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Title: The Inner 25 au Debris Distribution in the ϵ Eri System

Abstract

Debris disk morphology is wavelength dependent due to the wide range of particle sizes and size-dependent dynamics influenced by various forces. Resolved images of nearby debris disks reveal complex disk structures that are difficult to distinguish from their spectral energy distributions. Therefore, multi-wavelength resolved images of nearby debris systems provide an essential foundation to understand the intricate interplay between collisional, gravitational, and radiative forces that govern debris disk structures. We present the Stratospheric Observatory for Infrared Astronomy (SOFIA) 35 μ m resolved disk image of ϵ Eri, the closest debris disk around a star similar to the early Sun. Combining with the Spitzer resolved image at 24 μ m and 15–38 μ m excess spectrum, we examine two proposed origins of the inner debris in ϵ Eri: (1) in situ planetesimal belt(s) and (2) dragged-in grains from the cold outer belt. We find that the presence of in situ dust-producing planetesmial belt(s) is the most likely source of the excess emission in the inner 25 au region. Although a small amount of dragged-in grains from the cold belt could contribute to the excess emission in the inner region, the resolution of the SOFIA data is high enough to rule outmore » the possibility that the entire inner warm excess results from dragged-in grains, but not enough to distinguish one broad inner disk from two narrow belts.« less

Authors:
; ;  [1]; ;  [2]; ;  [3];  [4];  [5]
  1. Steward Observatory, University of Arizona, 933 N Cherry Avenue, Tucson, AZ 85721 (United States)
  2. SOFIA-USRA, NASA Ames Research Center, MS 232-12, Moffett Field, CA 94035 (United States)
  3. Astrophysikalisches Institut und Universitätssternwarte, Friedrich-Schiller-Universität Jena, Schillergäßchen 2–3, D-07745 Jena (Germany)
  4. Department of Physics and Astronomy, Iowa State University, Ames, IA 50011 (United States)
  5. Jet Propulsion Laboratory, California Institute of Technology, 4800 Oak Grove Drive, Pasadena, CA 91109 (United States)
Publication Date:
OSTI Identifier:
22663670
Resource Type:
Journal Article
Resource Relation:
Journal Name: Astronomical Journal (Online); Journal Volume: 153; Journal Issue: 5; Other Information: Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; ASTRONOMY; COSMIC DUST; ENERGY SPECTRA; IMAGES; INFRARED SPECTRA; MORPHOLOGY; PARTICLE SIZE; PARTICLES; RESOLUTION; SUN; WAVELENGTHS

Citation Formats

Su, Kate Y. L., Rieke, George H., Ballering, Nicholas P., De Buizer, James M., Vacca, William D., Krivov, Alexander V., Löhne, Torsten, Marengo, Massimo, and Stapelfeldt, Karl R. The Inner 25 au Debris Distribution in the ϵ Eri System. United States: N. p., 2017. Web. doi:10.3847/1538-3881/AA696B.
Su, Kate Y. L., Rieke, George H., Ballering, Nicholas P., De Buizer, James M., Vacca, William D., Krivov, Alexander V., Löhne, Torsten, Marengo, Massimo, & Stapelfeldt, Karl R. The Inner 25 au Debris Distribution in the ϵ Eri System. United States. doi:10.3847/1538-3881/AA696B.
Su, Kate Y. L., Rieke, George H., Ballering, Nicholas P., De Buizer, James M., Vacca, William D., Krivov, Alexander V., Löhne, Torsten, Marengo, Massimo, and Stapelfeldt, Karl R. Mon . "The Inner 25 au Debris Distribution in the ϵ Eri System". United States. doi:10.3847/1538-3881/AA696B.
@article{osti_22663670,
title = {The Inner 25 au Debris Distribution in the ϵ Eri System},
author = {Su, Kate Y. L. and Rieke, George H. and Ballering, Nicholas P. and De Buizer, James M. and Vacca, William D. and Krivov, Alexander V. and Löhne, Torsten and Marengo, Massimo and Stapelfeldt, Karl R.},
abstractNote = {Debris disk morphology is wavelength dependent due to the wide range of particle sizes and size-dependent dynamics influenced by various forces. Resolved images of nearby debris disks reveal complex disk structures that are difficult to distinguish from their spectral energy distributions. Therefore, multi-wavelength resolved images of nearby debris systems provide an essential foundation to understand the intricate interplay between collisional, gravitational, and radiative forces that govern debris disk structures. We present the Stratospheric Observatory for Infrared Astronomy (SOFIA) 35 μ m resolved disk image of ϵ Eri, the closest debris disk around a star similar to the early Sun. Combining with the Spitzer resolved image at 24 μ m and 15–38 μ m excess spectrum, we examine two proposed origins of the inner debris in ϵ Eri: (1) in situ planetesimal belt(s) and (2) dragged-in grains from the cold outer belt. We find that the presence of in situ dust-producing planetesmial belt(s) is the most likely source of the excess emission in the inner 25 au region. Although a small amount of dragged-in grains from the cold belt could contribute to the excess emission in the inner region, the resolution of the SOFIA data is high enough to rule out the possibility that the entire inner warm excess results from dragged-in grains, but not enough to distinguish one broad inner disk from two narrow belts.},
doi = {10.3847/1538-3881/AA696B},
journal = {Astronomical Journal (Online)},
number = 5,
volume = 153,
place = {United States},
year = {Mon May 01 00:00:00 EDT 2017},
month = {Mon May 01 00:00:00 EDT 2017}
}
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