中文

基于格点QCD与玻恩-奥本海默近似的Zb四夸克道研究

高能物理 - 格点 2021-03-02 v4 高能物理 - 唯象学

摘要

Belle实验发现了两个具有奇异夸克结构bˉbdˉu\bar bb\bar duZbZ_b强子。我们提出在静态bb夸克近似下对bˉbdˉu\bar bb\bar du系统进行的格点QCD研究,其中重夸克的总自旋固定为1。本征态的能量被确定为bbbˉ\bar b之间分离距离rr的函数。较低本征态与一个底夸克偶素和一个π介子相关。由BBˉB\bar B^*主导的本征态能量显著低于mB+mBm_B+m_{B^*},这表明在小的rr下存在可观的吸引。假设该本征态仅与BBˉB\bar B^*相关,我们提取了BBBˉ\bar B^*之间的吸引势V(r)V(r)。在所提取势下BBˉB\bar B^*的薛定谔方程导致在BBˉB\bar B^*阈值以下存在一个束缚态,其质量依赖于格点势的参数化形式。对于某些参数化,该束缚态非常接近BBˉB\bar B^*阈值,并在阈值以上的BBˉB\bar B^*速率中产生一个窄峰——这些特征可能与实验中的Zb(10610)Z_b(10610)相关。

关键词

引用

@article{arxiv.1912.02656,
  title  = {Zb tetraquark channel from lattice QCD and Born-Oppenheimer approximation},
  author = {S. Prelovsek and H. Bahtiyar and J. Petkovic},
  journal= {arXiv preprint arXiv:1912.02656},
  year   = {2021}
}

备注

5 pages and supplement. The submatrix of the correlation matrix was multiplied by a wrong overall constant, which affected the eigen-energies. All figures expect Fig. 1 are replaced in v4. The main conclusion does not change - Zb is related to attraction between B and B*. The correct potential is less attractive and it results only in one bound state (see Note added)