Artículo de revista
Resolving the core of R136 in the optical
Fecha
2022Registro en:
The Astrophysical Journal, 935:162 (11pp), 2022 August 20
10.3847/1538-4357/ac8424
Autor
Kalari, Venu
Horch, Elliott P.
Salinas, Ricardo
Vink, Jorick S.
Andersen, Morten
Bestenlehner, Joachim M.
Rubio López, Mónica Solange
Institución
Resumen
The sharpest optical images of the R136 cluster in the Large Magellanic Cloud are presented, allowing us for the first
time to resolve members of the central core, including R136a1, the most-massive star known. These data were taken
using the Gemini speckle imager Zorro in medium-band filters with effective wavelengths similar to BVRI achieving
angular resolutions between 30–40 mas. All stars previously known in the literature, having V <16 mag within the
central 2″×2″, were recovered. Visual companions ( 40mas; 2000 au) were detected for the WN5h stars R136 a1
and a3. Photometry of the visual companion of a1 suggests it is of mid-O spectral type. Based on new photometric
luminosities using the resolved Zorro imaging, the masses of the individual WN5h stars are estimated to be between
150 and 200Me, lowering significantly the present-day masses of some of the most-massive stars known. These
mass estimates are critical anchor points for establishing the stellar upper-mass function.