Letter to the Editor

Herschel-SPIRE spectroscopy of G29.96-0.02: Fitting the full SED ^*

¹ School of Physics and Astronomy, Cardiff University, Queens Buildings, The Parade, Cardiff, CF24 3AA, UK e-mail: jason.kirk@astro.cf.ac.uk
² Space Science & Technology Department, Rutherford Appleton Laboratory, Chilton, Didcot, Oxfordshire OX11 0QX, UK
³ Institute for Space Imaging Science, University of Lethbridge, 4401 University Dr., Lethbridge, AB, Canada
⁴ Laboratoire d'Astrophysique de Marseille, UMR 6110 CNRS, 38 rue F. Joliot-Curie, 13388 Marseille, France
⁵ CNRS/INSU, Laboratoire d'Astrophysique de Bordeaux, UMR 5804, BP 89, 33271 Floirac Cedex, France
⁶ Université de Toulouse, UPS, CESR, 9 avenue du colonel Roche, 31028 Toulouse Cedex 4, France
⁷ CNRS, UMR 5187, 31028 Toulouse, France
⁸ Department of Physics & Astronomy, The Open University, Milton Keynes MK7 6AA, UK
⁹ Institut d'Astrophysique Spatiale, UMR 8617, CNRS/Université Paris-Sud 11, 91405 Orsay, France
¹⁰ CEA, Laboratoire AIM, Irfu/SAp, Orme des Merisiers, 91191 Gif-sur-Yvette, France
¹¹ Canadian Institute for Theoretical Astrophysics, Toronto, Ontario, M5S 3H8, Canada
¹² University of California, Radio Astronomy Laboratory, Berkeley, 601 Campbell Hall, US Berkeley CA 94720-3411, USA
¹³ Institut de Radioastronomie Millimétrique (IRAM), 300 rue de la Piscine, 38406 Saint-Martin-d'Hères, France
¹⁴ Joint Astronomy Centre, University Park, Hilo
¹⁵ Blue Sky Spectroscopy Inc, Lethbridge, Canada
¹⁶ National Astronomical Observatories, PR China
¹⁷ Istituto di Fisica dello Spazio Interplanetario, INAF, via del Fosso del Cavaliere 100, 00133 Roma, Italy
¹⁸ NASA – Goddard SFC, USA

Received: 31 March 2010
Accepted: 10 May 2010

Abstract

We use the SPIRE Fourier-transform spectrometer (FTS) on-board the ESA Herschel Space Observatory to analyse the submillimetre spectrum of the Ultra-compact HII region G29.96-0.02. Spectral lines from species including ¹³CO, CO, [CI], and [NII] are detected. A sparse map of the [NII] emission shows at least one other HII region neighbouring the clump containing the UCHII. The FTS spectra are combined with ISO SWS and LWS spectra and fluxes from the literature to present a detailed spectrum of the source spanning three orders of magnitude in wavelength. The quality of the spectrum longwards of 100 μm allows us to fit a single temperature greybody with temperature 80.3±0.6 K and dust emissivity index 1.73±0.02, an accuracy rarely obtained with previous instruments. We estimate a mass of 1500  for the clump containing the HII region. The clump's bolometeric luminosity of 4×10⁶  is comparable to, or slightly greater than, the known O-star powering the UCHII region.