作者：
Yuan, Y.;Lu, X. Q.*;Dong, J. Q.;Gong, X. Y.;Zhang, R. B.
期刊：
PHYSICS OF PLASMAS,2018年25(1):012510 ISSN：1070-664X
通讯作者：
Lu, X. Q.
作者机构：
[Yuan, Y.; Gong, X. Y.; Lu, X. Q.] Univ South China, Sch Nucl & Technol, Hengyang 421001, Peoples R China.;[Dong, J. Q.] Southwestern Inst Phys, Chengdu 610041, Sichuan, Peoples R China.;[Zhang, R. B.] Chinese Acad Sci, Inst Plasma Phys, Hefei 230031, Anhui, Peoples R China.
通讯机构：
[Lu, X. Q.] U;Univ South China, Sch Nucl & Technol, Hengyang 421001, Peoples R China.
关键词：
plasma magnetohydrodynamics;plasma simulation;plasma transport processes;tearing instability
摘要：
The effect of helical driven current on the m = 2/n = 1 tearing mode is studied numerically in a cylindrical geometry using the method of reduced magneto-hydro-dynamic simulation. The results show that the local persistent helical current drive from the beginning time can be applied to control the tearing modes, and will cause a rebound effect called flip instability when the driven current reaches a certain value. The current intensity threshold value for the occurrence of flip instability is about 0.00087I0. The method of controlling the development of tearing mode with comparative economy is given. If the local helical driven current is discontinuous, the magnetic island can be controlled within a certain range, and then, the tearing modes stop growing; thus, the flip instability can be avoided. We also find that the flip instability will become impatient with delay injection of the driven current because the high order harmonics have been developed in the original O-point. The tearing mode instability can be controlled by using the electron cyclotron current drive to reduce the gradient of the current intensity on the rational surfaces.
通讯机构：
School of Nuclear Science & Technology, University of South China, Hengyang, Hunan, China
关键词：
光致发光;食盐;辐射事故;剂量
摘要：
基于光致发光个人剂量监测系统In Light200,对1～100 m Gy辐照剂量范围内的食盐进行光致发光测量,分析了其光致发光信号的线性响应以及信号的稳定性;探究了不同自然光照时间和不同储存时间对食盐光致发光信号的影响。实验结果表明:食盐在1～100 m Gy辐照剂量范围内具有良好的线性响应和信号稳定性;信号在10 min的自然光照时间后降低到本底水平;信号在30 d的储存时间内几乎无衰减;食盐可用作辐射事故中验证重建的剂量材料。
期刊：
EUROPEAN PHYSICAL JOURNAL C,2018年78(10):1-8 ISSN：1434-6044
通讯作者：
Qi, Jing-Juan
作者机构：
[Qi, Jing-Juan; Guo, Xin-Heng] Beijing Normal Univ, Coll Nucl Sci & Technol, Beijing 100875, Peoples R China.;[Wang, Zhen-Yang] Ningbo Univ, Dept Phys, Ningbo 315211, Zhejiang, Peoples R China.;[Zhang, Zhen-Hua] Univ South China, Sch Nucl & Technol, Hengyang 421001, Hunan, Peoples R China.;[Xu, Jing] Yantai Univ, Dept Phys, Yantai 264005, Peoples R China.
通讯机构：
[Qi, Jing-Juan] B;Beijing Normal Univ, Coll Nucl Sci & Technol, Beijing 100875, Peoples R China.
摘要：
Within the QCD factorization approach, we study the CP violations in
$$B^-\rightarrow K^-\pi ^+\pi ^-$$
and
$$B^-\rightarrow K^- f_0(500)$$
decays. We find the experimental data of the localized CP asymmetry in
$$B^-\rightarrow K^-\pi ^+\pi ^-$$
decays in the region
$$m_{K^-\pi ^+}^2<15$$
$$\mathrm {GeV}^2$$
and
$$0.08<m_{\pi ^+\pi ^-}^2<0.66$$
$$\mathrm {GeV}^2$$
can be explained by the interference of two intermediate resonances,
$$\rho ^0(770)$$
and
$$f_0(500)$$
when the parameters in our interference model are in the allowed ranges, i.e. the relative strong phase
$$\delta \in [2.124, 5.976]$$
and the end-point divergence parameters
$$\rho _S\in [5.692, 8]$$
and
$$\phi _S \in [0, 2\pi ]$$
. With the obtained allowed ranges for
$$\rho _S$$
and
$$\phi _S$$
, we obtain the predictions for the CP asymmetry parameter
$$A_{CP} \in [-0.115, -0.151]$$
and the branching fraction
$${\mathcal {B}} \in [3.763, 20.014]\times 10^{-5}$$
for
$$B^-\rightarrow K^-f_0(500)$$
decay modes.
作者机构：
[Li, Xiao-Hua; Zhao, Jie-Cheng; Deng, Jun-Gang; Chen, Jiu-Long] Univ South China, Sch Nucl Sci & Technol, Hengyang 421001, Peoples R China.;[Wu, Xi-Jun] Univ South China, Sch Math & Phys, Hengyang 421001, Peoples R China.;[Li, Xiao-Hua] Univ South China, Cooperat Innovat Ctr Nucl Fuel Cycle Technol & Eq, Hengyang 421001, Peoples R China.;[Li, Xiao-Hua] Hunan Normal Univ, Key Lab Low Dimens Quantum Struct & Quantum Contr, Changsha 410081, Hunan, Peoples R China.
通讯机构：
[Wu, Xi-Jun] U;Univ South China, Sch Math & Phys, Hengyang 421001, Peoples R China.
关键词：
a decay;~(296)Og;hindrance factor;two-potential approach
摘要：
The present work is a continuation of our previous paper [J.-G. Deng, et al., Chin. Phys. C, 41: 124109 (2017)]. In the present work, the a decay half-life of the unknown nucleus 2960g is predicted within the two-potential approach and the hindrance factors of all 20 even-even nuclei in the same region as ~(296)Og, i.e. proton number 82<Z<126 and neutron number 152<N<184, from ~(250)Cm to ~(294)Og, are extracted. The prediction is 1.09 ms within a factor of 5.12. In addition, based on the latest experimental data, a new set of parameters of a decay hindrance factors for the even-even nuclei in this region, considering the shell effect and proton-neutron interaction, are obtained.
摘要：
基于两势方法(two–potential–approach,TPA)系统研究了偶-偶核、奇-A核和奇-奇核α衰变半衰期。为了考虑原子核的壳结构的影响而导致的实验半衰期与计算结果之间的偏差,引入了与α结团形成概率相关的禁戒因子和预形成因子。结合前期相关工作[X. D. Sun et al., Phys. Rev. C 93, 034316 (2016); X. D. Sun et al., Phys. Rev. C 95, 014319 (2017);X. D. Sun et al., Phys. Rev. C 95, 044303 (2017)],考虑到壳效应对α粒子预形成的影响,通过分析α衰变半衰期的实验数据,拟合得到了α粒子预形成因子/禁戒因子修正公式的参数,得到了α衰变预形成因子/禁戒因子的计算结果,证实了壳效应及质子-中子相互作用在α结团形成过程中起着重要的作用,离壳越近预形成概率越小离壳越远预形成概率越大。
摘要：
In this paper, a computer aided system is developed for analyzing and visualizing CT images with nasopharyngeal carcinoma. In the system, firstly, an effective registration method that combines global rigid registration algorithm and local multi-resolution symmetric Demons registration algorithm is applied to match the plain CT image and the contrast-enhanced CT image of the same patient. Secondly, a total probability map is generated to roughly locate the tumor and determine an initial seed in the tumor. Here, this map is derived from CT intensities of the plain CT image and the contrast-enhanced CT image of the same patient and from location of the nasopharynx. Thirdly, a region growing method with multi feature criteria is used to segment the tumor from the volume data. Finally, the tumor and head skin are reconstructed and visualized so that the size and location of tumor are displayed. The experimental results show that this system can be used as a medical auxiliary diagnostic tool for radiologists to observe the size and location of the tumor.
