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Context. Parker Solar Probe (PSP) performs Venus gravity assists (VGAs) in order to lower its perihelion. PSP takes high-cadence electric and magnetic field observations during these VGAs, providing the opportunity to study plasma waves in Venus’s induced magnetosphere. Aims. We summarize the plasma environment during these VGAs, including the regions of near-Venus space that PSP traversed and the key boundary crossings. We comprehensively identify Langmuir, ion acoustic, whistler-mode, and ion cyclotron waves during these VGAs and map the location of these waves throughout near-Venus space. Methods. This study analyzes different data products from the PSP FIELDS instrument suite from throughout the first five VGAs. Results. We compare the FIELDS instrumentation capabilities to the capabilities of the plasma wave instruments on board the Pioneer Venus Orbiter (PVO) and the Venus Express (VEX). We find that the PVO electric field instrument was well suited to observe Langmuir waves, especially near the bow shock and in the foreshock. However, evaluation of the other plasma waves detected by PSP FIELDS reveals that PVO and VEX would have often been unable to observe key features of these waves modes, including maximum power, bandwidth, and propagation direction. These wave characteristics provide critical information on the wave generation mechanisms and wave-particle interactions, so provide fundamental information on the nature of Venus’s induced magnetosphere. Conclusions. These results highlight the advances in plasma wave instrumentation capabilities that have been made in the decades since the PVO and VEX eras, and illustrate the value of a plasma wave instrument on a new Venus mission. 

We have designed a new filter pack array to measure angular variations in x-ray spectra during a single shot. The filter pack was composed of repeating identical columns of aluminum and copper filters of varying thicknesses. These columns were located at different positions to measure the spectrum at each corresponding angle. This array was utilized in an experiment to measure the energy evolution of betatron x rays in a laser wakefield accelerator by curving the wakefield with a transverse density gradient, streaking the x rays across the array in front of an x-ray charge-coupled device (CCD) camera. After subtracting the background and “flattening” the image to remove spatial nonuniformities, a critical energy was calculated for each position that produced the best agreement with the measured signal. There was a clear change in critical energy with angle, shedding light on the dynamics of the electrons that traveled through the accelerator. These angles correspond to distinct emission times, covering a timescale of tens of picoseconds. The filter pack was capable of recovering these angular details without the impact of errors introduced by shot-to-shot variability. 

Conference presentation at the annual Allied Social Sciences Conference in San Antonio, Jan 2024 

Student focusing and noticing, which drive reasoning, are important but under researched aspects of student learning. Quadratic functions representations are perceptually and conceptually complex and thus, offer much for students to focus on and notice. Our study compared a teacher’s goals for student focusing and noticing during quadratic functions instruction with what students actually focused on and noticed. Qualitative analysis revealed some alignment but also informative ways that the teacher’s goals and student outcomes for focusing and noticing were misaligned. These results will further the field’s understanding of how students learn about quadratic functions and may have implications for student focusing and noticing of other mathematics topics as well.