Bs) = 1.518 +/- 0.041 (stat.) +/- 0.027 (syst.) ps. The ratio of
this result and the world average B0 lifetime yields tau(Bs)/tau(B0) = 0.99
+/-0.03, which is in agreement with recent theoretical predictions.Comment: submitted to Phys. Rev. Let
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