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Ménesguen, Y., M. - C. Lépy, J. M. Sampaio, J. P. Marques, F. Parente, M. Guerra, P. Indelicato, J. P. Santos, P. Hönicke, and B. Beckhoff. "{A combined experimental and theoretical approach to determine X-ray atomic fundamental quantities of tin}." X-Ray Spectrom. 47 (2018): 341-351. Abstract
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Mayo, R., M. Ortiz, F. Parente, and J. P. Santos. "Experimental and theoretical transition probabilities for lines arising from the 6p configurations of Au II." Journal of Physics B: Atomic, Molecular and Optical Physics 40 (2007): 4651. AbstractWebsite

Experimental relative transition probabilities for the 16 more pro-eminent lines arising from the 6p configurations of Au II were determined from the emission-line intensities in a laser-produced plasma. The experiment was carried out using a Cu-Au alloy with 10% Au content in order to obtain an optically thin plasma. Transition probabilities were placed on an absolute scale by using theoretical lifetimes calculated in this work, line-strength sum rules and Boltzmann plot. A comparison has been conducted between present experimental results, the theoretical data available and new calculations with the multi-configuration Dirac-Fock method reported in this work, as well as a study of the plasma conditions.

Mayo, R., M. Ortiz, F. Parente, and J. P. Santos. "Experimental and theoretical transition probabilities for lines arising from the 6p configurations of Au II." Journal of Physics B: Atomic, Molecular and Optical Physics 40 (2007): 4651. AbstractWebsite
Experimental relative transition probabilities for the 16 more pro-eminent lines arising from the 6p configurations of Au II were determined from the emission-line intensities in a laser-produced plasma. The experiment was carried out using a Cu-Au alloy with 10% Au content in order to obtain an optically thin plasma. Transition probabilities were placed on an absolute scale by using theoretical lifetimes calculated in this work, line-strength sum rules and Boltzmann plot. A comparison has been conducted between present experimental results, the theoretical data available and new calculations with the multi-configuration Dirac-Fock method reported in this work, as well as a study of the plasma conditions.
Martins, M. C., J. P. Santos, A. M. Costa, and F. Parente. "Transition wavelengths and probabilities for spectral lines of Zr III." The European Physical Journal D 39 (2006): 167-172. AbstractWebsite

Wavelengths and oscillator strengths for all dipole-allowed fine-structure transitions in Zr III have been calculated within the Multi-Configuration Dirac-Fock method with QED corrections. These transitions are included in the spectrum of some chemically peculiar stars, like the B-type star Lupi observed by the Hubble space telescope. The results are compared to existing experimental and semi-empirical data. Corr

Martins, M. C., J. P. Marques, A. M. Costa, J. P. Santos, F. Parente, S. Schlesser, Le E. - O. Bigot, and P. Indelicato. "Production and decay of sulfur excited species in an electron-cyclotron-resonance ion-source plasma." Physical Review A (Atomic, Molecular, and Optical Physics) 80 (2009): 032501. AbstractWebsite
The most important processes for the creation of S12+ to S14+ ions excited states from the ground configurations of S9+ to S14+ ions in an electron cyclotron resonance ion source, leading to the emission of K x-ray lines, are studied. Theoretical values for inner-shell excitation and ionization cross sections, including double-KL and triple-KLL ionizations, transition probabilities and energies for the de-excitation processes, are calculated in the framework of the multiconfiguration Dirac-Fock method. With reasonable assumptions about the electron energy distribution, a theoretical Kalpha x-ray spectrum is obtained, which is compared to recent experimental data.
Martins, M. C., J. P. Santos, A. M. Costa, and F. Parente. "Transition wavelengths and probabilities for spectral lines of Zr III." The European Physical Journal D 39 (2006): 167-172. AbstractWebsite
Wavelengths and oscillator strengths for all dipole-allowed fine-structure transitions in Zr III have been calculated within the Multi-Configuration Dirac-Fock method with QED corrections. These transitions are included in the spectrum of some chemically peculiar stars, like the B-type star Lupi observed by the Hubble space telescope. The results are compared to existing experimental and semi-empirical data.
Martins, M. C., A. M. Costa, J. P. Santos, F. Parente, and P. Indelicato. "Relativistic calculation of two-electron one-photon and hypersatellite transition energies for 12<=Z<=30 elements." Journal of Physics B: Atomic and Molecular Physics 37 (2004): 3785-3795. AbstractWebsite

Energies of two-electron one-photon transitions from initial double K-hole states were computed using the Dirac–Fock model. The transition energies of competing processes, the Ka hypersatellites, were also computed. The results are compared with experiment and to other theoretical calculations.

Martins, M. C., J. P. Marques, A. M. Costa, J. P. Santos, F. Parente, S. Schlesser, E. O. Le Bigot, and P. Indelicato. "Production and decay of sulfur excited species in an electron-cyclotron-resonance ion-source plasma." Physical Review A 80 (2009): 032501. AbstractWebsite

The most important processes for the creation of S12+ to S14+ ions excited states from the ground configurations of S9+ to S14+ ions in an electron cyclotron resonance ion source, leading to the emission of K x-ray lines, are studied. Theoretical values for inner-shell excitation and ionization cross sections, including double-KL and triple-KLL ionizations, transition probabilities and energies for the de-excitation processes, are calculated in the framework of the multiconfiguration Dirac-Fock method. With reasonable assumptions about the electron energy distribution, a theoretical Kalpha x-ray spectrum is obtained, which is compared to recent experimental data.

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.

Marques, J. P., P. Indelicato, F. Parente, J. M. Sampaio, and J. P. Santos. "Ground-state Landé <span class="aps-inline-formula"><math xmlns="http://www.w3.org/1998/Math/MathML"><mi>g</mi></math></span> factors for selected ions along the boron isoelectronic sequence." Physical Review A 94 (2016): 042504. AbstractWebsite

Land\'e $g$ factors for the fine-structure $1{s}^{2}2{s}^{2}2p\phantom{\rule{0.16em}{0ex}}^{2}P_{1/2}$ and $^{2}P_{3/2}$ levels in the boron isoelectronic sequence for selected $Z$ values have been calculated using the multiconfiguration Dirac-Fock method with both quantum-electrodynamic and electronic correlation corrections included. All-order Breit and vacuum polarization corrections were included in the calculation, with a fully optimized active set wave function. The results are compared with the available theoretical data, showing a very good agreement.

Marques, J., F. Parente, A. Costa, M. Martins, P. Indelicato, and J. P. Santos. "Decay of the 1s^{2}2s3p ^{3}P_{0} level in Be-like ions." Phys. Rev. A 86 (2012): 052521. AbstractWebsite

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Marques, J. P., M. Guerra, F. Parente, J. P. Santos, P. Indelicato, and J. M. Sampaio. "K-shell width, fluorescence yield, and Kβ/ Kαintensity ratio calculation for Fe in the Dirac-Fock approach." Journal of Physics: Conference Series 635 (2015): 092094-2. AbstractWebsite
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Marques, J. P., P. Indelicato, F. Parente, J. M. Sampaio, and J. P. Santos. "Ground-state Landé g factors for selected ions along the boron isoelectronic sequence." Physical Review A 94 (2016): 042504. AbstractWebsite

Land\'e $g$ factors for the fine-structure $1{s}^{2}2{s}^{2}2p\phantom{\rule{0.16em}{0ex}}^{2}P_{1/2}$ and $^{2}P_{3/2}$ levels in the boron isoelectronic sequence for selected $Z$ values have been calculated using the multiconfiguration Dirac-Fock method with both quantum-electrodynamic and electronic correlation corrections included. All-order Breit and vacuum polarization corrections were included in the calculation, with a fully optimized active set wave function. The results are compared with the available theoretical data, showing a very good agreement.

Marques, J. P., M. C. Martins, A. M. Costa, P. Indelicato, F. Parente, and J. P. Santos. "Theoretical determination of K X-ray transition energy and probability values for highly charged (He- through B-like) Nd, Sm, Gd, Dy, Er, and Yb ions." Radiat. Phys. Chem. 154 (2019): 17-20. Abstract

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Manso, M., S. Pessanha, M. Guerra, J. L. Figueirinhas, J. P. Santos, and M. L. Carvalho. "Unveiling the Third Secret of Fátima: μ-XRF quantitative characterization and 2D elemental mapping." Spectrochimica Acta Part B: Atomic Spectroscopy 130 (2017): 35-38. AbstractWebsite

Spectrochimica Acta Part B: Atomic Spectroscopy, 130 (2017) 35-38. doi:10.1016/j.sab.2017.02.006

Madeira, T. I., J. M. Sampaio, M. Guerra, F. Parente, P. Indelicato, J. P. Santos, and J. P. Marques. "Relativistic calculation of K-, L- and M-shell x-ray fluorescence yields for Ba." Physica Scripta 90 (2015): 1-3. AbstractWebsite

Physica Scripta, 90(2015) 054009. doi:10.1088/0031-8949/90/5/054009

Machado, J., C. I. Szabo, J. P. Santos, P. Amaro, M. Guerra, A. Gumberidze, Guojie Bian, J. M. Isac, and P. Indelicato. "{High-precision measurements of $n=2\rightarrow n=1$ transition energies and level widths in He- and Be-like argon ions}." Phys. Rev. 97 (2018): 032517. Abstract
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Machado, Jorge, {Patrícia M. S. } Carvalho, Ana Félix, Delfin Doutel, {José Paulo} Santos, {Maria Luísa} Carvalho, and Sofia Pessanha. "Accuracy improvement in XRF analysis for the quantification of elements ranging from tenths to thousands μg g-1in human tissues using different matrix reference materials." Journal of Analytical Atomic Spectrometry 35 (2020): 2920-2927. Abstract

In this work, we aim at achieving the most accurate quantitative determination of elements in human tissues by means of X-ray Fluorescence spectrometry using the external calibration approach. A calibration curve built using a set of certified reference materials (CRM) of animal tissue was compared with the one obtained with a set of CRMs of plants and leaves with lower atomic number Z but with correction of the matrix using the scattering peaks of the X-ray tube anode. Finally, a calibration curve combining the two sets of CRMs was built and the accuracy of the quantification using the three methods was compared and a more precise method of quantification was obtained. This improved approach was tested on five paired samples of normal and tumour human tissue. Despite the high heterogeneity of the samples, and given the improvement in accuracy of the measurements, significant differences were found in the elemental concentration of low-Z elements. This journal is

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Lopes, G., D. Tendeiro, J. P. Santos, and P. Vieira. "Monte Carlo Simulation of Radiation through the Human Retina Using Geant4.", 431-434. Vol. 41. Cham: Springer International Publishing, 2014. Abstract
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Lopes, G., D. Tendeiro, J. P. Santos, and P. Vieira. "Monte Carlo Simulation of Radiation through the Human Retina Using Geant4.", 431-434. Vol. 41. Cham: Springer International Publishing, 2014. Abstract
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Lopes, A., A. Gabriel, J. Machado, P. Ribeiro, R. Gomes, Jo M. P. o Coelho, C. O. Silva, C. P. Reis, J. P. Santos, and P. Vieira. "Multiple Source Phototherapy in Breast Cancer: A Viability Study." In 9th International Conference on Biomedical Electronics and Devices, 247-250. SCITEPRESS - Science and and Technology Publications, 2016. Abstract
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LIDON, FERNANDO CEBOLA, KARLIANA OLIVEIRA, CARLOS GALHANO, Mauro Guerra, MARIA MANUELA RIBEIRO, JOÃO PELICA, INÊS PATACO, JOSÉ COCHICHO RAMALHO, ANTÓNIO EDUARDO LEITÃO, ANA SOFIA ALMEIDA, PAULA SCOTTI CAMPOS, Ana Ribeiro-Barros, ISABEL P. PAIS, Maria Manuela Silva, Maria Luisa Carvalho, Jose Paulo Santos, MARIA FERNANDA PESSOA, and FERNANDO HENRIQUE REBOREDO. "{SELENIUM BIOFORTIFICATION OF RICE THROUGH FOLIAR APPLICATION WITH SELENITE AND SELENATE}." Experimental Agriculture (2018): 1-15. Abstract

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Kup Aylikci, N., J. M. Sampaio, A. Kahoul, V. Aylikci, İ. H. Karahan, M. Guerra, J. P. Santos, J. P. Marques, and E. Tirasoglu. "The investigation of K-shell fluorescence parameters of Zn-Fe alloys with different grain size and microstrain values." X-Ray Spectrometry 406 (2017): 1481-10. AbstractWebsite

It is known that zinc alloys with iron group metals have better corrosion resistance than pure zinc. Owing to the corrosion resistance of these alloys, Zn–Fe coatings are widely used in automotive industry...

Krauth, Julian J., Karsten Schuhmann, Marwan Abdou Ahmed, Fernando D. Amaro, Pedro Amaro, François Biraben, Tzu-Ling Chen, Daniel S. Covita, Andreas J. Dax, Marc Diepold, Luis M. P. Fernandes, Beatrice Franke, Sandrine Galtier, Andrea L. Gouvea, Johannes Götzfried, Thomas Graf, Theodor W. Hänsch, Jens Hartmann, Malte Hildebrandt, Paul Indelicato, Lucile Julien, Klaus Kirch, Andreas Knecht, Yi-Wei Liu, Jorge Machado, Cristina M. B. Monteiro, Françoise Mulhauser, Boris Naar, Tobias Nebel, François Nez, Joaquim M. F. dos Santos, José Paulo Santos, Csilla I. Szabo, David Taqqu, João F. C. A. Veloso, Jan Vogelsang, Andreas Voss, Birgit Weichelt, Randolf Pohl, Aldo Antognini, and Franz Kottmann. "Measuring the $\upalpha$-particle charge radius with muonic helium-4 ions." Nature 589 (2021): 527-531. AbstractWebsite
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