EAGER: Radiatively Cooled Magnetic Reconnection on Z

Massachusetts Institute Of Technology, Cambridge MA

Investigators

Abstract

This award will support experiments to study radiatively cooled magnetic reconnection, a new frontier of fundamental plasma physics which is important for understanding extreme astrophysical objects. Magnetic reconnection is a ubiquitous process throughout the Universe, which rearranges the topology of the magnetic fields which bind plasmas, and converts magnetic energy to kinetic and thermal energy. In environments with strong radiative cooling, such as around pulsars or in the coronae of black holes, efficient radiative loss may strongly effect the plasma dynamics leading to radiative cooling instabilities. Understanding this radiative collapse process is an outstanding issue in theory, simulation, experiment, and observation of magnetic reconnection under extreme conditions. The experiments supported by this award will use the largest pulsed-power facility in the world, the Z machine at Sandia National Laboratories, to open up a new frontier in fundamental laboratory astrophysics: strongly radiatively cooled magnetic reconnection. Pulsed-power uses intense currents to convert initially solid targets into hot, dense, magnetized plasmas, and a pulsed-power driven reconnection platform has recently been developed. These plasmas are inherently in rough equipartition, with significant contributions to the pressure balance from the magnetic, thermal and kinetic pressures, a situation which occurs in many astrophysical plasmas. The research team will scale this platform from 1 MA peak current, university scale facilities to the Z machine which drives over 25 MA of current. Scaling laws predict 100,000 times stronger radiative cooling on Z than in previous experiments, which will lead to an entirely new and unexplored regime of astrophysically relevant magnetic reconnection studies. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.