Herschel observations of the debris disc around HIP 92043
Artikel i vetenskaplig tidskrift, 2013

Context. Typical debris discs are composed of particles ranging from several micron sized dust grains to km sized asteroidal bodies, and their infrared emission peaks at wavelengths 60-100 mu m. Recent Herschel DUNES observations have identified several debris discs around nearby Sun-like stars (F, G and K spectral type) with significant excess emission only at 160 mu m. Aims. We observed HIP 92043 (110 Her, HD 173667) at far-infrared and sub-millimetre wavelengths with Herschel PACS and SPIRE. Identification of the presence of excess emission from HIP 92043 and the origin and physical properties of any excess was undertaken through analysis of its spectral energy distribution (SED) and the PACS images. Methods. The PACS and SPIRE images were produced using the HIPE photProject map maker routine. Fluxes were measured using aperture photometry. A stellar photosphere model was scaled to optical and near infrared photometry and subtracted from the far-infared and sub-mm fluxes to determine the presence of excess emission. Source radial profiles were fitted using a 2D Gaussian and compared to a PSF model based on Herschel observations of alpha Boo to check for extended emission. Results. Clear excess emission from HIP 92043 was observed at 70 and 100 mu m. Marginal excess was observed at 160 and 250 mu m. Analysis of the images reveals that the source is extended at 160 mu m. A fit to the source SED is inconsistent with a photosphere and single temperature black body. Conclusions. The excess emission from HIP 92043 is consistent with the presence of an unresolved circumstellar debris disc at 70 and 100 mu m, with low probability of background contamination. The extended 160 mu m emission may be interpreted as an additional cold component to the debris disc or as the result of background contamination along the line of sight. The nature of the 160 mu m excess cannot be determined absolutely from the available data, but we favour a debris disc interpretation, drawing parallels with previously identified cold disc sources in the DUNES sample.

circumstellar matter

Stars: individual: HIP 92043 (110 Her

Infrared: stars

HD 173667)


J. P. Marshall

Universidad Autonoma de Madrid

A. Krivov

Friedrich-Schiller-Universität Jena

C. del Burgo


Instituto Nacional de Astrofisica Optica y Electronica

C. Eiroa

Universidad Autonoma de Madrid

A. Mora

European Space Astronomy Centre

B. Montesinos

CSIC-INTA - Centro de Astrobiologia (CAB)

S. Ertel

Universite Grenoble Alpes

Christian-Albrechts-Universitat zu Kiel

G. Bryden

Jet Propulsion Laboratory, California Institute of Technology

René Liseau

Chalmers, Rymd- och geovetenskap, Onsala rymdobservatorium

Chalmers, Rymd- och geovetenskap, Radioastronomi och astrofysik

J. C. Augereau

Universite Grenoble Alpes

A. Bayo

European Space Observatory

W. Danchi

NASA Goddard Space Flight Center

T. Lohne

Friedrich-Schiller-Universität Jena

J. Maldonado

Universidad Autonoma de Madrid

G.L. Pilbratt

ESTEC - European Space Research and Technology Centre

K. R. Stapelfeldt

NASA Goddard Space Flight Center

P. Thebault

GEPI - Galaxies, Etoiles, Physique, Instrumentation

Universite Grenoble Alpes

G. J. White

Open University

Rutherford Appleton Laboratory

S. Wolf

Christian-Albrechts-Universitat zu Kiel

Astronomy and Astrophysics

0004-6361 (ISSN) 1432-0746 (eISSN)

Vol. 557 A58


Astronomi, astrofysik och kosmologi