  The head-on collision between electrostatic shocks is studied via
multi-dimensional Particle-In-Cell simulations. It is found that the shock
velocities drop significantly and a strong magnetic field is generated after
the interaction. This transverse magnetic field is due to the Weibel
instability caused by pressure anisotropies due to longitudinal electron
heating while the shocks approach each other. Finally, it is shown that this
phenomenon can be explored in the laboratory with current laser facilities
within a significant parameter range.
