UCLA

Collisionless shocks are a common phenomena that occur in astrophysical and terrestrial space environments with a wide variety of physical characteristics, but are generally preformed, steady state when observed. This thesis studies the transient state that leads to the formation of a dissipation dominated, quasi-perpendicular, subcritical collisionless shock. To achieve this, two experimental platforms were conceived: (1) utilizing the Large Plasma Device (LaPD) at the University of California, Los Angeles (UCLA) to produce a magnetized ambient-plasma and the Phoenix Laser System to create an expanding debris-plasma to shock the ambient-plasma and (2) installing a large (56 cm diameter) pulsed Helmholtz Coil (Bo < 1.25 kG) into the target chamber at the Trident Laser Facility at Los Alamos National Laboratory (LANL) in which the ambient- and debris-plasma were created with two consecutive laser pulses. As the debris-plasma expands through the magnetized ambient-plasma a diamagnetic cavity is formed that expels the enclosed magnetic field and compresses the field upstream, outside the cavity. The formed magnetic compression acts as a piston to energize and shock the ambient-plasma, when conditions are suitable. The goal of this dissertation is to produce, identify, and quantify the magnetic characteristics associated with coupling of energy and momentum from a Laser-Produced Plasma (debris-plasma) into a magnetized ambient-plasma with the use of the driven magnetic piston.