Export 444 results:
Sort by: Author Title Type [ Year  (Desc)]
2002
Inacio, P., C. J. Dias, J. N. Marat-Mendes, and T. Vieira. "Development of a biosensor based on a piezoelectric film." Advanced Materials Forum I. Vol. 230-2. 2002. 491-494. Abstract
n/a
Inacio, P., C. J. Dias, and J. N. Marat-Mendes. "Development of a biosensor based on a piezoelectric film." Advanced Materials Forum I. Ed. T. Vieira. Vol. 230-2. Key Engineering Materials, 230-2. 2002. 491-494. Abstract
n/a
Baptista, JL, Isabel Ferreira, Rodrigo Martins, Andréi L. Kholkin, Elvira Fortunato, S. Iakovlev, and V. Shvartsman. "Optical and photoelectric properties of PZT films for microelectronic applications." Key Engineering Materials. 230 (2002): 563-566. Abstract
n/a
Ley, L., AH Mahan, Y. Xu, E. Iwaniczko, DL Williamson, BP Nelson, Q. Wang, H. Umemoto, Y. Nozaki, and M. Kitazoe. "PART A." (2002). Abstract
n/a
Igreja, R., C. J. Dias, and J. N. Marat-Mendes. "Smart materials: The functional properties of ceramic/polymer composites and their relation to sol-gel powder preparation." Advanced Materials Forum I. Ed. T. Vieira. Vol. 230-2. Key Engineering Materials, 230-2. 2002. 177-180. Abstract
n/a
Igreja, R., C. J. Dias, and J. N. Marat-Mendes. "Smart materials: The functional properties of ceramic/polymer composites and their relation to sol-gel powder preparation." Advanced Materials Forum I. Ed. T. Vieira. Vol. 230-2. Key Engineering Materials, 230-2. 2002. 177-180. Abstract
n/a
Igreja, R., C. J. Dias, J. N. Marat-Mendes, and T. Vieira. "Smart materials: The functional properties of ceramic/polymer composites and their relation to sol-gel powder preparation." Advanced Materials Forum I. Vol. 230-2. 2002. 177-180. Abstract
n/a
Casella, C., H. Costantini, a. Lemut, B. Limata, D. Bemmerer, R. Bonetti, C. Broggini, L. Campajola, P. Cocconi, P. Corvisiero, J. Cruz, a. D'Onofrio, a. Formicola, Z. Fülöp, G. Gervino, L. Gialanella, a. Guglielmetti, C. Gustavino, G. Gyurky, a. Loiano, G. Imbriani, P. a. Jesus, M. Junker, P. Musico, a. Ordine, F. Parodi, M. Parolin, JV Pinto, P. Prati, J. P. Ribeiro, V. Roca, D. Rogalla, C. Rolfs, M. Romano, C. Rossi-Alvarez, a. Rottura, F. Schuemann, E. Somorjai, F. Strieder, F. Terrasi, H. P. Trautvetter, a. Vomiero, and S. Zavatarelli. "{A new setup for the underground study of capture reactions}." Nuclear Instruments and Methods in Physics Research, Section A: Accelerators, Spectrometers, Detectors and Associated Equipment. 489 (2002): 160-169. Abstract

For the study of astrophysically relevant capture reactions in the underground laboratory LUNA a new setup of high sensitivity has been implemented. The setup includes a windowless gas target, a 4$π$ BGO summing crystal, and beam calorimeters. The setup has been recently used to measure the d(p,$\gamma$)3He cross-section for the first time within its solar Gamow peak, i.e. down to 2.5keV c.m. energy. The features of the optimized setup are described. © 2002 Elsevier Science B.V. All rights reserved.

2001
Costa, A. M., M. C. Martins, J. P. Santos, P. Indelicato, and F. Parente. "Dirac-Fock Transition Energies and Radiative and Radiationless Transition Probabilities for Ar8+ to Ar16+ Ion Levels with K-Shell Hole." Atomic Data and Nuclear Data Tables. 79 (2001): 223-239. Abstract
n/a
Martins, M. C., A. M. Costa, J. P. Santos, P. Indelicato, and F. Parente. "Interpretation of X-ray spectra emitted by Ar ions in an ECR ion source." Journal of Physics B: Atomic and Molecular Physics. 34 (2001): 533-543. AbstractWebsite

We examine the most important processes leading to the creation of excited states from the ground configurations of Ar8+ to Ar16+ ions in an electron-cyclotron resonance ion source, which lead to the emission of K x-ray lines. Theoretical values for inner-shell excitation and ionization cross sections, including double KL ionization, transition probabilities and energies for the de-excitation processes, are calculated in the framework of the multi-configuration Dirac-Fock method. With reasonable assumptions about the electron energy distribution, a theoretical K x-ray spectrum is obtained, which reproduces very closely a recent experimental result.

Indelicato, P., G. C. Rodrigues, E. Lindroth, M. A. Ourdane, F. Parente, J. P. Santos, P. Patté, and J. Bieron. "Relativistic and many-body effects on total binding energies of Cesium and other highly-charged ion." Physica Scripta. T92 (2001): 327. Abstract

The determination of atomic masses from highly ionized atoms using Penning Traps requires precise values for electronic binding energies. In the present work, binding energies of several ions (from several elements) are calculated in the framework of two relativistic many-body methods: Relativistic Many-Body Perturbation Theory (RMBPT) and Multi-Configuration Dirac– Fock (MCDF). The ions studied in this work are: Cl (He and Li-like), Se (F and Ne-like), Cs (He, Be, Ne, Al, Cl, Ar, K, Kr, Xe-like and neutral Cs), Hg, Pb and U (Br and Kr-like). Some of them are presented in this paper. Cesium has been treated in more details, allowing for a systematic comparison between MCDF and RMBPT methods. The Cs ions binding energies allow for the determination of atomic Cs mass, which can be used in a QED-independent fine structure constant determination.

Indelicato, P., E. Lindroth, T. Beier, J. Bieron, A. M. Costa, I. Lindgren, J. P. Marques, A. M. Martenson-Pendrill, M. C. Martins, M. A. Ourdane, F. Parente, P. Patté, G. C. Rodrigues, S. Salomonson, and J. P. Santos. "Relativistic Calculations for Trapped Ions." Hyperfine Interactions. 132 (2001): 347-361. AbstractWebsite

We present recent results in the field of total binding energy calculations, Landщ factors, quantum electrodynamics corrections and lifetime that are of interest for ion traps and ion sources. We describe in detail MCDF and RMBPT calculation of ionic binding energies, which are needed for the determination of atomic masses from highly charged ion measurements. We also show new results concerning Landщ factor in 3-electron ions. Finally we describe how relativistic calculations can help understand the physics of heavy ion production ion sources.

Santos, J. P., P. Patté, F. Parente, and P. Indelicato. "Spontaneous relativistic two-photon decay rate mathematical expression in heliumlike systems." The European Physical Journal D. 13 (2001): 27-31. AbstractWebsite

We derive a theoretical expression for the two-photon emission rate of two-electron systems, in a form suitable for easy implementation in numerical calculations. Racah algebra techniques were used to extended previous work on two-photon emission in hydrogen-like systems to more complex ones. The obtained expression is, as far as we are aware, the first general expression that gives the spontaneous two-photon decay rates of helium-like systems for any combination of multipoles.

2000
Santos, J. P., J. P. Marques, F. Parente, P. Indelicato, and J. P. Desclaux. "Relativistic 2s1/2 (L1) atomic subshell radiationless transition probabilities for Yb and Hg." Atomic Data and Nuclear Data Tables. 76 (2000): 49-69. Abstract

Radiationless transition rates to L1 vacancy states have been calculated ab initio in the Dirac-Fock approximation. The calculations include quantum-electrodynamic corrections. Results in the jj coupling scheme for all possible L1 transitions are tabulated for elements Yb and Hg.

1999
Igreja, R., C. Dias, and J. Marat-Mendes. "Processing and characterization of sol-gel derived modified PbTiO(3) for ferroelectric composites." Ferroelectrics. 228 (1999): 99-109. Abstract
n/a
Igreja, R., C. Dias, and J. Marat-Mendes. "Processing and characterization of sol-gel derived modified PbTiO(3) for ferroelectric composites." Ferroelectrics. 228 (1999): 99-109. AbstractWebsite
n/a
Igreja, R., C. Dias, and J. Marat-Mendes. "Processing and characterization of sol-gel derived modified PbTiO(3) for ferroelectric composites." Ferroelectrics. 228 (1999): 99-109. Abstract
n/a
Santos, J. P., J. P. Marques, F. Parente, E. Lindroth, P. Indelicato, and J. P. Desclaux. "Relativistic 2s1/2 (L1) atomic subshell decay rates and fluorescence yields for Yb and Hg." Journal of Physics B: Atomic and Molecular Physics. 32 (1999): 2089. AbstractWebsite
n/a
1998
Santos, J. P., F. Parente, and P. Indelicato. "Application of B-splines finite basis sets to relativistic two-photon decay rates of 2s level in hydrogenic ions." The European Physical Journal D. 3 (1998): 43-52. AbstractWebsite

A theoretical study of the one- and two-photon spontaneous emission rates from the 2 s1/2 state of one-electron ions is presented. High-precision values of the relativistic emission rates for ions with nuclear charge Z up to 100 are obtained through the use of finite basis sets for the Dirac equation constructed from B-splines. Furthermore, we analyze the influence of the inclusion of quantum electrodynamics corrections in the initial and final state energies.

Igreja, R., C. J. Dias, J. N. Marat-Mendes, and NM White. "Development of ferroelectric ceramic/polymer composites for electro-active sensors applications." Eurosensors Xii, Vols 1 and 2. 1998. 473-476. Abstract
n/a
Igreja, R., C. J. Dias, J. N. Marat-Mendes, and NM White. "Development of ferroelectric ceramic/polymer composites for electro-active sensors applications." Eurosensors Xii, Vols 1 and 2. 1998. 473-476. Abstract
n/a
Santos, J. P., J. P. Marques, F. Parente, E. Lindroth, S. Boucard, and P. Indelicato. "Multiconfiguration Dirac-Fock calculation of 2s1/2-2p3/2 transition energies in highly ionized bismuth, thorium, and uranium." The European Physical Journal D. 1 (1998): 149-163. Abstract

Structure and QED effects for 2s1/2 and 2p3/2 levels are calculated for lithiumlike U89+ trough neonlike U82+, lithiumlike Th87+ trough neonlike Th80+ and lithiumlike Bi80+ trough neonlike Bi73+. The results of the first two sets are compared with recent measurements of the 2s1/2-2p3/2 transition energy in 3 to 10-electron ions. Good agreement with experiment is found for most of the observed lines. Forty-one possible transitions are calculated for each ion in the eight ionization states, in the experimental energy range. Twenty-eight of these transitions have not been observed, nor calculated previously. We also calculate transition rates, branching ratios, excitation and ionization cross sections and confirm that the thirteen experimental observed transitions correspond to the ones with highest relative intensities. However, we find nineteen more transitions that could be measured in a more sensitive experiment.X