Home 2D Images Maps by emission process Maps by viewing angle	An important factor to consider when creating maps of a relativistic jet is time-delay effects, the result of the photon crossing time exceeding the evolutionary time scale of the jet. We compare maps that are made without accounting for time-delay effects (`static') to those generated using many epochs. Comparing the static maps ( Maps 20 and 23) to their time-delay counterparts (Maps 2 and 7) , we see that the maps of the static jet have a higher peak intensity, and the static jet has many more bright features than the time-delay jet, making it brighter overall. In the time-delayed maps much of any line-of-sight's lifetime was spent in an earlier state of the computational domain. As the jet evolves over time, changes in pressure boost the emissivity. These changes begin with the formation of the bow, and in later times include such features as re-thermalizing shocks driven by Kelvin-Helmholtz instabilities. In early times there is little emission because very few features are present, and they occupy only a small region of the computational space. Many of the lines-of-sight do not start `brightening' until the last several epochs. But the static jet was made with the last epoch of the simulation, in which the pressure is at the maximum and the features of the jet are extended. The lines-of-sight in the static jet spend their entire life in a high pressure, high emissivity jet. They are much more likely to encounter a feature that will increase their flux. Thus, there are many more `bright' lines-of-sight in the static jet than in its time-delayed cousin. Another effect of time-delay is smearing ? the loss of distinct radio features. Compare Map 2 to Map 20, maps at 15°, made with the pressure model. In Map 2, the time-delayed case, there is one major bright feature. But in Map 20, the static case, there are a series of six bright spots running down the center line of the jet. Comparing Map 7 and Map 23, at 25°, made with the c_s model, we see even greater changes in morphology. Map 7, the time-delayed case, has only one very bright feature, and nearly featureless extended emission, but Map 23 has not only a large bright core, but also several bright features running along the axis of the jet, and has complex extended emission. Accounting for time-delay effects in the transfer calculation is important as they lead to important changes in intensity and morphology. Jet 1 at 15° and modeled by pressure, using time delay. Jet 1 at 25° and modeled by sound speed, using time delay. Jet 1 viewed at 15° and modeled using pressure, without time delay. Jet 1 viewed at 25° and modeled using sound speed, without time delay.
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