Determining ideal grating parameters for UV blazed gratings

Ultraviolet (UV, 900-2000 angstrom) spectroscopy simultaneously traces the most common elements (e.g., H, He, O, C, N) in many phases, in the form of ionic, atomic, and molecular lines. UV grating spectrometers hence offer unique insights into astrophysical systems and the impacts of their evolution. This work seeks to understand how we might best optimize certain grating designs for targeted astrophysical tracers. Our work is intended to guide proposers in determining the ideal grating parameters given their specific science objectives. We report on the results of the initial phase of the project, a thorough design phase to determine the ideal grating parameters and electron-beam lithography/potassium hydroxide patterning prescriptions for blazed UV gratings. We use grating simulation software to explore a grating-parameter space and determine the key performance expectations for gratings in next-generation UV space instruments. We present our results for a rough grid in grating-parameter space (blaze angle: similar to 30 degrees-76 degrees, grating period: 100-5000 nm). Future work will explore specific cases that include the nominal grating prescriptions for current (e.g., Hyperion, PolStar, LUVOIR) and future mission designs.

Automated summary

This work focuses on optimizing grating designs for targeted astrophysical tracers, aiming to provide valuable insights for future UV space instruments. It presents the results of the initial phase, exploring the ideal grating parameters and patterns for blazed UV gratings, and outlines future research plans for specific mission designs.