down quark meaning in English
(物)下夸克
下夸克
Examples
- In summary , the up and down quarks make up all the nuclei and electrons orbiting around nuclei form atoms
总括来说，上夸克和下夸克组成原子核，而电子则围绕原子核而形成原子。 - Proton is , in turn , made up of two up quarks and one down quark . neutron is made up of two down quarks and one up quark
质子的内部是三粒夸克：两粒上夸克和一粒下夸克uud中子的内部也是三粒夸克：一粒上夸克和两粒下夸克udd 。 - There has been many papers to discuss the in - medium quark and gluon condensates in nuclear matter which use the models with su ( 2 ) l su ( 2 ) r sym - metry . now , we make use of the chiral model su ( 3 ) l su ( 3 ) n including the baryon octet to discuss the quark condensate < qq > in strange matter , where q is an up or down quark field . on the one hand , from the experimetal data , it is found that < qq > vac = - ( 225 25mev ) 3 , on the other hand , with the hellmann - feynman theorem , quark condensate can be evaluated on the hadronic level . in this paper , we will investigate the quark condensate in strange matter with the chiral symmetry su ( 3 ) l x su ( 3 ) rspontaneous breaking lagrangian to obtain the variation of the quark condensate in the strange matter when the baryon number change . it can be applied to understand the neutron stars when the neutron star are considered to be constructed by the strange matter . because nertron stars are homogeneous and at very low temperature , we will use the mean - field approximation and zero temperature throughout this paper
鉴于已有大量文献讨论了核物质中的夸克凝聚，本文将讨论在奇异物质中的夸克凝聚。而在介质中的夸克凝聚的基本公式可由hellmann - feynman理论导出，所以运用手征对称自发破缺拉氏量以及平均场近似，我们就可以讨论在奇异物质中的夸克凝聚，由所计算的结果表明： ( 1 )奇异物质中的夸克凝聚随奇异物质密度的增大而单调减小。 ( 2 ) -凝聚的出现对衰减率有影响。