Hostname: page-component-cd9895bd7-jkksz Total loading time: 0 Render date: 2024-12-25T16:02:25.688Z Has data issue: false hasContentIssue false

A Resolved Millimeter Emission Belt in the AU Mic Debris Disk

Published online by Cambridge University Press:  06 January 2014

Meredith MacGregor*
Affiliation:
Harvard-Smithsonian Center for Astrophyics60 Garden St., MS-10, Cambridge, MA 02138 email: [email protected]
Rights & Permissions [Opens in a new window]

Abstract

Core share and HTML view are not available for this content. However, as you have access to this content, a full PDF is available via the ‘Save PDF’ action button.

Imaging debris disks at millimeter wavelengths is important, because emission at these long wavelengths is dominated by large grains with dynamics similar to the population of dust-producing planetesimals. We have used the SMA and ALMA to make 1.3 millimeter observations of the debris disk surrounding the nearby (9.9 pc), ~10 Myr-old, M-type flare star AU Microscopii. We characterize the disk by implementing Markov Chain Monte Carlo methods to fit parametric models to the visibilities. The millimeter observations reveal a belt of dust emission that peaks at a radius of 40 AU. This outer size scale agrees with predictions for a reservoir of planetesimals (a “birth ring”) based on the shape of the midplane scattered light profile. We do not find any significant asymmetries in the structure or the centroid position of the emission belt. The ALMA observations with a resolution of 0.6 arcsec (6 AU) also reveal a previously unknown central emission peak, ~6 times brighter than the stellar photosphere at these wavelengths. This central component remains unresolved and could be explained by stellar activity or an inner planetesimal belt located ≲3 AU from the star and containing roughly 1% the mass of the outer belt. Future observations with higher angular resolution will be able to distinguish between these possibilities.

Type
Contributed Papers
Copyright
Copyright © International Astronomical Union 2013 

References

Augereau, J.-C. & Beust, H. 2006, A&A, 455, 987Google Scholar
Augereau, J.-C., Nelson, R. P., Lagrange, A. M., Papaloizou, J. C. B., & Mouillet, D. 2001, A&A, 370, 447Google Scholar
Bower, G. C., Bolatto, A., Ford, E. B., & Kalas, P. 2009 ApJ, 701, 1922CrossRefGoogle Scholar
Cranmer, S. R., Wilner, D. J., & MacGregor, M. A. 2013, ApJ, 772, 149CrossRefGoogle Scholar
Hauschildt, P. H., Allard, F., & Baron, E. 1999 ApJ, 512, 377CrossRefGoogle Scholar
Kalas, P., Liu, M. C., & Matthews, B. C. 2004, Science, 303, 1990CrossRefGoogle Scholar
Kennedy, G. M. & Wyatt, M. C. 2010, MNRAS, 405, 1253Google Scholar
Kuchner, M. J. & Stark, C. C. 2010, ApJ, 140, 1007CrossRefGoogle Scholar
Liu, M. C. 2004, Science, 305, 1442CrossRefGoogle ScholarPubMed
MacGregor, M. A., Wilner, D. J., Rosenfeld, K. A., Andrews, S. M., Matthews, B., Hughes, A. M., Booth, M., Chiang, E., Graham, J. R., Kalas, P., Kennedy, G., Sibthorpe, B. 2013, ApJ, 762, L21CrossRefGoogle Scholar
Strubbe, L. E. & Chiang, E. I. 2006, ApJ, 648, 652Google Scholar
Wilner, D. J., Andrews, S. M., MacGregor, M. A., & Hughes, A. M. 2012, ApJ, 749, L27CrossRefGoogle Scholar
Zuckerman, B., Song, I., Bessell, M. S., & Webb, R. A. 2001, ApJ, 562, L87CrossRefGoogle Scholar