J/AJ/157/202ivo://CDS.VizieR/J/AJ/157/202doi:10.26093/cds/vizier.51570202CDSSu K.Y.L.Jackson A.P.Gaspar A.Rieke G.H.Dong R.Olofsson J.,Kennedy G.M.Leinhardt Z.M.Malhotra R.Hammer M.Meng H.Y.A.,Rujopakarn W.Rodriguez J.E.Pepper J.Reichart D.E.James D.,Stassun K.G.2019-08-21T11:48:40Z2019-08-14T06:45:42ZCDS support team

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

cds-question@unistra.frg-starsinfrared-photometryThe most dramatic phases of terrestrial planet formation are thought to be oligarchic and chaotic growth, on timescales of up to 100-200 Myr, when violent impacts occur between large planetesimals of sizes up to protoplanets. Such events are marked by the production of large amounts of debris, as has been observed in some exceptionally bright and young debris disks (termed extreme debris disks). Here we report five years of Spitzer measurements of such systems around two young solar-type stars: ID8 and P1121. The short-term (weekly to monthly) and long-term (yearly) disk variability is consistent with the aftermaths of large impacts involving large asteroid-sized bodies. We demonstrate that an impact-produced clump of optically thick dust, under the influence of the dynamical and viewing geometry effects, can produce short-term modulation in the disk light curves. The long-term disk flux variation is related to the collisional evolution within the impact-produced fragments once released into a circumstellar orbit. The time-variable behavior observed in the P1121 system is consistent with a hypervelocity impact prior to 2012 that produced vapor condensates as the dominant impact product. Two distinct short-term modulations in the ID8 system suggest two violent impacts at different times and locations. Its long-term variation is consistent with the collisional evolution of two different populations of impact-produced debris dominated by either vapor condensates or escaping boulders. The bright, variable emission from the dust produced in large impacts from extreme debris disks provides a unique opportunity to study violent events during the era of terrestrial planet formation.2019AJ....157..202Shttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/AJ/157/202CatalogResearchIsServedByTAP VizieR generic servicerelated-toJ/ApJ/636/1098 : Debris disks around solar-type stars (Bryden+, 2006)J/ApJ/705/89 : IRS spectra of solar-type stars (Lawler+, 2009)J/ApJS/211/25 : Spitzer/IRS debris disk catalog. I. (Chen+, 2014)J/ApJ/798/87 : Spitzer/IRS debris disk catalog. II. (Mittal+, 2015)J/ApJ/805/77 : Spitzer 3.6 and 4.5um monitoring of 5 stars (Meng+, 2015)https://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/AJ/157/202https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/AJ/157/202http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/AJ/157/202https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/AJ/157/202https://vizier.iucaa.in/viz-bin/votable?-source=J/AJ/157/202http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/AJ/157/202GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tap3.9193497546148093e-20 6.185923063528282e-20InfrareddefaultJ/AJ/157/202/table1The IRAC fluxes of the ID8 systemrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintAOR[45677056/61677824] Spitzer Astronomical Observation Request (AOR) keymeta.id;obsintBMJD3.6[56072.71322/58018.37332]? Barycentric Modified Julian Date of the 3.6 micron observationdtime.epochdoublenullableF3.6[9.31/11.93]? Spitzer/IRAC 3.6 micron band flux densitymJyphot.mag;em.IR.3-4umfloatnullablee_F3.6[0.01/0.13]? Uncertainty in F3.6mJystat.errorfloatnullableexF3.6[0.47/3.37]? Excess 3.6 micron flux density (1)mJyphot.mag;em.IR.3-4umfloatnullablee_exF3.6[0.13/0.19]? Uncertainty in exF3.6mJystat.errorfloatnullableBMJD4.5[56072.70783/58018.36796] Barycentric Modified Julian Date of the 4.5 micron observationdtime.epochdoubleF4.5[6.91/10.47] Spitzer/IRAC 4.5 micron band flux densitymJyphot.mag;em.IR.4-8umfloate_F4.5[0.01/0.33] Uncertainty in F4.5mJystat.errorfloatexF4.5[0.74/4.84] Excess 4.5 micron flux density (1)mJyphot.mag;em.IR.4-8umfloate_exF4.5[0.09/0.35] Uncertainty in exF4.5mJystat.errorfloatJ/AJ/157/202/table2The IRAC fluxes of the P1121 systemrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintAOR[45677056/61677824] Spitzer Astronomical Observation Request (AOR) keymeta.id;obsintBMJD3.6[56072.71322/58018.37332]? Barycentric Modified Julian Date of the 3.6 micron observationdtime.epochdoublenullableF3.6[9.31/11.93]? Spitzer/IRAC 3.6 micron band flux densitymJyphot.mag;em.IR.3-4umfloatnullablee_F3.6[0.01/0.13]? Uncertainty in F3.6mJystat.errorfloatnullableexF3.6[0.47/3.37]? Excess 3.6 micron flux density (1)mJyphot.mag;em.IR.3-4umfloatnullablee_exF3.6[0.13/0.19]? Uncertainty in exF3.6mJystat.errorfloatnullableBMJD4.5[56072.70783/58018.36796] Barycentric Modified Julian Date of the 4.5 micron observationdtime.epochdoubleF4.5[6.91/10.47] Spitzer/IRAC 4.5 micron band flux densitymJyphot.mag;em.IR.4-8umfloate_F4.5[0.01/0.33] Uncertainty in F4.5mJystat.errorfloatexF4.5[0.74/4.84] Excess 4.5 micron flux density (1)mJyphot.mag;em.IR.4-8umfloate_exF4.5[0.09/0.35] Uncertainty in exF4.5mJystat.errorfloat