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1.
近年来,在研究两体束缚态方面,H·Suura和他的合作者做了一系列工作,取得了较好的成果。他在文献[1]中,定义了一个规范不变的夸克——反夸克两体振幅,提出了一个等时的相对论方程,以代替Bethe—Salpeter方程,来确定夸克和反夸克构成的介子质量  相似文献   

2.
本文在重正化的相对论量子场理论框架中导出了包含介子和重子的无限系统的相对论HF方程。方程的导出是以一个图解近似和重子传播子的Dyson方程为基础。结果得到了一组带有一个关于单粒子光谱自洽条件的耦合的,非线性的重子自能的积分方程。对模型参数重正代之后可以复制核物质的饱和特性,HF结果在低密到中等密度处类似于平均场(Hartree)近似  相似文献   

3.
超对称理论(SUSY)是TeV能级以上新物理的一种备受关注的可能理论框架.在该理论中,预言了超对称伴粒子的存在.其中,超对称粒子-最轻标量轻子τ1的寿命可能比较长,有可能与其他粒子形成超对称束缚态.采用Spinless Salpeter方程来描述超对称束缚态.Spinless Salpeter方程是Bethe-Salpeter方程的一种很好的近似,是Schrodinger方程的相对论推广.一般情况,Spinless Salpeter方程没有解析解,所以用数值方法求解Spinless Salpeter方程得到超对称束缚态τe,τμ,τp(或它们的反粒子)的质谱(或者束缚能).  相似文献   

4.
计算了DDσ相互作用的形状因子和耦合常数. 为了把D0介子具有内部结构的效应考虑进去,用Bethe Salpeter振幅来描述重介子态. 夸克流在重介子态之间的矩阵元通过Mandelstam修正过的Gell Mann Low方法计算. 对于这一方法所要求的Bethe Salpeter不可约核,采用了最低阶近似. 在得到DDσ相互作用的形状因子后,计算了DDσ的耦合常数.  相似文献   

5.
文献[1]提出了一个具有内部相对论性的介子结构模型。我们发现,0~(- )介子和1_(--)S波介子的Bethe—Salpeter(以下简称BS)振幅的旋量结构强烈地依赖于位势的旋量结构。若在BS方程中取投影位势V~((A))=V((T))=0,则由0~(- )介子和1~(--)S波介子的BS方程解出的旋量结构分别对应于相应介子的类自由旋量结构。在这种旋量结构中,只有  相似文献   

6.
从伸缩子-胶子有效耦合理论得到的重夸克势(Dilaton)势出发,计算了重介子的轻子衰变和辐射跃迁宽度,并与Cornell势所得到的相应结果作了比较.结果表明,Dilaton势的计算结果比Cornell势的相应结果更好地符合实验数据.  相似文献   

7.
夸克囚禁库仑-谐振迭加势与二步势、类分子势重夸克偶素能谱的比较吴邦惠(物理系)应用各种类型的相对论或非相对论方程研究夸克偶素(qq)能谱的性质,对于揭示夸克间相互作用的特点是有意义的.文[1~5]曾用多种不同形式的位势对0-和1-介子进行了研究,得到...  相似文献   

8.
本文研究了重Hybrid介子QQg。从重夸克偶素QQ位势写出QQg体系中QQ,Qg,Qg间的有效位势,并采用谐子势得到了胶子球对称分布下的QQ介子的质量谱及其波函数的解析表达式。  相似文献   

9.
用两种方法计算子核物质中π介子传播了的极化插入.通过计算π介子的色散关系,发现在低动量转移区相对论与非相对论的差别很小;πNN的膺标量与膺矢量耦合之间的差别即使对大动量转移区也很小;在所有情况下,没有π凝聚现象出现.  相似文献   

10.
在重夸克势模型理论框架下,研究了重介子谱的色屏蔽效应,结果表明,具有真空色屏蔽效应的重夸克势对重介子的实验能谱给出了更好的理论解释。  相似文献   

11.
The discovery of the prolific Ordovician Red River reservoirs in 1995 in southeastern Saskatchewan was the catalyst for extensive exploration activity which resulted in the discovery of more than 15 new Red River pools. The best yields of Red River production to date have been from dolomite reservoirs. Understanding the processes of dolomitization is, therefore, crucial for the prediction of the connectivity, spatial distribution and heterogeneity of dolomite reservoirs.The Red River reservoirs in the Midale area consist of 3~4 thin dolomitized zones, with a total thickness of about 20 m, which occur at the top of the Yeoman Formation. Two types of replacement dolomite were recognized in the Red River reservoir: dolomitized burrow infills and dolomitized host matrix. The spatial distribution of dolomite suggests that burrowing organisms played an important role in facilitating the fluid flow in the backfilled sediments. This resulted in penecontemporaneous dolomitization of burrow infills by normal seawater. The dolomite in the host matrix is interpreted as having occurred at shallow burial by evaporitic seawater during precipitation of Lake Almar anhydrite that immediately overlies the Yeoman Formation. However, the low δ18O values of dolomited burrow infills (-5.9‰~ -7.8‰, PDB) and matrix dolomites (-6.6‰~ -8.1‰, avg. -7.4‰ PDB) compared to the estimated values for the late Ordovician marine dolomite could be attributed to modification and alteration of dolomite at higher temperatures during deeper burial, which could also be responsible for its 87Sr/86Sr ratios (0.7084~0.7088) that are higher than suggested for the late Ordovician seawaters (0.7078~0.7080). The trace amounts of saddle dolomite cement in the Red River carbonates are probably related to "cannibalization" of earlier replacement dolomite during the chemical compaction.  相似文献   

12.
AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…  相似文献   

13.
本文叙述了对海南岛及其毗邻大陆边缘白垩纪到第四纪地层岩石进行古地磁研究的全部工作过程。通过分析岩石中剩余磁矢量的磁偏角及磁倾角的变化,提出海南岛白垩纪以来经历的构造演化模式如下:早期伴随顺时针旋转而向南迁移,后期伴随逆时针转动并向北运移。联系该地区及邻区的地质、地球物理资料,对海南岛上述的构造地体运动提出以下认识:北部湾内早期有一拉张作用,主要是该作用使湾内地壳显著伸长减薄,形成北部湾盆地。从而导致了海南岛的早期构造运动,而海南岛后期的构造运动则主要是受南海海底扩张的影响。海南地体运动规律的阐明对于了解北部湾油气盆地的形成演化有重要的理论和实际意义。  相似文献   

14.
Various applications relevant to the exciton dynamics,such as the organic solar cell,the large-area organic light-emitting diodes and the thermoelectricity,are operating under temperature gradient.The potential abnormal behavior of the exicton dynamics driven by the temperature difference may affect the efficiency and performance of the corresponding devices.In the above situations,the exciton dynamics under temperature difference is mixed with  相似文献   

15.
The elongation method,originally proposed by Imamura was further developed for many years in our group.As a method towards O(N)with high efficiency and high accuracy for any dimensional systems.This treatment designed for one-dimensional(ID)polymers is now available for three-dimensional(3D)systems,but geometry optimization is now possible only for 1D-systems.As an approach toward post-Hartree-Fock,it was also extended to  相似文献   

16.
17.
The explosive growth of the Internet and database applications has driven database to be more scalable and available, and able to support on-line scaling without interrupting service. To support more client's queries without downtime and degrading the response time, more nodes have to be scaled up while the database is running. This paper presents the overview of scalable and available database that satisfies the above characteristics. And we propose a novel on-line scaling method. Our method improves the existing on-line scaling method for fast response time and higher throughputs. Our proposed method reduces unnecessary network use, i.e. , we decrease the number of data copy by reusing the backup data. Also, our on-line scaling operation can be processed parallel by selecting adequate nodes as new node. Our performance study shows that our method results in significant reduction in data copy time.  相似文献   

18.
R-Tree is a good structure for spatial searching. But in this indexing structure,either the sequence of nodes in the same level or sequence of traveling these nodes when queries are made is random. Since the possibility that the object appears in different MBR which have the same parents node is different, if we make the subnode who has the most possibility be traveled first, the time cost will be decreased in most of the cases. In some case, the possibility of a point belong to a rectangle will shows direct proportion with the size of the rectangle. But this conclusion is based on an assumption that the objects are symmetrically distributing in the area and this assumption is not always coming into existence. Now we found a more direct parameter to scale the possibility and made a little change on the structure of R-tree, to increase the possibility of founding the satisfying answer in the front sub trees. We names this structure probability based arranged R-tree (PBAR-tree).  相似文献   

19.
The geographic information service is enabled by the advancements in general Web service technology and the focused efforts of the OGC in defining XML-based Web GIS service. Based on these models, this paper addresses the issue of services chaining,the process of combining or pipelining results from several interoperable GIS Web Services to create a customized solution. This paper presents a mediated chaining architecture in which a specific service takes responsibility for performing the process that describes a service chain. We designed the Spatial Information Process Language (SIPL) for dynamic modeling and describing the service chain, also a prototype of the Spatial Information Process Execution Engine (SIPEE) is implemented for executing processes written in SIPL. Discussion of measures to improve the functionality and performance of such system will be included.  相似文献   

20.
Advances in wireless technologies and positioning technologies and spread of wireless devices, an interest in LBS (Location Based Service) is arising. To provide location based service, tracking data should have been stored in moving object database management system (called MODBMS) with proper policies and managed efficiently. So the methods which acquire the location information at regular time intervals then, store and manage have been studied. In this paper, we suggest tracking data management techniques using topology that is corresponding to the moving path of moving object. In our techniques, we update the MODBMS when moving object arrived at a street intersection or a curved road which is represented as the node in topology and predict the location at past and future with attribute of topology and linear function. In this technique, location data that are corresponding to the node in topology are stored, thus reduce the number of update and amount of data. Also in case predicting the location,because topology are used as well as existing location information, accuracy for prediction is increased than applying linear function or spline function.  相似文献   

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