TESTING THE HYPOTHESIS THAT METHANOL MASER RINGS TRACE CIRCUMSTELLAR DISKS: HIGH-RESOLUTION NEAR-INFRARED AND MID-INFRARED IMAGING

Journal Article · Wed Aug 01 04:00:00 EDT 2012 · Astrophysical Journal

DOI:https://doi.org/10.1088/0004-637X/754/2/149· OSTI ID:22039211

De Buizer, James M ^[1]; Bartkiewicz, Anna; Szymczak, Marian ^[2]

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1. Stratospheric Observatory for Infrared Astronomy-USRA, NASA Ames Research Center, MS N232-12, Moffett Field, CA 94035 (United States)
2. Torun Centre for Astronomy, Nicolaus Copernicus University, Gagarina 11, 87-100 Torun (Poland)

Milliarcsecond very long baseline interferometry maps of regions containing 6.7 GHz methanol maser emission have lead to the recent discovery of ring-like distributions of maser spots and the plausible hypothesis that they may be tracing circumstellar disks around forming high-mass stars. We aimed to test this hypothesis by imaging these regions in the near- and mid-infrared at high spatial resolution and compare the observed emission to the expected infrared morphologies as inferred from the geometries of the maser rings. In the near-infrared we used the Gemini North adaptive optics system of ALTAIR/NIRI, while in the mid-infrared we used the combination of the Gemini South instrument T-ReCS and super-resolution techniques. Resultant images had a resolution of {approx}150 mas in both the near-infrared and mid-infrared. We discuss the expected distribution of circumstellar material around young and massive accreting (proto)stars and what infrared emission geometries would be expected for the different maser ring orientations under the assumption that the masers are coming from within circumstellar disks. Based upon the observed infrared emission geometries for the four targets in our sample and the results of spectral energy distribution modeling of the massive young stellar objects associated with the maser rings, we do not find compelling evidence in support of the hypothesis that methanol masers rings reside in circumstellar disks.

• OSTI ID: 22039211
• Journal Information: Astrophysical Journal, Journal Name: Astrophysical Journal Journal Issue: 2 Vol. 754; ISSN ASJOAB; ISSN 0004-637X
• Country of Publication: United States
• Language: English

Related Subjects

79 ASTRONOMY AND ASTROPHYSICS
ASTRONOMY
ASTROPHYSICS
COMPARATIVE EVALUATIONS
ENERGY SPECTRA
GHZ RANGE
IMAGES
INTERFEROMETRY
INTERMEDIATE INFRARED RADIATION
MASERS
MASS
METHANOL
MORPHOLOGY
NEAR INFRARED RADIATION
OPTICS
ORIENTATION
PHOTON EMISSION
SPATIAL RESOLUTION
STAR ACCRETION
STARS