Abstract

Contributed Talk - Splinter LowMet

Friday, 13 September 2024, 17:05   (S23)

Accretion Disks or Infalling Envelopes? Insights into High-Mass Star Formation in the LMC

Roya Hamedani Golshan, Anna McLeod, Alvaro Sannchez-Monge, Marta Sewilo, Peter Schilke
University of Cologne, Durham University, Universitat Autònoma de Barcelona, Godard Space Center and University of Maryland, University of Cologne

The sites of star formation in the Large Magellanic Cloud (LMC) can be pinpointed with unprecedented spatial resolution down to a few thousand AU using ALMA. In our ALMA survey of 20 massive star-forming regions (with a resolution of ~0.1 pc) within the LMC, we investigate how sub-solar metallicity influences the star formation process. This poster focuses on our detection of butterfly-shaped emission patterns in Position-Velocity (PV) diagrams of the dense gas tracer CS (5-4), associated with compact 1.2 mm continuum cores and in directions perpendicular to detected outflows. The butterfly shape in the PV diagrams typically suggests rotational motion, with enhanced velocities near the center. The first toroid feeding an accreting disk in the LMC has been unexpectedly detected around an optically bright massive young star, highlighting the impact of a lower metallicity environment (McLeod et al., 2024). Additionally, infrared studies in the outer Galaxy report fewer disk fractions, suggesting that reduced metallicity leads to shorter accretion timescales (Patra et al., 2024). Our ALMA observations provide a unique inventory of accreting disk candidates in the sub-solar metallicity environment of the LMC. Distinguishing between accreting disks and infalling envelopes will require follow-up observations with higher spatial and spectral resolution in the mm regime, as well as infrared.