Nested Dust Shells around the Wolf-Rayet Binary WR 140 observed with JWST
Abstract
Massive colliding-wind binaries that host a Wolf-Rayet (WR) star present a potentially important source of dust and chemical enrichment in the interstellar medium (ISM). However, the chemical composition and survival of dust formed from such systems is not well understood. The carbon-rich WR (WC) binary WR~140 presents an ideal astrophysical laboratory for investigating these questions given its well-defined orbital period and predictable dust-formation episodes every 7.93 years around periastron passage. We present observations from our Early Release Science program (ERS1349) with the James Webb Space Telescope (JWST) Mid-Infrared Instrument (MIRI) Medium-Resolution Spectrometer (MRS) and Imager that reveal the spectral and spatial signatures of nested circumstellar dust shells around WR~140. MIRI MRS spectroscopy of the second dust shell and Imager detections of over 17 shells formed throughout the past years confirm the survival of carbonaceous dust grains from WR~140 that are likely carriers of "unidentified infrared" (UIR)-band features at 6.4 and 7.7 m. The observations indicate that dust-forming WC binaries can enrich the ISM with organic compounds and carbonaceous dust.
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Cite
@article{arxiv.2210.06452,
title = {Nested Dust Shells around the Wolf-Rayet Binary WR 140 observed with JWST},
author = {Ryan M. Lau and Matthew J. Hankins and Yinuo Han and Ioannis Argyriou and Michael F. Corcoran and Jan J. Eldridge and Izumi Endo and Ori D. Fox and Macarena Garcia Marin and Theodore R. Gull and Olivia C. Jones and Kenji Hamaguchi and Astrid Lamberts and David R. Law and Thomas Madura and Sergey V. Marchenko and Hideo Matsuhara and Anthony F. J. Moffat and Mark R. Morris and Patrick W. Morris and Takashi Onaka and Michael E. Ressler and Noel D. Richardson and Christopher M. P. Russell and Joel Sanchez-Bermudez and Nathan Smith and Anthony Soulain and Ian R. Stevens and Peter Tuthill and Gerd Weigelt and Peredur M. Williams and Ryodai Yamaguchi},
journal= {arXiv preprint arXiv:2210.06452},
year = {2022}
}
Comments
Published in Nature Astronomy on Oct 12, 2022; 21 pages, 5 figures, 2 tables