Evolutionary map of the universe: Detection of the Wolf-Rayet star WR40
We present a radio-continuum detection of the well-known Wolf-Rayet star WR40 at 943.5MHz using observations from the Evolutionary Map of the Universe (EMU) survey. We find that the shell surrounding WR40, known as RCW 58, has a flux density of 158.9?15.8 mJy and the star itself is 0.41?0.04 mJy. The shell size is found to be 9?x 6?, which matches well with the shell in H? and is similarly matched to the shell at 22 ?m in infrared. Using Gaia data, we derive a linear size of 7:32(?0:34) x 4:89(?0:23) pc at a distance of 2.79?0.13 kpc. We use the previous Australia Telescope Compact Array (ATCA) observations at 8.64, 4.80, and 2.4GHz to determine a spectral index of WR40, which is estimated to be ? = 0:80?0:11, indicating that the emission from the star is thermal.
Authors
- Andrew Hopkins (ORCID: https://orcid.org/0000-0002-6097-2747)
- Miroslav D Filipović (ORCID: https://orcid.org/0000-0002-4990-9288)
- J. D. Collier (ORCID: https://orcid.org/0000-0002-2326-7432)
- R. Z. E. Alsaberi (ORCID: https://orcid.org/0000-0001-5609-7372)
- Yjan Gordon (ORCID: https://orcid.org/0000-0003-1432-253X)
- N. F. H. Tothill (ORCID: https://orcid.org/0000-0002-9931-5162)
- Andy Bradley (ORCID: https://orcid.org/0009-0007-4802-2793)
- Zachary J. Smeaton (ORCID: https://orcid.org/0009-0009-7061-0553)
- H. Zakir (ORCID: https://orcid.org/0009-0006-4391-3880)
Institutions
- University of Wisconsin–Madison (US)
- International Centre for Radio Astronomy Research (AU)
- Gifu University (JP)
- Western Sydney University (AU)
- Macquarie University (AU)
Publication Details
- Journal
- Serbian Astronomical Journal
- Published
- 2025-01-01
- DOI
- https://doi.org/10.2298/saj250529001b
- Primary Topic
- Astronomy and Astrophysical Research
- Type
- article
- Field-Weighted Citation Impact
- 0.00
Funders
- Australian Government
- European Space Agency
- Commonwealth Scientific and Industrial Research Organisation
- Government of Western Australia