共查询到20条相似文献,搜索用时 15 毫秒
1.
A diquark model is used to investigate single-charmed baryons.In this model,baryon is composed of two diquarks and an antiquark.Masses of lowest lying states with J~P=1/2~(±) are obtained.Baryons in our results are as heavy as other theoretic predictions and we suggest that the five-quark components should be considered in any three-quark model for studying the charmed baryons. 相似文献
2.
暗能量和重子数等曲率扰动 总被引:1,自引:0,他引:1
文章对作为暗能量候选者之一的Quintessence场与物质的相互作用及其在宇宙学中的应用进行了研究,通过引入Quintessence与重子流的耦合合理地解释了重子与反重子的不对称性.另外还详细地计算了重子数等曲率扰动. 相似文献
3.
4.
利用瞬时近似的Bethe-Salpeter方程,并且考虑了Dirac旋量中负能级分量对单胶子交换势的修正,对N、△重子谱进行了计算.结果发现负能级分量的考虑对势参数,尤其是对αs有显著的影响,但对整个N、△重子谱的改变不大. 相似文献
5.
JETP Letters - We study the radiative energy loss contribution to proton stopping in AA collisions. The analyses is performed within the light-cone path integral approach to induced gluon emission.... 相似文献
6.
Haosong YOU Chengjun XIA Xinmei ZHU Penghui CHEN Jianfeng XU Zhenyan LU Guangxiong PENG Renxin XU 《原子核物理评论》2022,39(3):302-310
在等效质量模型框架下,考虑线性禁闭和一阶微扰相互作用的贡献并通过拟合$ \mathrm{p} $ 、$ \mathrm{n}$ 、$\Lambda$ 和$ \Delta $ 的质量来得到模型参数。发现,等效质量模型能够较好地给出符合实验的重子质量谱。而禁闭强度$D$ 、强耦合常数$\alpha_{\rm{s}}$ 以及夸克质量因子$f$ 与微扰强度$C$ 之间都存在关联,并能够很好地用解析公式逼近。除此之外,单胶子交换相互作用的色磁部分在重子质量谱中起着重要作用,从而使自旋$J=1/2$ 和3/2的重子之间的质量差最高达到300 MeV。为了更好地描述超子质量,对于包含奇异夸克的一对夸克间的相互作用我们进一步采用不同的强耦合常数,其具体的模型参数通过拟合$ \Sigma $ 和$ \Xi $ 的质量得到。基于本工作得到的等效质量模型参数组,能够更好地描述$ \mathrm{ud}$ 夸克物质团、奇异子以及致密星。 相似文献
7.
8.
Valentina Mantovani-Sarti Alessandro Drago Vicente Vento Byung-Yoon Park 《Few-Body Systems》2013,54(1-4):513-516
We study the interaction between two B = 1 states in a chiral soliton model where baryons are described as non-topological solitons. By using the hedgehog solution for the B = 1 states we construct three possible B = 2 configurations to analyze the role of the relative orientation of the hedgehog quills in the dynamics. The strong dependence of the intersoliton interaction on these relative orientations reveals that studies of dense hadronic matter using this model should take into account their implications. 相似文献
9.
10.
在不同能量下, 利用核束缚能对虚光子四动量的平方项进行修正, 分别计算了Sn核碰撞中核束缚能对反应截面中湮灭项和康普顿散射项及K因子的影响。 结果表明, 核束缚能在小x区域对反应截面中湮灭项和康普顿散射项及K因子的影响明显, 并且能量越低这种影响越显著, 随着x2增大影响逐渐消失。 We made a revision of square of virtual photon four momentum by means of using nuclear bin ding energy formula in different energy, and we also made an accurate calculation for the effect of nuclear binding energy on K factor and Compton term and annihilate term in the Drell Yan process of the Sn Sn collision. The outcome indicates that the effect of nuclear binding energy on the annihilate term and the Compton term is marked in little x region and the effect will become more obvious with decrease of the energy and come to disappear with increase of the x. 相似文献
11.
13.
Yu-Bing DONG 《理论物理通讯》1995,24(4):439-446
A potential model with screened confinement is proposed to calculate baryon spectrum. The results show that with the consideration of the colour screening effect, the theoretical predictions for both positive and negative N and Δ systems can be improved simultaneously. Moreover, by utilizing the potential, the calculated spectra for strange baryons (contain s quark), such as ∧∑ and Ω, can fit the experimental data better. 相似文献
14.
L. Becker 《Annalen der Physik》1981,493(1):37-44
A quark model for baryon production at low pT is obtained as generalization of the quark-antiquark fusion model. The quark transverse momenta are taken into account using an average transverse mass of the quarks. This leads to the incorporation of both quark fusion and quark recombination into one model. The model is able to describe qualitative features of the reactions pp → (Δ, ¯Δ, ∑+, ∑?) + X at 12 and 24 GeV/c. 相似文献
15.
In this paper, by applying a simplified version of Lieb ‘s spin-refleetion-positivity method, which was recentlydeveloped by one of us [G.S. Tian and J.G. Wang, J. Phys. A: Math. Gen. 35 (2002) 941], we investigate some generalproperties of the boson-fermion Hamiltonian, which has been widely used as a phenomenological model to describe thereal-space pairing of electrons. On a mathematically rigorous basis, we prove that for either negative or positive couplingV, which represents the spontaneous decay and recombination process between boson and fermion in the model, thepairing energy of electrons is nonzero. Furthermore, we also show that the spin-excitation gap of the boson-fermionHamiltonian is always larger than its charged gap, as predicted by the pre-paired electron theory. 相似文献
16.
YANGKai-Hua Guang-Shan HANRu-Qi 《理论物理通讯》2003,40(2):215-220
In this paper, by applying a simplified version of Lieb‘s spin-reflection-positivity method, which was recently developed by one of us [G.S. Tian and J.G. Wang, J. Phys. A: Math. Gen. 35 (2002) 941], we investigate some general properties of the boeon-fermion Hamiltonlan, which has been widely used as a phenomenological model to describe the real-space pairing of electrons. On a mathematically rigorous basis, we prove that for either negative or positive couping V, which represents the spontaneous decay and recombination process between boson and fermion in the model, the pairing energy of electrons is nonzero. Furthermore, we also show that the spin-excitation gap of the boson-fermion Hamiltonian is always larger than its charged gap, as predicted by the pre-palred electron theory. 相似文献
17.
Using variational Monte-Carlo method and choosing an antiferromagnetic trial wave function,we have calculated the binding energies just off half-filling in one-dimensional Hubbard chains. We found the binding for the lattice length N being less than 40 in the degenerate case, but no binding at aU in the non-degenerate case. However, with lattice length increasing gradually, difference between the two cases becomes smaller and smaller. Finally, there is no binding at all no matter whether or not the chains have a degeneracy at the Fermi level in the non-interacting (U=0) limit. It may bean in,dication of the independence of the final calculation results on the boundary conajtions for the large enough system or in thermodynamic limit. 相似文献
18.
A chiral quark soliton model for the baryon embedded in nuclear medium is proposed. The effective vacuum expectation value of the scalar field felt up by a quark of the baryon in nuclear medium is estimated. The model is solved for the hedgehog baryon state in the semiclassical approximation and self-conskitent approach. Some static properties of the baryon embedded in nuclear medium are calculated. An increment in ra&ns af the baryon is obtained. The numerical results can be used to explain the A-dependence of EMC effect and vacqum pressure constants in nuclear medium. 相似文献
19.
WANG Qing-Wu LEE Xi-Guo 《理论物理通讯》2008,49(4):971-976
Baryon magnetic moments of p, n, ∑^+,∑^-,Ξ^0, Ξ^- and the beta decay ratios (G A/Gv ) of n → p, ∑^-→n and Ξ^0→∑^+ are calculated in a colored quark cluster model. With SU(3) breaking, the model gives a good fit to the experimental values of those baryon magnetic moments and the beta decay ratios. Our results show that the orbital motion has a significant contribution to the spin and magnetic moments of those baryons and the strange component in nucleon is small. 相似文献