在Π(L0)∩R≠φ的条件下,本文讨论了具有中间亏指数的对称微分算式l(y)的自共轭域,其中Π(L0)是由l(y)生成的最小算子L0的正则型域.使用方程l(y)=λ(0y),(λ0∈Π(L0)∩R)的实参数L^2-解,我们对最大算子域DM进行新的分解,由此得到l(y)的自共轭域新的完全解析刻画,其中自共轭边界条件中矩阵M,N的确定与l(y)=λ(0y)在无穷远点的性质无关,仅与其在t=0点初始值的选择有关.由于自共轭算子谱是实的,使用实参数λ0不仅有利于我们找到方程的显解,更重要的是可以得到谱的有关信息.
This paper deals with the self-adjoint domains of a singular symmetric differential expression l(y) with middle deficiency indices,under the condition that∏(L0)∩R≠φ, where∏(L0) is the regularity domain of the corresponding minimal operator L0.Using the real parameter L^2-solutions of the equation l(y) =λ0y withλ0∈∏(L0)∩R,we obtain a complete analytic description of the self-adjoint domains of l(y) by giving a new decomposition of the maximal operator domain DM.And the description is independent of the properties of l(y) at infinity(the determine of matrices M and N only depends the initial value of the solutions of l(y) =λ0y).Because the spectrum of self-adjoint operators is real, the advantage of using real parameterλ0 is not only because it is,in general,easier to find explicit solutions but,more importantly,it yields information about the spectrum.