arXivDaily arXiv每日学术速递 周一至周五更新
arXiv 0806.0458nucl-th
收藏

核子-核子散射中重子共振的夸克模型

Quark models of dibaryon resonances in nucleon-nucleon scattering

J. L. Ping, H. X. Huang, H. R. Pang, Fan Wang, C. W. Wong

备注：
14 pages, 6 tables, 6 figures; added supplementary results, added/deleted references, added 1 figure
发表信息：
Phys.Rev.C79:024001,2009
阅读 PDF
arXiv 页面 ↗HTML 原文 ↗

摘要：

我们寻找$ΔΔ$和$NΔ$共振通过计算$NN$散射相移的两个相互作用的重子集团的夸克明确耦合到这些重子通道。两个唯象的非相对论手征夸克模型给出了相似的低能$NN$性质，但却给出了明显不同的重子共振结构。在手征夸克模型（ChQM）中，重子系统在$NN$ $S$ -波中不共振，这与实验SP 07 $NN$分波散射振幅一致。在夸克离域和色屏蔽模型（QDCSM）中，当核子尺寸$b$低于0.53 fm时，$S$波NN共振消失。两个夸克模型都给出了一个$IJ^P = 03^+$ $ΔΔ$共振。在$b=0.52 $ fm（重子谱所支持的值）处，具有二次（线性）约束的ChQM的共振质量为2390（2420）MeV，QDCSM的共振质量为2360 MeV。从$^3D_3^{NN}$通道中可以看出，这种共振是已知的等辐射ABC结构的一个有希望的候选者，在CELSIUS-WASA协作组最近报告的2410 MeV的$pn$ $\to $ $dππ$产生截面中可以更清楚地看到。在等矢量重子区，我们的夸克模型给出了一个束缚或几乎束缚的$^5S_2^{ΔΔ}$态，它能引起$^1D_2^{NN}$共振。所用的夸克模型都没有束缚可能产生奇宇称共振的$NΔ$ $P$ -态。

英文摘要：

We look for $ΔΔ$ and $NΔ$ resonances by calculating $NN$ scattering phase shifts of two interacting baryon clusters of quarks with explicit coupling to these dibaryon channels. Two phenomenological nonrelativistic chiral quark models giving similar low-energy $NN$ properties are found to give significantly different dibaryon resonance structures. In the chiral quark model (ChQM), the dibaryon system does not resonate in the $NN$ $S$-waves, in agreement with the experimental SP07 $NN$ partial-wave scattering amplitudes. In the quark delocalization and color screening model (QDCSM), the $S$-wave NN resonances disappear when the nucleon size $b$ falls below 0.53 fm. Both quark models give an $IJ^P = 03^+$ $ΔΔ$ resonance. At $b=0.52 $fm, the value favored by baryon spectrum, the resonance mass is 2390 (2420) MeV for the ChQM with quadratic (linear) confinement, and 2360 MeV for the QDCSM. Accessible from the $^3D_3^{NN}$ channel, this resonance is a promising candidate for the known isoscalar ABC structure seen more clearly in the $pn$$\to $$dππ$ production cross section at 2410 MeV in the recent preliminary data reported by the CELSIUS-WASA Collaboration. In the isovector dibaryon sector, our quark models give a bound or almost bound $^5S_2^{ΔΔ}$ state that can give rise to a $^1D_2^{NN}$ resonance. None of the quark models used has bound $NΔ$ $P$-states that might generate odd-parity resonances.

机构、总结、中文摘要均由AI分析而来，可能存在错误，请以论文正文为准。

↑