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arXiv · 2412.01194

Nuclear de-excitation line emissions from giant molecular clouds

Zhaodong Shi·Bing Liu·Rui-zhi Yang
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Abstract

Understanding how cosmic rays (CRs) propagate within the giant molecular clouds (GMCs) is critical for studying the dynamics and chemical processes inside the clouds. The flux of low-energy CRs inside the dense cores of GMCs strongly affects the heating and ionization of the gases and further influences the star-forming process. We analytically calculated the CR distribution inside GMCs assuming different diffusion coefficients, and estimated the corresponding nuclear de-excitation line emission and the ionization rate resulting from the interaction between the penetrating CRs and gases. We find that future MeV observations can be used as a unique probe to measure the low-energy CR density in situ and test different CR propagation scenario inside GMCs.

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Zhaodong Shi, Bing Liu, Rui-zhi Yang. 2024-12-02. Nuclear de-excitation line emissions from giant molecular clouds. https://doi.org/10.1051/0004-6361%2F202451973

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