Three-dimensional visualization and modeling of large-area, nanoscale topography measurements

High-resolution nanometrology is a critical area of development for nanoscale manufacturing, especially as it affects production throughput and fabrication quality. Similarly, large area nanometrology is an emerging topic of interest particularly as demand rises for flexible electronics and large area microdevices. Atomic force microscopy (AFM) is one of the most popular tools for nanometrology, and high-resolution AFM scanning often requires a significant time commitment and often produces datasets of several million points. In large area AFM there is additional error introduced by long-range stage movements, and for larger datasets this presents challenges during analysis. It is therefore critical for the development of data processing techniques to keep pace with the requirements of analyzing this type of data, and for these techniques to be portable as miniaturization in AFM is becoming more common. This work presents a data fitting algorithm designed for reducing the parameters of large-area data sets, written in python, and utilizing well-established spline fitting techniques. This algorithm can reduce the number of parameters for a dataset by more than 90%, smooths vibrational noise, and simplifies visual analysis. The results of this work augment the current nanometrology analysis programs and will potentially drive forward the expansion of very large-area AFM to broader usage.Mechanical Engineerin

A Hot Saturn Orbiting an Oscillating Late Subgiant Discovered by TESS

© 2019. The American Astronomical Society. All rights reserved.. We present the discovery of HD 221416 b, the first transiting planet identified by the Transiting Exoplanet Survey Satellite (TESS) for which asteroseismology of the host star is possible. HD 221416 b (HIP 116158, TOI-197) is a bright (V = 8.2 mag), spectroscopically classified subgiant that oscillates with an average frequency of about 430 μHz and displays a clear signature of mixed modes. The oscillation amplitude confirms that the redder TESS bandpass compared to Kepler has a small effect on the oscillations, supporting the expected yield of thousands of solar-like oscillators with TESS 2 minute cadence observations. Asteroseismic modeling yields a robust determination of the host star radius (R∗ = 2.943 ± 0.064 Ro), mass (M∗ = 1.212 ± 0.074 Mo), and age (4.9 ± 1.1 Gyr), and demonstrates that it has just started ascending the red-giant branch. Combining asteroseismology with transit modeling and radial-velocity observations, we show that the planet is a "hot Saturn" (Rp = 9.17 ± 0.33 R⊕) with an orbital period of ∼14.3 days, irradiance of F = 343 ± 24 F⊕, and moderate mass (Mp = 60.5 ± 5.7 M⊕) and density (ρp = 0.431 ± 0.062 g cm-3). The properties of HD 221416 b show that the host-star metallicity-planet mass correlation found in sub-Saturns (4-8 R⊕) does not extend to larger radii, indicating that planets in the transition between sub-Saturns and Jupiters follow a relatively narrow range of densities. With a density measured to ∼15%, HD 221416 b is one of the best characterized Saturn-size planets to date, augmenting the small number of known transiting planets around evolved stars and demonstrating the power of TESS to characterize exoplanets and their host stars using asteroseismology