WR DustERS - Decoding Smoke Signals in the Glare of Wolf Rayet Stars with JWST

JWST Director's Discretionary Early Release Science Program 1349

Welcome to the WR DustERS Webpage

Latest Major Update (Oct 12, 2022). We have published initial results from our MIRI Imager and MRS observations of WR140 in Nature Astronomy. The MIRI observations reveal the presence of more than 17 circumstellar dust shells around WR140 formed by the binary system over the past ~130 years, and the spectroscopic signatures of the circumstellar dust is consistent with "Unidentified Infrared Band" features. Our results indicate that dust-forming carbon-rich WR binaries like WR140 are enriching the interstellar medium with carbon-rich aromatic compounds and carbonaceous dust.

On the same day, results from high-resolution ground-based infrared imaging were published in Nature by WR DustERS science collaborator Yinuo Han. Geometric models of WR140's dust emission from Han et al. (2022) were used to interpret the >17 circumstellar dust shells revealed by JWST.

Background. Dust is a key ingredient in the formation of stars and planets. However, the dominant channels of dust production throughout cosmic time are still unclear. With its unprecedented sensitivity and spatial resolution in the mid-IR, JWST is the ideal platform to address this issue by investigating the dust abundance, composition, and production rates of various dusty sources. In particular, colliding-wind Wolf-Rayet (WR) binaries are efficient dust producers in the local Universe, and likely existed in the earliest galaxies. To study these interesting objects, have conducted JWST observations of the colliding-wind binaries WR140 and WR137 to study WR dust composition, abundance, and formation mechanisms.

In our ERS program (ERS 1349 - WR DustERS), we utilized three key JWST observing modes:

  • The Medium-Resolution Spectrometer (MRS) on the Mid-Infrared Instrument (MIRI)
  • The Imager on the Mid-Infrared Instrument (MIRI)
  • Aperture Masking Interferometry (AMI) mode with the Near Infrared Imager and Slitless Spectrograph (NIRISS)

Our observations will establish a benchmark for key observing modes for imaging bright sources with faint extended emission. This will be valuable in various astrophysical contexts including mass-loss from evolved stars, dusty tori around active galactic nuclei, and protoplanetary disks. We are committed to designing and delivering science-enabling products for the JWST community that address technical issues such as bright source artifacts that will limit the maximum achievable image contrast.

Contact. For any questions or inquiries, please contact Ryan Lau (ryan.lau_at_noirlab.edu)