Introduction

• Complex biological cell systems and SEE vulnerable systems have similar traits
• SEE defined as atypical behavior in an irradiated system

          *Microelectronic cells may upset from ion strike

          *Biological cells may suffer critical event far earlier than predicted

• Target theory describes events as a smooth function of total dose

           *SEU and early cell death should not be defined well by single hit    target theory that is generally used

• Target theory should be applied in a new way