Spectral properties and tensor products of quasi-*-A(n) operators

Abstract

In this paper, we  prove  that  the  spectrum,  Weyl  spectrum  and  Browder  spectrum  are  continuous  on the  class  of  all quasi-*-A(n)  operators. And we obtain a sufficient condition for a quasi-*-A(n) operator to be normal. Finally, we  consider  the tensor  products  of  quasi-*-A(n) operators,  giving a necessary  and  sufficient  condition for T\otimes S  to  be a quasi-*-A(n) operator  when T  and S  are  both  non-zero  operators.