The First Optical Spectra of Wolf Rayet Stars in M101 Revealed with Gemini/GMOS

نویسندگان

  • J. L. Pledger
  • M. M. Shara
  • M. Wilde
  • P. A. Crowther
  • D. Zurek
  • A.F.J. Moffat
چکیده

Deep narrow-band HST imaging of the iconic spiral galaxy M101 has revealed over a thousand new Wolf Rayet (WR) candidates. We report spectrographic confirmation of 10 He iiemission line sources hosting 15 WR stars. We find WR stars present at both sub– and super– solar metalicities with WC stars favouring more metal-rich regions compared to WN stars. We investigate the association of WR stars with H ii regions using archival HST imaging and conclude that the majority of WR stars are in or associated with H ii regions. Of the 10 emission lines sources, only one appears to be unassociated with a star-forming region. Our spectroscopic survey provides confidence that our narrow-band photometric candidates are in fact bonafide WR stars, which will allow us to characterise the progenitors of any core-collapse supernovae that erupt in the future in M101.

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تاریخ انتشار 2017