Figure 7. Energy distribution analysis.

The effect on the annihilation location for (a) three postulated initial energy distributions. As the trap depth is about 540 mK, most, but not all, of the anti-atoms beyond 540 mK will be untrapped31,38. (b) The F=1 time-reversed CDF of the simulated annihilations during the magnet shutdown for the three distributions, following the labelling in (a). The black points plot the time-reversed CDF of the experimental events (which mainly appear as a band behind the red Maxwellian line.) The event data agrees well with the Maxwellian distribution. (c) A typical distribution in y of late annihilations (those occurring between 20 and 22 ms). (d) The reverse cumulative average, 〈y|t〉, for the three distributions, as defined in the text. For (c) and (d), F=80; as expected, the plotted lines in these last two graphs show little dependence on the postulated energy distribution.