Stability and Energy-Casimir Mapping for Integrable Deformations of the Kermack-McKendrick System

<div>The images of the equilibrium points <svg height="11.5564pt" id="M291" style="vertical-align:-2.26807pt" version="1.1" viewbox="-0.0498162 -9.28833 44.7002 11.5564" width="44.7002pt" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink"><g transform="matrix(.013,0,0,-0.013,0,0)"><path d="M300 -147C201 -63 143 98 143 270S200 602 300 686L282 710C136 610 70 450 70 271V270C70 89 136 -72 282 -170L300 -147Z" id="g113-41"></path></g><g transform="matrix(.013,0,0,-0.013,4.498,0)"><path d="M822 650H589L583 622C660 617 677 607 674 561C672 534 664 481 647 390L600 137H596L273 650H126L120 622C176 620 194 615 207 594C221 571 225 557 214 504L161 257C141 166 129 112 121 85C108 42 83 30 29 28L23 0H260L266 28C193 33 173 42 176 89C178 122 186 172 202 255L256 527H259L583 -8H612L690 390C708 481 720 535 728 558C744 603 756 619 816 622L822 650Z" id="g113-79"></path></g><g transform="matrix(.013,0,0,-0.013,15.408,0)"><path d="M95 130C70 130 46 113 46 88C46 72 54 64 59 64C93 55 121 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Advances in Mathematical Physics

fig3

Figure 3

Figure 3: Stability and Energy-Casimir Mapping for Integrable Deformations of the Kermack-McKendrick System 