使用馬鞍點-複旋轉的計算方法研究鈹原子自基態的光游離化. 光子的能量範圍為25至122電子伏特. 計算中需要很準確的波函數, 才能有高精確度的結果. 基態波函數為滿核加上關聯性的波函數. 對於在連續能譜中的共振態1s2s^2 2p, 1s2p^3, 1s2s^2 3p ^1P^o 都是一個內層電子被激發的自游離態, 其能量與能寬也計算至很高的準確度. 並計算其Auger衰變比例, 以檢驗鍾光組的自旋排列理論. 似鈹離子的這些能態也求出並與文獻中的實驗值和其他理論結果相比較.

The photoionization cross section (PICS) of Be from the ground state is studied with the saddle-point complex-rotation method for photon energies from 25 to 122 eV. A full-core plus correlation wave function is used for the ground state. For the resonances in the continuum, the energy and width for the singly core-excited Be $1s2s^2np\,^1P^o$ (n=2-6) are calculated to high precision. The PICS are studied with single open channel approximation as well as fully coupled open channels. The Auger decay branching ratios of these states are studied to check the spin alignment theory recently proposed by Chung. These results are compared with the previous theoretical and experimental data in the literature. Our Energy and width of $1s2s^22p$ are 115.513 eV and 36.6 meV and those of $1s2s^23p$ are 121.420 eV and 50.4 meV which agree with the experiment of Caldwell et al.

\bibitem{Caldwell90} C. D. Caldwell, M. G. Flemming, M. O. Krause, P. van
der Meulen, C. Pan and A. F. Starace, Phys. Rev. A{\bf 41} 542 (1990).
\bibitem{Chung97} K. T. Chung, Phys. Rev. Lett {\bf 78},1416 (1997).
\bibitem{Chung90} K. T. Chung ,Phys. Rev. A{\bf 42} 5732 (1990).
\bibitem{VoKy92} L. Voky, H. E. Saraph, W. Eissner, Z. W. Liu and H. P.
Kelly, Phys. Rev. A {\bf 46}, 3945 (1992).
\bibitem{spin} K. T. Chung, Phys. Rev. A {\bf 59}, 2065 (1999).
\bibitem{Jimenez99} J. Jim\'{e}nez-Mier, S. Schaphorst, C. D. Caldwell, and
M.O. Krause, J. Phys. B {\bf 32} 4301 (1999).
\bibitem{saddle} K. T. Chung, Phys. Rev. A {\bf 20}, 1743(1979).
\bibitem{BeB} K. T. Chung, J. Phys. B: At. Mol. Phys. {\bf 23}, 2929 (1990).
\bibitem{C} K. T. Chung, Phys. Scr. {\bf 42}, 530 (1990).
\bibitem{O} K. T. Chung, Phys. Scr. {\bf 42}, 537 (1990).
\bibitem{3Po} K. T. Chung, Phys. Rev. A {\bf 42}, 645 (1990).
\bibitem{PofB} K. T. Chung, Chinese J. of Phys., {\bf 27}, 507 (1989).
\bibitem{complexrotation} K. T. Chung and B. F. Davis, Phys. Rev. A
{\bf 26},3278(1982)
\bibitem{photo2} K. T. Chung, Phys. Rev. A {\bf 56}, R3330(1997).
\bibitem{McKoy} T. N. Rescigno and V. McKoy, Phys. Rev. A {\bf 12},
522 (1975).
\bibitem{Rodbro} M. R{\o}dbro,R. Bruch and P. Bisgaard, J.Phys. B:
At. Mol. Phys. { \bf 12}, 2413 (1979).
\bibitem{boron} K. T. Chung and R. Bruch, Phys. Rev. A {\bf 28}, 1418(1983)
\bibitem{carbon} R. Bruch, K. T. Chung, W. L. Luken and J. L. Culberson, Phys. Rev. A {\bf 31}, 310(1985).
\bibitem{carbonMann} R. Mann, Phys. Rev. A {\bf 35}, 4988(1987)
\bibitem{OBruch} R. Bruch,S Datz,P. D. Miller,P.L. Pepmiller,H. F. Krause,
J. K. Swenson and N. Stolterfoht, Phys. Rev. A {\bf 36}, 394(1987).
\bibitem{Theooxygen} M. H. Chen, Phys. Rev. A {\bf 31}, 1449(1985)
\bibitem{Ne91} R. Bruch, D. Schneider, M. H. Chen, K. T. Chung,
and B. F. Davis, Phys. Rev A {\bf 44}, 5659 (1991).
\bibitem{a32o} Nicolaides and Mercouris, Phys. Rev. A {\bf 36}, 390(1987)