The fluctuations and correlations of matrix elements of cross sections are
investigated in open systems that are chaotic in the classical limit. The f
orm of the correlation functions is discussed within a statistical analysis
and tested in calculations for a damped quantum kicked rotator. We briefly
comment on the modifications expected for systems with slowly decaying cor
relations, a typical feature in mixed phase spaces. (C) 2001 Elsevier Scien
ce B.V. All rights reserved.