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1. An electrostatic in-line charge-state purification system for multicharged ions in the kiloelectronvolt energy range

Author

Schury, Daniel, Kumar, Ajit, Méry, Alain, Chesnel, Jean-Yves, Lévy, Anna, Macé, Stéphane, Prigent, Christophe, Ramillon, Jean-Marc, Rangama, Jimmy, Rousseau, Patrick, Steydli, Sébastien, Trassinelli, Martino, Vernhet, Dominique, and Lamour, Emily

Subjects
Physics - Atomic Physics
Abstract

The performance of a newly built omega type electrostatic analyzer designed to act as an in-line charge-state purification system for ions in the keV energy range is reported. The analyzer consists of a set of four consecutive electrostatic 140{\deg} concentric cylindrical electrodes enclosed by Matsuda electrodes. This setup was recently tested and validated using $O^{5+}$ , $Ar^{9+}$ and $Xe^{20+}$ ion beams at an energy of 14 qkeV at the ARIBE facility. A resolving power of 10.5 and a transmission of 100 % of the desired charge state are measured allowing a good purification of incoming ion beams with charge states up to 10+ and a fairly good purification for charge states at least up to 20+. In comparison with other in-line solutions such as Wien filter, our system has the advantage of being purely electrostatic and therefore lacking common drawbacks as for example hysteresis.

Published
2019
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2. Mitigating space charge in time-resolved photoelectron spectroscopy to study laser-heated copper dynamics in the high fluence regime

Author

Lévy, Anna, primary, Villa, Manuel De Anda, additional, Hatifi, Mohamed, additional, Lamour, Emily, additional, Macé, Stéphane, additional, Prigent, Christophe, additional, Steydli, Sébastien, additional, Trassinelli, Martino, additional, Vernhet, Dominique, additional, Grisenti, Robert E., additional, Sobierajski, Ryszard, additional, Wawro, Andrzej, additional, Lecherbourg, Ludovic, additional, Jouin, Hervé, additional, Bouillaud, Rodrigue, additional, Descamps, Dominique, additional, Dorchies, Fabien, additional, Fedorov, Nikita, additional, Petit, Stéphane, additional, and Gaudin, Jérôme, additional

Published
2024
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3. Observation of vacancy-related polaron states at the surface of anatase and rutile TiO2 by high-resolution photoelectron spectroscopy

Author

Jackmana, Mark J., Deák, Peter, Syres, Karen L., Adell, Johan, Thiagarajan, Balasubramanian, Levy, Anna, and Thomas, Andrew G.

Subjects
Condensed Matter - Materials Science
Abstract

Defects in the surface region of a reducible oxide, as TiO2, have a profound effect on applications, while their nature is very much influenced by the possibility of small polaron formation. Here, we probe rutile (110) and anatase (101) single crystals via high-resolution ultraviolet photoelectron spectroscopy and resolve multiple components of the well-known defect state in the band gap. In rutile, we find two at VBM+2.1 eV and VBM+1.4 eV, which we assign to subsurface polaron traps and vacancy-bound states, respectively, confirming the predicted partial suppression of polaron formation at high vacancy concentration. New defects are created in situ on the anatase surface by the synchrotron beam. We assign a component at VBM+2.3 eV, which can be removed by annealing, to polaron states associated with surface oxygen vacancies. We also identify a second component at VBM+1.6 eV, which can not be removed by annealing, and is too deep to be associated with oxygen vacancies.

Published
2014

4. Probing the cosmic microwave background temperature using the Sunyaev-Zeldovich effect

Author

Horellou, Cathy, Nord, Martin, Johansson, Daniel, and Levy, Anna

Subjects
Astrophysics
Abstract

We discuss the possibility to constrain the relation between redshift and temperature of the cosmic microwave background (CMB) using multifrequency Sunyaev-Zeldovich (SZ) observations. We have simulated a catalog of clusters of galaxies detected through their SZ signature assuming the sensitivities that will be achieved by the {\it Planck} satellite at 100, 143 and 353 GHz, taking into account the instrumental noise and the contamination from the Cosmic Infrared Background and from unresolved radiosources. We have parametrized the cosmological temperature-redshift law as $T\propto (1+z)^{(1-a)}$. Using two sets of SZ flux density ratios (100/143 GHz, which is most sensitive to the parametrization of the $T-z$ law, and 143/353 GHz, which is most sensitive to the peculiar velocities of the clusters) we show that it is possible to recover the $T-z$ law assuming that the temperatures and redshifts of the clusters are known. From a simulated catalog of $\sim 1200$ clusters, the parameter $a$ can be recovered to an accuracy of 10$^{-2}$. Sensitive SZ observations thus appear as a potentially useful tool to test the standard law. Most cosmological models predict a linear variation of the CMB temperature with redshift. The discovery of an alternative law would have profound implications on the cosmological model, implying creation of energy in a manner that would still maintain the black-body shape of the CMB spectrum at redshift zero., Comment: 8 pages, 9 figures, submitted to A&A

Published
2005
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8. Surface Chemistry of Gold Nanoparticles Produced by Laser Ablation in Pure and Saline Water

Author

Lévy, Anna, primary, De Anda Villa, Manuel, additional, Laurens, Gaétan, additional, Blanchet, Valérie, additional, Bozek, John, additional, Gaudin, Jérôme, additional, Lamour, Emily, additional, Macé, Stéphane, additional, Mignon, Pierre, additional, Milosavljević, Aleksandar R., additional, Nicolas, Christophe, additional, Patanen, Minna, additional, Prigent, Christophe, additional, Robert, Emmanuel, additional, Steydli, Sébastien, additional, Trassinelli, Martino, additional, Vernhet, Dominique, additional, Veteläinen, Onni, additional, and Amans, David, additional

Published
2021
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10. Chalcogenide Films: Laser Generation of Sub‐Micrometer Wrinkles in a Chalcogenide Glass Film as Physical Unclonable Functions (Adv. Mater. 38/2020)

Author

Martinez, Paloma, primary, Papagiannouli, Irene, additional, Descamps, Dominique, additional, Petit, Stéphane, additional, Marthelot, Joël, additional, Lévy, Anna, additional, Fabre, Baptiste, additional, Dory, Jean‐Baptiste, additional, Bernier, Nicolas, additional, Raty, Jean‐Yves, additional, Noé, Pierre, additional, and Gaudin, Jérôme, additional

Published
2020
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11. Laser Generation of Sub‐Micrometer Wrinkles in a Chalcogenide Glass Film as Physical Unclonable Functions

Author

Martinez, Paloma, primary, Papagiannouli, Irene, additional, Descamps, Dominique, additional, Petit, Stéphane, additional, Marthelot, Joël, additional, Lévy, Anna, additional, Fabre, Baptiste, additional, Dory, Jean‐Baptiste, additional, Bernier, Nicolas, additional, Raty, Jean‐Yves, additional, Noé, Pierre, additional, and Gaudin, Jérôme, additional

Published
2020
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12. Assessing the Surface Oxidation State of Free-Standing Gold Nanoparticles Produced by Laser Ablation

Author

De Anda Villa, Manuel, primary, Gaudin, Jérôme, additional, Amans, David, additional, Boudjada, Fahima, additional, Bozek, John, additional, Evaristo Grisenti, Robert, additional, Lamour, Emily, additional, Laurens, Gaétan, additional, Macé, Stéphane, additional, Nicolas, Christophe, additional, Papagiannouli, Irene, additional, Patanen, Minna, additional, Prigent, Christophe, additional, Robert, Emmanuel, additional, Steydli, Sébastien, additional, Trassinelli, Martino, additional, Vernhet, Dominique, additional, and Lévy, Anna, additional

Published
2019
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13. An electrostatic in-line charge-state purification system for multicharged ions in the kiloelectronvolt energy range

Author

Schury, Daniel, primary, Kumar, Ajit, additional, Méry, Alain, additional, Chesnel, Jean-Yves, additional, Lévy, Anna, additional, Macé, Stéphane, additional, Prigent, Christophe, additional, Ramillon, Jean-Marc, additional, Rangama, Jimmy, additional, Rousseau, Patrick, additional, Steydli, Sébastien, additional, Trassinelli, Martino, additional, Vernhet, Dominique, additional, and Lamour, Emily, additional

Published
2019
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14. Depth Profiling of the Chemical Composition of Free-Standing Carbon Dots Using X-ray Photoelectron Spectroscopy

Author

Papagiannouli, Irene, primary, Patanen, Minna, additional, Blanchet, Valérie, additional, Bozek, John D., additional, de Anda Villa, Manuel, additional, Huttula, Marko, additional, Kokkonen, Esko, additional, Lamour, Emily, additional, Mevel, Eric, additional, Pelimanni, Eetu, additional, Scalabre, Antoine, additional, Trassinelli, Martino, additional, Bassani, Dario M., additional, Lévy, Anna, additional, and Gaudin, Jérôme, additional

Published
2018
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17. Adsorption Studies of p-Aminobenzoic Acid on the Anatase TiO2(101) Surface

Author

Thomas, Andrew G., Jackman, Mark J., Wagstaffe, Michael, Radtke, Hanna, Syres, Karen, Adell, Johan, Lévy, Anna, Martsinovich, Natalia, Thomas, Andrew G., Jackman, Mark J., Wagstaffe, Michael, Radtke, Hanna, Syres, Karen, Adell, Johan, Lévy, Anna, and Martsinovich, Natalia

Abstract

The adsorption of p-aminobenzoic acid (pABA) on the anatase TiO2 (101) surface has been investigated using synchrotron radiation photoelectron spectroscopy, Near Edge X-ray Absorption Fine Structure (NEXAFS) spectroscopy and Density Functional Theory (DFT). Photoelectron spectroscopy indicates that the molecule is adsorbed in a bidentate mode through the carboxyl group following deprotonation. NEXAFS spectroscopy and DFT calculations of the adsorption structures indicate ordering of a monolayer of the amino acid on the surface with the plane of the ring in an almost upright orientation. Adsorption of pABA on nanoparticulate TiO2 leads to a red shift of the optical absorption relative to bare TiO2 nanoparticles. DFT and valence band photoelectron spectroscopy suggest the shift is attributed to the presence of the highest occupied molecular orbitals in the TiO2 band gap region and the presence of new molecularly derived states near the foot of the TiO2 conduction band.

Published
2014

18. Accélération d'ions par interaction laser-matière en régime de ultra haut contraste laser

Author

Lévy, Anna, Service des Photons, Atomes et Molécules (SPAM), Commissariat à l'énergie atomique et aux énergies alternatives (CEA), Université Paris Sud - Paris XI, and Philippe Martin(philippe.martin@cea.fr)

Subjects
gradient, [PHYS]Physics [physics], wave-breaking, ionization, ions, contraste, contrast, ionisation, plasma, laser, déferlement
Abstract

Recent advances in high-intensity laser technology have opened up new perspectives in the relativistic laser-plasma interaction domain as the acceleration of ion beams to energies of several MeV. During the interaction, a part of the target electrons can reach relativistic velocities and are responsible of the generation of a dense beam of high energy ions with remarkable qualities for many applications (protontherapy, inertial fusion, probing of electric fields in dense plasmas...). Presently, one of the most important trends in research is devoted to increase the maximum attainable energy as this could further enhance the range of application. Our work demonstrate the possibility to increase the ion energy using ultra-thin foils. However, the use of this kind of target requires a laser pulse with a high temporal contrast ratio. Thanks to the implementation of a double plasma mirror, we were able to increase our laser contrast allowing the main femtosecond laser peak interact with a pre-plasma free, solid target. We present herein a complete characterization of proton beam emissions and underline the influence of the target thickness on their maximal energy. We studied each stage of the acceleration process and identified the main mechanism responsible of the electronic heating. Finally, we present a study of the rear side plasma gradient influence on the ion acceleration. Both experimental and numerical results show that owing to the presence of a density gradient the acceleration process is perturbed by ions wave breaking.; Grâce au développement récent des lasers de puissance, le domaine de l'interaction laser-matière a beaucoup évolué, ouvrant depuis quelques années, entre autres, la possibilité de générer des faisceaux d'ions à des énergies de plusieurs MeV. Soumise à de très fortes intensités laser (> 1018 W/cm2), une cible solide est rapidement transformée en plasma. Une fraction de sa population électronique est accélérée à des vitesses relativistes et à l'origine de la génération d'ions à des énergies très élevées. Les faisceaux de particules ainsi produits affichent des caractéristiques particulièrement intéressantes pour différentes applications (diagnostics de plasmas denses, fusion inertielle, protonthérapie...). Cependant, malgré la montée en puissance des installations laser, pour nombre d'entre elles, les énergies atteintes restent aujourd'hui insuffisantes, suscitant un important effort de recherche visant à optimiser les processus d'accélération. En se plaçant dans un régime d'interaction de ultra-haut contraste, nous avons étudié l'influence de l'épaisseur de la cible sur l'accélération des ions et dégager l'intérêt de l'interaction avec des feuilles minces. Au-delà d'un accroissement de l'énergie et du nombre d'ions accélérés par réduction de l'épaisseur de la cible, nous avons mis en évidence les caractéristiques de chaque étape de l'interaction. De plus, en tirant parti de ces conditions optimales d'interaction, nous avons étudié l'influence d'un gradient ionique en face arrière de la cible sur l'accélération des ions, conditions dans lesquelles intervient un mécanisme fin de déferlement ionique.

Published
2008

21. Double plasma mirror for ultrahigh temporal contrast ultraintense laser pulses

Author

Lévy, Anna, primary, Ceccotti, Tiberio, additional, D'Oliveira, Pascal, additional, Réau, Fabrice, additional, Perdrix, Michel, additional, Quéré, Fabien, additional, Monot, Pascal, additional, Bougeard, Michel, additional, Lagadec, Hervé, additional, Martin, Philippe, additional, Geindre, Jean-Paul, additional, and Audebert, Patrick, additional

Published
2007
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23. Proton Acceleration With High-Intensity Laser Pulses in Ultrahigh Contrast Regime.

Author

Lévy, Anna, Ceccotti, Tiberio, Popescu, Horia, Réau, Fabrice, D'Oliveira, Pascal, Monot, Pascal, Martin, Philippe, Geindre, Jean-Paul, and Lefebvre, Erik

Subjects
*PROTON accelerators, *PARTICLE accelerators, *NUCLEAR physics instruments, *ULTRASHORT laser pulses, *LASER beams, *LASER plasmas, *PLASMA gases, *PROTONS
Abstract

We investigate the interaction of a high-intensity (~5.1018 W/cm²) and short (~65 fs) laser pulse with thin foils (from 0.08 to 105 µm) in a regime of ultrahigh contrast (> 1010). This paper shows that for thicknesses less than about 10 µm, proton acceleration from both sides of the target presents quite symmetric features. Proton bunches emitted from each side show similar maximum energies and spatial characteristics. Moreover, we show that for ultrahigh-contrast pulses, the efficient acceleration mechanism is related to the Brunel effect and not to the ponderomotive force. Simulations performed with a 2-D particle-in-cell code are in close agreement with all experimental data. [ABSTRACT FROM AUTHOR]

Published
2008
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24. Isolated Nanoparticles' Surfaces and Interfaces Probed by Soft X-ray Photoelectron Spectroscopy

Author

Patanen, M., Sublemontier, Olivier, Papagiannouli, I, Gaudin, J., Blanchet, V., Lévy, Anna, Bassani, D, Benkoula, S., Liu, X.-J, Nicolas, C., Robert, E., Reynaud, C., Barreda, F.-A, Kintz, H, Gaveau, M.-A, Le Garrec, Jean-Luc, Aureau, D, Etcheberry, A, Huttula, M, Mitchell, James, Miron, C, University of Oulu, Laboratoire Edifices Nanométriques (LEDNA), Nanosciences et Innovation pour les Matériaux, la Biomédecine et l'Energie (ex SIS2M) (NIMBE UMR 3685), Institut Rayonnement Matière de Saclay (IRAMIS), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Institut Rayonnement Matière de Saclay (IRAMIS), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Centre d'Etudes Lasers Intenses et Applications (CELIA), Université de Bordeaux (UB)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Centre National de la Recherche Scientifique (CNRS), Institut des Nanosciences de Paris (INSP), Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), Institut des Sciences Moléculaires (ISM), Université Montesquieu - Bordeaux 4-Université Sciences et Technologies - Bordeaux 1 (UB)-École Nationale Supérieure de Chimie et de Physique de Bordeaux (ENSCPB)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Synchrotron SOLEIL (SSOLEIL), Centre National de la Recherche Scientifique (CNRS), Beihang University (BUAA), Laboratoire Interactions, Dynamiques et Lasers (ex SPAM) (LIDyl), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), Institut de Physique de Rennes (IPR), Université de Rennes (UR)-Centre National de la Recherche Scientifique (CNRS), Institut Lavoisier de Versailles (ILV), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Horia Hulubei National Institute of Physics and Nuclear Engineering (NIPNE), IFIN-HH, Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Institut Rayonnement Matière de Saclay (IRAMIS), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC), Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Bordeaux (UB), Université Montesquieu - Bordeaux 4-Université Sciences et Technologies - Bordeaux 1-École Nationale Supérieure de Chimie et de Physique de Bordeaux (ENSCPB)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Université Paris-Saclay-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Centre National de la Recherche Scientifique (CNRS), Université de Rennes 1 (UR1), Université de Rennes (UNIV-RENNES)-Université de Rennes (UNIV-RENNES)-Centre National de la Recherche Scientifique (CNRS), and Centre National de la Recherche Scientifique (CNRS)-École Nationale Supérieure de Chimie et de Physique de Bordeaux (ENSCPB)-Université Sciences et Technologies - Bordeaux 1-Université Montesquieu - Bordeaux 4-Institut de Chimie du CNRS (INC)

Subjects
[CHIM.MATE]Chemical Sciences/Material chemistry, ComputingMilieux_MISCELLANEOUS
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