Analyse par faisceaux d ions

Transcription

1 éminaire INTN aclay 24 octobre 2007, aclay Analyse par faisceaux d ions appliqués à l Art et à l Archéologie Thomas Calligaro Centre de recherche et de restauration des musées de France CNR UMR 171 Palais du Louvre - Paris - France

2 Plan de la présentation Pourquoi des faisceaux pour l él étude du patrimoine culturel Faisceaux d ions d en Arts et Archéologie Principe de l analyse l par faisceaux d ionsd PIXE, R, ERDA, NRA AGLAE et le faisceau extrait à l air Autres laboratoires Exemples d applicationd Datation indirecte par l analyse l élémentaire : authentification d une d peinture Indentification de matériaux and détermination de provenance Les yeux de la déesse d Ishtar ibliographie et perspectives

3 Principales motivations de l él étude du patrimoine culturel par des méthodes m scientifiques Diagnostics rapides, études de service acquisition (authentification( authentification) préalablement à une restauration avant exposition Programmes de recherche à long terme archéometrie : étude des technologies anciennes et de la provenance science de la conservation : comprendre la technique des artistes conservation préventive : étude des mécanismes d altération

4 Démarche et contraintes Problmatiques en Art & Archéologie Contraintes identification des materiaux analyse des constituants majeurs provenance des materiaux éléments traces Processus d altération caractérisation risation de la surface Objets précieux Pas de prélèvemement méthodes non-invasives Pas de dommage méthodes non-destructives composition inconnue méthodes panoramique composition non-homog homogène lateralement sonde de faible diamètre En profondeur profilage d éléments en profondeur

5 Principe de l analyse l par faisceaux d ions d (IA) intéraction d ions légers (p, d, α) d une énergie de qq MeV avec les atomes de la cible selon la distance d approche au noyau, interaction atomique (avec les electrons) ou interaction nucléaire produits d intéraction recueillis et triés selon leur énergie (spectre) énergie élément (analyse qualitative) intensité du signal concentration (analyse quantitative)

6 Fundamentals of ion beam methods eryllium : 9 e(p,αγ) 6 Li 3562 kev e- expelled electron target atoms Lithium : 7 Li(p,p γ) 7 Li 477 kev Fluorine : 19 F(p,p γ) 19 F 197 kev 3-MeV protons γ-rays rays X-rays accelerator HPGe detector i(li) detector

7 Fundamentals of ion beam analysis PIXE : particle induced X-ray emission E x = k(z-1) 2 Moseley law Z range 10 < Z < 92 incident beam 3-MeV protons low current ~1 na no damage high sensitivity ~ 1 µg/g probing depth 1-50 µm microprobe Ø µm 3-step atomic process : inner-shell ionisation electronic rearrangement X-ray emission Applications bulk analysis of materials determination of trace elements

8 PIXE spectra of a medieval glass

9 Fundamentals of ion beam analysis R : Rutherford ackscattering pectrometry K=E/E 0 = f(m, depth) kinematic factor K = [(M 22 -M 12 sin 2 θ) 1/2 +M 1 cos θ] 2 /[M 1 +M 2 ] 2 σ ~ Z 12 Z 2 2 E -2 [sin(θ/2)] -4 incident beam : 3-MeV 4 He or protons suitable for profiling high Z elements in a low Z matrix probing depth 1-10 µm purely electrostatic elastic process Applications layers at the surface of materials example : guilding of jewels

10 R analysis of metallic lustre of islamic ceramics He ++ beam 3 MeV Energy kev Energy [kev] d30m a018.a3 im ulated Counts O i Ag Pb Channel

11 K = M p M r 4 p r ( M + M ) cos 2 2 Θ Fundamentals of ion beam analysis ERDA : Elastic recoil detection analysis K=E/E 0 = f(m, depth) kinematic factor Κ = 4 Μ 1 Μ 2 [Μ 1 +Μ 2 ] -2 cos 2 θ Μ 1 >Μ 2 M 1 Z 1 σ ~ Z 12 Z 2 2 E -2 [sin(θ/2)] -4 θ M2 Z2 θ purely electrostatic elastic process incident beam : 3-MeV 4 He suitable for profiling elements lighter than projectile very low Z element (mainly hydrogen) probing depth 1-5 µm Applications hydration of the surface of materials example : weathering of glass

12 ERDA analysis of H in antique emeralds He ++ beam 3 MeV Yield Mica lab Mica Troc Rubis Colombie Habachtal MAN MAN MAN Channel

13 incident particle = projectile Principle of nuclear reactions target nucleus a X b θ emitted particle = ejectile a + X X(a,b)Y Y + b φ Y residual nucleus

14 Fundamentals of ion beam analysis NRA : Nuclear Reaction Analysis incident beam : 1 H, 2 H or 3 He of a few MeV PIGE : γ-ray detection E γ = f(isotope) bulk composition for 1<Z<11 complementary to PIXE high sensitivity ~ ppm level examples of nuclear reaction 1 H( 19 F,αγ) 16 O fluorine profiling 19 F( 1 H,αγ) 16 O hygrogen profiling 16 O( 2 H,p) 17 O oxygen profiling NRA : particle detection E p = f(isotope, depth) profiling low Z elements in a high Z matrix C,N,O composition of bronze patina weathering of glasses dating archaeological flint tools by F profiling

15 non-resonant ion-gamma reactions (PIGE) bulk analysis element reaction Eγ kev yield /µc/r applications 3.5-MeV protons lithium 7 Li(p,p γ) 7 Li emeralds beryllium 9 e(p,αγ) 6 Li emeralds fluorine 19 F(p,p γ) 19 F bone sodium 23 Na(p,p γ) 23 Na glass silicon 28 i(p,p γ) 28 i glass copper 28 Cu(p,p γ) 28 Cu bronze, gold silver 28 Ag(p,p γ) 28 Ag gold gold 28 Au(p,p γ) 28 Au gold 1.8 MeV deuterons carbon 12 C(d,pγ) 13 C copper alloys nitrogen 14 N(d,pγ) 15 N copper alloys oxygen 16 O(d,pγ) 17 O copper alloys sulfur 32 (d,pγ) copper & gold alloys

16 E gamma (kev) coups F 197 kev Na 439 kev Li 478 kev Al 843 kev Al 1014 kev Na 1634 kev i 1778 kev e 3562 kev

17 resonant ion-gamma reactions depth profiling element Reaction E r MeV Eγ ΜeV R µm R µm applications H 1 H( 15 N, αγ) 12 C obsidian dating H 1 H( 19 F, αγ) 16 O glass weathering F 19 F(p, αγ) 16 O flint dating Na 23 Na(p,αγ) 20 Ne glass weathering 32 (p,p γ) bronze patina ion-ion reactions depth profiling Element Reaction E R µm R µm applications C 12 C(d,p) 13 C bronze, gold surface N 14 N(d,p) 15 N bronze patina O 16 O(d,p) 17 O bronze patina 32 (d,p) gold soldering Na 23 Na(p,α) 20 Ne glass weathering

18 pecificity of IA techniques Advantages multi-elemental including light elements non-destructive no sampling sensitivity to trace elements (µg/g) highly quantitative (1-3 %) several techniques combined simultaneously concentration profiles (R, NRA) surface analysis (up to 1-30 µm) Disadvantages no information about the chemical state (XP, XA) no structural information (XRD, IR, Raman) near surface (1 30 µm) (problems with altered objects) expensive large scale facility

19 Usefulness of IA for Archaeometry Materials identification analysis of major elements by PIXE and PIGE Materials provenance (sources of raw materials and trade routes) analysis of trace elements by PIXE Artistic or manufacture technology patial distribution required: lateral by µpixe, in depth by R

20 Usefulness of IA for Conservation science Assessment of state of conservation of museum objects study of alteration mechanisms affecting the surface depth profiling by R and NRA Preventive conservation monitoring the museum environment (air) PIXE analysis of aerosols collected in musems R analysis of monitors

21 Localisation de l accélérateur AGLAE

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23 charged particles in air : the external beam enefits direct analysis of artefacts any shape and any size no sampling no charging, no preparation no heating, reduced damage easy sample positioning 120-mm air path for 3-MeV 3 p thin exit foil

24 extending the range of measured elements the multi-detector set-up sample He flow L entrance window absorber energy range «low energy» L -detector 0.25 µm boron nitride 1 µm carbon He atmosphere «high energy» H - detector 6 µm e 100 µm aluminum 0,6-20 kev 5-40 kev H element range solid angle major elements Na-Fe trace elements Ca-U 1 msr 100 msr J.D. MacArthur et al at Florence, Italy

25 European networks for the study of cultural heritage with ion beams COT action G8 non-destructive analysis and testing of museum objects cooperation between 20 European countries representatives : 50/50 scientists and curators/archaeologists archaeologists meetings and short-term term missions Eu-ARTECH Access, research and technology for the conservation of the European Cultural Heritage networking of 13 conservation labs and institutions Transnational access to : AGLAE accelerator-based facility MOLA,, a set of mobile instruments for «on the field» measurements.

26 Laboratory Accelerator type Experimental Main research fields elgium Liège Cyclotron setups external beam paintings glasses elgium Namur 2 MV tandem external µprobe gold metallurgy Finland Helsinki 5 MV tandem external beam gold metallurgy paintings France Paris C2RMF 2 MV tandem external µprobe ceramics stones gems metals glasses Germany erlin Cyclotron external beam enamels glazes manuscripts paintings metals Germany Rossendorf 5 MV tandem external µprobe bones paintings drawings glasses Greece Athens 5 MV tandem external beam metals ceramics Hungary udapest 2 MV Van de Graaff external beam manuscripts bronzes Hungary Debrecen 5 MV Van de Graaff µprobe paintings gemstones glasses Italy Florence 3 MV Van de Graaff external µprobe manuscripts ceramics Mexico UNAM 2 MV tandem external µprobe stones, pigments, jewellery lovenia Ljubljana 2 MV tandem external µprobe coins stones pain Madrid 5 MV tandem external µprobe ceramics pain evilla 2 MV tandem external µprobe jewellery ceramics weden Lund 3 MV tandem external µprobe manuscripts glasses yria Damas 3 MV tandem vacuum chamber Lebanon eyruth 1.7 MV tandem vacuum chamber ceramics UA Tempe 2 MV tandem external beam ceramics China hanghai 3 MV tandem external beam ceramics manuscripts metals Japan Tokyo 2 MV tandem external beam ceramics ingapore 2.5 MV Van de Graaff µprobe bones gemstones Taiwan Taipei 3 MV tandem external beam coins Australia Lucas 3 MV Van de Graaff external beam ceramics obsidians Heights outh Africa Faure 5 MV Van de Graaff external beam ceramics

27 First application of IA : authentication of a painting by PIXE

28 Analysis of The (presumed)) portrait of ernard Palissy French scientist and artist of the Renaissance ( ) 1589) Painting supposedly representing. Palissy kiln used by Palissy for making ceramics Precisely unearthed during the building of the laboratory

29 PIXE analysis of paint layers Dark background contains chromium green PbCrO4 available after 1850 grey collar contains Naples yellow lead antimoniate only used after 1650 This painting is probably a forgery

30 econd example of application of IA : Identification and provenancing of gemstones

31 Ishtar s eyes tatuette exhibited in the Louvre Dated to the Parthian period (1 (1 st C 2 nd AD) st C Likely representing Ishtar, the famous mesopotamian mother goddess (Astarté or Venus) Discovered in 1863 in Hillah,, close to abylon

32 Materials identification : Ishtar s statuette was placed in the external beam

33 PIXE spectra recorded on one eye 1e5 Al K high energy X-ray detector spectrum O K Ti K V K Cr K Fe K low energy X-ray detector spectrum Ga K 1000 counts X-ray energy (kev)

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35 Afghanistan abylon India 2 urma VietNam Thailand rilank India 1 Cambodia ri Lanka Map of Middle East and Asia : sources of rubies

36 Trace element fingerprint of rubies from Ishtar and various deposits Chromium (ppm) V V V A A A X X X X X X VV X V V V V group I urma Vietnam A tatuette of Ishtar X A A A A A K K A V V V A A A A A K V group II Afghanistan rilanka Vietnam M M M TMM MM M I I I T CTC I C K MM MM I I TT T I I T T I T T TM M TT M I MM T T M M I group III Thailand Cambodia Kenya Madagascar India Iron(ppm)

37 Afghanistan abylon India 2 urma VietNam Thailand rilank India 1 Cambodia ri Lanka Map of Middle East and Asia : sources of rubies

38 Proof of authenticity of the statuette Original report of Mr P. Delaporte,, French consul at agdad who discovered the statuette Document written at Hillah, close to abylon January 21, 1863

39 Results The eyes and the navel of Ishtar are not made of red glass, nor red garnets, as previously reported, but rather proved to be fine rubies. According to the age of the statuette, this is the most ancient rubies found in Middle-East. Evidence of a gem route between outh-east Asia and Mesopotamia during the 1 st century C.

40 Conclusion et perspectives Les techniques IA procurent une moisson d information sur les matériaux des oeuvres d art et d archéologie faisceau extrait spécialement adapté à l étude des oeuvres du patrimoine précieuses et fragiles combination PIXE-PIGE la plus courante intérêt croissant pour des techniques basés sur les particules chargées R, ERDA and NRA depth information versatilité du faisceau extrait permet des expériences particulières: par ex. Mesure en temps réel et en atmosphère contrôlée Dans le futur PIXE concurrencé par techniques XRF Portable, ICP/M, Raman Combinaison PIXE-R (NRA) n a pas encore d équivalent

41 PIXE ibliographie PIXE a novel technique for elemental analysis, Wiley Wiley,, 1988 Particle Induced X-Ray Emission pectrometry (PIXE), Wiley R, NRA, PIGE Ion eams for Material Analysis, Academic Academic Press,, 1989 Wiley,, 1995 Handbook of Modern Ion eam Analysis. Material Research ociety, 1995 Fundamentals of urface and Thin Film Analysis, Elsevier, 1986 Application à l archéometrie Ion beam techniques in archaeology and the arts Nuclear cience Applications, Intern. Workshop on ion eam Analysis in the Arts and Archaeology Nuclear Instruments & Methods Ion beam study of art and archaeological objects COT G1, Official Publications of the European Communities Particle induced X-ray Emission Modern Analytical Methods in Art and Achaeology, Chemical Analysis, Wiley,, 2000 Ion beam microanalysis Non-Destructive Microanalysis of Cultural Heritage Materials,, Elsevier, 2004

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