Publication Date:
2020-05-11
Description:
We present simulations of a 500 pc2 region, containing gas of mass 4 × 106 M⊙, extracted from an entire spiral galaxy simulation, scaled up in resolution, including photoionising feedback from stars of mass 〉 18 M⊙. Our region is evolved for 10 Myr and shows clustered star formation along the arm generating ≈ 5000 cluster sink particles ≈ 5% of which contain at least one of the ≈ 4000 stars of mass 〉 18 M⊙. Photoionisation has a noticeable effect on the gas in the region, producing ionised cavities and leading to dense features at the edge of the HII regions. Compared to the no-feedback case, Photoionisation produces a larger total mass of clouds and clumps, with around twice as many such objects, which are individually smaller and more broken up. After this we see a rapid decrease in the total mass in clouds and the number of clouds. Unlike studies of isolated clouds, our simulations follow the long range effects of ionisation, with some already-dense gas, becoming compressed from multiple sides by neighbouring HII regions. This causes star formation that is both accelerated and partially displaced throughout the spiral arm with up to 30% of our cluster sink particle mass forming at distances 〉 5 pc from sites of sink formation in the absence of feedback. At later times, the star formation rate decreases to below that of the no-feedback case.
Print ISSN:
0035-8711
Electronic ISSN:
1365-2966
Topics:
Physics
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