There exists experimental evidence that a dibaryon resonance d' with quantum numbers J^P=0^-,T=0 and mass 2065 MeV could be the origin of the narrow peak in the (\pi^+ ,\pi^- ) double charge exchange cross--sections on nuclei. We investigate the six--quark system with these quantum--numbers within the constituent quark model, with linear confinement, effective one--gluon exchange at short range and chiral interactions between quarks (\pi and \sigma exchange). We classify all possible six quark states with J^P=0^-,T=0, and with N=1 and N=3 harmonic oscillator excitations, using different reduction chains. The six--quark Hamiltonian is diagonalized in the basis including the unique N=1 state and the 10 most important states from the N=3 shell. We find, that with most of the possible sets of parameters, the mass of such a "dibaryon" lies above the N(939)+N^\ast(1535) threshold. The only possibility to describe the supposed d'(2065) in the present context is to reduce the confinement strength to very small values, however at the expense of describing the negative parity resonances N^\ast. We also analyze the J^P=0^-,T=2,N=1 six--quark state.
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机译：有实验证据表明，量子数为J ^ P = 0 ^-，T = 0且质量为2065 MeV的二重子共振d'可能是（\ pi ^ +，\ pi ^-）双峰中窄峰的起源。原子核上的电荷交换截面。我们研究了组成夸克模型中具有这些量子数的六夸克系统，具有线性约束，短距离内有效的一胶子交换以及夸克之间的手性相互作用（\ pi和\ sigma交换）。我们使用不同的归约链，将所有可能的六个夸克状态分类为J ^ P = 0 ^-，T = 0，以及N = 1和N = 3谐波振荡器激励。六夸克哈密顿量在包括唯一N = 1状态和N = 3壳中的10个最重要状态的基础上被对角线化。我们发现，对于大多数可能的参数集，这种“双子”的质量位于N（939）+ N ^ \ ast（1535）阈值之上。在当前上下文中描述假定的d'（2065）的唯一可能性是将限制强度减小到非常小的值，但是以描述负的奇偶共振N ^ \ ast为代价。我们还分析了J ^ P = 0 ^-，T = 2，N = 1六夸克状态。
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