Finite temperature dynamic structure function of the free Fermi gas

A detailed discussion of the coherent and incoherent dynamic structure func tion of the free Fermi gas at finite temperature is presented. Their behavi or and evolution with the momentum transfer and the temperature is analyzed , while particular attention is paid to the way in which their relative con tribution changes with respect to the (T) over tilde=0 case. The influence of thermal effects on the lowest order sum rules of the coherent and incohe rent responses is also discussed. Finally, the scaling properties of the re sponses at high momentum transfer as a function of the temperature are also analyzed. (C) 1999 Published by Elsevier Science B.V. All rights reserved.