The browser you are using is not supported by this website. All versions of Internet Explorer are no longer supported, either by us or Microsoft (read more here: https://www.microsoft.com/en-us/microsoft-365/windows/end-of-ie-support).

Please use a modern browser to fully experience our website, such as the newest versions of Edge, Chrome, Firefox or Safari etc.

Nils Ryde

Nils Ryde

Professor

Nils Ryde

SOFIA/EXES observations of water absorption in the protostar AFGL 2591 at high spectral resolution

Author

  • Nick Indriolo
  • D. A. Neufeld
  • C. N. DeWitt
  • M. J. Richter
  • A. C. A. Boogert
  • G. M. Harper
  • D. T. Jaffe
  • K. R. Kulas
  • M. E. McKelvey
  • Nils Ryde
  • W. Vacca

Summary, in English

We present high spectral resolution (similar to 3 km s(-1)) observations of the nu(2) ro-vibrational band of H2O in the 6.086-6.135 mu m range toward the massive protostar AFGL 2591 using the Echelon-Cross-Echelle Spectrograph (EXES) on the Stratospheric Observatory for Infrared Astronomy (SOFIA). Ten absorption features are detected in total, with seven caused by transitions in the nu(2) band of H2O, two by transitions in the first vibrationally excited nu(2) band of H2O, and one by a transition in the nu(2) band of (H2O)-O-18. Among the detected transitions is the nu(2) 1(1,1)-0(0,0) line that probes the lowest-lying rotational level of para-H2O. The stronger transitions appear to be optically thick, but reach maximum absorption at a depth of about 25%, suggesting that the background source is only partially covered by the absorbing gas or that the absorption arises within the 6 mu m emitting photosphere. Assuming a covering fraction of 25%, the H2O column density and rotational temperature that best fit the observed absorption lines are N(H2O) = (1.3 +/- 0.3) x 10(19) cm(-2) and T = 640 +/- 80 K.

Department/s

  • Lund Observatory

Publishing year

2015

Language

English

Publication/Series

Astrophysical Journal Letters

Volume

802

Issue

2

Document type

Journal article

Publisher

IOP Publishing

Topic

  • Astronomy, Astrophysics and Cosmology

Keywords

  • stars: protostars

Status

Published

ISBN/ISSN/Other

  • ISSN: 2041-8213