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Title: A SOFIA FORCAST Grism Study of the Mineralogy of Dust in the Winds of Proto-planetary Nebulae: RV Tauri Stars and SRd Variables

Abstract

We present a SOFIA FORCAST grism spectroscopic survey to examine the mineralogy of the circumstellar dust in a sample of post-asymptotic giant branch (post-AGB) yellow supergiants that are believed to be the precursors of planetary nebulae. Our mineralogical model of each star indicates the presence of both carbon-rich and oxygen-rich dust species—contrary to simple dredge-up models—with a majority of the dust in the form of amorphous carbon and graphite. The oxygen-rich dust is primarily in the form of amorphous silicates. The spectra do not exhibit any prominent crystalline silicate emission features. For most of the systems, our analysis suggests that the grains are relatively large and have undergone significant processing, supporting the hypothesis that the dust is confined to a Keplerian disk and that we are viewing the heavily processed, central regions of the disk from a nearly face-on orientation. These results help to determine the physical properties of the post-AGB circumstellar environment and to constrain models of post-AGB mass loss and planetary nebula formation.

Authors:
; ; ;  [1];  [2];  [3];  [4];  [5];  [6];  [7];  [8];  [9];  [10]
  1. Minnesota Institute for Astrophysics, School of Physics and Astronomy, University of Minnesota, 106 Pleasant Street S.E., Minneapolis, MN 55455 (United States)
  2. USRA-SOFIA Science Center, NASA Ames Research Center, Moffett Field, CA 94035 (United States)
  3. Astrophysics Group, Lennard Jones Laboratory, Keele University, Keele, Staffordshire ST5 5BG (United Kingdom)
  4. Department of Physics and Astronomy, 264 Center for Natural Sciences, Ithaca College, Ithaca, NY 14850 (United States)
  5. National Optical Astronomy Observatory, P.O. Box 26732, Tucson, AZ 85726 (United States)
  6. Department of Physics and Astronomy, University of California, Los Angeles, CA 90095 (United States)
  7. Institute for Astrophysics (IfA), University of Vienna, Türkenschanzstrasse 17, A-1180 Vienna (Austria)
  8. Solar System Exploration Branch, Space Department, Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723 (United States)
  9. Astronomical Institute of the Romanian Academy, Str. Cutitul de Argint 5, Bucharest, 040557 (Romania)
  10. Biomedical Engineering Department, Stony Brook University, Stony Brook, NY 11794 (United States)
Publication Date:
OSTI Identifier:
22663438
Resource Type:
Journal Article
Resource Relation:
Journal Name: Astrophysical Journal; Journal Volume: 843; Journal Issue: 1; Other Information: Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; ASYMPTOTIC SOLUTIONS; DUSTS; EMISSION; HYPOTHESIS; MASS TRANSFER; MINERALOGY; OXYGEN; PLANETARY NEBULAE; SPECTRA; STAR EVOLUTION; STARS; STELLAR WINDS; SUPERGIANT STARS

Citation Formats

Arneson, R. A., Gehrz, R. D., Woodward, C. E., Shenoy, D., Helton, L. A., Evans, A., Keller, L. D., Hinkle, K. H., Jura, M., Lebzelter, T., Lisse, C. M., Rushton, M. T., and Mizrachi, J., E-mail: arneson@astro.umn.edu. A SOFIA FORCAST Grism Study of the Mineralogy of Dust in the Winds of Proto-planetary Nebulae: RV Tauri Stars and SRd Variables. United States: N. p., 2017. Web. doi:10.3847/1538-4357/AA75CF.
Arneson, R. A., Gehrz, R. D., Woodward, C. E., Shenoy, D., Helton, L. A., Evans, A., Keller, L. D., Hinkle, K. H., Jura, M., Lebzelter, T., Lisse, C. M., Rushton, M. T., & Mizrachi, J., E-mail: arneson@astro.umn.edu. A SOFIA FORCAST Grism Study of the Mineralogy of Dust in the Winds of Proto-planetary Nebulae: RV Tauri Stars and SRd Variables. United States. doi:10.3847/1538-4357/AA75CF.
Arneson, R. A., Gehrz, R. D., Woodward, C. E., Shenoy, D., Helton, L. A., Evans, A., Keller, L. D., Hinkle, K. H., Jura, M., Lebzelter, T., Lisse, C. M., Rushton, M. T., and Mizrachi, J., E-mail: arneson@astro.umn.edu. Sat . "A SOFIA FORCAST Grism Study of the Mineralogy of Dust in the Winds of Proto-planetary Nebulae: RV Tauri Stars and SRd Variables". United States. doi:10.3847/1538-4357/AA75CF.
@article{osti_22663438,
title = {A SOFIA FORCAST Grism Study of the Mineralogy of Dust in the Winds of Proto-planetary Nebulae: RV Tauri Stars and SRd Variables},
author = {Arneson, R. A. and Gehrz, R. D. and Woodward, C. E. and Shenoy, D. and Helton, L. A. and Evans, A. and Keller, L. D. and Hinkle, K. H. and Jura, M. and Lebzelter, T. and Lisse, C. M. and Rushton, M. T. and Mizrachi, J., E-mail: arneson@astro.umn.edu},
abstractNote = {We present a SOFIA FORCAST grism spectroscopic survey to examine the mineralogy of the circumstellar dust in a sample of post-asymptotic giant branch (post-AGB) yellow supergiants that are believed to be the precursors of planetary nebulae. Our mineralogical model of each star indicates the presence of both carbon-rich and oxygen-rich dust species—contrary to simple dredge-up models—with a majority of the dust in the form of amorphous carbon and graphite. The oxygen-rich dust is primarily in the form of amorphous silicates. The spectra do not exhibit any prominent crystalline silicate emission features. For most of the systems, our analysis suggests that the grains are relatively large and have undergone significant processing, supporting the hypothesis that the dust is confined to a Keplerian disk and that we are viewing the heavily processed, central regions of the disk from a nearly face-on orientation. These results help to determine the physical properties of the post-AGB circumstellar environment and to constrain models of post-AGB mass loss and planetary nebula formation.},
doi = {10.3847/1538-4357/AA75CF},
journal = {Astrophysical Journal},
number = 1,
volume = 843,
place = {United States},
year = {Sat Jul 01 00:00:00 EDT 2017},
month = {Sat Jul 01 00:00:00 EDT 2017}
}
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