Detection of X-ray Emission from the Warm-Hot Intergalactic Medium   through the Angular Autocorrelation Function with Chandra
  We have used the angular Autocorrelation Function (AcF) in a pointing with Chandra's ACIS-S instrument. However, we determined that the contribution of Chandra's background below 1 keV is too high to achieve reasonable sensitivity. 
Massimiliano Galeazzi, Anjali Gupta, Kevin Huffenberger, and Eugenio   Ursino
astro-ph.CO