Searching for the Next Yukawa Phase of QCD

Abstract

QCD predicts that the interactions between quarks and gluons change from a confining to a screened Yukawa form above a critical temperature $T_c\sim 150$ MeV. In this talk, I review some of the key observables in heavy ion reactions which are being used to search for this new partonic Yukawa phase at SPS and RHIC. These include collective observables such as $d{E}_{\perp }/dy{d}^2{p}_{\perp }$, meson interferometry, jet quenching, and $J/\psi$ suppression.

Comments: 24 pages (PTPTex style files included) with 26 eps,ps figures using epsf,psfig. To appear in Proc. of 14th Nishinomiya-Yukawa Memorial Symposium Nov. 1999, Japan; updated with a critique of the CERN press release Feb. 8, 2000