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arXiv · 0710.3754

Mid-Infrared Photometry and Spectra of Three High Mass Protostellar Candidates at IRAS 18151-1208 and IRAS 20343+4129

M. F. Campbell·T. K. Sridharan·H. Beuther·J. H. Lacy·J. L. Hora·Q. Zhu·M. Kassis·M. Saito·J. M. De Buizer·S. H. Fung·L. C. Johnson
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Abstract

We present arcsecond-scale mid-ir photometry (in the 10.5 micron N band and at 24.8 microns), and low resolution spectra in the N band (R~100) of a candidate high mass protostellar object (HMPO) in IRAS 18151-1208 and of two HMPO candidates in IRAS 20343+4129, IRS 1 and IRS 3. In addition we present high resolution mid-ir spectra (R~80000) of the two HMPO candidates in IRAS 20343+4129. These data are fitted with simple models to estimate the masses of gas and dust associated with the mid-ir emitting clumps, the column densities of overlying absorbing dust and gas, the luminosities of the HMPO candidates, and the likely spectral type of the HMPO candidate for which [Ne II] 12.8 micron emission was detected (IRAS 20343+4129 IRS 3). We suggest that IRAS 18151-1208 is a pre-ultracompact HII region HMPO, IRAS 20343+4129 IRS 1 is an embedded young stellar object with the luminosity of a B3 star, and IRAS 20343+4129 IRS 3 is a B2 ZAMS star that has formed an ultracompact HII region and disrupted its natal envelope.

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M. F. Campbell, T. K. Sridharan, H. Beuther, J. H. Lacy, J. L. Hora, Q. Zhu, M. Kassis, M. Saito, J. M. De Buizer, S. H. Fung, L. C. Johnson. 2007-10-19. Mid-Infrared Photometry and Spectra of Three High Mass Protostellar Candidates at IRAS 18151-1208 and IRAS 20343+4129. https://doi.org/10.1086/524768

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