\(QS11_{6}^{(2)}\)
Description
Topological configuration of singularities: \(s,s,a,a;N,(0,2)SN\)
Phase Portrait
Topological Invariants
| TCSP | Fin Sep | Inf Sep |
| \(11\) | \(4422\) | \(2121\) |
Example
The quadratic differential system
\[\begin{cases} \dot{x} = P_x(x,y) \\ \dot{y} = P_y(x,y) \end{cases}\]
has the following phase portrait done with P4.
The phase portrait appears in the following papers
- With name \(BD35\) in {J. C. Artés}, Systems of class BD, {Preprint} (2026).
- With name \(26\) in {A. Ferragut, J. D. García-Saldaña and C. Valls}, Phase portraits of Abel quadratic differential systems of second kind with symmetries, Dyn. Syst. { bf 34} (2019), no.~2, 301--333; MR3941199
- With name \(Fig 27 P6O\) in {A. M. Travaglini}, Integrability and geometryof quadratic differential systems with invariant hyperbolas, {Ph. D., Uni. de Sao Paulo} (2026).
- With name \(Fig. 4 06\) in {P. C. Carri\~ao, M. E. S. Gomes and A. A. G. Ruas}, Planar quadratic vector fields with finite saddle connection on a straight line (convex case), Qual. Theory Dyn. Syst. { bf 6} (2005), no.~2, 187--204; MR2420856