J/A+A/365/545ivo://CDS.VizieR/J/A+A/365/545doi:10.26093/cds/vizier.33650545CDSHabing H.J.Dominik C.Jourdain de Muizon M.Laureijs R.J.Kessler M.F.,Leech K.Metcalfe L.Siebenmorgen R.Trams N.Bouchet P.2001-01-20T13:47:29Z2001-01-20T14:46:19ZCDS support team

CDS, Observatoire de Strasbourg, 11 rue de l'Universite, F-67000 Strasbourg, France

cds-question@unistra.frdwarf-starsinfrared-sourcesvisible-astronomyWide-band photometryWe present photometric ISO 60 and 170{mu}m measurements, complemented by some IRAS data at 60{mu}m, of a sample of 84 nearby main-sequence stars of spectral class A, F, G and K in order to determine the incidence of dust disks around such main-sequence stars. Fifty stars were detected at 60{mu}m; 36 of these emit a flux expected from their photosphere while 14 emit significantly more. The excess emission we attribute to a circumstellar disk like the ones around Vega and {beta} Pictoris. Thirty four stars were not detected at all; the expected photospheric flux, however, is so close to the detection limit that the stars cannot have an excess stronger than the photospheric flux density at 60{mu}m. Of the stars younger than 400Myr one in two has a disk; for the older stars this is true for only one in ten. We conclude that most stars arrive on the main sequence surrounded by a disk; this disk then decays in about 400Myr. Because (i) the dust particles disappear and must be replenished on a much shorter time scale and (ii) the collision of planetesimals is a good source of new dust, we suggest that the rapid decay of the disks is caused by the destruction and escape of planetesimals. We suggest that the dissipation of the disk is related to the heavy bombardment phase in our Solar System. Whether all stars arrive on the main sequence surrounded by a disk cannot be established: some very young stars do not have a disk. And not all stars destroy their disk in a similar way: some stars as old as the Sun still have significant disks.2001A&A...365..545Hhttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/A+A/365/545CatalogResearchIsServedByTAP VizieR generic servicerelated-toI/239 : The Hipparcos and Tycho Catalogues (ESA 1997)III/135 : Henry Draper Catalogue and Extension (Cannon+ 1918-1924; ADC 1989)https://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/A+A/365/545https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/A+A/365/545http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/A+A/365/545https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/A+A/365/545https://vizier.iucaa.in/viz-bin/votable?-source=J/A+A/365/545http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/A+A/365/545GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapOpticalInfrareddefaultJ/A+A/365/545/table2Basic data on all starsrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintHDStar number in the Henry Draper Catalogue (Cat. <III/135>)meta.id;meta.mainintprimarySimbadask the SIMBAD data-base about this objectmeta.refcharHIP? Star number in the HIPPARCOS catalogue (Cat. <I/239>)meta.idintnullableNameStellar namemeta.idcharVmagV-magnitude taken from the Geneva photometric cataloguemagphot.mag;em.opt.VfloatB-VB-V colour taken from the Geneva photometric cataloguemagphot.color;em.opt.B;em.opt.VfloatDistStellar distance, taken from the Hipparcos catalogue (<I/239>)pcpos.distancefloatSpTypeSpectral type taken from the Hipparcos catalogue (<I/239>)src.spTypecharAge? Stellar ageGyrtime.agefloatnullableTeffEffective temperatureKphys.temperature.effectiveintJ/A+A/365/545/table360 micron flux densitiesrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintHDStar number in the Henry Draper Cataloguemeta.id;meta.mainintprimaryISO-ID? Identification number of the measurement used in the ISO archivemeta.idintnullableFnuFlux density corrected for bandwidth effects (4) (1)mJyphot.flux.density;em.IR.30-60uminte_FnuError on Fnu (4) (2)mJystat.errorintFnup? Flux expected from the stellar photosphere (see the text) (4)mJyphot.flux.density;em.IR.30-60umintnullableEFnuExcess flux (Fnu - Fnup) (4) (5)mJyphot.flux;meta.modelledintl_EFnu/e_FnuLimit flag on EFnu/e_Fnumeta.code.errorcharEFnu/e_FnuRatio of the excess flux compared to the measurement errorphot.flux;arith.ratiofloatFnud? Monochromatic excess flux density (3)mJyphot.flux;meta.modelledintnullablel_log(tau)dLimit flag on log(tau)dmeta.code.errorcharlog(tau)d? An estimate of the optical depth of the disk at visual wavelengths, but estimated from the flux density at 60 micronphys.absorption.opticalDepthfloatnullableRefMode of observation reference (table3 only)meta.code;obscharJ/A+A/365/545/table4170 micron flux densitiese_FnuError on Fnu (4) (2)mJystat.errorintrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintHDStar number in the Henry Draper Cataloguemeta.numberintISO-ID? Identification number of the measurement used in the ISO archivemeta.idintnullableFnuFlux density corrected for bandwidth effects (4) (1)mJyphot.flux.density;em.mm.1500-3000GHzintFnup? Flux expected from the stellar photosphere (see the text) (4)mJyphot.flux.density;em.mm.1500-3000GHzintnullableEFnuExcess flux (Fnu - Fnup) (4) (5)mJyphot.flux;meta.modelledintl_EFnu/e_FnuLimit flag on EFnu/e_Fnumeta.code.errorcharEFnu/e_FnuRatio of the excess flux compared to the measurement errorphot.flux;arith.ratiofloatFnud? Monochromatic excess flux density (3)mJyphot.flux;meta.modelledintnullablel_log(tau)dLimit flag on log(tau)dmeta.code.errorcharlog(tau)d? An estimate of the optical depth of the disk at visual wavelengths, but estimated from the flux density at 60 micronphys.absorption.opticalDepthfloatnullableRefMode of observation reference (table3 only)meta.code;obschar