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Guerra, M., F. Parente, and J. P. Santos. "Electron impact ionization of atomic target inner-shells." Journal of Physics: Conference Series 194 (2009): 042047. AbstractWebsite

There is a need for reliable theoretical methods to calculate electron-impact total ionization cross sections for the large number of neutral atoms and ions with open shell structures. These cross sections are used in a wide range of scientific and industrial applications, such as astrophysical plasmas, atmospheric science, X-ray lasers, magnetic fusion, radiation physics, semiconductor fabrication, accelerator physics and tumor therapy physics. The binary-encounter-Bethe (BEB) model [1], using an analytic formula that requires only two atomic constants, the binding energy and kinetic energy of the electrons, generates direct ionization cross sections for any neutral atom (or molecule), which are reliable in intensity (15%) and shape from the ionization threshold to a few keV in the incident energy [3], or to thousands keV if we consider its relativistic version(RBEB) [2]. In this work we present K- and L-shell ionization cross sections calculations for heavy atoms.

Guerra, M., F. Parente, and J. P. Santos. "Electron impact ionization cross sections of several ionization stages of Kr, Ar and Fe." International Journal of Mass Spectrometry 348 (2013): 1-8. AbstractWebsite

International Journal of Mass Spectrometry, 348 (2013) 1-8. doi:10.1016/j.ijms.2013.02.011

Guerra, M., F. Parente, P. Indelicato, and J. P. Santos. "Modified binary encounter Bethe model for electron-impact ionization." International Journal of Mass Spectrometry Accepted (2011). Abstract

Theoretical expressions for ionization cross sections by electron impact based on the binary encounter Bethe (BEB) model, valid from ionization threshold up to relativistic energies, are proposed.The new modified BEB (MBEB) and its relativistic counterpart (MRBEB) expressions are simpler than the BEB (nonrelativistic and relativistic) expressions because they require only one atomic parameter, namely the binding energy of the electrons to be ionized, and use only one scaling term for the ionization of all sub-shells.The new models are used to calculate the K-, L- and M-shell ionization cross sections by electron impact for several atoms with Z from 6 to 83.Comparisons with all, to the best of our knowledge, available experimental data show that this model is as good or better than other models, with less complexity.

Guerra, M., S. C. Pé-Leve Santos, A. M. E. Barroso, C. P. S. Fonseca, M. Eloy Cruz, P. Amaro, J. L. Figueirinhas, M. L. Carvalho, and J. P. Santos. "Spatially resolved determination of toxic trace elements in plants of Panasqueira mining region using micro X-ray fluorescence." Microscopy and Microanalysis 21 (2015): 54-55. AbstractWebsite
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Guerra, M., P. Amaro, J. P. Santos, and P. Indelicato. "Relativistic calculations of screening parameters and atomic radii of neutral atoms." Atomic Data and Nuclear Data Tables 117-118 (2017): 439-457. AbstractWebsite

Atomic Data and Nuclear Data Tables, 117-118 (2017) 439-457. doi:10.1016/j.adt.2017.01.001

Guerra, M., R. M. Pinto, J. P. Santos, and A. C. S. Paiva. "Towards the assignment of the REMPI spectrum of Ph 2O using CIS and TD-DFT methods." Molecular Physics 111 (2013): 3311-3319. AbstractWebsite
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Guerra, M., P. Amaro, J. Machado, and J. P. Santos. "Single differential electron impact ionization cross sections in the binary-encounter- Bethe approximation for the low binding energy regime." Journal of Physics B: Atomic, Molecular and Optical Physics 48 (2015): 1-9. AbstractWebsite

Journal of Physics B: Atomic, Molecular and Optical Physics, 48(2015) 185202. doi:10.1088/0953-4075/48/18/185202

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
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