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101.
102.
Zi-Long Li Xing-Yue Tan Zhu-Feng Zhang Zhen-Yang Wang Xin-Heng Guo 《中国物理C(英文版)》2023,47(1):013102-013102-8
In this study, we systematically investigated two-pseudoscalar meson systems with the Bethe-Salpeter equation in the ladder and instantaneous approximations. By solving the Bethe-Salpeter equation numerically with the kernel containing the one-particle exchange diagrams, we found that the \begin{document}$ K\bar{K} $\end{document} ![]()
![]()
, \begin{document}$ DK $\end{document} ![]()
![]()
, \begin{document}$ B\bar{K} $\end{document} ![]()
![]()
, \begin{document}$ D\bar{D} $\end{document} ![]()
![]()
, \begin{document}$ B\bar{B} $\end{document} ![]()
![]()
, \begin{document}$ BD $\end{document} ![]()
![]()
, \begin{document}$ D\bar{K} $\end{document} ![]()
![]()
, \begin{document}$ BK $\end{document} ![]()
![]()
, and \begin{document}$ B\bar{D} $\end{document} ![]()
![]()
systems with \begin{document}$ I=0 $\end{document} ![]()
![]()
can exist as bound states. We also studied the contributions from heavy meson (\begin{document}$ J/\psi $\end{document} ![]()
![]()
and \begin{document}$\Upsilon $\end{document} ![]()
![]()
) exchanges and found that the contributions from heavy meson exchanges cannot be ignored. 相似文献
103.
H. S. Tan M. K. Han P. Y. Hu J. H. Zheng S. C. Ng H. Gong 《Applied Physics A: Materials Science & Processing》1994,59(3):245-251
An electron trap having an energy level of 0.14 eV from the conduction band edge was found in the bulk of copper-diffused VPE-grown n-GaAs0.6P0.4 by conventional DLTS measurements and by pulse-duration dependent capacitance amplitude measurements. The capture cross section at room temperature is about 1.0×10–21 cm2 and has a weak temperature dependence. These properties are attributed to a non-repulsive center having a capturing mechanism which involves multiphonon emission processes with hardly any lattice relaxation. Evolution of the spatial distributions of the traps with time under junction electric field were studied. The results suggest that the trap is positively charged and has a high diffusivity under electric field. The center can thus be identified as positively charged interstitial copper ion rather than some form of copper complexes. 相似文献
104.
A new numerical method is proposed to solve the Boltzmann equation. A frame is set up by using a discrete velocity approximation in the infinite velocity space, but by considering only those distribution function points which are not too small. The distribution function points may occur anywhere in the infinite discrete velocity space and are not constrained to a pre-specified region. A fourth-order finite difference is used for the convection terms. A Monte Carlo-like method is applied to the discrete velocity model of the collision integral. The effort of the method is proportional to the number of discrete points. Numerical examples are given for the full Boltzmann equation and results for some benchmark problems are compared with analytical or prior solutions. 相似文献
105.
106.
Two-dimensional numerical results are presented for laser produced carbon plasmas evolving through the formation of the critical surface. These results show a novel reversal of the spontaneously generated magnetic field. 相似文献
107.
Vo Van Tan 《Bulletin of the Brazilian Mathematical Society》2010,41(3):355-387
Let M be a minimal compact surface, let Γ ⊂ M be a compact analytic sub-variety. Assume that X:= M \ Γ is Stein. Then we will show that X admits algebraic compactifications M
i
(resp. non algebraic compactifications $
\mathbb{M}_i
$
\mathbb{M}_i
) which are not birationally equivalent (resp. not bimeromorphically equivalent) iff X is biholomorphic to
相似文献
108.
本文给出了具有两个抛线解的中心对称三次系统存在在极限环的条件,它可能也是充要条件。 相似文献
109.
A laser diode directly end-pumped, passively Q-switched Nd:YVO4/Cr:YAG laser is presented in this paper. With 600 mW incident pump laser, Q-switched 1064 nm laser with an average power of 138 mW, pulse width of 19.8 ns, repetition rate of 170.1 kHz and peak power of 40.96 W is obtained. When a KTP crystal was inserted into the cavity, Q-switched 532 nm laser with an average power of 56 mW, pulse width of 28.4 ns, repetition rate of 118.2 kHz and peak power of 16.7 W is obtained at last. 相似文献
110.