95 Chapter 4: Fluctuations in Jet Tomography [224] and Braaten-Thoma (BT) [229, 230] estimates of elastic (dashed curves). For light quarks, the elastic energy loss decreases more rapidly with energy than radiative energy loss, but even at 20 GeV the elastic is only 50% smaller than the radiative. From Fig. 4.2, we see that above E > 10 GeV, the light and charm quarks have similar elastic and inelastic energy losses. But due to the large mass effect [285, 298, 305, 379, 386, 387], both radiative and elastic energy losses remain significantly smaller for bottom quarks than for light and charm quarks. We present both TG and BT as a measure of the theoretical uncertainties of the Coulomb log. These are largest for the heaviest b quark, for which the leading log approximation [224, 229, 230] breaks down in the kinematic range accessible at Rhic as they are not ultrarelativistic. With advanced numerical covariant transport techniques [138] the theoretical errors on the elastic energy loss effects can be reduced considerably in the future. The quenched spectra of partons, hadrons, and leptons are calculated as in [374] from the generic pQCD convolution where Q denotes quarks and gluons. For charm and bottom, the initial quark spectrum, Ed $^{3}$σ ( Q ) /dp $^{3}$, is computed at next-to-leading order using the code 4.2 Theoretical Framework Ed $^{3}$σ ( e ) dp 3 = E$_{i}$d $^{3}$σ ( Q ) dp 3 i ⊗ P ( E$_{i}$ → E$_{f}$ ) ⊗ D ( Q → H$_{Q}$ ) ⊗ f ( H$_{Q}$ → e ) , (4.1)