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1. Evidence for highly p-type doping and type II band alignment in large scale monolayer WSe2/Se-terminated GaAs heterojunction grown by molecular beam epitaxy

Author

Debora Pierucci, Aymen Mahmoudi, Mathieu Silly, Federico Bisti, Fabrice Oehler, Gilles Patriarche, Frédéric Bonell, Alain Marty, Céline Vergnaud, Matthieu Jamet, Hervé Boukari, Emmanuel Lhuillier, Marco Pala, Abdelkarim Ouerghi, Centre de Nanosciences et de Nanotechnologies (C2N), Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), Synchrotron SOLEIL (SSOLEIL), Centre National de la Recherche Scientifique (CNRS), Dipartimento di Scienze Fisiche e Chimiche [L'Aquila], Università degli Studi dell'Aquila = University of L'Aquila (UNIVAQ), SPINtronique et TEchnologie des Composants (SPINTEC), Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche Interdisciplinaire de Grenoble (IRIG), Direction de Recherche Fondamentale (CEA) (DRF (CEA)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Direction de Recherche Fondamentale (CEA) (DRF (CEA)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Grenoble Alpes (UGA), Nanophysique et Semiconducteurs (NEEL - NPSC), Institut Néel (NEEL), Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes (UGA)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP ), Université Grenoble Alpes (UGA)-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes (UGA)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP ), Université Grenoble Alpes (UGA), Institut des Nanosciences de Paris (INSP), Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), ANR-17-CE24-0030,RhomboG,Propriétés electroniques de couches minces de graphite rhombohedrique(2017), ANR-18-CE24-0007,MAGICVALLEY,Polarisation de vallée induite par couplage d'échange magnétique dans les matériaux 2D à grande échelle(2018), ANR-19-CE09-0026,GRaSkop,Tuning Giant Rashba Spin-Orbit Coupling in Polar Single Layer Transition Metal Dichalcogenides(2019), and ANR-10-LABX-0051,LANEF,Laboratory of Alliances on Nanosciences - Energy for the Future(2010)

Subjects
Condensed Matter - Materials Science, Condensed Matter - Mesoscale and Nanoscale Physics, Mesoscale and Nanoscale Physics (cond-mat.mes-hall), Materials Science (cond-mat.mtrl-sci), FOS: Physical sciences, General Materials Science, [PHYS.COND]Physics [physics]/Condensed Matter [cond-mat]
Abstract

International audience; Two-dimensional materials (2D) arranged in hybrid van der Waals (vdW) heterostructures provide a route toward the assembly of 2D and conventional III–V semiconductors. Here{,} we report the structural and electronic properties of single layer WSe2 grown by molecular beam epitaxy on Se-terminated GaAs(111)B. Reflection high-energy electron diffraction images exhibit sharp streaky features indicative of a high-quality WSe2 layer produced via vdW epitaxy. This is confirmed by in-plane X-ray diffraction. The single layer of WSe2 and the absence of interdiffusion at the interface are confirmed by high resolution X-ray photoemission spectroscopy and high-resolution transmission microscopy. Angle-resolved photoemission investigation revealed a well-defined WSe2 band dispersion and a high p-doping coming from the charge transfer between the WSe2 monolayer and the Se-terminated GaAs substrate. By comparing our results with local and hybrid functionals theoretical calculation{,} we find that the top of the valence band of the experimental heterostructure is close to the calculations for free standing single layer WSe2. Our experiments demonstrate that the proximity of the Se-terminated GaAs substrate can significantly tune the electronic properties of WSe2. The valence band maximum (VBM{,} located at the K point of the Brillouin zone) presents an upshift of about 0.56 eV toward the Fermi level with respect to the VBM of the WSe2 on graphene layer{,} which is indicative of high p-type doping and a key feature for applications in nanoelectronics and optoelectronics.

Published
2022
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2. Ab initio lifetime correction to scattering states for time-dependent electronic-structure calculations with incomplete basis sets

Author

Eleonora Luppi, Roland Assaraf, Emanuele Coccia, Julien Toulouse, Laboratoire de chimie théorique (LCT), Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Dipartimento di Scienze Fisiche e Chimiche [L'Aquila], Università degli Studi dell'Aquila (UNIVAQ), Coccia, E, Assaraf, R, Luppi, E, Toulouse, J, and Università degli Studi dell'Aquila = University of L'Aquila (UNIVAQ)

Subjects
Atomic Physics (physics.atom-ph), Ab initio, FOS: Physical sciences, General Physics and Astronomy, HIGH-HARMONIC GENERATION, Electronic structure, 01 natural sciences, Physics - Atomic Physics, Schrödinger equation, DENSITY-FUNCTIONAL THEORY, ATOMS, [PHYS.PHYS.PHYS-COMP-PH]Physics [physics]/Physics [physics]/Computational Physics [physics.comp-ph], symbols.namesake, GAUSSIAN-BASIS SETS, MULTIPHOTON IONIZATION, ATTOSECOND SCIENCE, QUANTUM-MECHANICS, LASER FIELDS, PHOTOEMISSION, SPECTROSCOPY, Ab initio quantum chemistry methods, Physics - Chemical Physics, Quantum mechanics, 0103 physical sciences, Physical and Theoretical Chemistry, 010306 general physics, Wave function, Basis set, Chemical Physics (physics.chem-ph), Physics, 010304 chemical physics, Basis (linear algebra), Scattering, Computational Physics (physics.comp-ph), [CHIM.THEO]Chemical Sciences/Theoretical and/or physical chemistry, symbols, [PHYS.PHYS.PHYS-CHEM-PH]Physics [physics]/Physics [physics]/Chemical Physics [physics.chem-ph], Physics - Computational Physics
Abstract

International audience; We propose a method for obtaining effective lifetimes of scattering electronic states for avoiding the artificially confinement of the wave function due to the use of incomplete basis sets in time-dependent electronic-structure calculations of atoms and molecules. In this method, using a fitting procedure, the lifetimes are extracted from the spatial asymptotic decay of the approximate scattering wave functions obtained with a given basis set. The method is based on a rigorous analysis of the complex-energy solutions of the Schrödinger equation. It gives lifetimes adapted to any given basis set without using any empirical parameters. The method can be considered as an ab initio version of the heuristic lifetime model of Klinkusch et al. [J. Chem. Phys. 131, 114304 (2009)]. The method is validated on the H and He atoms using Gaussian-type basis sets for calculation of high-harmonic-generation spectra.

Published
2017
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3. Ultraviolet Radiation evolution during the 21st century

Author

Lamy, Kévin, Josse, Béatrice, Portafaix, Thierry, Bencherif, Hassan, Godin-Beekmann, Sophie, Brogniez, Colette, Abraham, N. L., Akiyoshi, H., Archibald, A. T., Bekki, Slimane, Butchart, N., Chipperfield, Martyn P., Currie, R., Di Genova, Glauco, Garcia, R. R., Deushi, Makoto, Dhomse, Sandip, Duncan, B. N., Hegglin, M. I., Horowitz, L. W., Jöckel, P., Kinnison, D., Lamarque, J. F., Lin, M. Y., Mancini, E., Marchand, Marion, Marécal, Virginie, Michou, M., Morgenstern, Olaf, O'Connor, F. M., Nagashima, T., Oman, L. D., Pitari, G., Plummer, D., Pyle, J. A., Revell, Laura E., Rozanov, E., Saint-Martin, D., Scinocca, J. F., Stenke, A., Strahan, S. E., Stone, K., Sudo, K., Tanaka, T. Y., Tilmes, S., Yamashita, Y., Yoshida, K., Zeng, G., Laboratoire de l'Atmosphère et des Cyclones (LACy), Centre National de la Recherche Scientifique (CNRS)-Université de La Réunion (UR)-Institut national des sciences de l'Univers (INSU - CNRS)-Météo France, Centre national de recherches météorologiques (CNRM), Institut national des sciences de l'Univers (INSU - CNRS)-Météo France-Centre National de la Recherche Scientifique (CNRS), STRATO - LATMOS, Laboratoire Atmosphères, Milieux, Observations Spatiales (LATMOS), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Laboratoire d’Optique Atmosphérique - UMR 8518 (LOA), Institut national des sciences de l'Univers (INSU - CNRS)-Université de Lille-Centre National de la Recherche Scientifique (CNRS), Department of Chemistry [Cambridge, UK], University of Cambridge [UK] (CAM), National Institute for Environmental Studies (NIES), Met Office Hadley Centre for Climate Change (MOHC), United Kingdom Met Office [Exeter], School of Earth and Environment [Leeds] (SEE), University of Leeds, University of L'Aquila [Italy] (UNIVAQ), National Center for Atmospheric Research [Boulder] (NCAR), Meteorological Research Institute [Tsukuba] (MRI), Japan Meteorological Agency (JMA), NASA Goddard Space Flight Center (GSFC), Department of Meteorology [Reading], University of Reading (UOR), NOAA Geophysical Fluid Dynamics Laboratory (GFDL), National Oceanic and Atmospheric Administration (NOAA), DLR Institut für Physik der Atmosphäre (IPA), Deutsches Zentrum für Luft- und Raumfahrt [Oberpfaffenhofen-Wessling] (DLR), Dipartimento di Scienze Fisiche e Chimiche [L'Aquila], Università degli Studi dell'Aquila (UNIVAQ), National Institute of Water and Atmospheric Research [Lauder] (NIWA), Environment and Climate Change Canada, Institute for Atmospheric and Climate Science [Zürich] (IAC), Eidgenössische Technische Hochschule - Swiss Federal Institute of Technology [Zürich] (ETH Zürich), Bodeker Scientific, School of Earth Sciences [Melbourne], Faculty of Science [Melbourne], University of Melbourne-University of Melbourne, Graduate School of Environmental Studies [Nagoya], Nagoya University, National Institute of Water and Atmospheric Research [Auckland] (NIWA), Institut national des sciences de l'Univers (INSU - CNRS)-Météo France-Université de La Réunion (UR)-Centre National de la Recherche Scientifique (CNRS), Institut national des sciences de l'Univers (INSU - CNRS)-Université de La Réunion (UR)-Centre National de la Recherche Scientifique (CNRS)-Météo-France, Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Centre National de la Recherche Scientifique (CNRS), and Università degli Studi dell'Aquila = University of L'Aquila (UNIVAQ)

Subjects
[SDU.OCEAN]Sciences of the Universe [physics]/Ocean, Atmosphere
Abstract

International audience; In the context of a changing climate, the acceleration of the Brewer-Dobson circulation [Butchart 2014] leadsto a decrease of the ozone total column in the tropics. This decrease affects directly surface ultraviolet radiation,which are already very high in this area. Following the work of (Bais et al., 2011), (Butchart, 2014)and (Hegglin & Shepherd, 2009) on the future evolution of surface irradiance derived from Chemistry ClimateModels (CCM) projections, we projected here surface irradiance from 2010 to 2100 with focus on the tropics.We used the latest chemistry climate projection exercise ; Chemistry Climate Model Initiative (CCMI) coupledwith a radiative transfer model (TUV (Madronich, 1993)) to calculate the evolution of surface Ultravioletradiation throughout the 21st century. Ultraviolet Index (UVi) has been specifically considered (McKenzie,Matthews, & Johnston, 1991).At first, simulation from RefC2 Chemistry Climate Model Initiative have been coupled with a radiativetransfer model, in order to obtained modeled UV index (UVi-M). UVi-M is then compared against availablesatellite ultraviolet radiation observations (OMI OMUVbd product) between 2005 and 2016. Statistical differenceand variance have been analysed versus different parameters: geographical location, model or ensembleof model outputs used in the radiative transfer calculation.

Published
2017

4. Time-Dependent Linear-Response Variational Monte Carlo

Author

Mussard, Bastien, Coccia, Emanuele, Assaraf, Roland, Otten, Matt, Umrigar, C. J., Toulouse, Julien, Mussard, B, Coccia, E, Assaraf, R, Otten, M, Umrigar, C J, Toulouse, J., Laboratoire de chimie théorique (LCT), Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Institut des Sciences du Calcul et des Données (ISCD), Université Pierre et Marie Curie - Paris 6 (UPMC)-Sorbonne Université (SU), Dipartimento di Scienze Fisiche e Chimiche [L'Aquila], Università degli Studi dell'Aquila (UNIVAQ), Laboratory of Atomic and Solid State Physics [Ithaca] (LASSP), Cornell University [New York], Université Pierre et Marie Curie - Paris 6 (UPMC), and Università degli Studi dell'Aquila = University of L'Aquila (UNIVAQ)

Subjects
Chemical Physics (physics.chem-ph), Physics::Computational Physics, Tamm-Dancoff approximation, GEMINAL POWER, WAVE-FUNCTIONS, EXCITATION, MOLECULES, oscillator strengths, FOS: Physical sciences, excitation energies, Computational Physics (physics.comp-ph), beryllium, [CHIM.THEO]Chemical Sciences/Theoretical and/or physical chemistry, [PHYS.PHYS.PHYS-COMP-PH]Physics [physics]/Physics [physics]/Computational Physics [physics.comp-ph], linear method, Physics - Chemical Physics, [PHYS.PHYS.PHYS-CHEM-PH]Physics [physics]/Physics [physics]/Chemical Physics [physics.chem-ph], Physics - Computational Physics
Abstract

We present the extension of variational Monte Carlo (VMC) to the calculation of electronic excitation energies and oscillator strengths using time-dependent linear-response theory. By exploiting the analogy existing between the linear method for wave-function optimisation and the generalised eigenvalue equation of linear-response theory, we formulate the equations of linear-response VMC (LR-VMC). This LR-VMC approach involves the first-and second-order derivatives of the wave function with respect to the parameters. We perform first tests of the LR-VMC method within the Tamm-Dancoff approximation using single-determinant Jastrow-Slater wave functions with different Slater basis sets on some singlet and triplet excitations of the beryllium atom. Comparison with reference experimental data and with configuration-interaction-singles (CIS) results shows that LR-VMC generally outperforms CIS for excitation energies and is thus a promising approach for calculating electronic excited-state properties of atoms and molecules., Advances in Quantum Chemistry, 2017, Novel Electronic Structure Theory: General Innovations and Strongly Correlated Systems

Published
2017

5. Massive and modified gravity as self-gravitating media

Author

Ballesteros, Guillermo, Comelli, Denis, Pilo, Luigi, Institut de Physique Théorique - UMR CNRS 3681 (IPHT), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), Theory Division, CERN [Genève], Istituto Nazionale di Fisica Nucleare [Ferrara] (INFN), Istituto Nazionale di Fisica Nucleare (INFN), Dipartimento di Scienze Fisiche e Chimiche [L'Aquila], Università degli Studi dell'Aquila = University of L'Aquila (UNIVAQ), and European Project: 656794,H2020,H2020-MSCA-IF-2014,DEFT(2015)

Subjects
High Energy Physics - Theory, Gravity (chemistry), Cosmology and Nongalactic Astrophysics (astro-ph.CO), Field (physics), FOS: Physical sciences, General Relativity and Quantum Cosmology (gr-qc), 01 natural sciences, General Relativity and Quantum Cosmology, Superfluidity, [PHYS.ASTR.CO]Physics [physics]/Astrophysics [astro-ph]/Cosmology and Extra-Galactic Astrophysics [astro-ph.CO], High Energy Physics - Phenomenology (hep-ph), 0103 physical sciences, Effective field theory, 010306 general physics, Physics, 010308 nuclear & particles physics, [PHYS.HTHE]Physics [physics]/High Energy Physics - Theory [hep-th], Scalar (physics), Symmetry (physics), High Energy Physics - Phenomenology, Classical mechanics, Massive gravity, High Energy Physics - Theory (hep-th), [PHYS.HPHE]Physics [physics]/High Energy Physics - Phenomenology [hep-ph], Dark energy, [PHYS.GRQC]Physics [physics]/General Relativity and Quantum Cosmology [gr-qc], Particle Physics - Theory, Astrophysics - Cosmology and Nongalactic Astrophysics
Abstract

We study the effective field theory that describes the low-energy physics of self-gravitating media. The field content consists of four derivatively coupled scalar fields that can be identified with the internal comoving coordinates of the medium. Imposing SO(3) internal spatial invariance, the theory describes supersolids. Stronger symmetry requirements lead to superfluids, solids and perfect fluids, at lowest order in derivatives. In the unitary gauge, massive gravity emerges, being thus the result of a continuous medium propagating in spacetime. Our results can be used to explore systematically the effects and signatures of modifying gravity consistently at large distances. The dark sector is then described as a self-gravitating medium with dynamical and thermodynamic properties dictated by internal symmetries. These results indicate that the divide between dark energy and modified gravity, at large distance scales, is simply a gauge choice., Comment: 41 pages, new section, to appear in Phys. Rev. D

Published
2016
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6. Assimilation of lidar signals: application to aerosol forecasting in the western Mediterranean basin

Author

Francisco Molero, Gelsomina Pappalardo, A. Papayannis, Lucas Alados-Arboledas, Karine Sartelet, Marco Iarlori, J. Preissler, Aldo Amodeo, Jordi Bach, Karine Sellegri, David Garcia-Vizcaino, X. Bush, Frank Wagner, Yiguo Wang, Ioannis Binietoglou, Francesc Rocadenbosch, Livio Belegante, Nadège Montoux, Doina Nicolae, Alvaro Muñoz, Constantino Munoz, Michaël Sicard, Jean-François Léon, Hervé Delbarre, Patrick Chazette, Juan Luis Guerrero-Rascado, François Dulac, Panagiotis Kokkalis, Vincenzo Rizi, Maxime Hervo, Adolfo Comerón, Marc Bocquet, Giuseppe D'Amico, Diego Lange, Patrick Augustin, Universitat Politècnica de Catalunya. Departament de Teoria del Senyal i Comunicacions, Universitat Politècnica de Catalunya. RSLAB - Grup de Recerca en Teledetecció, Centre d'Enseignement et de Recherche en Environnement Atmosphérique (CEREA), École des Ponts ParisTech (ENPC)-EDF R&D (EDF R&D), EDF (EDF)-EDF (EDF), Laboratoire des Sciences du Climat et de l'Environnement [Gif-sur-Yvette] (LSCE), Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ), Coupling environmental data and simulation models for software integration (Clime), Inria Paris-Rocquencourt, Institut National de Recherche en Informatique et en Automatique (Inria)-Institut National de Recherche en Informatique et en Automatique (Inria), Chimie Atmosphérique Expérimentale (CAE), Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ), Remote Sensing Laboratory [Barcelona] (RSLab), Universitat Politècnica de Catalunya [Barcelona] (UPC), Centre de Recerca de l'Aeronàutica i de l'Espai, Istituto di Metodologie per l'Analisi Ambientale (IMAA), Consiglio Nazionale delle Ricerche [Potenza] (CNR), Laboratoire d'aérologie (LAERO), Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Observatoire Midi-Pyrénées (OMP), Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS), IISTA, University of Granada, University of Granada [Granada]-University of Granada [Granada], Department Applied Physics [Granada], University of Granada [Granada], Laboratoire de Physico-Chimie de l'Atmosphère (LPCA), Université du Littoral Côte d'Opale (ULCO)-Centre National de la Recherche Scientifique (CNRS), National Institute of Research and Development for Optoelectronics (INOE), Laboratoire de météorologie physique (LaMP), Centre National de la Recherche Scientifique (CNRS)-Université Blaise Pascal - Clermont-Ferrand 2 (UBP)-Institut national des sciences de l'Univers (INSU - CNRS), CETEMPS, Dipartimento di Scienze Fisiche e Chimiche [L'Aquila], Università degli Studi dell'Aquila (UNIVAQ)-Università degli Studi dell'Aquila (UNIVAQ), Laser Remote Sensing Laboratory, National Technical University of Athens [Athens] (NTUA), Department of Environment [CIEMAT Madrid], Centro de Investigaciones Energéticas Medioambientales y Tecnológicas [Madrid] (CIEMAT), University of Evora Departement of Geosciences and Geophysics Center of Evora, Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), Université de Toulouse (UT)-Université de Toulouse (UT)-Observatoire Midi-Pyrénées (OMP), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Centre National de la Recherche Scientifique (CNRS), Universidad de Granada = University of Granada (UGR), Université Blaise Pascal - Clermont-Ferrand 2 (UBP)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Università degli Studi dell'Aquila = University of L'Aquila (UNIVAQ)-Università degli Studi dell'Aquila = University of L'Aquila (UNIVAQ), Centre National de la Recherche Scientifique (CNRS)-Observatoire Midi-Pyrénées (OMP), Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), and Université Fédérale Toulouse Midi-Pyrénées

Subjects
Atmospheric Science, Teledetecció, Meteorology, Lidar assimilation, ERROR STATISTICS, Enginyeria de la telecomunicació::Radiocomunicació i exploració electromagnètica [Àrees temàtiques de la UPC], lcsh:Chemistry, Air quality model, VARIATIONAL DATA ASSIMILATION, Data assimilation, Altitude, AIR-QUALITY MODELS, ENSEMBLE KALMAN FILTER, VERTICAL STRUCTURE, Lidar signals, OPTIMAL INTERPOLATION, Aerosol, Air quality index, Làsers, Optical properties, biology, Lasers, TECHNICAL NOTE, Mediterranean basin, OPTICAL-PROPERTIES, Remote sensing, biology.organism_classification, [INFO.INFO-MO]Computer Science [cs]/Modeling and Simulation, lcsh:QC1-999, Trace gas, AERONET, Lidar, lcsh:QD1-999, Enginyeria de la telecomunicació::Radiocomunicació i exploració electromagnètica::Teledetecció [Àrees temàtiques de la UPC], 13. Climate action, Polyphemus, ChArMEx, TRANSPORT MODEL, THEORETICAL ASPECTS, lcsh:Physics
Abstract

This paper presents a new application of assimilating lidar signals to aerosol forecasting. It aims at investigating the impact of a ground-based lidar network on the analysis and short-term forecasts of aerosols through a case study in the Mediterranean basin. To do so, we employ a data assimilation (DA) algorithm based on the optimal interpolation method developed in the Polair3D chemistry transport model (CTM) of the Polyphemus air quality modelling platform. We assimilate hourly averaged normalised range-corrected lidar signals (PR2) retrieved from a 72 h period of intensive and continuous measurements performed in July 2012 by ground-based lidar systems of the European Aerosol Research Lidar Network (EARLINET) integrated into the Aerosols, Clouds, and Trace gases Research InfraStructure (ACTRIS) network and an additional system in Corsica deployed in the framework of the pre-ChArMEx (Chemistry-Aerosol Mediterranean Experiment)/TRAQA (TRAnsport à longue distance et Qualité de l'Air) campaign. This lidar campaign was dedicated to demonstrating the potential operationality of a research network like EARLINET and the potential usefulness of assimilation of lidar signals to aerosol forecasts. Particles with an aerodynamic diameter lower than 2.5 μm (PM2.5) and those with an aerodynamic diameter higher than 2.5 μm but lower than 10 μm (PM10–2.5) are analysed separately using the lidar observations at each DA step. First, we study the spatial and temporal influences of the assimilation of lidar signals on aerosol forecasting. We conduct sensitivity studies on algorithmic parameters, e.g. the horizontal correlation length (Lh) used in the background error covariance matrix (50 km, 100 km or 200 km), the altitudes at which DA is performed (0.75–3.5 km, 1.0–3.5 km or 1.5–3.5 km a.g.l.) and the assimilation period length (12 h or 24 h). We find that DA with Lh = 100 km and assimilation from 1.0 to 3.5 km a.g.l. during a 12 h assimilation period length leads to the best scores for PM10 and PM2.5 during the forecast period with reference to available measurements from surface networks. Secondly, the aerosol simulation results without and with lidar DA using the optimal parameters (Lh = 100 km, an assimilation altitude range from 1.0 to 3.5 km a.g.l. and a 12 h DA period) are evaluated using the level 2.0 (cloud-screened and quality-assured) aerosol optical depth (AOD) data from AERONET, and mass concentration measurements (PM10 or PM2.5) from the French air quality (BDQA) network and the EMEP-Spain/Portugal network. The results show that the simulation with DA leads to better scores than the one without DA for PM2.5, PM10and AOD. Additionally, the comparison of model results to evaluation data indicates that the temporal impact of assimilating lidar signals is longer than 36 h after the assimilation period., This work was supported by CEA (Commissariat à l’Énergie Atomique) and CEREA joint laboratory École des Ponts ParisTech – EDF R&D. We thank all participants of the EARLINET network and MISTRALS/ChArMEx (Chemistry-Aerosol Mediterranean Experiment, http://charmex.lsce.ipsl.fr/) for the 72 h continuous measurements. Forecasts and near-real-time quick looks for the lidar measurement alert have been provided by the MISTRALS/ChArMEx Operating Center (http://choc.sedoo.fr/) set-up at OMP (L’Observatoire Midi-Pyrénées), Toulouse. Lidar measurements are supported by the 7th Framework Programme project Aerosols, Clouds, and Trace Gases Research InfraStructure (ACTRIS) network (grant agreement no. 262254). The Barcelona EARLINET lidar team thanks the Spanish Ministry of Economy and Competitivity and European Regional Development (FEDER) funds through project TEC2012-34575 and Scientific and Technological Infrastructure project UNPC10-4E-442, as well as the Spanish Ministry of Science and Innovation and FEDER funds under projects CGL2011-13580-E/CLI and CGL2011-16124-E/CLI.

Published
2014
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7. Fermi resonance as a tool for probing peridinin environment

Author

Marie Basire, Elizabeth Kish, Leonardo Guidoni, Riccardo Spezia, Maria Manuela Mendes Pinto, Rodolphe Vuilleumier, Alberto Mezzetti, Bruno Robert, Daniele Bovi, Institut de Biologie et de Technologies de Saclay (IBITECS), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay, Dipartimento di Fisica [Roma La Sapienza], Università degli Studi di Roma 'La Sapienza' = Sapienza University [Rome] (UNIROMA), Processus d'Activation Sélective par Transfert d'Energie Uni-électronique ou Radiatif (UMR 8640) (PASTEUR), Université Pierre et Marie Curie - Paris 6 (UPMC)-Département de Chimie - ENS Paris, École normale supérieure - Paris (ENS-PSL), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-École normale supérieure - Paris (ENS-PSL), 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), Département de Chimie - ENS Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL), Dipartimento di Scienze Fisiche e Chimiche [L'Aquila], Università degli Studi dell'Aquila = University of L'Aquila (UNIVAQ), Laboratoire Analyse et Modélisation pour la Biologie et l'Environnement (LAMBE), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Cergy Pontoise (UCP), Université Paris-Seine-Université Paris-Seine-Université d'Évry-Val-d'Essonne (UEVE)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Laboratoire Avancé de Spectroscopie pour les Intéractions la Réactivité et l'Environnement - UMR 8516 (LASIRE), Institut de Chimie du CNRS (INC)-Université de Lille-Centre National de la Recherche Scientifique (CNRS), Université Paris-Saclay-Commissariat à l'énergie atomique et aux énergies alternatives (CEA), Università degli Studi di Roma 'La Sapienza' = Sapienza University [Rome], École normale supérieure - Paris (ENS Paris), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-École normale supérieure - Paris (ENS Paris), Università degli Studi dell'Aquila (UNIVAQ), Université Paris-Seine-Université Paris-Seine-Université d'Évry-Val-d'Essonne (UEVE)-Centre National de la Recherche Scientifique (CNRS), Centre National de la Recherche Scientifique (CNRS)-Centrale Lille Institut (CLIL)-Institut de Chimie du CNRS (INC)-Université de Lille, and Institut de Chimie du CNRS (INC)-Université de Lille-Centre National de la Recherche Scientifique (CNRS)-Centrale Lille Institut (CLIL)

Subjects
Resonance structures, Polarity (physics), Overtone, Resonance Raman spectroscopy, Photochemistry, Spectrum Analysis, Raman, Molecular physics, Spectral line, chemistry.chemical_compound, Carbonyls, Materials Chemistry, Physical and Theoretical Chemistry, Quantitative Biology::Biomolecules, Polarity, Resonance (chemistry), Polyene, Carotenoids, Hydrocarbons, Surfaces, Coatings and Films, [CHIM.THEO]Chemical Sciences/Theoretical and/or physical chemistry, Peridinin, chemistry, Dinoflagellida, Solvents, Quantum Theory, Fermi resonance
Abstract

In the present paper, we provide an extended study of the vibrational signature of a butenolide carotenoid, peridinin, in various solvents by combining resonance Raman spectroscopy (RRS) with theoretical calculations. The presence of a Fermi resonance due to coupling between the lactonic C-O stretching and the overtone of the wagging of the C-H in the lactonic ring provides a spectroscopic way of differentiating between peridinins lying in different environments. This is a significant achievement, given that simultaneous presence of several peridinins (each with a peculiar photophysical role) in different environments occurs in the most important peridinin containing proteins, the peridinin-chlorophyll proteins (PCPs) and the Chl a-c2-peridinin binding proteins. In RRS, small modifications of solvent polarity can give rise to large differences in the intensity and splitting between the two bands, resulting from the Fermi resonance. By changing the polarity, we can tune the frequency of stretching of the C-O and, while the C-H wagging frequency is almost always constant in different solvents, move the system from a perfect resonance condition to off-resonance ones. We have corroborated our spectroscopic findings with a quasi-classical dynamical model of two coupled oscillators, and DFT calculations on peridinin in different solvents; we have also used calculations to complete the peridinin vibrational mode assignments in the 800-1600 cm-1 region of RRS spectra, corresponding to polyene chain motion. Finally, the presence of Fermi resonance has been used to reinterpret previous vibrational spectroscopic experiments in PCPs.

Published
2014
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8. Validation of MIPAS-ENVISAT H2O operational data collected between July 2002 and March 2004

Author

Wetzel, G., Oelhaf, Hermann, Berthet, Gwenaël, Bracher, A., Cornacchia, C, Feist, D. G., Fischer, H, Fix, A., Iarlori, M., Kleinert, A., Lengel, A., Milz, M., Mona, L., Müller, S.C., Ovarlez, J., Pappalarda, G., Piccolo, C., Raspollini, P., Renard, Jean-Baptiste, Rizi, V., Rohs, S., Schiller, C., Weber, M., Zhang, G., Institute for Meteorology and Climate Research (IMK), Karlsruhe Institute of Technology (KIT), Laboratoire de Physique et Chimie de l'Environnement et de l'Espace (LPC2E), Observatoire des Sciences de l'Univers en région Centre (OSUC), Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université d'Orléans (UO)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université d'Orléans (UO)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National d’Études Spatiales [Paris] (CNES), Institute of Environmental Physics and Remote Sensing [Bremen] (IUP/IFE), University of Bremen, Istituto di Metodologie per l'Analisi Ambientale (IMAA), Consiglio Nazionale delle Ricerche [Potenza] (CNR), Max Planck Society, Department of Higher Mathematics and Mathematical Physics, Tomsk Polytechnic University [Russie] (UPT), CETEMPS, Dipartimento di Scienze Fisiche e Chimiche [L'Aquila], Università degli Studi dell'Aquila (UNIVAQ)-Università degli Studi dell'Aquila (UNIVAQ), Department of Computer Science [Kiruna], Luleå University of Technology (LUT), Institute of Applied Physics [Bern] (IAP), University of Bern, Istituto di Fisica Applicata 'Nello Carrara' (IFAC), Consiglio Nazionale delle Ricerche [Roma] (CNR), Institute for Energy and Climate Research – Stratosphere, Institute for Energy and Climate Research (IEK), Forschungszentrum Jülich GmbH | Centre de recherche de Juliers, Helmholtz-Gemeinschaft = Helmholtz Association-Helmholtz-Gemeinschaft = Helmholtz Association, DLR (Project 50EE0020), ANR-10-LABX-0100,VOLTAIRE,Geofluids and Volatil elements – Earth, Atmosphere, Interfaces – Resources and Environment(2010), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, and Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Centre National d’Études Spatiales [Paris] (CNES)

Subjects
[SDU]Sciences of the Universe [physics]
Abstract

International audience; Water vapour (H2O) is one of the operationallyretrieved key species of the Michelson Interferometer forPassive Atmospheric Sounding (MIPAS) instrument aboardthe Environmental Satellite (ENVISAT) which was launchedinto its sun-synchronous orbit on 1 March 2002 and operateduntil April 2012. Within the MIPAS validation activities,independent observations from balloons, aircraft, satellites,and ground-based stations have been compared to EuropeanSpace Agency (ESA) version 4.61 operational H2Odata comprising the time period from July 2002 until March2004 where MIPAS measured with full spectral resolution.No significant bias in the MIPAS H2O data is seen in thelower stratosphere (above the hygropause) between about15 and 30 km. Differences of H2O quantities observed byMIPAS and the validation instruments are mostly well withinthe combined total errors in this altitude region. In the upperstratosphere (above about 30 km), a tendency towardsa small positive bias (up to about 10 %) is present in theMIPAS data when compared to its balloon-borne counterpartMIPAS-B, to the satellite instruments HALOE (HalogenOccultation Experiment) and ACE-FTS (AtmosphericChemistry Experiment, Fourier Transform Spectrometer),and to the millimeter-wave airborne sensor AMSOS (AirborneMicrowave Stratospheric Observing System). In themesosphere the situation is unclear due to the occurrenceof different biases when comparing HALOE and ACE-FTSdata. Pronounced deviations between MIPAS and the correlativeinstruments occur in the lowermost stratosphere and upper troposphere, a region where retrievals of H2O are mostchallenging. Altogether it can be concluded that MIPAS H2Oprofiles yield valuable information on the vertical distributionof H2O in the stratosphere with an overall accuracy ofabout 10 to 30% and a precision of typically 5 to 15% –well within the predicted error budget, showing that theseglobal and continuous data are very valuable for scientificstudies. However, in the region around the tropopause retrievedMIPAS H2O profiles are less reliable, suffering froma number of obstacles such as retrieval boundary and cloudeffects, sharp vertical discontinuities, and frequent horizontalgradients in both temperature and H2O volume mixing ratio(VMR). Some profiles are characterized by retrieval instabilities.

Published
2013
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9. Hydration Properties and Ionic Radii of Actinide(III) Ions in Aqueous Solution

Author

Riccardo Spezia, Fausto Martelli, Adriano Filipponi, Paola D'Angelo, Melissa A. Denecke, Dipartimento di Chimica, Università degli Studi di Roma 'La Sapienza' = Sapienza University [Rome], Laboratoire Analyse et Modélisation pour la Biologie et l'Environnement (LAMBE), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Cergy Pontoise (UCP), Université Paris-Seine-Université Paris-Seine-Université d'Évry-Val-d'Essonne (UEVE)-Centre National de la Recherche Scientifique (CNRS), Dipartimento di Scienze Fisiche e Chimiche [L'Aquila], Università degli Studi dell'Aquila (UNIVAQ), Institut für Nukleare Entsorgung (INE), Karlsruher Institut für Technologie (KIT), Università degli Studi di Roma 'La Sapienza' = Sapienza University [Rome] (UNIROMA), Université Paris-Seine-Université Paris-Seine-Université d'Évry-Val-d'Essonne (UEVE)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), and Università degli Studi dell'Aquila = University of L'Aquila (UNIVAQ)

Subjects
Lanthanide, Aqueous solution, Ionic radius, Extended X-ray absorption fine structure, 010405 organic chemistry, Chemistry, Inorganic chemistry, Actinide, 010402 general chemistry, 01 natural sciences, 0104 chemical sciences, Ion, Inorganic Chemistry, Molecular dynamics, Physical chemistry, [PHYS.PHYS.PHYS-CHEM-PH]Physics [physics]/Physics [physics]/Chemical Physics [physics.chem-ph], Physical and Theoretical Chemistry, Absorption (chemistry)
Abstract

International audience; Ionic radii of actinide(III) cations (from U(III) to Cf(III)) in aqueous solution have been derived for the first time starting from accurate experimental determination of the ion–water distances obtained by combining extended X-ray absorption fine structure (EXAFS) results and molecular dynamics (MD) structural data. A strong analogy has been found between the lanthanide and actinide series concerning hydration properties. The existence of a contraction of the An–O distance along the series has been highlighted, while no decrease of the hydration number is evident up to Cf(III).

Published
2013
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10. X-ray magnetic circular dichroism measured at the FeK-edge with a reduced intrinsic broadening: x-ray absorption spectroscopy versus resonant inelastic x-ray scattering measurements

Author

Fabrice Wilhelm, Andrei Rogalev, Philippe Sainctavit, Katharina Ollefs, Adriano Filipponi, Pieter Glatzel, Amélie Juhin, Marcin Sikora, Institut de minéralogie, de physique des matériaux et de cosmochimie (IMPMC), Muséum national d'Histoire naturelle (MNHN)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut de recherche pour le développement [IRD] : UR206-Centre National de la Recherche Scientifique (CNRS), European Synchrotron Radiation Facility (ESRF), Center for Nanointegration Duisburg-Essen (CeNIDE), Universität Duisburg-Essen [Essen], Academic Centre for Materials and Nanotechnology, AGH University of Science and Technology [Krakow, PL] (AGH UST), Dipartimento di Scienze Fisiche e Chimiche [L'Aquila], Università degli Studi dell'Aquila (UNIVAQ), Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut de recherche pour le développement [IRD] : UR206-Muséum national d'Histoire naturelle (MNHN)-Centre National de la Recherche Scientifique (CNRS), Universität Duisburg-Essen = University of Duisburg-Essen [Essen], and Università degli Studi dell'Aquila = University of L'Aquila (UNIVAQ)

Subjects
Absorption spectroscopy, Yttrium iron garnet, 02 engineering and technology, 01 natural sciences, chemistry.chemical_compound, RIXS-MCD, 0103 physical sciences, General Materials Science, [PHYS.PHYS.PHYS-INS-DET]Physics [physics]/Physics [physics]/Instrumentation and Detectors [physics.ins-det], corehole lifetime, [PHYS.COND]Physics [physics]/Condensed Matter [cond-mat], 010306 general physics, Spectroscopy, XMCD, Magnetic circular dichroism, Chemistry, Scattering, Physik (inkl. Astronomie), 021001 nanoscience & nanotechnology, Condensed Matter Physics, broadening, Materials Science (all), Resonant inelastic X-ray scattering, K-edge, X-ray magnetic circular dichroism, Atomic physics, 0210 nano-technology
Abstract

International audience; X-ray Magnetic Circular Dichroism is measured at the Fe K pre-edge in Yttrium Iron Garnet using two different procedures that allow reducing the intrinsic broadening due to the 1s corehole lifetime. First, deconvolution of XMCD data measured in Total Fluorescence Yield (TFY) with an extremely high signal-to-noise ratio enables to gain a factor of 2.4 in the XMCD intensity. Ligand Field Multiplet calculations performed with different values of intrinsic broadening show that deconvolving such high quality XMCD data is similar to reducing the lifetime broadening from a 1s corehole to a 2p corehole. Second, MCD is measured by Resonant Inelastic X-ray Scattering spectroscopy as a function of incident energy and emission energy. Selection of a fixed emission energy, instead of using the TFY, allows enhancing the MCD intensity up to a factor of ∼4.7. However, this significantly changes the spectral shape of the XMCD signal, which cannot be interpreted any more as an absorption spectrum.

Published
2016
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11. Probing phase transitions under extreme conditions by ultrafast techniques: Advances at the Fermi@Elettra free-electron-laser facility

Author

Emiliano Principi, Cristian Svetina, Claudio Masciovecchio, Fulvio Parmigiani, Goran Zgrablić, Francesco D'Amico, Roberto Gunnella, Adriano Filipponi, Filippo Bencivenga, Andrea Di Cicco, CNISM, Department of Physics, University of Camerino, CNISM, Synchrotron ELETTRA, Institut de minéralogie et de physique des milieux condensés (IMPMC), Université Pierre et Marie Curie - Paris 6 (UPMC)-IPG PARIS-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), Dipartimento di Scienze Fisiche e Chimiche [L'Aquila], Università degli Studi dell'Aquila (UNIVAQ), Université Pierre et Marie Curie - Paris 6 (UPMC)-Université Paris Diderot - Paris 7 (UPD7)-Institut de Physique du Globe de Paris (IPG Paris)-Centre National de la Recherche Scientifique (CNRS), Università degli Studi dell'Aquila = University of L'Aquila (UNIVAQ), Di Cicco, A., D'Amico, F., Zgrablic, G., and Parmigiani, Fulvio

Subjects
Phase transition, Materials science, Photon, extreme conditions, Physics::Optics, 02 engineering and technology, 01 natural sciences, Ultra-fast phenomena, Metastability, 0103 physical sciences, Materials Chemistry, 010306 general physics, Laser high-temperature, Liquids femto-second experiments, Warm dense matter, Free-electron laser, Free electron, 021001 nanoscience & nanotechnology, Condensed Matter Physics, Electronic, Optical and Magnetic Materials, Supercontinuum, [PHYS.COND.CM-GEN]Physics [physics]/Condensed Matter [cond-mat]/Other [cond-mat.other], Ceramics and Composites, Atomic physics, 0210 nano-technology, Ultrashort pulse, Fermi Gamma-ray Space Telescope
Abstract

International audience; Novel possibilities for studying matter under extreme conditions are opened by the forthcoming availability of free electron laser (FEL) facilities generating subpicosecond photon pulses of high intensity in the VUV and X-ray range, which are able to heat thin samples up to the warm dense matter (WDM) regime. Pump-andprobe ultrafast techniques can be used to study the dynamics of phase transitions and characterize the states under extreme and metastable conditions. Ultrafast (10-100 fs) bulk heating is seen as a novel route for accessing extremely high temperature regimes as well as the transition region between low-density and high density fluids, that is presently considered a no man's land in simple liquids and glasses. Here we briefly describe the present status of the TIMEX end-station devoted to those experimental activities at the Fermi@Elettra FEL facility, and some preliminary results obtained in a pilot ultrafast experiment using a laser source as a pump and a supercontinuum probe aimed to characterize the melting process of Silicon.

Published
2011
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12. Polyamorphic transition of germanium under pressure

Author

Frédéric Decremps, Simone De Panfilis, Alain Polian, Andriano Filipponi, Andrea Di Cicco, Emiliano Principi, Elettra Sincrotrone Trieste, CNISM, CNR-INFM SOFT, Dipartimento di Fisica, Universit`a degli Studi di Camerino, Via Madonna delle Carceri, CNISM, CNR-INFM SOFT, Institut de minéralogie et de physique des milieux condensés (IMPMC), Université Pierre et Marie Curie - Paris 6 (UPMC)-Université Paris Diderot - Paris 7 (UPD7)-Institut de Physique du Globe de Paris (IPG Paris)-Centre National de la Recherche Scientifique (CNRS), Institut de minéralogie, de physique des matériaux et de cosmochimie (IMPMC), Muséum national d'Histoire naturelle (MNHN)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut de recherche pour le développement [IRD] : UR206-Centre National de la Recherche Scientifique (CNRS), European Synchrotron Radiation Facility (ESRF), Dipartimento di Scienze Fisiche e Chimiche [L'Aquila], Università degli Studi dell'Aquila = University of L'Aquila (UNIVAQ), Université Pierre et Marie Curie - Paris 6 (UPMC)-IPG PARIS-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut de recherche pour le développement [IRD] : UR206-Muséum national d'Histoire naturelle (MNHN)-Centre National de la Recherche Scientifique (CNRS), and Università degli Studi dell'Aquila (UNIVAQ)

Subjects
Diffraction, [PHYS]Physics [physics], X-ray absorption spectroscopy, Materials science, Absorption spectroscopy, Fermi level, chemistry.chemical_element, Germanium, 02 engineering and technology, Electron, Electronic structure, 021001 nanoscience & nanotechnology, Condensed Matter Physics, 01 natural sciences, Electronic, Optical and Magnetic Materials, Condensed Matter::Materials Science, symbols.namesake, chemistry, Polyamorphism, 0103 physical sciences, symbols, Atomic physics, [PHYS.COND]Physics [physics]/Condensed Matter [cond-mat], 010306 general physics, 0210 nano-technology
Abstract

Pressure-induced transformations in the atomic and electronic structure of amorphous germanium $(a\ensuremath{-}\mathrm{Ge})$ have been investigated by using x-ray absorption spectroscopy (XAS) combined with energy-scanning x-ray diffraction. Our data show that an abrupt change in the local structure and in the electron states near the Fermi level occurs in evaporated $a\ensuremath{-}\mathrm{Ge}$ at a pressure of about 8 GPa. The transformation is clearly detectable by a change in the shape and energy shift in the near-edge structures and by an increase of the average first-neighbor distance measured by XAS. The occurrence of this polyamorphic transition is discussed in light of the recent advances in the study of multiple dense fluid phases.

Published
2004
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13. Aerosol lidar intercomparison in the framework of the EARLINET project 2 Aerosol backscatter algorithms

Author

C. BOKMANN, U. WANDINGER, A. ANSMANN, V. FREUDENTALER, J. BOSENBERG, V. AMIRIDIS, A. BOSELLI, A. DELAVAL, M. FRIOUD, I. V. GRIGOROV, A. HAGARD, M. HORVAT, M. IARLORI, L. KOMGUEN, S. KREIPL, G. LARCHEVEQUE, V. MATTHIAS, A. PAPAYANNIS, G. PAPPALARDO, F. ROCADENBOSCH, J. A. RODRIGUES, J. SCHNEIDER, V. SHCHERBACOV, M. WIEGNER, DE TOMASI, Ferdinando, Institut für Mathematik [Potsdam], University of Potsdam = Universität Potsdam, Leibniz Institute for Tropospheric Research (TROPOS), Max-Planck-Institut für Meteorologie (MPI-M), Max-Planck-Gesellschaft, Istituto di Metodologie per l'Analisi Ambientale (IMAA), Consiglio Nazionale delle Ricerche [Potenza] (CNR), CETEMPS, Dipartimento di Scienze Fisiche e Chimiche [L'Aquila], Università degli Studi dell'Aquila = University of L'Aquila (UNIVAQ)-Università degli Studi dell'Aquila = University of L'Aquila (UNIVAQ), Department of Physics [Aberystwyth], Aberystwyth University, Laser Remote Sensing Laboratory, National Technical University of Athens [Athens] (NTUA), Remote Sensing Laboratory [Barcelona] (RSLab), Universitat Politècnica de Catalunya [Barcelona] (UPC), Departamento de Química, Faculdade de Ciências da Universidade do Porto (FCUP), Universidade do Porto = University of Porto-Universidade do Porto = University of Porto, Laboratoire des champs magnétiques intenses (LCMI-GHMFL), Centre National de la Recherche Scientifique (CNRS), Laboratoire de Météorologie Physique (LaMP), Institut national des sciences de l'Univers (INSU - CNRS)-Université Clermont Auvergne [2017-2020] (UCA [2017-2020])-Centre National de la Recherche Scientifique (CNRS), Ludwig-Maximilians-Universität München (LMU), Universität Potsdam, Università degli Studi dell'Aquila (UNIVAQ)-Università degli Studi dell'Aquila (UNIVAQ), Universidade do Porto-Universidade do Porto, Université Clermont Auvergne [2017-2020] (UCA [2017-2020])-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Universitat Politècnica de Catalunya. Departament de Teoria del Senyal i Comunicacions, Universitat Politècnica de Catalunya. RSLAB - Grup de Recerca en Teledetecció, C., Bokmann, U., Wandinger, A., Ansmann, V., Freudentaler, J., Bosenberg, V., Amiridi, A., Boselli, A., Delaval, DE TOMASI, Ferdinando, M., Frioud, I. V., Grigorov, A., Hagard, M., Horvat, M., Iarlori, L., Komguen, S., Kreipl, G., Larcheveque, V., Matthia, A., Papayanni, G., Pappalardo, F., Rocadenbosch, J. A., Rodrigue, J., Schneider, V., Shcherbacov, and M., Wiegner

Subjects
Teledetecció, 010504 meteorology & atmospheric sciences, Backscatter, Meteorology, aerosol, Materials Science (miscellaneous), Field of view, RAMAN LIDAR, 01 natural sciences, Industrial and Manufacturing Engineering, Aerosol backscatter, 010309 optics, Troposphere, 0103 physical sciences, INVERSION, Business and International Management, lidar, Laser beams, ComputingMilieux_MISCELLANEOUS, 0105 earth and related environmental sciences, Remote sensing, [SDU.OCEAN]Sciences of the Universe [physics]/Ocean, Atmosphere, algorithm, EARLINET, Institut für Mathematik, Inversion (meteorology), ATMOSPHERE, EXTINCTION PROFILES, Aerosol, Lidar, Enginyeria de la telecomunicació::Radiocomunicació i exploració electromagnètica::Teledetecció [Àrees temàtiques de la UPC], Environmental science, Algorithm
Abstract

An intercomparison of aerosol backscatter lidar algorithms was performed in 2001 within the framework of the European Aerosol Research Lidar Network to Establish an Aerosol Climatology (EARLINET). The objective of this research was to test the correctness of the algorithms and the influence of the lidar ratio used by the various lidar teams involved in the EARLINET for calculation of backscatter-coefficient profiles from the lidar signals. The exercise consisted of processing synthetic lidar signals of various degrees of difficulty. One of these profiles contained height- dependent lidar ratios to test the vertical influence of those profiles on the various retrieval algorithms. Furthermore, a realistic incomplete overlap of laser beam and receiver field of view was introduced to remind the teams to take great care in the nearest range to the lidar. The intercomparison was performed in three stages with increasing knowledge on the input parameters. First, only the lidar signals were distributed; this is the most realistic stage. Afterward the lidar ratio profiles and the reference values at calibration height were provided. The unknown height- dependent lidar ratio had the largest influence on the retrieval, whereas the unknown reference value was of minor importance. These results show the necessity of making additional independent measurements, which can provide us with a suitable approximation of the lidar ratio. The final stage proves in general, that the data evaluation schemes of the different groups of lidar systems work well. (C) 2004 Optical Society of America

Published
2004
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14. Unravelling Mn 4 Ca cluster vibrations in the S 1 , S 2 and S 3 states of the Kok-Joliot cycle of photosystem II.

Author

Capone M, Parisse G, Narzi D, and Guidoni L

Abstract

Vibrational spectroscopy serves as a powerful tool for characterizing intermediate states within the Kok-Joliot cycle. In this study, we employ a QM/MM molecular dynamics framework to calculate the room temperature infrared absorption spectra of the S 1 , S 2 , and S 3 states via the Fourier transform of the dipole time auto-correlation function. To better analyze the computational data and assign spectral peaks, we introduce an approach based on dipole-dipole correlation function of cluster moieties of the reaction center. Our analysis reveals variation in the infrared signature of the Mn 4 Ca cluster along the Kok-Joliot cycle, attributed to its increasing symmetry and rigidity resulting from the rising oxidation state of the Mn ions. Furthermore, we successfully assign the debated contributions in the frequency range around 600 cm -1 . This computational methodology provides valuable insights for deciphering experimental infrared spectra and understanding the water oxidation process in both biological and artificial systems.

Published
2024
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15. Demonstrating Agreement between Radio and Fluorescence Measurements of the Depth of Maximum of Extensive Air Showers at the Pierre Auger Observatory.

Author

Abdul Halim A, Abreu P, Aglietta M, Allekotte I, Cheminant KA, Almela A, Aloisio R, Alvarez-Muñiz J, Yebra JA, Anastasi GA, Anchordoqui L, Andrada B, Andringa S, Anukriti, Apollonio L, Aramo C, Ferreira PRA, Arnone E, Velázquez JCA, Assis P, Avila G, Avocone E, Bakalova A, Barbato F, Mocellin AB, Bellido JA, Berat C, Bertaina ME, Bhatta G, Bianciotto M, Biermann PL, Binet V, Bismark K, Bister T, Biteau J, Blazek J, Bleve C, Blümer J, Boháčová M, Boncioli D, Bonifazi C, Arbeletche LB, Borodai N, Brack J, Orchera PGB, Briechle FL, Bueno A, Buitink S, Buscemi M, Büsken M, Bwembya A, Caballero-Mora KS, Cabana-Freire S, Caccianiga L, Caruso R, Castellina A, Catalani F, Cataldi G, Cazon L, Cerda M, Cermenati A, Chinellato JA, Chudoba J, Chytka L, Clay RW, Cerutti ACC, Colalillo R, Coleman A, Coluccia MR, Conceição R, Condorelli A, Consolati G, Conte M, Convenga F, Dos Santos DC, Costa PJ, Covault CE, Cristinziani M, Sanchez CSC, Dasso S, Daumiller K, Dawson BR, de Almeida RM, de Jesús J, de Jong SJ, Neto JRTM, De Mitri I, de Oliveira J, Franco DO, de Palma F, de Souza V, de Errico BPS, De Vito E, Del Popolo A, Deligny O, Denner N, Deval L, di Matteo A, Dobre M, Dobrigkeit C, D'Olivo JC, Mendes LMD, Dorosti Q, Dos Anjos JC, Dos Anjos RC, Ebr J, Ellwanger F, Emam M, Engel R, Epicoco I, Erdmann M, Etchegoyen A, Evoli C, Falcke H, Farmer J, Farrar G, Fauth AC, Fazzini N, Feldbusch F, Fenu F, Fernandes A, Fick B, Figueira JM, Filipčič A, Fitoussi T, Flaggs B, Fodran T, Fujii T, Fuster A, Galea C, Galelli C, García B, Gaudu C, Gemmeke H, Gesualdi F, Gherghel-Lascu A, Ghia PL, Giaccari U, Glombitza J, Gobbi F, Gollan F, Golup G, Berisso MG, Vitale PFG, Gongora JP, González JM, González N, Goos I, Góra D, Gorgi A, Gottowik M, Grubb TD, Guarino F, Guedes GP, Guido E, Gülzow L, Hahn S, Hamal P, Hampel MR, Hansen P, Harari D, Harvey VM, Haungs A, Hebbeker T, Hojvat C, Hörandel JR, Horvath P, Hrabovský M, Huege T, Insolia A, Isar PG, Janecek P, Jilek V, Johnsen JA, Jurysek J, Kampert KH, Keilhauer B, Khakurdikar A, Covilakam VVK, Klages HO, Kleifges M, Knapp F, Köhler J, Kunka N, Lago BL, Langner N, de Oliveira MAL, Lema-Capeans Y, Letessier-Selvon A, Lhenry-Yvon I, Lopes L, Lu L, Luce Q, Lundquist JP, Payeras AM, Majercakova M, Mandat D, Manning BC, Mantsch P, Marafico S, Mariani FM, Mariazzi AG, Mariş IC, Marsella G, Martello D, Martinelli S, Bravo OM, Martins MA, Mathes HJ, Matthews J, Matthiae G, Mayotte E, Mayotte S, Mazur PO, Medina-Tanco G, Meinert J, Melo D, Menshikov A, Merx C, Michal S, Micheletti MI, Miramonti L, Mollerach S, Montanet F, Morejon L, Morello C, Mulrey K, Mussa R, Namasaka WM, Negi S, Nellen L, Nguyen K, Nicora G, Niechciol M, Nitz D, Nosek D, Novotny V, Nožka L, Nucita A, Núñez LA, Oliveira C, Palatka M, Pallotta J, Panja S, Parente G, Paulsen T, Pawlowsky J, Pech M, Pękala J, Pelayo R, Pereira LAS, Martins EEP, Armand JP, Bertolli CP, Perrone L, Petrera S, Petrucci C, Pierog T, Pimenta M, Platino M, Pont B, Pothast M, Shahvar MP, Privitera P, Prouza M, Puyleart A, Querchfeld S, Rautenberg J, Ravignani D, Akim JVR, Reininghaus M, Ridky J, Riehn F, Risse M, Rizi V, de Carvalho WR, Rodriguez E, Rojo JR, Roncoroni MJ, Rossoni S, Roth M, Roulet E, Rovero AC, Ruehl P, Saftoiu A, Saharan M, Salamida F, Salazar H, Salina G, Gomez JDS, Sánchez F, Santos EM, Santos E, Sarazin F, Sarmento R, Sato R, Savina P, Schäfer CM, Scherini V, Schieler H, Schimassek M, Schimp M, Schmidt D, Scholten O, Schoorlemmer H, Schovánek P, Schröder FG, Schulte J, Schulz T, Sciutto SJ, Scornavacche M, Segreto A, Sehgal S, Shivashankara SU, Sigl G, Silli G, Sima O, Simkova K, Simon F, Smau R, Šmída R, Sommers P, Soriano JF, Squartini R, Stadelmaier M, Stanič S, Stasielak J, Stassi P, Strähnz S, Straub M, Suomijärvi T, Supanitsky AD, Svozilikova Z, Szadkowski Z, Tairli F, Tapia A, Taricco C, Timmermans C, Tkachenko O, Tobiska P, Peixoto CJT, Tomé B, Torrès Z, Travaini A, Travnicek P, Trimarelli C, Tueros M, Unger M, Vaclavek L, Vacula M, Galicia JFV, Valore L, Varela E, Vásquez-Ramírez A, Veberič D, Ventura C, Quispe IDV, Verzi V, Vicha J, Vink J, Vorobiov S, Watanabe C, Watson AA, Weindl A, Wiencke L, Wilczyński H, Wittkowski D, Wundheiler B, Yue B, Yushkov A, Zapparrata O, Zas E, Zavrtanik D, and Zavrtanik M

Abstract

We show, for the first time, radio measurements of the depth of shower maximum (X_{max}) of air showers induced by cosmic rays that are compared to measurements of the established fluorescence method at the same location. Using measurements at the Pierre Auger Observatory we show full compatibility between our radio and the previously published fluorescence dataset, and between a subset of air showers observed simultaneously with both radio and fluorescence techniques, a measurement setup unique to the Pierre Auger Observatory. Furthermore, we show radio X_{max} resolution as a function of energy and demonstrate the ability to make competitive high-resolution X_{max} measurements with even a sparse radio array. With this, we show that the radio technique is capable of cosmic-ray mass composition studies, both at Auger and at other experiments.

Published
2024
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16. Limits to Gauge Coupling in the Dark Sector Set by the Nonobservation of Instanton-Induced Decay of Super-Heavy Dark Matter in the Pierre Auger Observatory Data.

Author

Abreu P, Aglietta M, Albury JM, Allekotte I, Almeida Cheminant K, Almela A, Aloisio R, Alvarez-Muñiz J, Alves Batista R, Ammerman Yebra J, Anastasi GA, Anchordoqui L, Andrada B, Andringa S, Aramo C, Araújo Ferreira PR, Arnone E, Arteaga Velázquez JC, Asorey H, Assis P, Avila G, Avocone E, Badescu AM, Bakalova A, Balaceanu A, Barbato F, Bellido JA, Berat C, Bertaina ME, Bhatta G, Biermann PL, Binet V, Bismark K, Bister T, Biteau J, Blazek J, Bleve C, Blümer J, Boháčová M, Boncioli D, Bonifazi C, Bonneau Arbeletche L, Borodai N, Botti AM, Brack J, Bretz T, Brichetto Orchera PG, Briechle FL, Buchholz P, Bueno A, Buitink S, Buscemi M, Büsken M, Caballero-Mora KS, Caccianiga L, Canfora F, Caracas I, Caruso R, Castellina A, Catalani F, Cataldi G, Cazon L, Cerda M, Chinellato JA, Chudoba J, Chytka L, Clay RW, Cobos Cerutti AC, Colalillo R, Coleman A, Coluccia MR, Conceição R, Condorelli A, Consolati G, Contreras F, Convenga F, Correia Dos Santos D, Covault CE, Dasso S, Daumiller K, Dawson BR, Day JA, de Almeida RM, de Jesús J, de Jong SJ, de Mello Neto JRT, De Mitri I, de Oliveira J, de Oliveira Franco D, de Palma F, de Souza V, De Vito E, Del Popolo A, Del Río M, Deligny O, Deval L, di Matteo A, Dobre M, Dobrigkeit C, D'Olivo JC, Domingues Mendes LM, Dos Anjos RC, Dova MT, Ebr J, Engel R, Epicoco I, Erdmann M, Escobar CO, Etchegoyen A, Falcke H, Farmer J, Farrar G, Fauth AC, Fazzini N, Feldbusch F, Fenu F, Fick B, Figueira JM, Filipčič A, Fitoussi T, Fodran T, Fujii T, Fuster A, Galea C, Galelli C, García B, Garcia Vegas AL, Gemmeke H, Gesualdi F, Gherghel-Lascu A, Ghia PL, Giaccari U, Giammarchi M, Glombitza J, Gobbi F, Gollan F, Golup G, Gómez Berisso M, Gómez Vitale PF, Gongora JP, González JM, González N, Goos I, Góra D, Gorgi A, Gottowik M, Grubb TD, Guarino F, Guedes GP, Guido E, Hahn S, Hamal P, Hampel MR, Hansen P, Harari D, Harvey VM, Haungs A, Hebbeker T, Heck D, Hill GC, Hojvat C, Hörandel JR, Horvath P, Hrabovský M, Huege T, Insolia A, Isar PG, Janecek P, Johnsen JA, Jurysek J, Kääpä A, Kampert KH, Keilhauer B, Khakurdikar A, Kizakke Covilakam VV, Klages HO, Kleifges M, Kleinfeller J, Knapp F, Kunka N, Lago BL, Langner N, Leigui de Oliveira MA, Lenok V, Letessier-Selvon A, Lhenry-Yvon I, Lo Presti D, Lopes L, López R, Lu L, Luce Q, Lundquist JP, Machado Payeras A, Mancarella G, Mandat D, Manning BC, Manshanden J, Mantsch P, Marafico S, Mariani FM, Mariazzi AG, Mariş IC, Marsella G, Martello D, Martinelli S, Martínez Bravo O, Mastrodicasa M, Mathes HJ, Matthews J, Matthiae G, Mayotte E, Mayotte S, Mazur PO, Medina-Tanco G, Melo D, Menshikov A, Michal S, Micheletti MI, Miramonti L, Mollerach S, Montanet F, Morejon L, Morello C, Mostafá M, Müller AL, Muller MA, Mulrey K, Mussa R, Muzio M, Namasaka WM, Nasr-Esfahani A, Nellen L, Nicora G, Niculescu-Oglinzanu M, Niechciol M, Nitz D, Norwood I, Nosek D, Novotny V, Nožka L, Nucita A, Núñez LA, Oliveira C, Palatka M, Pallotta J, Papenbreer P, Parente G, Parra A, Pawlowsky J, Pech M, Pękala J, Pelayo R, Peña-Rodriguez J, Pereira Martins EE, Perez Armand J, Pérez Bertolli C, Perrone L, Petrera S, Petrucci C, Pierog T, Pimenta M, Pirronello V, Platino M, Pont B, Pothast M, Privitera P, Prouza M, Puyleart A, Querchfeld S, Rautenberg J, Ravignani D, Reininghaus M, Ridky J, Riehn F, Risse M, Rizi V, Rodrigues de Carvalho W, Rodriguez Rojo J, Roncoroni MJ, Rossoni S, Roth M, Roulet E, Rovero AC, Ruehl P, Saftoiu A, Saharan M, Salamida F, Salazar H, Salina G, Sanabria Gomez JD, Sánchez F, Santos EM, Santos E, Sarazin F, Sarmento R, Sarmiento-Cano C, Sato R, Savina P, Schäfer CM, Scherini V, Schieler H, Schimassek M, Schimp M, Schlüter F, Schmidt D, Scholten O, Schoorlemmer H, Schovánek P, Schröder FG, Schulte J, Schulz T, Sciutto SJ, Scornavacche M, Segreto A, Sehgal S, Shellard RC, Sigl G, Silli G, Sima O, Smau R, Šmída R, Sommers P, Soriano JF, Squartini R, Stadelmaier M, Stanca D, Stanič S, Stasielak J, Stassi P, Streich A, Suárez-Durán M, Sudholz T, Suomijärvi T, Supanitsky AD, Szadkowski Z, Tapia A, Taricco C, Timmermans C, Tkachenko O, Tobiska P, Todero Peixoto CJ, Tomé B, Torrès Z, Travaini A, Travnicek P, Trimarelli C, Tueros M, Ulrich R, Unger M, Vaclavek L, Vacula M, Valdés Galicia JF, Valore L, Varela E, Vásquez-Ramírez A, Veberič D, Ventura C, Vergara Quispe ID, Verzi V, Vicha J, Vink J, Vorobiov S, Wahlberg H, Watanabe C, Watson AA, Weindl A, Wiencke L, Wilczyński H, Wittkowski D, Wundheiler B, Yushkov A, Zapparrata O, Zas E, Zavrtanik D, Zavrtanik M, and Zehrer L

Abstract

Instantons, which are nonperturbative solutions to Yang-Mills equations, provide a signal for the occurrence of quantum tunneling between distinct classes of vacua. They can give rise to decays of particles otherwise forbidden. Using data collected at the Pierre Auger Observatory, we search for signatures of such instanton-induced processes that would be suggestive of super-heavy particles decaying in the Galactic halo. These particles could have been produced during the post-inflationary epoch and match the relic abundance of dark matter inferred today. The nonobservation of the signatures searched for allows us to derive a bound on the reduced coupling constant of gauge interactions in the dark sector: α&#95;{X}≲0.09, for 10^{9}≲M&#95;{X}/GeV<10^{19}. Conversely, we obtain that, for instance, a reduced coupling constant α&#95;{X}=0.09 excludes masses M&#95;{X}≳3×10^{13}  GeV. In the context of dark matter production from gravitational interactions alone, we illustrate how these bounds are complementary to those obtained on the Hubble rate at the end of inflation from the nonobservation of tensor modes in the cosmological microwave background.

Published
2023
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17. Features of the Energy Spectrum of Cosmic Rays above 2.5×10^{18}  eV Using the Pierre Auger Observatory.

Author

Aab A, Abreu P, Aglietta M, Albury JM, Allekotte I, Almela A, Alvarez Castillo J, Alvarez-Muñiz J, Alves Batista R, Anastasi GA, Anchordoqui L, Andrada B, Andringa S, Aramo C, Araújo Ferreira PR, Asorey H, Assis P, Avila G, Badescu AM, Bakalova A, Balaceanu A, Barbato F, Barreira Luz RJ, Becker KH, Bellido JA, Berat C, Bertaina ME, Bertou X, Biermann PL, Bister T, Biteau J, Blanco A, Blazek J, Bleve C, Boháčová M, Boncioli D, Bonifazi C, Bonneau Arbeletche L, Borodai N, Botti AM, Brack J, Bretz T, Briechle FL, Buchholz P, Bueno A, Buitink S, Buscemi M, Caballero-Mora KS, Caccianiga L, Calcagni L, Cancio A, Canfora F, Caracas I, Carceller JM, Caruso R, Castellina A, Catalani F, Cataldi G, Cazon L, Cerda M, Chinellato JA, Choi K, Chudoba J, Chytka L, Clay RW, Cobos Cerutti AC, Colalillo R, Coleman A, Coluccia MR, Conceição R, Condorelli A, Consolati G, Contreras F, Convenga F, Covault CE, Dasso S, Daumiller K, Dawson BR, Day JA, de Almeida RM, de Jesús J, de Jong SJ, De Mauro G, de Mello Neto JRT, De Mitri I, de Oliveira J, de Oliveira Franco D, de Souza V, De Vito E, Debatin J, Del Río M, Deligny O, Dembinski H, Dhital N, Di Giulio C, Di Matteo A, Díaz Castro ML, Dobrigkeit C, D'Olivo JC, Dorosti Q, Dos Anjos RC, Dova MT, Ebr J, Engel R, Epicoco I, Erdmann M, Escobar CO, Etchegoyen A, Falcke H, Farmer J, Farrar G, Fauth AC, Fazzini N, Feldbusch F, Fenu F, Fick B, Figueira JM, Filipčič A, Fodran T, Freire MM, Fujii T, Fuster A, Galea C, Galelli C, García B, Garcia Vegas AL, Gemmeke H, Gesualdi F, Gherghel-Lascu A, Ghia PL, Giaccari U, Giammarchi M, Giller M, Glombitza J, Gobbi F, Gollan F, Golup G, Gómez Berisso M, Gómez Vitale PF, Gongora JP, González N, Goos I, Góra D, Gorgi A, Gottowik M, Grubb TD, Guarino F, Guedes GP, Guido E, Hahn S, Halliday R, Hampel MR, Hansen P, Harari D, Harvey VM, Haungs A, Hebbeker T, Heck D, Hill GC, Hojvat C, Hörandel JR, Horvath P, Hrabovský M, Huege T, Hulsman J, Insolia A, Isar PG, Johnsen JA, Jurysek J, Kääpä A, Kampert KH, Keilhauer B, Kemp J, Klages HO, Kleifges M, Kleinfeller J, Köpke M, Kukec Mezek G, Lago BL, LaHurd D, Lang RG, Leigui de Oliveira MA, Lenok V, Letessier-Selvon A, Lhenry-Yvon I, Lo Presti D, Lopes L, López R, Lorek R, Luce Q, Lucero A, Machado Payeras A, Malacari M, Mancarella G, Mandat D, Manning BC, Manshanden J, Mantsch P, Marafico S, Mariazzi AG, Mariş IC, Marsella G, Martello D, Martinez H, Martínez Bravo O, Mastrodicasa M, Mathes HJ, Matthews J, Matthiae G, Mayotte E, Mazur PO, Medina-Tanco G, Melo D, Menshikov A, Merenda KD, Michal S, Micheletti MI, Miramonti L, Mockler D, Mollerach S, Montanet F, Morello C, Mostafá M, Müller AL, Muller MA, Mulrey K, Mussa R, Muzio M, Namasaka WM, Nellen L, Nguyen PH, Niculescu-Oglinzanu M, Niechciol M, Nitz D, Nosek D, Novotny V, Nožka L, Nucita A, Núñez LA, Palatka M, Pallotta J, Panetta MP, Papenbreer P, Parente G, Parra A, Pech M, Pedreira F, Pȩkala J, Pelayo R, Peña-Rodriguez J, Perez Armand J, Perlin M, Perrone L, Peters C, Petrera S, Pierog T, Pimenta M, Pirronello V, Platino M, Pont B, Pothast M, Privitera P, Prouza M, Puyleart A, Querchfeld S, Rautenberg J, Ravignani D, Reininghaus M, Ridky J, Riehn F, Risse M, Ristori P, Rizi V, Rodrigues de Carvalho W, Rodriguez Fernandez G, Rodriguez Rojo J, Roncoroni MJ, Roth M, Roulet E, Rovero AC, Ruehl P, Saffi SJ, Saftoiu A, Salamida F, Salazar H, Salina G, Sanabria Gomez JD, Sánchez F, Santos EM, Santos E, Sarazin F, Sarmento R, Sarmiento-Cano C, Sato R, Savina P, Schäfer C, Scherini V, Schieler H, Schimassek M, Schimp M, Schlüter F, Schmidt D, Scholten O, Schovánek P, Schröder FG, Schröder S, Schulz A, Sciutto SJ, Scornavacche M, Shellard RC, Sigl G, Silli G, Sima O, Šmída R, Sommers P, Soriano JF, Souchard J, Squartini R, Stadelmaier M, Stanca D, Stanič S, Stasielak J, Stassi P, Streich A, Suárez-Durán M, Sudholz T, Suomijärvi T, Supanitsky AD, Šupík J, Szadkowski Z, Taboada A, Tapia A, Timmermans C, Tkachenko O, Tobiska P, Todero Peixoto CJ, Tomé B, Torralba Elipe G, Travaini A, Travnicek P, Trimarelli C, Trini M, Tueros M, Ulrich R, Unger M, Urban M, Vaclavek L, Vacula M, Valdés Galicia JF, Valiño I, Valore L, van Vliet A, Varela E, Vargas Cárdenas B, Vásquez-Ramírez A, Veberič D, Ventura C, Vergara Quispe ID, Verzi V, Vicha J, Villaseñor L, Vink J, Vorobiov S, Wahlberg H, Watson AA, Weber M, Weindl A, Wiencke L, Wilczyński H, Winchen T, Wirtz M, Wittkowski D, Wundheiler B, Yushkov A, Zapparrata O, Zas E, Zavrtanik D, Zavrtanik M, Zehrer L, Zepeda A, Ziolkowski M, and Zuccarello F

Abstract

We report a measurement of the energy spectrum of cosmic rays above 2.5×10^{18}  eV based on 215 030 events. New results are presented: at about 1.3×10^{19}  eV, the spectral index changes from 2.51±0.03(stat)±0.05(syst) to 3.05±0.05(stat)±0.10(syst), evolving to 5.1±0.3(stat)±0.1(syst) beyond 5×10^{19}  eV, while no significant dependence of spectral features on the declination is seen in the accessible range. These features of the spectrum can be reproduced in models with energy-dependent mass composition. The energy density in cosmic rays above 5×10^{18}  eV is [5.66±0.03(stat)±1.40(syst)]×10^{53}  erg Mpc^{-3}.

Published
2020
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18. The Basal Ganglia: More than just a switching device.

Author

Florio TM, Scarnati E, Rosa I, Di Censo D, Ranieri B, Cimini A, Galante A, and Alecci M

Subjects
Animals, Cerebral Cortex cytology, Humans, Basal Ganglia physiology, Cerebral Cortex physiology, Executive Function physiology, Motor Activity physiology, Neural Pathways physiology
Abstract

The basal ganglia consist of a variety of subcortical nuclei engaged in motor control and executive functions, such as motor learning, behavioral control, and emotion. The striatum, a major basal ganglia component, is particularly useful for cognitive planning of purposive motor acts owing to its structural features and the neuronal circuitry established with the cerebral cortex. Recent data indicate emergent functions played by the striatum. Indeed, cortico-striatal circuits carrying motor information are paralleled by circuits originating from associative and limbic territories, which are functionally integrated in the striatum. Functional integration between brain areas is achieved through patterns of coherent activity. Coherence belonging to cortico-basal ganglia circuits is also present in Parkinson's disease patients. Excessive synchronization occurring in this pathology is reduced by dopaminergic therapies. The mechanisms through which the dopaminergic effects may be addressed are the object of several ongoing investigations. Overall, the bulk of data reported in recent years has provided new vistas concerning basal ganglia role in the organization and control of movement and behavior, both in physiological and pathological conditions. In this review, basal ganglia functions involved in the organization of main movement categories and behaviors are critically discussed. Comparatively, the multiplicity of Parkinson's disease symptomatology is also revised., (© 2018 John Wiley & Sons Ltd.)

Published
2018
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19. Electronic resonances in broadband stimulated Raman spectroscopy.

Author

Batignani G, Pontecorvo E, Giovannetti G, Ferrante C, Fumero G, and Scopigno T

Abstract

Spontaneous Raman spectroscopy is a formidable tool to probe molecular vibrations. Under electronic resonance conditions, the cross section can be selectively enhanced enabling structural sensitivity to specific chromophores and reaction centers. The addition of an ultrashort, broadband femtosecond pulse to the excitation field allows for coherent stimulation of diverse molecular vibrations. Within such a scheme, vibrational spectra are engraved onto a highly directional field, and can be heterodyne detected overwhelming fluorescence and other incoherent signals. At variance with spontaneous resonance Raman, however, interpreting the spectral information is not straightforward, due to the manifold of field interactions concurring to the third order nonlinear response. Taking as an example vibrational spectra of heme proteins excited in the Soret band, we introduce a general approach to extract the stimulated Raman excitation profiles from complex spectral lineshapes. Specifically, by a quantum treatment of the matter through density matrix description of the third order nonlinear polarization, we identify the contributions which generate the Raman bands, by taking into account for the cross section of each process.

Published
2016
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