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arXiv · 2210.01453

Massive stars in metal-poor dwarf galaxies are often extreme rotators

Abel Schootemeijer·Danny J. Lennon·Miriam Garcia·Norbert Langer·Ben Hastings·Christoph Schürmann
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Abstract

We probe how common extremely rapid rotation is among massive stars in the early universe by measuring the OBe star fraction in nearby metal-poor dwarf galaxies. We apply a new method that uses broad-band photometry to measure the galaxy-wide OBe star fractions in the Magellanic Clouds and three more distant, more metal-poor dwarf galaxies. We find OBe star fractions of ~20% in the Large Magellanic Cloud (0.5 Z_Solar), and ~30% in the Small Magellanic Cloud (0.2 Z_Solar) as well as in the so-far unexplored metallicity range from 0.1 Z_solar to 0.2 Z_solar occupied by the other three dwarf galaxies. Our results imply that extremely rapid rotation is common among massive stars in metal-poor environments such as the early universe.

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Abel Schootemeijer, Danny J. Lennon, Miriam Garcia, Norbert Langer, Ben Hastings, Christoph Schürmann. 2022-10-04. Massive stars in metal-poor dwarf galaxies are often extreme rotators. https://doi.org/10.1017/s1743921322002538

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