DUst around NEarby Stars. The survey observational results
Artikel i vetenskaplig tidskrift, 2013

Context. Debris discs are a consequence of the planet formation process and constitute the fingerprints of planetesimal systems. Their solar system counterparts are the asteroid and Edgeworth-Kuiper belts. Aims. The DUNES survey aims at detecting extra-solar analogues to the Edgeworth-Kuiper belt around solar-type stars, putting in this way the solar system into context. The survey allows us to address some questions related to the prevalence and properties of planetesimal systems. Methods. We used Herschel/PACS to observe a sample of nearby FGK stars. Data at 100 and 160 mu m were obtained, complemented in some cases with observations at 70 mu m, and at 250, 350 and 500 mu m using SPIRE. The observing strategy was to integrate as deep as possible at 100 mu m to detect the stellar photosphere. Results. Debris discs have been detected at a fractional luminosity level down to several times that of the Edgeworth-Kuiper belt. The incidence rate of discs around the DUNES stars is increased from a rate of similar to 12.1% +/- 5% before Herschel to similar to 20.2% +/- 2%. A significant fraction (similar to 52%) of the discs are resolved, which represents an enormous step ahead from the previously known resolved discs. Some stars are associated with faint far-IR excesses attributed to a new class of cold discs. Although it cannot be excluded that these excesses are produced by coincidental alignment of background galaxies, statistical arguments suggest that at least some of them are true debris discs. Some discs display peculiar SEDs with spectral indexes in the 70-160 mu m range steeper than the Rayleigh-Jeans one. An analysis of the debris disc parameters suggests that a decrease might exist of the mean black body radius from the F-type to the K-type stars. In addition, a weak trend is suggested for a correlation of disc sizes and an anticorrelation of disc temperatures with the stellar age.

planetary systems

infrared: stars

circumstellar matter

Författare

C. Eiroa

Universidad Autonoma de Madrid (UAM)

J. P. Marshall

Universidad Autonoma de Madrid (UAM)

A. Mora

B. Montesinos

Centro de Astrobiologia (CAB)

O. Absil

Universite de Liège

J. C. Augereau

Verimag

A. Bayo

European Space Observatory

Max Planck-institutet

G. Bryden

Jet Propulsion Laboratory, California Institute of Technology

W. Danchi

NASA Goddard Space Flight Center

C. del Burgo

Instituto Nacional de Astrofisica Optica y Electronica

S. Ertel

Verimag

M. Fridlund

ESTEC/SRE-SA

A. Heras

ESTEC/SRE-SA

A. Krivov

Friedrich-Schiller-Universität Jena

R. Launhardt

Max Planck-institutet

René Liseau

Chalmers, Rymd- och geovetenskap, Radioastronomi och astrofysik

T. Lohne

Friedrich-Schiller-Universität Jena

J. Maldonado

Universidad Autonoma de Madrid (UAM)

G.L. Pilbratt

ESTEC/SRE-SA

A. Roberge

NASA Goddard Space Flight Center

J. Rodmann

Georg-August-Universität Göttingen

J. Sanz-Forcada

Centro de Astrobiologia (CAB)

E. Solano

Centro de Astrobiologia (CAB)

K. R. Stapelfeldt

NASA Goddard Space Flight Center

P. Thebault

GEPI - Galaxies, Etoiles, Physique, Instrumentation

S. Wolf

Christian-Albrechts-Universität zu Kiel

D. R. Ardila

CalTech

M. Arevalo

European Space Astronomy Centre (ESA)

Centro de Astrobiologia (CAB)

C. Beichmann

CalTech

V. Faramaz

Verimag

B. M. Gonzalez-Garcia

European Space Astronomy Centre (ESA)

R. Gutierrez

Centro de Astrobiologia (CAB)

J. Lebreton

Verimag

R. Martinez-Arnaiz

Universidad Complutense de Madrid

G. Meeus

Universidad Autonoma de Madrid (UAM)

D. Montes

Universidad Complutense de Madrid

G. Olofsson

Stockholms universitet

K. Y. L. Su

University of Arizona

G. J. White

Rutherford Appleton Laboratory

Open University

D. Barrado

Centro de Astrobiologia (CAB)

Calar Alto Astronomical Observatory

M. Fukagawa

Nagoya University

E. Grun

Max Planck-institutet

I. Kamp

Rijksuniversiteit Groningen

R. Lorente

European Space Astronomy Centre (ESA)

A. Morbidelli

Observatoire de la Cote d'Azur

S. Muller

Friedrich-Schiller-Universität Jena

H. Mutschke

Friedrich-Schiller-Universität Jena

T. Nakagawa

JAXA Institute of Space and Astronautical Science

I. Ribas

Universitat Autonoma de Barcelona (UAB)

H. Walker

Open University

Astronomy and Astrophysics

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

Vol. 555 A11

Ämneskategorier

Astronomi, astrofysik och kosmologi

DOI

10.1051/0004-6361/201321050