Towards the application of the Maximum Entropy Method to finite   temperature Upsilon Spectroscopy
  According to the Narnhofer Thirring Theorem interacting systems at finite temperature cannot be described by particles with a sharp dispersion law. It is therefore mandatory to develop new methods to extract particle masses at finite temperature. The Maximum Entropy method offers a path to obtain the spectral function of a particle correlation function directly. We have implemented the method and tested it with zero temperature Upsilon correlation functions obtained from an NRQCD simulation. Results for different smearing functions are discussed. 
M. Oevers, C. Davies, J. Shigemitsu