J/ApJ/898/21ivo://CDS.VizieR/J/ApJ/898/21doi:10.26093/cds/vizier.18980021CDSSu K.Y.L.Rieke G.H.Melis C.Jackson A.P.Smith P.S.Meng H.Y.A.,Gaspar A.2022-03-21T07:07:57Z2021-12-07T10:36:10ZCDS support team

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

cds-question@unistra.frinfrared-photometrymultiple-starsearly-type-starsWe present multiepoch infrared photometry and spectroscopy obtained with warm Spitzer, Subaru, and the Stratospheric Observatory for Infrared Astronomy to assess variability for the young (~20Myr) and dusty debris systems around HD 172555 and HD 113766A. No variations (within 0.5%) were found for the former at either 3.6 or 4.5{mu}m, while significant nonperiodic variations (peak to peak of ~10%-15% relative to the primary star) were detected for the latter. Relative to the Spitzer Infrared Spectrograph spectra taken in 2004, multiepoch mid-infrared spectra reveal no change in either the shape of the prominent 10{mu}m solid-state features or the overall flux levels (no more than 20%) for both systems, corroborating the fact that the population of submicron-size grains that produce the pronounced solid-state features is stable over a decadal timescale. We suggest that these submicron-size grains were initially generated in an optically thick clump of debris of millimeter-size vapor condensates resulting from a recent violent impact between large asteroidal or planetary bodies. Because of the shielding from the stellar photons provided by this clump, intense collisions led to an overproduction of fine grains that would otherwise be ejected from the system by radiation pressure. As the clump is sheared by its orbital motion and becomes optically thin, a population of very fine grains could remain in stable orbits until Poynting-Robertson drag slowly spirals them into the star. We further suggest that the 3-5{mu}m disk variation around HD 113766A is consistent with a clump/arc of such fine grains on a modestly eccentric orbit in its terrestrial zone.2020ApJ...898...21Shttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/ApJ/898/21CatalogResearchIsServedByTAP VizieR generic servicerelated-toII/328 : AllWISE Data Release (Cutri+ 2013)I/345 : Gaia DR2 (Gaia Collaboration, 2018)J/A+A/356/141 : BV photometry for components of HIP doubles (Fabricius+ 2000)J/A+A/460/695 : Search for Associations Containing Young stars (Torres+, 2006)J/AJ/135/2245 : Absolute spectrum of Sun & Vega for 0.2-30um (Rieke+, 2008)J/ApJ/698/1989 : Spitzer survey of NGC 2451 (Balog+, 2009)J/ApJ/705/89 : IRS spectra of solar-type stars (Lawler+, 2009)J/ApJ/738/122 : ScoCen debris disks Around F- and G-type stars (Chen+, 2011)J/ApJ/746/154 : Improved parallaxes for Sco-Cen members (Pecaut+, 2012)J/ApJ/785/33 : High quality Spitzer/MIPS obs. of F-K stars (Sierchio+, 2014)J/ApJ/805/77 : Spitzer 3.6 and 4.5um monitoring of 5 stars (Meng+, 2015)J/ApJ/798/87 : Spitzer/IRS debris disk catalog. II. (Mittal+, 2015)J/ApJ/845/120 : Spitzer obs. of warm dust in debris disks (Ballering+, 2017)J/ApJ/836/34 : 24um excesses & membership of NGC2244 (Meng+, 2017)J/A+A/618/A151 : HD 172555 polarimetric images (Engler+, 2018)J/AJ/157/202 : IRAC fluxes of the ID8 and P1121 systems (Su+, 2019)https://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/ApJ/898/21https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/ApJ/898/21http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/ApJ/898/21https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/ApJ/898/21https://vizier.iucaa.in/viz-bin/votable?-source=J/ApJ/898/21http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/ApJ/898/21GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tap3.9193497546148093e-20 6.185923063528282e-20InfrareddefaultJ/ApJ/898/21/tablea1The IRAC fluxes of the HD 113766 systemrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintAORKEY[48318464/61718528] Spizter AOR Keymeta.id;obsintBMJD3.6[56455.2/58450.2] Barycentric Modified Julian Date, 3.6um obs (JD-2400000.5)dtime.epochdoubleF3.6[772/5385] Spitzer/IRAC Band 1 (3.6um) flux (including star)mJyphot.mag;em.IR.3-4umdoublee_F3.6[0.6/6.1] Uncertainty in Flux-3.6mJystat.errorfloatEF3.6[44/87]? Excess flux (excluding star)mJyphot.flux;arith.ratiofloatnullablee_EF3.6[11/12.5]? Uncertainty in excFlux-3.6mJystat.errorfloatnullableBMJD4.5[57128.5/58450.2]? Barycentric Modified Julian Date, 4.5um obs (JD-2400000.5)dtime.epochdoublenullableF4.5[639/3510.5]? Spitzer/IRAC Band 2 (4.5um) flux (including star)mJyphot.mag;em.IR.4-8umdoublenullablee_F4.5[0.7/3.4]? Uncertainty in Flux-4.5mJystat.errorfloatnullableEF4.5[183/236]? Excess flux (excluding star)mJyphot.flux;arith.ratiofloatnullablee_EF4.5[6.8/7.7]? Uncertainty in excFlux-4.5mJystat.errorfloatnullableJ/ApJ/898/21/tablea2The IRAC fluxes of the HD 172555 systemrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintAORKEY[48318464/61718528] Spizter AOR Keymeta.id;obsintBMJD3.6[56455.2/58450.2] Barycentric Modified Julian Date, 3.6um obs (JD-2400000.5)dtime.epochdoubleF3.6[772/5385] Spitzer/IRAC Band 1 (3.6um) flux (including star)mJyphot.mag;em.IR.3-4umdoublee_F3.6[0.6/6.1] Uncertainty in Flux-3.6mJystat.errorfloatBMJD4.5[57128.5/58450.2]? Barycentric Modified Julian Date, 4.5um obs (JD-2400000.5)dtime.epochdoublenullableF4.5[639/3510.5]? Spitzer/IRAC Band 2 (4.5um) flux (including star)mJyphot.mag;em.IR.4-8umdoublenullablee_F4.5[0.7/3.4]? Uncertainty in Flux-4.5mJystat.errorfloatnullable