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arXiv · 2605.15489

GeV {\gamma}-ray emission in the low-mass star-forming region AFGL 490

Li-Nuo Yang·Sheng Tang·Pak-Hin Thomas Tam
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Abstract

We report the discovery of an extended GeV {\gamma}-ray source, 4FGL J0330.7+5845e, associated with the star-forming region AFGL 490 using 17 years of Fermi-LAT data. The emission is spatially coincident with a dense molecular cloud and centered near the massive protostar AFGL 490. Its spectral energy distribution shows a distinct high-energy cutoff. Both leptonic and hadronic models can fit the {\gamma}-ray spectrum, but energetic arguments rule out stellar winds as the primary accelerator. Instead, the protostellar jet driven by AFGL 490 is identified as a plausible site for particle acceleration, and the derived timescales and maximum particle energies are consistent with theoretical predictions for such jets.

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Li-Nuo Yang, Sheng Tang, Pak-Hin Thomas Tam. 2026-05-15. GeV {\gamma}-ray emission in the low-mass star-forming region AFGL 490. https://arxiv.org/abs/2605.15489

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