Can We Observe the Quark Gluon Plasma in Cosmic Ray Showers ?
  The possibility of detection of some features of high energy particle interactions with detectors placed at medium depths underground through studies on high energy muons is investigated. These muons carry information about the early interactions occurring during the development of the hadron cascade near the top of the atmosphere. They might reveal the effects resulting from creation of quark gluon plasma in interactions of ultra high energy cosmic ray iron nuclei with air nuclei. 
Jan Ridky