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排序方式: 共有974条查询结果,搜索用时 312 毫秒
1.
Behnam Mohammadi 《中国物理C(英文版)》2022,46(2):023107-023107-8
In this study, the heavy to heavy decay of \begin{document}$ B^0_s\rightarrow D^{*+}D^- $\end{document} ![]()
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is evaluated through the factorization approach by using the final state interaction as an effective correction. Under the factorization approach, this decay mode occurs only through the annihilation process, so a small amount is produced. Feynman's rules state that six meson pairs can be assumed for the intermediate states before the final meson pairs are produced. By taking into account the effects of twelve final state interaction diagrams in the calculations, a significant correction is obtained. These effects correct the value of the branching ratio obtained by the pure factorization approach from \begin{document}$ (2.41\pm1.37)\times10^{-5} $\end{document} ![]()
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to \begin{document}$ (8.27\pm2.23)\times10^{-5} $\end{document} ![]()
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. The value obtained for the branching ratio of the \begin{document}$ B^0_s\rightarrow D^{*+}D^- $\end{document} ![]()
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decay is consistent with the experimental results. 相似文献
2.
Luis P. Castro Rita C. Guerra Nguyen Minh Tuan 《Mathematical Methods in the Applied Sciences》2020,43(7):4835-4846
We propose four new convolutions exhibiting convenient factorization properties associated with two finite interval integral transformations of Fourier-type together with their norm inequalities. Moreover, we study the solvability of a class of integral equations of Wiener-Hopf plus Hankel type (on finite intervals) with the help of the factorization identities of such convolutions. Fourier-type series are used to produce the solution formula of such equations, and a Shannon-type sampling formula is also obtained. 相似文献
3.
4.
Sina Hedayat 《代数通讯》2017,45(4):1711-1718
A proper ideal of a commutative ring is called pseudo-irreducible if it cannot be written as a product of two comaximal proper ideals. In this paper, we give a necessary and su?cient condition for every proper ideal of a commutative ring to be a product of pairwise comaximal pseudo-irreducible ideals. Examples of such rings include Laskerian rings, or more generally J-Noetherian rings and ZD-rings. We study when certain classes of rings satisfy this condition. 相似文献
5.
The Hamilton–Waterloo problem asks for a 2‐factorization of (for v odd) or minus a 1‐factor (for v even) into ‐factors and ‐factors. We completely solve the Hamilton–Waterloo problem in the case of C3‐factors and ‐factors for . 相似文献
6.
《Journal of Pure and Applied Algebra》2023,227(2):107191
In a previous work, we have introduced a weakening of Quillen model categories called weak model categories. They still allow all the usual constructions of model category theory, but are easier to construct and are in some sense better behaved. In this paper we continue to develop their general theory by introducing combinatorial and accessible weak model categories. We give simple necessary and sufficient conditions under which such a weak model category can be extended into a left and/or right semi-model category. As an application, we recover Cisinski-Olschok theory and generalize it to weak and semi-model categories. We also provide general existence theorems for both left and right Bousfield localization of combinatorial and accessible weak model structures, which combined with the results above gives existence results for left and right Bousfield localization of combinatorial and accessible left and right semi-model categories, generalizing previous results of Barwick. Surprisingly, we show that any left or right Bousfield localization of an accessible or combinatorial Quillen model category always exists, without properness assumptions, and is simultaneously both a left and a right semi-model category, without necessarily being a Quillen model category itself. 相似文献
7.
Salman H. Abbas 《应用数学和力学(英文版)》1996,17(12):1141-1146
THE THEORETICAL COST OF SEQUENTIAL AND PARALLEL ALGORITHMS FOR SOLVING LINEAR SYSTEMS OF EQUATIONSSalmanH.Abbas(ReceivedMay24... 相似文献
8.
绕旋转圆柱流动涡尾流结构和临界状态特性 总被引:1,自引:1,他引:1
采用作者提出的基于区域分解,有限差分法与涡法杂交的数值方法,结合高阶隐式差分格式,和以修正的不完全LU分解为预处理器的共轭梯度法作求解器,系统地研究了雷诺数Re=1000,旋转速度比α∈(0.5,3.25)范围内,绕旋转圆柱从突然起到充分发展,长时间内尾流旋涡结构和阻力,升力系数的变化规律,计算所得流动图案与实验流场显示符合很好。数值试验证帝了临界状态的存在,并首次给出了临界状态时的旋涡结构特性。 相似文献
9.
A. G. Shannon† 《International Journal of Mathematical Education in Science & Technology》2013,44(4):497-507
The semantic differential—one approach to attitude measurement— basically records a combination of a person's associations with a particular concept with a scaling procedure. This paper considers the implications of such a device for teachers of mathematics. 相似文献
10.