Enhancement of Quasistationary Shocks and Heating via Temporal Staging in a Magnetized Laser-Plasma Jet

Suppressing the false magnetic field in beam-splitting Faraday rotation measurement

In laser-plasma experiments, the beam-splitting Faraday rotation measurement is usually used for mapping the magnetic field. Due to the geometric characteristics of the beam-splitting configuration, the split beams are not always incident normally on the image plane, and their spots have different shapes and intensity distributions. Ignoring these issues will inevitably introduce errors in polarization calculation and then generate large false magnetic fields. We introduced the restoration method to recover the spots and suppress the false magnetic field. We applied this method to ZEMAX simulation data and Shenguang-II experimental data. Compared to the method of directly overlaying the spots, it can reduce the average false magnetic field by about 50%. And the false magnetic field at the edge of the spot is reduced by one order of magnitude. We can highly improve the accuracy of the magnetic field measurement with the Faraday rotation method.

A Martin-Puplett interferometer (MPI) optical polarimeter: Design and laboratory tests

Spontaneous and external magnetic fields interacting with plasmas are essential in high-energy-density and magnetic confinement fusion physics. Measuring these magnetic fields, especially their topologies, is crucial. This paper develops a new type of optical polarimeter based on the Martin-Puplett interferometer (MPI), which can probe magnetic fields with the Faraday rotation method. We introduce the design and working principle of an MPI polarimeter. With the laboratory tests, we demonstrate the measurement process and compare the results with the measurement result of a Gauss meter. These very close results verify the polarization detection capability of the MPI polarimeter and show the potential for its application in magnetic field measurement.

X-ray Self-Emission Imaging of Hydrodynamic Laser-Induced Astrophysical Phenomena

In this article, we present an overview of the application of X-ray self-emission methods for the imaging of hydrodynamic astrophysical phenomena in laboratory-scale experiments. Typical diagnostic approaches, their advantages, drawbacks, and application perspectives are considered. We show that X-ray imaging and spectroscopy methods with 2D and even 1D spatial resolution are valuable for numerous laboratory astrophysical problems. Furthermore, the methods revealed the hydrodynamic evolution, the spatial shape and structure, and spatial features of important parameters such as electron density and plasma temperature of astrophysical objects and related phenomena, which are also required for the verification of astrophysical models.