5.6 The double ratio of R c $_{AA}$( p$_{T}$ ) to R b $_{AA}$( p$_{T}$ ) predictions for Rhic using Eq. (5.1) for AdS/CFT and WHDG [152] for pQCD with a range of input parameters. While the hardening of the pro- duction spectrum reduces the dramatic bunching at Rhic as compared to $_{Lhc}$, the lower temperature at Rhic means the AdS/CFT drag formalism is applicable to higher momenta. Note that R cb is plotted to only 50 GeV for $_{Rhic}$. . . . . . . 135 6.1 The two diagrams contributing to the 0 th order in opacity pho- ton/gluon radiation spectrum. Note the inclusion of the radia- tion from the away side jet, which is usually ignored in pQCD calculations. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 141 6.2 (Color online) 0 th order radiative energy loss for (a) charm and (b) bottom quarks. All results are to leader order (LO) in 1 /E $^{+}$. One sees that the largest effect (50-150%) comes from including the (1 − x ) 2 prefactor and that filling in the “dead cone” with the massive photon is a rather small one (5-20%). Comparison with m$_{γ}$ = 0 yields the magnitude of the LO Ter-Mikayelian effect (10-40%). . . . . . . . . . . . . . . . . . . . . . . . . . 142 xx