Conceptual illustration of particle emission in azimuth and relationship to elliptic flow and collectivity

<p>This set of images represents, in a schematic and simplified manner, the various scenarios for particle emission in high-energy interactions (heavy ions but also others). Individual images can be used alone or also in an animation explanatory sequence. The various versions are:</p> <ol> <li>The file `1-initialConditionIncoherentColored` shows how a number of particle-emitting sources will ultimately populate azimuth uniformly in case they emit incoherently.&nbsp;</li> <li>The file `2-initialConditionCoherentColored` shows how particle-emitting sources might generate a polar pattern in their particle emission provided any kind of overlap (e.g. strong interaction) leads to coherent emission.&nbsp;</li> <li>The file `3-initialConditionVelocityField` illustrates the concept of a common velocity field at the edges of the system. This is to be used, for instance, in a transition slide in which a speaker introduces some various limiting options of which entities actually have a common velocity.&nbsp;</li> <li>The file `4-initialConditionMassOrdering` illustrates the possibility that hadrons are emitted in a common velocity field, leading to mass-ordered elliptic flow such as the one observed at low transverse momentum in heavy-ion collisions. This serves to directly illustrate the patterns that are numerically created by e.g. the blast-wave model or the Cooper-Frye formalism.</li> <li>The file `5-initialConditionCoalescenceNCQ` illustrates the possibility that quarks are in a common velocity field just prior to hadronization via coalescence, leading to baryon/meson grouping of anisotropic flow.&nbsp;</li> <li>The file `6-combined-incoherent-vs-ncq` illustrates the incoherent scenario vs the coalescence scenario without the polar graph for simplicity.</li> <li>The file `7-combined-incoherent-vs-massordering-vs-ncq` illustrates the incoherent scenario, the mass ordering and the coalescence scenarios without the polar graph for simplicity.</li> </ol>