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Grilo, Filipe, Chintan Shah, Steffen Kühn, René Steinbrügge, Keisuke Fujii, José Marques, Ming Feng Gu, José Paulo Santos, José Crespo R. López-Urrutia, and Pedro Amaro. "Comprehensive Laboratory Measurements Resolving the {LMM} Dielectronic Recombination Satellite Lines in Ne-like Fe xvii Ions." The Astrophysical Journal 913 (2021): 140. AbstractWebsite
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
Amaro, P., J. P. Santos, S. Bhattacharyya, T. K. Mukherjee, and J. K. Saha. "Stabilization method with the relativistic configuration-interaction calculation applied to two-electron resonances." Physical Review A 103 (2021). AbstractWebsite
Ensina, Ana, Patr{\'ı}cia M. Carvalho, Jorge Machado, Maria Lu{\'ı}sa Carvalho, Diogo Casal, Diogo Pais, José Paulo Santos, António A. Dias, and Sofia Pessanha. "Analysis of human tissues using Energy Dispersive X Ray Fluorescence – Dark matrix determination for the application to cancer research." Journal of Trace Elements in Medicine and Biology 68 (2021): 126837. AbstractWebsite
Wain, Alison, Diogo Castro, {Maria Fernanda} Rollo, Frederico Nogueira, Gon{\c c}alo Santos, {Maria Gra{\c da c}a} Filipe, Isabel Tissot, {Jorge Miguel} Sampaio, {José Paulo} Santos, Manuel Lemos, Marta Manso, Matthias Tissot, Mauro Guerra, Miles Oglethorpe, Pedro Amaro, Pedro Pedroso, Rui Silva, Sofia Pessanha, and {Tiago A. N. } Silva. Cultura Material, Cultura Científica: Património Industrial para o Futuro. Portugal: Faculdade de Ciências e Tecnologia, Universidade Nova de Lisboa, 2021. Abstract

Material, Culture, Scientific Culture: Industrial Heritage for the Future

Santos, J. P., Iulian Otel, Joao Silveira, Valentina Vassilenko, António Mata, Maria Luísa Carvalho, José Paulo Santos, and Sofia Pessanha. "Application of Unsupervised Multivariate Analysis Methods to Raman Spectroscopic Assessment of Human Dental Enamel." Computers (2021). AbstractWebsite
da Carvalho, {Patrícia Miguel Silva}, Fábio Leite, {A. L. M. } Silva, Sofia Pessanha, {Maria Luísa} Carvalho, {João F. C. A. } Veloso, and {José Paulo} Santos. "Elemental mapping of Portuguese ceramic pieces with a full-field XRF scanner based on a 2D-THCOBRA detector." European Physical Journal Plus 136 (2021). Abstract

In this work, we present a novel application of the full-field energy-dispersive X-ray fluorescence (EDXRF) imaging system based on a MicroPattern Gaseous Detector (2D-THCOBRA) in the cultural heritage field. The detector has an intrinsic imaging capability with spatial resolution of 400μmFWHM, and is energy sensitive, presenting an energy resolution of approximately 1keVFWHM at 5.9keV. The full-field XRF scanner based on the 2D-THCOBRA detector allows mapping the distribution of elements in large area samples with high detection efficiency (75 % at 5.9keV), being a very promising choice for elemental mapping analysis of large area cultural heritage samples. In this work, we have demonstrated the imaging capabilities of the full-field XRF scanner and used it to assess the restoration of a Portuguese faience piece.

Santos, J. P., Mauro Guerra, Jorge M. Sampaio, Gonçalo R. Vília, César A. Godinho, Daniel Pinheiro, Pedro Amaro, José P. Marques, Jorge Machado, Paul Indelicato, Fernando Parente, and José Paulo Santos. "Fundamental Parameters Related to Selenium K\alpha and K\beta Emission X-ray Spectra." Atoms (2021). AbstractWebsite
Togawa, M., S. Kühn, C. Shah, P. Amaro, R. Steinbrügge, J. Stierhof, N. Hell, M. Rosner, K. Fujii, M. Bissinger, R. Ballhausen, M. Hoesch, J. Seltmann, S. Park, F. Grilo, F. S. Porter, J. P. Santos, M. Chung, T. Stöhlker, J. Wilms, T. Pfeifer, G. V. Brown, M. A. Leutenegger, S. Bernitt, and Crespo J. R. López-Urrutia. "Observation of strong two-electron–one-photon transitions in few-electron ions." Physical Review A 102 (2020). AbstractWebsite
Ito, Y., T. Tochio, M. Yamashita, S. Fukushima, A. M. Vlaicu, J. P. Marques, J. M. Sampaio, M. Guerra, J. P. Santos, Ł. Syrocki, K. Słabkowska, E. WÈ©der, M. Polasik, J. Rzadkiewicz, P. Indelicato, Y. Ménesguen, M.-Ch. Lépy, and F. Parente. "Structure of K$\upalpha$1,2- and K$\upbeta$1,3-emission x-ray spectra for Se, Y, and Zr." Physical Review A 102 (2020). AbstractWebsite
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

Carvalho, Patr{\'ı}cia M. S., Sofia Pessanha, Jorge Machado, Ana Lu{\'ı}sa Silva, João Veloso, Diogo Casal, Diogo Pais, and José Paulo Santos. "Energy dispersive X-ray fluorescence quantitative analysis of biological samples with the external standard method." Spectrochimica Acta Part B: Atomic Spectroscopy 174 (2020): 105991. AbstractWebsite
Santos, J. P. "HCI 2018." X-Ray Spectrometry (2020). AbstractWebsite
Reboredo, {Fernando Henrique}, A. Barbosa, {Maria Manuela} Silva, {Maria Luisa} Carvalho, {José Paulo} Santos, {Maria Fernanda} Pessoa, Fernando Lidon, {José C. } Ramalho, and Mauro Guerra. "Mineral Content of Food Supplements of Plant Origin, by Energy Dispersive X-ray Fluorescence: A Risk Assessment." Exposure and Health 12 (2020): 917-927. Abstract

The aim of this study is to evaluate the elemental composition of six food supplements of plant origin, commonly sold in the Portuguese market, by energy dispersive X-ray fluorescence. The presence of arsenic in all the Maca, Ashwagandha, Camu-Camu and Hemp protein samples (except the generic form) is a reason of concern due to the long-term effects of As mainly in its inorganic form. Thus, great caution must be taken on some food supplements, particularly the cases of Moringa from Egypt and Yellow/Xpresso Maca, whose inorganic As concentrations are in line with the upper bound concentration for the 95th dietary exposure according to the European Food Safety Authority which is 0.64 μg/kg bw/day. In what regards Hemp protein, if the supplier’s daily intake recommendation (30 g) is followed, values as high as 1.75 μg/kg bw/day of inorganic As will be consumed, which are dangerously above the upper bound. In this case this specific supplement lot should be removed from the market. Also the consumption of Hemp protein leads to a daily intake of Mn above the Daily Reference Intake (DRI) and Adequate Intakes (AIs) for adults. The contamination of Goji berries by Pb is a reason for concern—organic berries contained 11.3 μg/g while berries derived from conventional agriculture 11.6 μg/g, leading to daily intake doses of 315.3 μg and 324.8 μg, respectively, if the recommended daily intake of 28 g is followed. Our findings point out to an inadequacy of the recommended intakes by the supplier vis a vis the concentrations observed, greatly increasing the risk for public health.

Santos, J. P., J. Machado, Guojie Bian, Nancy Paul, M. Trassinelli, P. Amaro, M. Guerra, C. I. Szabo, A. Gumberidze, J. M. Isac, J. P. Santos, J. P. Desclaux, and P. Indelicato. "Reference-free measurements of the 1s2s2p2P1/2,3/2o\rightarrow1s22s2S1/2 and 1s2s2p4P5/2\rightarrow1s22s2S1/2 transition energies and widths in lithiumlike sulfur and argon ions." Physical Review A (2020). AbstractWebsite
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


Zeeshan, Faisal, Joanna Hoszowska, {Jean Claude} Dousse, Dimosthenis Sokaras, {Tsu Chien} Weng, Roberto Alonso-Mori, Matjaz Kav{\v c}i{\v c}, Mauro Guerra, {Jorge Miguel} Sampaio, Fernando Parente, Paul Indelicato, {José Pires} Marques, and {José Paulo} Santos. "Diagram, valence-to-core, and hypersatellite Kβ X-ray transitions in metallic chromium." X-Ray Spectrometry 48 (2019): 351-359. Abstract

We report on measurements of the Kβ diagram, valence-to-core (VtC), and hypersatellite X-ray spectra induced in metallic Cr by photon single and double K-shell ionization. The experiment was carried out at the Stanford Synchrotron Radiation Lightsource using the seven-crystal Johann-type hard X-ray spectrometer of the beamline 6-2. For the Kβ diagram and VtC transitions, the present study confirms the line shape features observed in previous works, whereas the K h β hypersatellite transition was found to exhibit a complex spectral line shape and a characteristic low-energy shoulder. The energy shift of the hypersatellite relative to the parent diagram line was deduced from the measurements and compared with the result of extensive multiconfiguration Dirac–Fock (MCDF) calculations. A very good agreement between experiment and theory was found. The MCDF calculations were also used to compute the theoretical line shape of the hypersatellite. A satisfactory agreement was obtained between the overall shapes of the experimental and theoretical spectra, but deviations were observed on the low- and high-energy flanks of the hypersatellite line. The discrepancies were explained by chemical effects, which were not considered in the MCDF calculations performed for isolated atoms.

Ménesguen, Y., {M. C. } Lépy, Y. Ito, M. Yamashita, S. Fukushima, M. Polasik, K. Słabkowska, Syrocki, E. Wȩder, P. Indelicato, {J. P. } Marques, {J. M. } Sampaio, M. Guerra, F. Parente, and {J. P. } Santos. "Precise x-ray energies of gadolinium determined by a combined experimental and theoretical approach." Journal Of Quantitative Spectroscopy & Radiative Transfer 236 (2019). Abstract

We combined different experimental techniques with a theoretical approach to determine a consistent set of diagram lines energies and binding energies. We propose an original approach consisting in determining the mass attenuation coefficients in an energy range covering the L-, M- and N- absorption edges, including a detailed evaluation of the associated uncertainties, to derive precisely the binding energies. We investigated the Lα, Lβ and M spectra of Gd with an independantly calibrated high-resolution anti-parallel double-crystal x-ray spectrometer. All the lines were identified and found in excellent agreement with the binding energies previously derived. Morever, we identified for the first time M5−O2, M4−O2,3 and M4−N2,3 diagram lines.

Santos, J. P., Chintan Shah, José Crespo R. López-Urrutia, Ming Feng Gu, Thomas Pfeifer, José Marques, Filipe Grilo, José Paulo Santos, and Pedro Amaro. "Revisiting the Fe xvii Line Emission Problem: Laboratory Measurements of the 3s–2p and 3d–2p Line-formation Channels." The Astrophysical Journal (2019). AbstractWebsite