105 Chapter 4: Fluctuations in Jet Tomography well reproduced. The L$_{Q}$ are determined only to ∼ 0 . 5 fm accuracy, as this suffices for our purposes here. We show the comparison between approaches I and II for heavy quarks in Fig. 4.6 using L$_{c}$ = 4 . 5 and L$_{b}$ = 6 . 5 fm, and for gluons and light quarks in Fig. 4.7 using L$_{g}$ = 4 . 0 and L$_{u}$ = 5 . 0 fm; see Fig. 4.3 for a visual comparison of the input length distributions used. This hierarchy of Q -dependent length scales is in accord with that expected from Fig. 4.4. Figure 4.6: Heavy quark jet quenching before fragmentation into mesons for dN$_{g}$/dy = 1000 . Solid green curves show the results of approach I based on Eq. (4.4) including full geometric path length fluctuations and DGLV radiative and TG elastic energy loss for c and b quarks. Upper and lower yellow bands show predictions using approach II via Eq. (4.7) with effective path lengths taken as L$_{c}$ = 4 . 5 and L$_{b}$ = 6 . 5 fm. As previously noted in Fig. 4.2, the difference between TG and BT curves indicates the magnitude of theoretical uncertainties in the elastic energy loss.