Herschel discovery of a new class of cold, faint debris discs

Autor: C. Eiroa, J. P. Marshall, A. Mora, A. V. Krivov, B. Montesinos, O. Absil, D. Ardila, M. Arévalo, J.-Ch. Augereau, A. Bayo, W. Danchi, C. del Burgo, S. Ertel, M. Fridlund, B. M. González-García, A. M. Heras, J. Lebreton, R. Liseau, J. Maldonado, G. Meeus, D. Montes, G. L. Pilbratt, A. Roberge, J. Sanz-Forcada, K. Stapelfeldt, P. Thébault, G. J. White, S. Wolf
Přispěvatelé: UAM. Departamento de Física Teórica, Departemento Física Teórica, Facultad de Ciencias, Universidad Autónoma de Madrid, ESA-ESAC Gaia SOC, PO Box 78, Astrophysikalisches Institut und Universitätssternwarte, Friedrich-Schiller-Universität Jena, Centro de Astrobiología LAEX (CSIC-INTA), Institut d'Astrophysique, Géophysique et Océanographie, Université de Liège, NASA Herschel Science Center, California Institute of Technology (NHSC), Laboratoire d'Astrophysique de Grenoble (LAOG), Université Joseph Fourier - Grenoble 1 (UJF)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), European Southern Observatory, NASA Goddard Space Flight Center, Exoplanets and Stellar Astrophysics, Code 667, Greenbelt, Computational Intelligence Research Group (UNINOVA-CA3), Institut für Theoretische Physik und Astrophysik, Christian-Albrechts-Universität zu Kiel, ESA Astrophysics & Fundamental Physics Missions Division, ESTEC/SRE-SA, INSA at European Space Astronomy Centre (ESAC), European Space Agency, Apartado de Correos 78, Onsala Space Observatory, Chalmers University of Technology (OSO), Universidad Complutense de Madrid = Complutense University of Madrid [Madrid] (UCM), Jet Propulsion Laboratory, California Institute of Technology (JPL), Laboratoire d'études spatiales et d'instrumentation en astrophysique (LESIA), Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), Pôle Planétologie du LESIA, Laboratoire d'études spatiales et d'instrumentation en astrophysique = Laboratory of Space Studies and Instrumentation in Astrophysics (LESIA), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Université Paris Cité (UPCité)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Université Paris Cité (UPCité), Department of Physics and Astronomy, The Open University
Jazyk: angličtina
Rok vydání: 2011
Předmět:
Zdroj: E-Prints Complutense: Archivo Institucional de la UCM
Universidad Complutense de Madrid
Biblos-e Archivo. Repositorio Institucional de la UAM
instname
E-Prints Complutense. Archivo Institucional de la UCM
Astronomy and Astrophysics-A&A
Astronomy and Astrophysics-A&A, 2011, 536, pp.L4. ⟨10.1051/0004-6361/201117797⟩
ISSN: 1432-0746
0004-6361
DOI: 10.1051/0004-6361/201117797⟩
Popis: We present Herschel PACS 100 and 160 micron observations of the solar-type stars alpha Men, HD 88230 and HD 210277, which form part of the FGK stars sample of the Herschel Open Time Key Programme (OTKP) DUNES (DUst around NEarby S tars). Our observations show small infrared excesses at 160 micron for all three stars. HD 210277 also shows a small excess at 100 micron, while the 100 micron fluxes of alpha Men and HD 88230 agree with the stellar photospheric predictions. We attribute these infrared excesses to a new class of cold, faint debris discs. alpha Men and HD 88230 are spatially resolved in the PACS 160 micron images, while HD 210277 is point-like at that wavelength. The projected linear sizes of the extended emission lie in the range from ~ 115 to ~ 250 AU. The estimated black body temperatures from the 100 and 160 micron fluxes are $\lesssim$ 22 K, while the fractional luminosity of the cold dust is Ldust/Lstar ~ 10E-6, close to the luminosity of the Solar-System's Kuiper belt. These debris discs are the coldest and faintest discs discovered so far around mature stars and cannot easily be explained by invoking "classical" debris disc models.
Accepted by Astronomy and Astrophysics Letters
Databáze: OpenAIRE
Externí odkaz: