The most massive stars in the Arches cluster

Understand

We study a sample composed of 28 of the brightest stars in the Arches cluster.

• We analyze K-band spectra obtained with the integral field spectrograph SINFONI on the VLT.
• Atmosphere models computed with the code CMFGEN are used to derive the effective temperatures, luminosities, stellar abundances, mass loss rates and wind terminal velocities.
• We find that the stars in our sample are either H-rich WN7-9 stars (WN7-9h) or O supergiants, two being classified as OIf+.