[Galaxies SIG] The Case for a FUV Spectrograph: From Molecular ISM to Hot IGM - Blakesley Burkhart скачать в хорошем качестве

[Galaxies SIG] The Case for a FUV Spectrograph: From Molecular ISM to Hot IGM - Blakesley Burkhart

Galaxies SIG Seminar on Tuesday, 5 December 2023 The Case for a High-resolution FUV Spectrograph: From the Molecular Galactic ISM to the Hot IGM In this talk, I will highlight two areas in gaseous astrophysics where exciting mysteries could be addressed with a high-resolution (R greater than 10, 000) FUV spectrograph. First, I will discuss how the low redshift (z ~0.1) Lyman-α forest observations (requiring space-based FUV with R greater than 10000) have challenged the most advanced cosmological simulations and defy physical arguments that work well at z greater than 2, as the amount of neutral hydrogen predicted is far larger in simulations than what is observed. I will show how including active black hole feedback can reconcile the amount of neutral gas by providing extra heating. These findings herald a significant paradigm shift for cosmological simulations and observations that target the low redshift IGM, however, more data is needed to disentangle the models. Second, I will zoom back to the local ISM, where a large FoV R greater than 10,000 FUV spectrograph could reveal molecular H2 in emission via the H2 fluorescent excitation lines. Such observations could illuminate molecular cloud lifecycles and uncover the origins of mysterious structures in our Galaxy.