Isolated Wolf-Rayet Stars and O Supergiants in the Galactic Center Region Identified via Paschen-alpha Excess

Understand

We report the discovery of 19 hot, evolved, massive stars near the Galactic center region (GCR).

• These objects were selected for spectroscopy owing to their detection as strong sources of Paschen-alpha emission-line excess, following a narrowband imaging survey of the central 0.65 x 0.25 degress (l, b) around Sgr A* with the Hubble Space Telescope.
• Discoveries include 5 carbon-type (WC) and 6 nitrogen-type (WN) Wolf-Rayet stars, 6 O supergiants, and 2 B supergiants.
• Two of the O supergiants have X-ray counterparts, the properties of which are broadly consistent with colliding-wind binaries and solitary O stars.