HST Images Reveal Dramatic Changes in the Core of IRC+10216

Abstract

IRC+10216 is the nearest carbon star with a very high mass-loss rate. The existence of a binary companion has been hinted by indirect observational evidence, such as the bipolar morphology of its nebula and a spiral-like pattern in its circumstellar material; however, to date, no companion has been identified. We have examined archival Hubble Space Telescope images of IRC+10216, and find that the images taken in 2011 exhibit dramatic changes in its innermost region from those taken at earlier epochs. The scattered light is more spread out in 2011. After proper motion correction, the brightest peak in 2011 is close to, but not coincident with, the dominant peak in previous epochs. A fainter point-like object was revealed at about 0.5 arcsec from this brightest peak. We suggest that these changes at the core of IRC+10216 are caused by dissipation of intervening circumstellar dust, as indicated by the brightening trend in the lightcurve extracted from the Catalina photometric survey. We tentatively identify the brightest peak in 2011 as the primary star of IRC+10216 and the fainter point-like source as a companion. The cause of non-detections of the companion candidate in earlier epochs is uncertain. These identifications need to be verified by monitoring of the core of IRC+10216 at high resolution in the future.

13 pages, 3 figures, accepted for publication in the Astrophysical Journal Letters

References in corpus (11)

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• Imaging the circumstellar envelopes of AGB stars
• ALMA data suggest the presence of a spiral structure in the inner wind of CW Leo
• Molecular shells in IRC+10216: tracing the mass loss history
• The circumstellar envelope of IRC+10216 from milli-arcsecond to arcmin scales
• Discovery of multiple dust shells beyond 1 arcmin in the circumstellar envelope of IRC+10216 using Herschel/PACS
• Herschel's view into Mira's head
• Radio continuum monitoring of the extreme carbon star IRC+10216
• Surprising detection of an equatorial dust lane on the AGB star IRC+10216
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Cited by in corpus (11)

• The abundance of C2H4 in the circumstellar envelope of IRC+10216
• Magnetic field in IRC+10216 and other C-Rich Evolved Stars
• Investigating Anomalous Photochemistry in the Inner Wind of IRC+10216 Through Interferometric Observations of HC${}_3$N
• Carbon chemistry in IRC+10216: Infrared detection of diacetylene
• Atmospheric molecular blobs shape up circumstellar envelopes of AGB stars
• Monitor variability of millimeter lines in IRC +10216
• Multi-epoch Optical Images of IRC+10216 Tell About the Central Star And the Adjacent Environment
• Evidence for orbital motion of CW Leonis from ground-based astrometry
• The Luminosity Function of Ultra-Faint Trans-Neptunian Objects Detected by JWST
• Charting circumstellar chemistry of carbon-rich asymptotic giant branch stars. II. Abundances and spatial distributions of CS
• Near-infrared Integral-field Spectroscopy of the Wind Forming Region of CW Leo