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Your search keyword '"Sebastian Schöder"' showing total 11 results
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11 results on '"Sebastian Schöder"'

1. Anthropogenic modification of a giant ground sloth tooth from Brazil supported by a multi-disciplinary approach

Author

Thaís R. Pansani, Loïc Bertrand, Briana Pobiner, Anna K. Behrensmeyer, Lidiane Asevedo, Mathieu Thoury, Hermínio I. Araújo-Júnior, Sebastian Schöder, Andrew King, Mírian L. A. F. Pacheco, and Mário A. T. Dantas

Subjects
Pleistocene, South America, Zooarchaeology, Megafauna, Tooth artifact, Medicine, Science
Abstract

Abstract Identifying evidence of human modification of extinct animal remains, such as Pleistocene megafauna, is challenging due to the similarity of anthropogenic and non-anthropogenic taphonomic features observed under optical microscopy. Here, we re-investigate a Late Pleistocene ground sloth tooth from northeast Brazil, previously suggested as human-modified based only on optical observation. To characterize the macro- and micro-morphological characteristics of the marks preserved in this tooth and evaluate potential human modification, we used stereomicroscope and scanning electron microscopy (SEM) supplemented by energy dispersive spectroscopy (EDS), UV photoluminescence (UV/PL), synchrotron-based X-ray fluorescence (SR-XRF), and synchrotron micro-computed tomography (SR-µCT). These methods allowed us to discriminate non-anthropogenic taphonomic features (root and sedimentary damage), anthropogenic marks, and histological features. The latter shows the infiltration of exogenous elements into the dentine from the sediments. Our evidence demonstrates the sequence of anthropogenic and non-anthropogenic taphonomic modification of this tooth and supports its initial intentional modification by humans. We highlight the benefits of emerging imaging and spectral imaging techniques to investigate and diagnose human modification in fossil and archaeological records and propose that human modification of tooth tissues should be further considered when studying possibly anthropogenically altered fossil remains.

Published
2024
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2. X-ray Synchrotron Radiation to Look at Pigments in Antiquities: Overview and Examples

Author

Alessandra Gianoncelli, Sebastian Schöder, Jasper R. Plaisier, Maura Fugazzotto, Germana Barone, Alfonsina Russo, Paolo Mazzoleni, and Simona Raneri

Subjects
SR-µXRF, SR-µXANES, SR-XRD, pigments, ceramics, Archaeology, CC1-960
Abstract

The recent upgrading of synchrotron radiation (SR) sources has favored, in the last few years, the construction and design of beamlines optimized for the study of cultural heritage materials, which may require ad hoc setups, specific spatial resolutions, and detection limits. In the field of cultural heritage, integrated approaches combining different techniques are often required, even at large facilities, where some beamlines offer the possibility of performing different types of measurements at the same point of analysis, complementing preliminary information usually obtained by conventional laboratory and/or portable in situ methods. An overview of the last ten years of synchrotron applications for the study of pigments is given, with discussion of upstream and downstream challenges to methods and techniques. The possibilities offered by the synchrotron techniques are illustrated by a case study of a particular class of painted ceramics, as an example of different research questions that are solved by a combination of SR-based methods.

Published
2024
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3. X-ray Fluorescence Spectroscopy of Picrolite Raw Material on Cyprus

Author

Theodora Moutsiou, Demetrios Ioannides, Andreas Charalambous, Sebastian Schöder, Sam M. Webb, Mathieu Thoury, Vasiliki Kassianidou, Zomenia Zomeni, and Christian Reepmeyer

Subjects
picrolite, X-ray fluorescence, synchrotron microspectroscopy, sourcing, Cyprus, Archaeology, CC1-960
Abstract

Picrolite artefacts comprise some of the most distinctive material remains in the prehistory of the island of Cyprus, in the Eastern Mediterranean. Picrolite exploitation dates from at least 12,000 years ago for the manufacture of personal ornaments and items with a symbolic function. It is commonly assumed that picrolite nodules were collected in secondary deposits on an ad hoc basis. This narrative, however, ignores the fact that picrolite carriers can only be found in very specific locations on the island, discrete from each other. Here we report initial outcomes of the application of handheld portable X-ray fluorescence (HHpXRF) and synchrotron-based X-ray fluorescence spectroscopy (SR-μXRF) to the analysis of picrolite raw materials performed at the newly opened PUMA beamline of the SOLEIL Synchrotron Radiation Facility. Our work refines the basic characteristics of the elemental constituents of the picrolite raw material and highlights key micro-structural differences between two distinct source regions on the Troodos Massif in western Cyprus. Picrolite source characterisation is expected to contribute significant new knowledge to the study of rare raw material consumption, prehistoric social organisation, networking and possible long-distance exchange of this idiosyncratic raw material within and beyond the island’s geographic boundaries.

Published
2022
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4. Synchrotron X-ray Microprobes: An Application on Ancient Ceramics

Author

Alessandra Gianoncelli, George Kourousias, Sebastian Schöder, Antonella Santostefano, Maëva L’Héronde, Germana Barone, Paolo Mazzoleni, and Simona Raneri

Subjects
X-ray fluorescence, synchrotron radiation, µXRF, µXANES, black gloss, ancient ceramics, Technology, Engineering (General). Civil engineering (General), TA1-2040, Biology (General), QH301-705.5, Physics, QC1-999, Chemistry, QD1-999
Abstract

Synchrotron X-ray µ- and nano-probes are increasingly affirming their relevance in cultural heritage applications, especially in material characterization of tiny and complex micro-samples which are typical from archaeological and artistic artifacts. For such purposes, synchrotron radiation facilities are tailoring and optimizing beamlines and set-ups for CH, taking also advantages from the challenges offered by the third-generation radiation sources. In ancient ceramics studies, relevant information for the identification of production centers and manufacture technology can be obtained in a non-invasive and non-destructive way at the micro-sample level by combining different SR based methods. However, the selection of appropriate beamlines, techniques and set-ups are critical for the success of the experiments. Fine and varnished wares (e.g., Attic and western-Greek colonial products) are an excellent case study for exploring challenges offered by synchrotron X-ray microprobes optimized to collect microchemical and phase-distribution maps. The determination of provenance and/or technological tracers is relevant in correctly classifying productions, often based only on ceramic paste, gloss macroscopic features or style. In addition, when these vessels are preserved in Museums as masterpieces or intact pieces the application of non-invasive approach at the micro sample is strictly required. Well-designed synchrotron µXRF and µXANES mapping experiments are able providing relevant clues for discriminating workshops and exploring technological aspects, which are fundamental in answering the current archaeological questions on varnished Greek or western-Greek colonial products.

Published
2021
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6. Practical advances towards safer analysis of heritage samples and objects

Author

Loïc Bertrand, Sebastian Schöder, Ineke Joosten, Samuel M. Webb, Mathieu Thoury, Thomas Calligaro, Étienne Anheim, Aliz Simon, Photophysique et Photochimie Supramoléculaires et Macromoléculaires (PPSM), Institut de Chimie du CNRS (INC)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Ecole Normale Supérieure Paris-Saclay (ENS Paris Saclay), Synchrotron SOLEIL (SSOLEIL), Centre National de la Recherche Scientifique (CNRS), Cultural Heritage Agency of the Netherlands, SLAC National Accelerator Laboratory (SLAC), Stanford University, Institut photonique d'analyse non-destructive européen des matériaux anciens (IPANEMA), Muséum national d'Histoire naturelle (MNHN)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Centre National de la Recherche Scientifique (CNRS)-Ministère de la Culture (MC), Centre de recherche et de restauration des musées de France (C2RMF), Ministère de la Culture et de la Communication (MCC)-Centre National de la Recherche Scientifique (CNRS), Centre de Recherches Historiques (CRH) _ Unité Mixte de Recherches (UMR 8558 CNRS / EHESS) (CRH (UMR 8558 CNRS / EHESS)), École des hautes études en sciences sociales (EHESS)-Centre National de la Recherche Scientifique (CNRS), International Atomic Energy Agency [Vienna] (IAEA), ANR-17-EURE-0021,PSGS-HCH,Paris Seine Graduate School of Humanities Creation Heritage(2017), European Project: 654028,H2020 Pilier Excellent Science,H2020-INFRAIA-2014-2015,IPERION CH(2015), and European Project: 871034,H2020,H2020-INFRAIA-2018-2020,IPERION HS(2020)

Subjects
Radiation damage, [SPI]Engineering Sciences [physics], Synchrotron radiation, Ion beam analysis, Ancient materials, [CHIM]Chemical Sciences, Cultural Heritage, Spectroscopy, Analytical Chemistry, [SHS]Humanities and Social Sciences
Abstract

International audience; In recent years, we have seen a significant increase in interest in the effects of irradiation used for analytical purposes on art, archaeological, palaeontological and palaeoenvironmental samples and objects. Among the main trends regarding ionising radiations used in X-ray, UV and ion beam experiments, we have observed a greater consistency in the description of the effects of irradiation, a number of quantitative studies, while several works studied in depth the corresponding chemical mechanisms and kinetics. We have also observed the development of analytical strategies and dedicated instruments to better detect and limit the effects of irradiation in real experiments on ancient samples and objects. Emerging trends include detailed mechanistic studies on specific systems, the development of statistical methods to reduce the doses required to study samples, and the development of early warning systems capable of feeding back into the experiment while an acquisition is in progress.

Published
2023
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8. X-ray irradiation effects on Egyptian blue and green pigments

Author

Marie Godet, Laurent Binet, Sebastian Schöder, Lucile Brunel-Duverger, Mathieu Thoury, Loïc Bertrand, Institut photonique d'analyse non-destructive européen des matériaux anciens (IPANEMA), Muséum national d'Histoire naturelle (MNHN)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Centre National de la Recherche Scientifique (CNRS)-Ministère de la Culture (MC), Institut de Recherche de Chimie Paris (IRCP), Ecole Nationale Supérieure de Chimie de Paris - Chimie ParisTech-PSL (ENSCP), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Ministère de la Culture (MC), Synchrotron SOLEIL (SSOLEIL), Centre National de la Recherche Scientifique (CNRS), Centre de recherche et de restauration des musées de France (C2RMF), Ministère de la Culture et de la Communication (MCC)-Centre National de la Recherche Scientifique (CNRS), Photophysique et Photochimie Supramoléculaires et Macromoléculaires (PPSM), Institut de Chimie du CNRS (INC)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Ecole Normale Supérieure Paris-Saclay (ENS Paris Saclay), and European Project: 654028,H2020 Pilier Excellent Science,H2020-INFRAIA-2014-2015,IPERION CH(2015)

Subjects
[SHS.ARCHEO]Humanities and Social Sciences/Archaeology and Prehistory, [CHIM.MATE]Chemical Sciences/Material chemistry, [SHS.MUSEO]Humanities and Social Sciences/Cultural heritage and museology, [CHIM.RADIO]Chemical Sciences/Radiochemistry, Spectroscopy, Analytical Chemistry
Abstract

International audience; Egyptian blue and green are among the oldest synthetic pigments produced by humanity. The two pigments are complex multi-phase copper-based systems synthesised with different protocols from the same raw materials. Since the 2000s, synchrotron X-ray techniques have provided significant new insights on their chemistry and microstructure. However, the potential impact of high flux irradiation of these pigments has not yet been studied despite the fact that it can lead to visual discoloration and less readily observable alterations such as defects formation or redox changes. In this work, we investigate the effects of synchrotron X-ray irradiation on Egyptian blue and green samples. Radiation-induced effects are monitored after irradiation at increasing doses using electron paramagnetic resonance (EPR) spectroscopy at temperatures of 290 K and 30 K. The cupric ion (Cu2+) is in D4h axial geometry in Egyptian blue and in disordered geometry in Egyptian green, which makes the two pigments very easily identifiable by EPR. Egyptian green samples are found to be much more sensitive to X-rays than Egyptian blue. In particular, a browning of the green samples is observed from the lowest doses tested while no color change is detected for the blue ones. Three types of radiation-induced defects are detected after irradiation: E′, non-bonding oxygen hole and aluminum hole centers. Correlations between defect intensity and dose are calculated. Archaeological and modern pigments (whether blue or green) do not show the same reactivity to X-rays, which opens the prospect of using radiation-induced defects as a marker of their history.

Published
2022
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9. Short- and long-term effect of radiation damage in cotton paper

Author

Anne-Laurence Dupont, Alice Gimat, Sebastian Schöder, Mathieu Thoury, Sabrina Paris-Lacombe, Centre de Recherche sur la Conservation (CRC ), Muséum national d'Histoire naturelle (MNHN)-Ministère de la Culture et de la Communication (MCC)-Centre National de la Recherche Scientifique (CNRS), Centre de Recherche pour la Conservation des Collections (CRCC), Muséum national d'Histoire naturelle (MNHN)-Ministère de la Culture et de la Communication (MCC)-Centre National de la Recherche Scientifique (CNRS)-Muséum national d'Histoire naturelle (MNHN)-Ministère de la Culture et de la Communication (MCC)-Centre National de la Recherche Scientifique (CNRS), Synchrotron SOLEIL (SSOLEIL), Centre National de la Recherche Scientifique (CNRS), Dupont, Anne-Laurence, and Synchrotron SOLEIL, L'Orme des Merisiers, Saint-Aubin BP 48, 91192 Gif-sur-Yvette Cedex, France.

Subjects
[SHS.MUSEO] Humanities and Social Sciences/Cultural heritage and museology, [CHIM] Chemical Sciences, [CHIM]Chemical Sciences, [SHS.MUSEO]Humanities and Social Sciences/Cultural heritage and museology
Abstract

International audience; The analysis of cultural heritage artefacts with ionizing radiation has rapidly increased in popularity over the last decades - in particular at synchrotron sources - leading to many fascinating new discoveries. However, the damage inflicted to the materials under study during the irradiation is still largely unknown. Organic samples, such as paper, are especially vulnerable to degradation by X-rays. In this work we quantify the radiation damage on a molecular level and show that the chemical reactions triggered promote cellulose degradation and continueto alter the material for several months after the irradiation took place.

Published
2021

10. Short- and Long-Term Effects of X-ray Synchrotron Radiation on Cotton Paper

Author

Mathieu Thoury, Sebastian Schöder, Sabrina Paris-Lacombe, Mauro Missori, Anne-Laurence Dupont, Alice Gimat, Centre de Recherche sur la Conservation (CRC ), Muséum national d'Histoire naturelle (MNHN)-Ministère de la Culture et de la Communication (MCC)-Centre National de la Recherche Scientifique (CNRS), Synchrotron SOLEIL (SSOLEIL), Centre National de la Recherche Scientifique (CNRS), Institut photonique d'analyse non-destructive européen des matériaux anciens (IPANEMA), and Muséum national d'Histoire naturelle (MNHN)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Centre National de la Recherche Scientifique (CNRS)-Ministère de la Culture (MC)

Subjects
Materials science, Polymers and Plastics, Analytical chemistry, Synchrotron radiation, Bioengineering, Context (language use), 02 engineering and technology, Radiation, 010402 general chemistry, 01 natural sciences, law.invention, Biomaterials, OXIDATIVE-DEGRADATION, CELLULOSE DEGRADATION, RESIDUAL CHROMOPHORES, PHYSICAL-PROPERTIES, GAMMA-IRRADIATION, FLUORESCENCE, SPECTROSCOPY, WATER, IDENTIFICATION, MITIGATION, law, Materials Chemistry, Irradiation, Spectroscopy, Chromatography, High Pressure Liquid, [PHYS]Physics [physics], X-Rays, 021001 nanoscience & nanotechnology, Synchrotron, 0104 chemical sciences, Radiography, Chromatography, Gel, 0210 nano-technology, Luminescence, Refractive index, Synchrotrons
Abstract

International audience; X-ray analytical techniques are increasingly being used to study manuscripts and works of art on paper, whether with laboratory equipment or synchrotron sources. However, it is difficult to anticipate the impact of X-ray photons on paper- and cellulose-based artifacts, particularly due to the large variety of their constituents and degradation levels, and the subsequent material multiscale heterogeneity. In this context, this work aims at developing an analytical approach to study the modifications in paper upon synchrotron radiation (SR) X-ray radiation using analytical techniques, which are fully complementary and highly sensitive, yet not frequently used together. At the molecular scale, cellulose chain scissions and hydroxyl free radicals were measured using chromatographic separation techniques (size-exclusion chromatography-multiangle laser light scattering-differential refractive index (SEC-MALS-DRI) and reversed-phase high-performance liquid chromatography-fluorescence detector-diode array detector (RP-HPLC-FLD-DAD)), while the optical properties of paper were characterized using spectroscopy (UV luminescence and diffuse reflectance). These techniques showed different sensitivities toward the detection of changes. The modifications in the cellulosic material were monitored in real time, within a few days, and up to 2 years following the irradiation to define a lowest observed adverse effect dose (LOAED). As paper is a hygroscopic material, the impact of the humidity in the environment was studied using this approach. Three levels of moisture content in the paper, achieved by conditioning the samples and irradiating them at different relative humidities (RHs), were studied (0, 50, 80% RH). It was shown that very low moisture content accelerated molecular and optical modification

Published
2020
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11. A new 3D positioner for the analytical mapping of non-flat objects under accelerator beams

Author

Thomas Calligaro, Luis Arean, Claire Pacheco, Quentin Lemasson, Laurent Pichon, Brice Moignard, Clotilde Boust, Loïc Bertrand, Sebastian Schöder, Mathieu Thoury, Rosta, L., László Szentmiklósi, Janos Füzi, Zoltan László, Victor Heirich, Centre de recherche et de restauration des musées de France (C2RMF), Centre National de la Recherche Scientifique (CNRS)-Ministère de la Culture et de la Communication (MCC), Institut de Recherche de Chimie Paris (IRCP), Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Ecole Nationale Supérieure de Chimie de Paris - Chimie ParisTech-PSL (ENSCP), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Ministère de la Culture (MC), New AGLAE - CNRS/Ministère de la Culture/ENSCP (new AGLAE), Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Institut photonique d'analyse non-destructive européen des matériaux anciens (IPANEMA), Muséum national d'Histoire naturelle (MNHN)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Centre National de la Recherche Scientifique (CNRS)-Ministère de la Culture (MC), Synchrotron SOLEIL (SSOLEIL), Centre National de la Recherche Scientifique (CNRS), Budapest Neutron Centre (BNC-RISP), Janos Bolyai Research Fellowship, Hungarian Academy of Sciences, Project No. 124068, National Research, Development and Innovation Fund of Hungary, European Project: 654028,H2020 Pilier Excellent Science,H2020-INFRAIA-2014-2015,IPERION CH(2015), Zelverte, Marine, Integrated Platform for the European Research Infrastructure ON Cultural Heritage - IPERION CH - - H2020 Pilier Excellent Science2015-05-01 - 2019-04-30 - 654028 - VALID, Ministère de la Culture et de la Communication (MCC)-Centre National de la Recherche Scientifique (CNRS), Ecole Nationale Supérieure de Chimie de Paris - Chimie ParisTech-PSL (ENSCP), and Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Ministère de la Culture (MC)

Subjects
[CHIM.MATE] Chemical Sciences/Material chemistry, [SHS.ARCHEO] Humanities and Social Sciences/Archaeology and Prehistory, Hexapod, [SHS.ARCHEO]Humanities and Social Sciences/Archaeology and Prehistory, Ion beam imaging, [CHIM.MATE]Chemical Sciences/Material chemistry, [SPI.MAT] Engineering Sciences [physics]/Materials, [SHS.ART]Humanities and Social Sciences/Art and art history, 3D positioner, [SHS.MUSEO]Humanities and Social Sciences/Cultural heritage and museology, [SPI.MAT]Engineering Sciences [physics]/Materials, [SPI.AUTO]Engineering Sciences [physics]/Automatic, [SPI.AUTO] Engineering Sciences [physics]/Automatic, [SHS.MUSEO] Humanities and Social Sciences/Cultural heritage and museology, Neutron imaging, [CHIM] Chemical Sciences, Synchrotron imaging, [CHIM]Chemical Sciences, [SHS.ART] Humanities and Social Sciences/Art and art history, 3D target
Abstract

We report the development of a 3D positioner for the elemental mapping of non-flat surfaces of heritage targets and its implementation in the external beam of the AGLAE accelerator, a joint research activity of the IPERION-CH European program.The positioner operates in two steps: 1) object surface is digitized using a 3D scanner implemented in the beamline. Surface points are interpolated onto a rectangular grid suitable for beam scanning. 2) Object is scanned under the beam using X/Y/Z stages holding a hexapod robot for rotations. During scanning, target surface is positioned with the Z stage and oriented perpendicular to the beam using hexapod rotations. Areas up to 100 × 100 mm2 with a resolution of 50 µm and 30° curvature of can be mapped on objects of 200 mm and 5 kg max. System operation was tested by recording PIXE maps on the polychrome decoration of a curved porcelain pot.

Published
2019

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