View in EDS

In situ identification of a CAI candidate in 81P/Wild 2 cometary dust by confocal high resolution synchrotron X-ray fluorescence

Saved in:
Bibliographic Details
Title: In situ identification of a CAI candidate in 81P/Wild 2 cometary dust by confocal high resolution synchrotron X-ray fluorescence
Authors: Schmitz, Sylvia1 schmitz@em.uni-frankfurt.de, Brenker, Frank E.1, Schoonjans, Tom2, Vekemans, Bart2, Silversmit, Geert2, Vincze, Laszlo2, Burghammer, Manfred3, Riekel, Christian3
Source: Geochimica et Cosmochimica Acta. Sep2009, Vol. 73 Issue 18, p5483-5492. 10p.
Subjects: Cosmic dust, Comets, Aerogels, Space exploration, Principal components analysis, Synchrotron radiation, Optical resolution, X-ray spectroscopy
Abstract: Abstract: We detected additional CAI-like material in STARDUST mission samples of comet 81P/Wild 2. Two highly refractory cometary dust fragments were identified in the impact track 110 [C2012, 0, 110, 0, 0] by applying high resolution synchrotron induced confocal and conventional XRF analysis (HR SR-XRF). The use of a polycapillary lens in front of the detector for confocal spectroscopy dramatically improves the fidelity of particle measurements by removing contribution from the surrounding aerogel. The high spatial resolution (300×300nm2; 300×1000nm2) obtained allowed the detailed non-destructive in situ (trapped in aerogel) study of impacted grains at the sub-μm level. For the two largest particles of the track, the terminal particle and a second particle along the impact track, Ca concentration is up to 30 times higher than CI and Ti is enriched by a factor of 2 compared to CI. High resolution (HR) SR-XRF mapping also reveals that the highest concentrations of Ca, Ti, Fe (and Ni) measured within each grain belongs to different areas of the respective maps which indicate that the particles are composed of several chemically diverse mineral phases. This is in agreement with the finding of a complex phase assemblage of highly refractory minerals in the first ever detected Stardust mission CAI grain “Inti” of Track 25. Principle component analysis (PCA) is a powerful tool for extracting the dominant mineral components and was applied to the two grains indicating that regions in the terminal particle and the second particle are consistent with anorthite or grossite and gehlenite, monticellite or Dmitryivanovite (CaAl2O4), respectively. Our new findings demonstrate that the HR SR-XRF with confocal geometry and PCA analysis is capable of identifying CAI-like fragments without the need to extract particles from the aerogel matrix which is a time-consuming, complex and destructive process. Furthermore, the detection of new CAI-like fragments in the coma dust of comet 81P/Wild 2 strengthens the observation that strong mixing effects and, therefore, mass transport before or during comet formation must have occurred at least up to the region where Kuiper Belt comets formed (∼30AU). [Copyright &y& Elsevier]
Copyright of Geochimica et Cosmochimica Acta is the property of Pergamon Press - An Imprint of Elsevier Science and its content may not be copied or emailed to multiple sites without the copyright holder's express written permission. Additionally, content may not be used with any artificial intelligence tools or machine learning technologies. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)
Database: Engineering Source
FullText Text:
  Availability: 0
Header DbId: egs
DbLabel: Engineering Source
An: 43618490
AccessLevel: 6
PubType: Academic Journal
PubTypeId: academicJournal
PreciseRelevancyScore: 0
IllustrationInfo
Items – Name: Title
  Label: Title
  Group: Ti
  Data: In situ identification of a CAI candidate in 81P/Wild 2 cometary dust by confocal high resolution synchrotron X-ray fluorescence
– Name: Author
  Label: Authors
  Group: Au
  Data: <searchLink fieldCode="AR" term="%22Schmitz%2C+Sylvia%22">Schmitz, Sylvia</searchLink><relatesTo>1</relatesTo><i> schmitz@em.uni-frankfurt.de</i><br /><searchLink fieldCode="AR" term="%22Brenker%2C+Frank+E%2E%22">Brenker, Frank E.</searchLink><relatesTo>1</relatesTo><br /><searchLink fieldCode="AR" term="%22Schoonjans%2C+Tom%22">Schoonjans, Tom</searchLink><relatesTo>2</relatesTo><br /><searchLink fieldCode="AR" term="%22Vekemans%2C+Bart%22">Vekemans, Bart</searchLink><relatesTo>2</relatesTo><br /><searchLink fieldCode="AR" term="%22Silversmit%2C+Geert%22">Silversmit, Geert</searchLink><relatesTo>2</relatesTo><br /><searchLink fieldCode="AR" term="%22Vincze%2C+Laszlo%22">Vincze, Laszlo</searchLink><relatesTo>2</relatesTo><br /><searchLink fieldCode="AR" term="%22Burghammer%2C+Manfred%22">Burghammer, Manfred</searchLink><relatesTo>3</relatesTo><br /><searchLink fieldCode="AR" term="%22Riekel%2C+Christian%22">Riekel, Christian</searchLink><relatesTo>3</relatesTo>
– Name: TitleSource
  Label: Source
  Group: Src
  Data: <searchLink fieldCode="JN" term="%22Geochimica+et+Cosmochimica+Acta%22">Geochimica et Cosmochimica Acta</searchLink>. Sep2009, Vol. 73 Issue 18, p5483-5492. 10p.
– Name: Subject
  Label: Subjects
  Group: Su
  Data: <searchLink fieldCode="DE" term="%22Cosmic+dust%22">Cosmic dust</searchLink><br /><searchLink fieldCode="DE" term="%22Comets%22">Comets</searchLink><br /><searchLink fieldCode="DE" term="%22Aerogels%22">Aerogels</searchLink><br /><searchLink fieldCode="DE" term="%22Space+exploration%22">Space exploration</searchLink><br /><searchLink fieldCode="DE" term="%22Principal+components+analysis%22">Principal components analysis</searchLink><br /><searchLink fieldCode="DE" term="%22Synchrotron+radiation%22">Synchrotron radiation</searchLink><br /><searchLink fieldCode="DE" term="%22Optical+resolution%22">Optical resolution</searchLink><br /><searchLink fieldCode="DE" term="%22X-ray+spectroscopy%22">X-ray spectroscopy</searchLink>
– Name: Abstract
  Label: Abstract
  Group: Ab
  Data: Abstract: We detected additional CAI-like material in STARDUST mission samples of comet 81P/Wild 2. Two highly refractory cometary dust fragments were identified in the impact track 110 [C2012, 0, 110, 0, 0] by applying high resolution synchrotron induced confocal and conventional XRF analysis (HR SR-XRF). The use of a polycapillary lens in front of the detector for confocal spectroscopy dramatically improves the fidelity of particle measurements by removing contribution from the surrounding aerogel. The high spatial resolution (300×300nm2; 300×1000nm2) obtained allowed the detailed non-destructive in situ (trapped in aerogel) study of impacted grains at the sub-μm level. For the two largest particles of the track, the terminal particle and a second particle along the impact track, Ca concentration is up to 30 times higher than CI and Ti is enriched by a factor of 2 compared to CI. High resolution (HR) SR-XRF mapping also reveals that the highest concentrations of Ca, Ti, Fe (and Ni) measured within each grain belongs to different areas of the respective maps which indicate that the particles are composed of several chemically diverse mineral phases. This is in agreement with the finding of a complex phase assemblage of highly refractory minerals in the first ever detected Stardust mission CAI grain “Inti” of Track 25. Principle component analysis (PCA) is a powerful tool for extracting the dominant mineral components and was applied to the two grains indicating that regions in the terminal particle and the second particle are consistent with anorthite or grossite and gehlenite, monticellite or Dmitryivanovite (CaAl2O4), respectively. Our new findings demonstrate that the HR SR-XRF with confocal geometry and PCA analysis is capable of identifying CAI-like fragments without the need to extract particles from the aerogel matrix which is a time-consuming, complex and destructive process. Furthermore, the detection of new CAI-like fragments in the coma dust of comet 81P/Wild 2 strengthens the observation that strong mixing effects and, therefore, mass transport before or during comet formation must have occurred at least up to the region where Kuiper Belt comets formed (∼30AU). [Copyright &y& Elsevier]
– Name: AbstractSuppliedCopyright
  Label:
  Group: Ab
  Data: <i>Copyright of Geochimica et Cosmochimica Acta is the property of Pergamon Press - An Imprint of Elsevier Science and its content may not be copied or emailed to multiple sites without the copyright holder's express written permission. Additionally, content may not be used with any artificial intelligence tools or machine learning technologies. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract.</i> (Copyright applies to all Abstracts.)
PLink https://search.ebscohost.com/login.aspx?direct=true&site=eds-live&db=egs&AN=43618490
RecordInfo BibRecord:
  BibEntity:
    Identifiers:
      – Type: doi
        Value: 10.1016/j.gca.2009.06.008
    Languages:
      – Code: eng
        Text: English
    PhysicalDescription:
      Pagination:
        PageCount: 10
        StartPage: 5483
    Subjects:
      – SubjectFull: Cosmic dust
        Type: general
      – SubjectFull: Comets
        Type: general
      – SubjectFull: Aerogels
        Type: general
      – SubjectFull: Space exploration
        Type: general
      – SubjectFull: Principal components analysis
        Type: general
      – SubjectFull: Synchrotron radiation
        Type: general
      – SubjectFull: Optical resolution
        Type: general
      – SubjectFull: X-ray spectroscopy
        Type: general
    Titles:
      – TitleFull: In situ identification of a CAI candidate in 81P/Wild 2 cometary dust by confocal high resolution synchrotron X-ray fluorescence
        Type: main
  BibRelationships:
    HasContributorRelationships:
      – PersonEntity:
          Name:
            NameFull: Schmitz, Sylvia
      – PersonEntity:
          Name:
            NameFull: Brenker, Frank E.
      – PersonEntity:
          Name:
            NameFull: Schoonjans, Tom
      – PersonEntity:
          Name:
            NameFull: Vekemans, Bart
      – PersonEntity:
          Name:
            NameFull: Silversmit, Geert
      – PersonEntity:
          Name:
            NameFull: Vincze, Laszlo
      – PersonEntity:
          Name:
            NameFull: Burghammer, Manfred
      – PersonEntity:
          Name:
            NameFull: Riekel, Christian
    IsPartOfRelationships:
      – BibEntity:
          Dates:
            – D: 15
              M: 09
              Text: Sep2009
              Type: published
              Y: 2009
          Identifiers:
            – Type: issn-print
              Value: 00167037
          Numbering:
            – Type: volume
              Value: 73
            – Type: issue
              Value: 18
          Titles:
            – TitleFull: Geochimica et Cosmochimica Acta
              Type: main
ResultId 1