Theoretical study of dynamic behavior of exotic atoms

研究了总角动量J=1的由~4He、~1H(及其同位素)和一个介子组成的介子分子Palphamu的退激X射线能谱。结果表明，在手掌的光谱中有一个较小的第二峰，其寿命比以前的计算结果延长了三倍。我们得到了11个J=0的共振态和12个J=1的共振态，以及9个J=0的共振态和10个J=1的(Dttu)^+共振态。某些共振能相对于Muon原子的n=2能级小于D2的解离能，因此这些态可能在Muon催化的聚变中起一定的作用。利用超径向绝热展开方法，在热能下研究了DMU+t碰撞。与以前用扭曲原子轨道方法计算得到的结果吻合较好。利用满足正确渐近边界条件的雅可比坐标系，计算了一个复杂的介子分子[(DtmU)De]的形成速率。得到的速率比以前的计算大了一个数量级，与实验结果相吻合。用TCDW方法和二级Born近似计算了正电子的形成截面。

X-ray spectrum due to the deexcitation of a muonic molecule palphamu with total angular momentum J=1 composed of ^4He, ^1H (and its isotopes), and a muon was investigated. It was shown that there is a small second peak in the spectrum of palphamu and the life time of the muonic molecules is three times longer than that determined by a previous calculation. We found 11 resonant states with J=0 and 12 with J=1 for (ddmu)^+, and 9 states with J=0 and 10 with J=1 for (dtmu)^+. Some of the resonant energies, relative to the n=2 level of the muonic atoms, are less than than the dissociation energy of D_2, and therefore these states may play some role in muon-catalyzed fusion. Using the hyperradial adiabatic expansion method, dmu + t collisions are studied at thermal energies. Reasonable agreement with a previous calculation by the distorted-atomic-orbital method was obtained. The formation rate of a complex muonic molecule[(dtmu)dee] was calculated using the Jacobi coordinate system that satisfies the correct asymptotic boundary conditions. The obtained rate is larger than a previous calculation by one order of magnitude and agrees with the experiment. The cross sections for positronium formation were calculated by means of the TCDW method and the second Born approximation.