ner_tags: O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B-CelestialObject O O O B-Citation O O O B-CelestialObject O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B-Citation I-Citation O O O O O B-CelestialObject O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B-Citation I-Citation O O O O O B-CelestialObject O O O O O O O O O O O O O O O O O O
tokens: of sight lines that cross through the z -axis of the domain behind the cloud’s head. The angles between each of these sight lines and the sight line through the cloud’s head were determined from the assumption that the observer was on Earth, 12.4 kpc ( L08 ) from the SC (see Figures 1 , 2 , and 4 ). Figure 5 (a) shows as a function of this angle for Model A at various epochs. For angles ≲30°, reaches a reasonably steady state by t = 300 Myr (i.e., the variation of from epoch to epoch is relatively small compared to earlier epochs). However, there is still some time variation of the profiles, due to the fact that the flow in the model HVC’s tail is not steady, and for the last few tens of megayears of the simulation, is drifting toward larger values for angles ≲15°. For Models B and C (Figures 5 (b) and (c), respectively), we find that also reaches a reasonably steady state by around t = 300 Myr, although again there is some time variation of the profiles. In addition, the Model C profiles exhibit gaps at some angles, meaning that there is no material above the high-velocity cutoff along the sight line at those particular angles. These gaps in the high-velocity material distribution are due to the higher-density ambient medium having a stronger braking effect on the cloud material than in the other models (this braking effect was noted in footnote 1 for a model with an even higher ambient density, for which the effect was more severe than in Model C). Figure 5. Fraction of the high-velocity material originating in the halo, , as a function of angular distance behind the cloud head, extracted from various epochs of Models A–C (top to bottom; see keys). The vertical dashed lines indicate the location of F16 's sight lines relative to the SC head. Figure 6 shows averaged over multiple epochs. Within the epoch-to-epoch variations, these averaged profiles are similar for Models A and B at the cloud head and at angles ≳20° behind the cloud head. The difference between the models at intermediate angles is because the Model A cloud fragments more than the Model B cloud (as noted above), leading to more rapid mixing in the first few kiloparsecs behind the cloud head. However, other than in the first few kiloparsecs behind the cloud head, the mixing results are not very sensitive to the assumed cooling rate. In contrast, the averaged profiles from Models A and C are similar at all angles, though this is in part due to the large time variation of the Model C profiles. These results suggest that the extent of mixing is not very sensitive to the assumed ambient density. Figure 6. sampled every 1 Myr and averaged over t = 300–400 Myr from Models A, B, and C (red, blue, and green, respectively). The colored bands indicate the standard deviation. The vertical dashed lines indicate the location of F16 's sight lines relative to the SC head. Figure 7 compares the averaged profiles calculated from versions of our reference model with different maximum resolutions.