J/ApJ/733/L31ivo://CDS.VizieR/J/ApJ/733/L31doi:10.26093/cds/vizier.17339031CDSMakide K.Nagashima K.Krot A.N.Huss G.R.Ciesla F.J.Hellebrand E.,Gaidos E.Yang L.2013-01-06T08:29:35Z2012-12-19T08:39:26ZCDS support team

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

cds-question@unistra.frsolar-systematomic-physicscometsIt is believed that ^26^Al, a short-lived (t_1/2_=0.73Ma) and now extinct radionuclide, was uniformly distributed in the nascent solar system (SS) with the initial ^26^Al/^27^Al ratio of ~5.2x10^-5^, suggesting an external, stellar origin rather than local, solar source. However, the stellar source of ^26^Al and the manner in which it was injected into the SS remain controversial: the ^26^Al could have been produced by an asymptotic giant branch star, a supernova, or a Wolf-Rayet star and injected either into the protosolar molecular cloud, protosolar cloud core, or protoplanetary disk. Corundum (Al_2_O_3_) is predicted to be the first condensate from a cooling gas of solar composition. Here we show that micron-sized corundum condensates from ^16^O-rich ({Delta}^17^O~-25%) gas of solar composition recorded heterogeneous distribution of ^26^Al at the birth of the SS: the inferred initial ^26^Al/^27^Al ratio ranges from ~6.5x10^-5^ to <2x10^-6^; 52% of corundum grains measured are ^26^Al-poor. Abundant ^26^Al-poor, ^16^O-rich refractory objects include grossite- and hibonite-rich calcium-aluminum-rich inclusions (CAIs) in CH (high metal abundance and high iron concentration) chondrites, platy hibonite crystals in CM (Mighei-like) chondrites, and CAIs with fractionation and unidentified nuclear effects CAIs chondrites. Considering the apparently early and short duration (<0.3Ma) of condensation of refractory ^16^O-rich solids in the SS, we infer that ^26^Al was injected into the collapsing protosolar molecular cloud and later homogenized in the protoplanetary disk. The apparent lack of correlation between ^26^Al abundance and O-isotope composition of corundum grains constrains the stellar source of ^26^Al in the SS.2011ApJ...733L..31Mhttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/ApJ/733/L31CatalogResearchIsServedByTAP VizieR generic servicehttps://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/ApJ/733/L31https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/ApJ/733/L31http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/ApJ/733/L31https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/ApJ/733/L31https://vizier.iucaa.in/viz-bin/votable?-source=J/ApJ/733/L31http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/ApJ/733/L31GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapdefaultJ/ApJ/733/L31/table1Oxygen-isotope compositions and the inferred (^26^Al/^27^Al)_0_ ratios from individual micron-sized corundum grain in unequilibrated ordinary chondrites (UOCs) and unmetamorphosed CM carbonaceous chondrites (CCs)recnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintTypechondrite type (Carbonaceus or Ordinary)src.classcharGrainGrain (1)meta.id;meta.mainchard18OExcess {delta}^18^O of ^18^O isotopephys.abundfloate_d18OThe 2{sigma} error in d180stat.errorfloatd17OExcess {delta}^18^O of ^17^O isotopephys.abundfloate_d17OThe 2{sigma} error in d170stat.errorfloatD17O{Delta}^17^O composition (D17O=d17O-0.52*d18O)phys.abundfloate_D17OThe 2{sigma} error in D17Ostat.errorfloatAl.r? Inferred (^26^Al/^27^Al)_0_ ratio (2)phys.abundfloatnullablee_Al.r? The 2{sigma} error in Al.rstat.errorfloatnullable