Collisionless shocks, How shocking!

  • Date: –15:00
  • Location: Ångströmlaboratoriet, Lägerhyddsvägen 1 Hjorter's room (Å73101)
  • Lecturer: Ahmad Lalti, Institute for Space Physics, Uppsala University, Sweden
  • Organiser: Division of Astronomy and Space Physics, Department of Physics and Astronomy
  • Contact person: Sofia Ramstedt
  • Seminarium

4 month seminar

Collisions in hydrodynamic fluids is the main mechanism that allow shock waves to transform the bulk kinetic energy of the incoming flow into heat, and by doing so increase the entropy of the system. When going into space plasmas, one is faced with a dilemma. How could a plasma, as the solar wind, which has a collisional mean free path of the order of AUs allow for the evolution of such structures? Scientists have been exploring the dynamics of collisionless shocks since the 1950s. And one major mechanism proposed to replace collisions is wave-particle interactions. This PhD project goal is to advance our understanding of the dynamics and evolution of collisionless shocks, by using in-situ measurements from Magnetospheric MultiScale (MMS) spacecraft. We present the initial results of our first investigations concerning  the effect of one type of plasma waves, whistler waves, on plasma thermalization in collisionless shocks.