SOFIA/FORCAST Observations of the Luminous Blue Variable Candidates MN 90 and HD 168625
AffiliationUniv Arizona, Steward Observ
MetadataShow full item record
PublisherIOP PUBLISHING LTD
CitationRyan A. Arneson et al 2018 ApJ 864 31
Rights© 2018. The American Astronomical Society. All rights reserved.
Collection InformationThis item from the UA Faculty Publications collection is made available by the University of Arizona with support from the University of Arizona Libraries. If you have questions, please contact us at firstname.lastname@example.org.
AbstractWe present Stratospheric Observatory for Infrared Astronomy (SOFIA)/Faint Object infraRed CAmera for the SOFIA Telescope (FORCAST) imaging of the circumstellar dust shells surrounding the luminous blue variable candidates MN 90 and HD 168625 to quantify the mineral abundances of the dust and to constrain the evolutionary state of these objects. Our image at 37.1 mu m of MN 90 shows a limb-brightened, spherical dust shell. A least-squares fit to the spectral energy distribution of MN 90 yields a dust temperature of 59 +/- 10 K, with the peak of the emission at 42.7 mu m. Using 2-Dust radiative transfer code, we estimate for MN 90 that mass loss occurred at a rate of (7.3 +/- 0.4) x 10(-7). M-circle dot yr(-1) x (v(exp)/50 km s(-1)) to create a dust shell with a dust mass of (3.2 +/- 0.1). x. 10(-2) M-circle dot. Our images between 7.7 and 37.1 mu m of HD 168625 complement previously obtained mid-IR imaging of its bipolar nebulae. The SOFIA/FORCAST imaging of HD 168625 shows evidence for the limb-brightened peaks of an equatorial torus. We estimate a dust temperature of 170 +/- 40 K for the equatorial dust surrounding HD 168625, with the peak of the emission at 18.3 mu m. Our 2-Dust model for HD 168625 estimates that mass loss occurred at a rate of (3.2 +/- 0.2) x 10(-7) M-circle dot yr(-1) to create a dust torus/shell with a dust mass of (2.5 +/- 0.1) x 10(-3). M-circle dot.
VersionFinal published version
SponsorsNASA [NNA17BF53C]; Deutsches SOFIA Institut (DSI) under DLR [50 OK 0901]; NASA under USRA [02_0101, 03_0131]; United States Air Force