The uncertainties of background contributions to J = 0 partial wave πK scattering phase shifts are carefully studied. We firstly point out that the circular cuts exhibit different characters in S1/1 and S3/2 waves. W...The uncertainties of background contributions to J = 0 partial wave πK scattering phase shifts are carefully studied. We firstly point out that the circular cuts exhibit different characters in S1/1 and S3/2 waves. While the former contributes negatively to the scattering length parameter, the latter contributes positively, i.e., has a wrong sign. This fact indicates that short range force contribu tions to the phase shift are non-negligible in the exotic channel. Nevertheless, it is verified that the κ pole will be affected only slightly with respect to the theoretical uncertainty in estimating the left hand cut contributions.展开更多
The pole position of the σ meson is determined using the recently proposednew unitarization method combined with the two-loop SU(2) X SU(2) chiral perturbation theoryresults. The scattering length parameters and the ...The pole position of the σ meson is determined using the recently proposednew unitarization method combined with the two-loop SU(2) X SU(2) chiral perturbation theoryresults. The scattering length parameters and the effective range parameters predicted by our methodare in good agreement with experimental results. It is found that M_σ = 542 ± 26 ± 39 MeV, Γ_σ= 546 ± 122 ± 25 MeV.展开更多
Single-walled carbon nanotubes (SWCNTs) illuminated by white light should appear colored due to resonance Rayleigh scattering. However, true-color imaging of SWCNTs on substrates has not been reported, because of th...Single-walled carbon nanotubes (SWCNTs) illuminated by white light should appear colored due to resonance Rayleigh scattering. However, true-color imaging of SWCNTs on substrates has not been reported, because of the extremely low scattering intensity of SWCNTs and the strong substrate scattering. Here we show that Rayleigh scattering can be greatly enhanced by the interface dipole enhancement effect. Consequently colorful SWCNTs on substrates can be directly imaged under an optical microscope by wide field supercontinuum laser illumination, which facilitates high throughput chirality assignment of individual SWCNTs. This approach, termed "Rayleigh imaging microscopy", is not restricted to SWCNTs, but widely applicable to a variety of nanomaterials, which enables the colorful nanoworld to be explored under optical microscopes.展开更多
基金The project supported in part by National Natural Science Foundations of China under Grant Nos. 10575002, 10421503, and 10491306.Acknowledgments It is a pleasure to thank Prof. Han-Qing Zheng for valuable discussions and a careful reading of the manuscript.
文摘The uncertainties of background contributions to J = 0 partial wave πK scattering phase shifts are carefully studied. We firstly point out that the circular cuts exhibit different characters in S1/1 and S3/2 waves. While the former contributes negatively to the scattering length parameter, the latter contributes positively, i.e., has a wrong sign. This fact indicates that short range force contribu tions to the phase shift are non-negligible in the exotic channel. Nevertheless, it is verified that the κ pole will be affected only slightly with respect to the theoretical uncertainty in estimating the left hand cut contributions.
文摘The pole position of the σ meson is determined using the recently proposednew unitarization method combined with the two-loop SU(2) X SU(2) chiral perturbation theoryresults. The scattering length parameters and the effective range parameters predicted by our methodare in good agreement with experimental results. It is found that M_σ = 542 ± 26 ± 39 MeV, Γ_σ= 546 ± 122 ± 25 MeV.
基金The authors would like to thank Prof. Feng Wang, Prof. Xuedong Bai, and Prof. Kaihui Liu for helpful discussions. This work was supported by the National Basic Research Program of China (No. 2012CB932301) and the National Natural Science Foundation of China (Nos. 90921012, 11321091, 51102144, 11274190, and 51102147).
文摘Single-walled carbon nanotubes (SWCNTs) illuminated by white light should appear colored due to resonance Rayleigh scattering. However, true-color imaging of SWCNTs on substrates has not been reported, because of the extremely low scattering intensity of SWCNTs and the strong substrate scattering. Here we show that Rayleigh scattering can be greatly enhanced by the interface dipole enhancement effect. Consequently colorful SWCNTs on substrates can be directly imaged under an optical microscope by wide field supercontinuum laser illumination, which facilitates high throughput chirality assignment of individual SWCNTs. This approach, termed "Rayleigh imaging microscopy", is not restricted to SWCNTs, but widely applicable to a variety of nanomaterials, which enables the colorful nanoworld to be explored under optical microscopes.