Experimental approach of dust processing in protoplanetary disks and comparison with returned samples - Mathieu Roskosz
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Experimental approach of dust
processing in protoplanetary disks and
comparison with returned samples
Mathieu Roskosz
Workshop MarcoPolo-R, December 2012, CNES-Hqs
Mathieu.roskosz@univ-lille1.fr
Recuits sur des précurseurs de
diopsides (740°C, 10j)
(thermal annealing)
ISM Vs. Protoplanetary disk
Evaporation/condensation
Thermal annealing
Amorphous-Crystalline
F. Kemper, W. J. Vriend, and A. G. G. M. Tielens R. van Boekel, et al.
Ap. J. 609, 826–837 Nature 432, 479-482
A controversial mineralogical zoning
VLT
Spitzer
An inner disk dominated An outer disk dominated
by pyroxenes by olivine
Detection of SiO2 polymorphs
Watson et al., ApJS 180 (2009) 84-101
Sargent et al., ApJS 182 (2009) 477-508
Sargent et al., ApJ 690 (2009) 1193-1207
R. van Boekel, et al.
Nature 432, 479-482
Experimental details
• 970-1070 K • In situ HT X-ray Diffraction
• A few hours to 2 months • TEM
• Glasses and homogeneous • Conventional XRD
nanoporous volatile-free • Spectroscopies (Raman and IR)
gels
Subsolidus
Quelques crystallization
résultats: 740°C, 10j
Dynamical annealing of MgSiO3
(Roskosz et al., ApJ (2009))
Local and bulk cation dynamics control low-T
dust crystallization
• Even starting from an enstatite precursor, below 700°C, only forsterite forms…
MgSiO3 amorphous Mg2SiO4+SiO2
(Roskosz et al., A&A, 2011)
Mobility decouplings in solids explains the metastable low-temperature
formation of the MgO-(CaO)-rich phases
(Roskosz et al., JNCS (2005) 351, 1266-1282; JNCS (2006) 352, 180-184)
Metastable low-T assemblages identified "
in Stardust samples
Conclusion et applications
Metastable low-T assemblages
in Stardust samples
identified "
Al Si
SiO2
1 µm
Pt Mg
S Fe
500 nm
« Fo58 »
« Fo93 »
Close association of olivines and quartz polymorphs (micrography H. Leroux)
Recuits sur des précurseurs de
diopsides (740°C, 10j)
(irradiation)Irradiation in astrophysical environments
• SN shock waves Irradiation :
• Cosmic rays interactions particles-matter
• X-winds (photons, electrons, ions) inducing
• Solar flairs, outflows… modifications of the material
• Grain size distribution
• Lifetime
• Structure
• Composition
• Porosity
• Optical properties
• Isotopic signatures
Implantation Sputtering
Lin et al., 1994, Adv. Space Res,
20, 465Electron irradiation
Transmission
Electron
Microscope(MET)
• Irradiation and in situ characterization
(microstructure, crystallinity, composition).Electron irradiation:
Amorphization, radiolysis, chemistry
Chemical changes associated with amorphization
Phase
transition
Olivine MgO
+SiO2
1 µm
(Carrez et al. 2002)
Irradiation of MgSiO3
composition at 300 keV Carrez et al., 2001
San Carlos olivine irradiated :
Oxygen bubbles formation Differential loss of the different elements.
Structure-dependent kineticsItokawa Dust particules collected from the
Hayabusa mission
Amorphization,
In situ reduction of iron from
minerals into metallic nuggets,
Noble gas implantation…
A closer look at experimental data
may help to quantitatively describe
the space weathering Noguchi et al., Science, 2011Electron irradiation of OM’s
Polyethylene terephthalate (PET) is a
semicrystalline symetrical arrangement
of aromatic groups and aliphatic chains
Comprehensive description of
irradiation-induced modifications of the
IOM in relation with their D/H
signatures
PhD thesis of Boris Laurent, UMET in coll. MNHN
http://umet.univ-lille1.fr/Projets/FrIHIDDA/ 12 keV, e-, PET, 2500 nmElectron irradiation of OM’s
IR spectra of electron-irradiated PET at 30 keV
EPR spectroscopy of irradiated PET
showing the appearance of mono- and
biradicals
IR image of the growing band at 1600 cm-1 in
electron-irradiated PET at 30 keV Laurent et al. coming LPSCElectron irradiation of OM’s:"
Waiting for MarcoPolo-R…
D/H ratios of irradiated PET as a function of Dose:
Several hundreds permil fractionation, attainment of a steady state (??)
For a detailed study of the correlations between irradiation, catalysis,
structural and D/H modification of OM, please attend the coming LPSC
Laurent et al. coming LPSCThanks to • H. Leroux, B. Laurent, J. Gillot, UMET • L. Rémusat, F. Robert, MNHN • H. Vezin, LASIR
Experimental approach of dust
processing in protoplanetary disks and
comparison with returned samples
Mathieu Roskosz
Workshop MarcoPolo-R, December 2012, CNES-Hqs
Mathieu.roskosz@univ-lille1.frExemple 1: composition enstatite
Cristallisation sous la température de transition vitreuse
a b
c
200 nmDurée de vie de l’assemblage Forsterite+SiO2
120
580MPa 1 Wt% H2O 25
450 MPa
100 1000°C nominally anhydrous
210 MPa 0,1 Wt% H2O 210 MPa
Thickness ^2 (microns)
20 1 Wt% H2O 1000°C
Thickness^2 (microns)
80
15
60
40 10
20
5
0
0 10 20 30 40 50 60 70 80 90 100
time (h) 0
0 10 20 30 40 50 60 70 80 90 100
time (h)
700
1450°C
600 1400°C
1350°C
Fo+SiO2 DOIT se transformer en
enstatite
thickness^2 (microns)
500
400
0 Wt% H2O
1 bar
La vitesse de cette transformation
300
dépend fortement de P, H2O, et T
200
100
Que se passe-t-il à basse P, T et
0
0 20 40 60 80 100 120
sans eau (sous 1000°C) ?
time (h)
Data from Yund, 97, CMP; Fisler et al., 97, PCMDurée de vie de l’assemblage Forsterite+SiO2
Recuits sur un assemblage de fin grains de forsterite encapsulés dans une
matrice de silice pure formée par sol-gel.
Recuits à 1000°, 1100° et 1250°C jusqu’à 1 mois
Les extrapolations arrhéniennes des données HP ou HT avec et sans eau
prédisent une vitesse de croissance de la couche d’enstatite d’au moins
10-11m.s-1 à 1100°CDurée de vie de l’assemblage Forsterite+SiO2
500 nm 200 nm
Moins de 4 10-16 m.s-1
Pourtant la diffusion cationique
opère (murissement des textures) En l’absence de pression de
confinement et d’eau
La nucléation d’enstatite est L’assemblage Fo+SiO2 peut être
inhibée à l’interface préservé à TMineralogical zoning
Conclusion et applications
Mineralogical zoning
Irradiation in astrophysical environments
• Nature des particules (photon, électrons, ions)
• Flux des particules (particules cm-2 s-1)
• Fluence (particules cm-2)
• Spectre d’énergie (eV, keV or MeV ?)
Stone et al., 2008, Adv. Space Res, 454, 71 Lin et al., 1994, Adv. Space Res, 20, 465Irradiation par des ions: exemple 2/3
amorphisation Conditions
experimentales:
He sur olivine
Energie: 4 keV
5 1016 ions/cm2 1017 ions/cm2
Porosité des
poussières
Implantation
Implantations de gaz
rares
Réduction de la taille
des poussières dans
l’ISM ?
Surpression, fracturation
Demyk et al., 2001,
5 1017 ions/cm2 1018 ions/cm2 Carrez et al., 2002Le grand recyclage stellaire
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