Multi-line Observations, Models, and Data Needed to Understand the Nature of UV-irradiated Interstellar Matter

Abstract

Far-ultraviolet photons from OB-type massive stars regulate the heating, ionization, and chemistry of much of the neutral interstellar gas in star-forming galaxies. The interaction of FUV radiation and interstellar matter takes place in environments broadly known as photodissociation regions (PDRs). PDR line diagnostics are the smoking gun of the radiative feedback from massive stars. Improving our understanding of stellar feedback in the ISM requires quantifying the energy budget, gas dynamics, and chemical composition of PDR environments. This goal demands astronomical instrumentation able to deliver multi-line spectroscopic images of the ISM (of the Milky Way and nearby galaxies). It also requires interdisciplinary collaborations to obtain the rate coefficients and cross sections of the many microphysical processes that occur in the ISM and that are included in models such as the Meudon PDR code.

To appear in "The European Physical Journal Web of Conferences". Invited paper at "Multi-line Diagnostics of the Interstellar Medium", Nice 2022

References in corpus (17)

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• The anatomy of the Orion B Giant Molecular Cloud: A local template for studies of nearby galaxies
• Photodissociation and X-Ray Dominated Regions
• Compression and ablation of the photo-irradiated cloud the Orion Bar
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• The penetration of FUV radiation into molecular clouds
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• Complex organic molecules in strongly UV-irradiated gas
• Trans-cis molecular photoswitching in interstellar Space
• On the chemistry and distribution of HOC+ in M82: More evidence for extensive PDRs
• Bottlenecks to interstellar sulfur chemistry: Sulfur-bearing hydrides in UV-illuminated gas and grains
• The initial gas-phase sulfur abundance in the Orion Molecular Cloud from sulfur radio recombination lines
• Direct estimation of electron density in the Orion Bar PDR from mm-wave carbon recombination lines
• Dynamical effects of the radiative stellar feedback on the H I-to-H2 transition

Cited by in corpus (1)

• The extremely sharp transition between molecular and ionized gas in the Horsehead nebula