High pT suppression & radiative parton energy loss

• Multiple final-state gluon radiation off the produced

• hard parton induced by the traversed dense

• colored medium:

  • Mean parton energy loss probes meadium properties:
  • DE ~ gluon (gluon density)
  • DE ~ DL2 (medium length)
  • Energy is carried away by gluon bremsstrahung
  • outside jet cone: dE/dx ~ s k2T
  • Expanding vs. static plasma:
  • E1-D =(20/RA)Estat ~15·Estat (0=0.2 fm/c, RA=6 fm)

• Well above energy loss in cold nuclear matter:

• • BDMPS: DE(T=250 MeV) ~ 15·DE(T=0),
  • dE/dx ~0.5 GeV/fm (HERMES eA data), FNAL E772: dE/dx ~0.2 GeV/fm (D.Y. pA data)

Notes: