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8 págs.; 7 figs.; 2 tabs. ; © 2015 AIP Publishing LLC. Water is often used as the medium for characterizing the effects of radiation on living tissue. However, in this study, charged-particle track simulations are employed to quantify the induced physicochemical and potential biological implications when a primary ionising particle with energy 10 keV strikes a medium made up entirely of water or pyrimidine. Note that pyrimidine was chosen as the DNA/RNA bases cytosine, thymine, and uracil can be considered pyrimidine derivatives. This study aims to assess the influence of the choice of medium on the charged-particle transport, and identify how appropriate it is to use water as the default medium to describe the effects of ionising radiation on living tissue. Based on the respective electron interaction cross sections, we provide a model, which allows the study of radiation effects not only in terms of energy deposition (absorbed dose and stopping power) but also in terms of the number of induced molecular processes. Results of these parameters for water and pyrimidine are presented and compared. ; This research was supported by the Australian Research Council (ARC) through its Centres of Excellence Program. D.B.J. thanks the ARC for provision of a Discovery Early Career Researcher Award. We also acknowledge the support of the Spanish Ministerio de Economia y Competitivad under Project No. FIS 2012-31230 and the European Union COST Actions (MP1002 and CM1301). P.L.V. acknowledges the Portuguese Foundation for Science and Technology (FCTMEC) through research grants PTDC/FIS-ATO/1832/2012, UID/FIS/00068/2013, and SFRH/BSAB/105792/2014. P.L.V. also acknowledges his Visiting Professor position at Flinders University, Adelaide, South Australia. ; Peer Reviewed

6 pags., 5 figs., 1 tab. ; We report on experimental total electron scattering cross-section (TCS) from pyridine (CHN) for incident electron energies between 10 and 1000 eV, with experimental uncertainties within 5–10%, as measured with a double electrostatic analyser apparatus. The experimental results are compared with our theoretical calculations performed within the independent atom model complemented with a screening corrected additivity rule (IAM-SCAR) procedure which has been updated by including interference effects. A good level of agreement is found between both data sources within the experimental uncertainties. The present TCS results for electron impact energy under study contribute, together with other scattering data available in the literature, to achieve a consistent set of cross section data for modelling purposes. ; We acknowledge the financial support received from theSpanish Ministerio de Economia y Competitividad (Project FIS2016-80440), the European Union Seventh Frame-workProgramme (PEOPLE-2013-ITN-ARGENT Marie Curie project)under grant agreement no. 608163 and the European Union COSTAction CM1301 (CELINA). FFS acknowledges the Portuguese National Funding Agency FCT-MCTES through researcher positionIF-FCT IF/00380/2014 and together with PLV the research grantUID/FIS/00068/2013. This work was also supported by RadiationBiology and Biophysics Doctoral Training Programme (RaBBiT,PD/00193/2010); UID/Multi/ 04378/2013 (UCIBIO)

7 págs.; 3 figs.; 1 tab. ; We report elastic differential cross sections (DCSs) for electron interactions with acetone, C3H6O. The incident electron energy range was 7.0-50 eV, and the scattered electron angular range for the differential measurements varied from 10° to 120°. The calculated cross sections were obtained with two different methodologies, the Schwinger multichannel method with pseudopotentials (SMCPP), and the independent-atom method with screening-corrected additivity rule (IAM-SCAR). The present elastic DCSs have been found to agree well with the results of IAM-SCAR calculations above 20 eV, and also with the SMC calculations below 30 eV. Although some discrepancies were found for lower energies, the agreement between the SMCPP data and the DCSs obtained with the IAM-SCAR method improves, as expected, as the impact energy increases. Comparison with previous DCSs shows good agreement albeit the present data is extended down to lower electron impact energies. We find a low-lying π∗ shape resonance located at 2.6 eV, in agreement with recent results on electron collisions with acetone [M. G. P. Homem et al., Phys. Rev. A 92, 032711 (2015)10.1103/PhysRevA.92.032711]. The presence of a σ∗ resonance is also discussed. ©2016 American Physical Society ; Acknowledge the Brazilian Agency Coordenacao de Aperfeicoamento de Pessoal de Nıvel Superior (CAPES), under CAPES/FCT Programme (Process No. 23038.002465/2014-87).E.L. acknowledges the Brazilian Agency Conselho Nacional de Desenvolvimento Cientıfico e Tecnologico (CNPq) and the Science Without Borders Programme for opportunities to study abroad. M.H.F.B. also acknowledges support from CNPq. F.F.S. acknowledges the Portuguese National Funding Agency FCT through Researcher Contract No. IF-FCT IF/00380/2014, and, together with P.L.V., Research GrantsNo. PTDC/FIS-ATO/1832/2012 and No. UID/FIS/00068/2013. This work has been partially supported by the Spanish MINECO(Project No. FIS2012-31230).We also acknowledge financial support from European Union programs (COST CM1301 and FP7-ITN ARGENT). This work was also supported by FCT-MCTES, Radiation Biology and Biophysics Doctoral Training Programme (RaBBiT, PD/00193/2012); UID/Multi/04378/2013 (UCIBIO). ; Peer Reviewed

Sem PDF. This research was supported by the Australian Research Council (ARC) through its Centres of Excellence Program. D.B.J. thanks the ARC for provision of a Discovery Early Career Researcher Award. We also acknowledge the support of the Spanish Ministerio de Economia y Competitivad under Project No. FIS 2012-31230 and the European Union COST Actions (MP1002 and CM1301). P.L.V. acknowledges the Portuguese Foundation for Science and Technology (FCT-MEC) through research grants PTDC/FIS-ATO/1832/2012, UID/FIS/00068/2013, and SFRH/BSAB/105792/2014. P.L.V. also acknowledges his Visiting Professor position at Flinders University, Adelaide, South Australia. ; Water is often used as the medium for characterizing the effects of radiation on living tissue. However, in this study, charged-particle track simulations are employed to quantify the induced physicochemical and potential biological implications when a primary ionising particle with energy 10 keV strikes a medium made up entirely of water or pyrimidine. Note that pyrimidine was chosen as the DNA/RNA bases cytosine, thymine, and uracil can be considered pyrimidine derivatives. This study aims to assess the influence of the choice of medium on the charged-particle transport, and identify how appropriate it is to use water as the default medium to describe the effects of ionising radiation on living tissue. Based on the respective electron interaction cross sections, we provide a model, which allows the study of radiation effects not only in terms of energy deposition (absorbed dose and stopping power) but also in terms of the number of induced molecular processes. Results of these parameters for water and pyrimidine are presented and compared. ; publishersversion ; published

Total electron scattering cross sections for pyrazine in the energy range 10-500 eV have been measured with a new magnetically confined electron transmission-beam apparatus. Theoretical differential and integral elastic, as well as integral inelastic, cross sections have been calculated by means of a screening-corrected form of the independent-atom representation (IAM-SCAR) from 10 to 1000 eV incident electron energies. The present experimental and theoretical total cross sections show a good level of agreement, to within 10%, in the overlapping energy range. Consistency of these results with previous calculations (i.e., the R-matrix and Schwinger Multichannel methods) and elastic scattering measurements at lower energies, below 10 eV, is also discussed. © 2013 AIP Publishing LLC. ; This work is partially supported by the Spanish Ministerio de Economía y Competitividad (Projects FIS2009-10245 and FIS2012-31320) and the EU/ESF COST Action MP1002 "Nanoscale Insights into Ion Beam Cancer Therapy (Nano-IBCT)". M.C.F. is financially supported by the Comunidad Autónoma de Madrid local government. ; Peer Reviewed

16 pags., 13 figs., 2 tabs. ; Abstract: A self-consistent data set, with all the necessary inputs for Monte Carlo simulations of electron transport through gaseous tetrahydrofuran (THF) in the energy range 1–100 eV, has been critically compiled in this study. Accurate measurements of total electron scattering cross sections (TCSs) from THF have been obtained, and considered as reference values to validate the self-consistency of the proposed data set. Monte Carlo simulations of the magnetically confined electron transport through a gas cell containing THF for different beam energies (3, 10 and 70 eV) and pressures (2.5 and 5.0 mTorr) have also been performed by using a novel code developed in Madrid. In order to probe the accuracy of the proposed data set, the simulated results have been compared with the corresponding experimental data, the latter obtained with the same experimental configuration where the TCSs have been measured. Graphic Abstract: [Figure not available: see fulltext.] ; This study has been partially supported by the Spanish Ministerio de Ciencia e Innovacion (Project PID2019-104727RB-C21) and CSIC (Project LINKA20085). Some financial support from the Australian Research Council (DP180101655) is also acknowledged. AGA and LA thank MICIU and the local CAM government, respectively, for their corresponding grants within the "Garant´ıa Juvenil" programmes. AIL and PLV acknowledge the the Portuguese National Funding Agency (FCT) through research Grants CEFITEC (UIDB/00068/2020) and PTDC/FIS-AQM/31281/2017. JdeU acknowledges the support of Project PAPIIT-UNAM IN118520.

13 págs.; 8 figs.; 6 tabs. ; We report results from a joint experimental and theoretical investigation into electron scattering from the important industrial species furfural (CHO). Specifically, differential cross sections (DCSs) have been measured and calculated for the electron-impact excitation of the electronic states of CHO. The measurements were carried out at energies in the range 20-40 eV, and for scattered-electron angles between 10°and 90°. The energy resolution of those experiments was typically ∼80 meV. Corresponding Schwinger multichannel method with pseudo-potential calculations, for energies between 6-50 eV and with and without Born-closure, were also performed for a sub-set of the excited electronic-states that were accessed in the measurements. Those calculations were undertaken at the static exchange plus polarisation-level using a minimum orbital basis for single configuration interaction (MOB-SCI) approach. Agreement between the measured and calculated DCSs was qualitatively quite good, although to obtain quantitative accord, the theory would need to incorporate even more channels into the MOB-SCI. The role of multichannel coupling on the computed electronic-state DCSs is also explored in some detail. ©2016 AIP Publishing LLC ; R.F.C.N. thanks CNPq (Brazil) and the Science Without Borders Programme for opportunities to study abroad. D.B.J. thanks the Australian Research Council (ARC) for financial support provided through a Discovery Early Career Research Award, while M.J.B. also thanks the ARC for their support. M.J.B. and M.C.A.L. acknowledge the Brazilian agencies CNPq and FAPEMIG. P.L.-V. acknowledges the Portuguese Foundation for Science and Technology (FCTMEC) through Grant Nos. PTDC/FIS-ATO/1832/2012 and UIO/FIS/00068/2013. G.G. acknowledges partial financial support from the Spanish Ministry MINECO (Project No. FIS2012-31230) and the European Union COST Action No. CM1301 (CELINA). Finally, R.F.d.C., M.T.d.N.V., M.H.F.B., and M.A.P.L. acknowledge support from the Brazilian agency CNPq and M.T.d.N.V. also thanks FAPESP. ; Peer Reviewed

R.F.C.N. thanks CNPq (Brazil) and the Science Without Borders Programme for opportunities to study abroad. D.B.J. thanks the Australian Research Council (ARC) for financial support provided through a Discovery Early Career Research Award, while M.J.B. also thanks the ARC for their support. M.J.B. and M.C.A.L. acknowledge the Brazilian agencies CNPq and FAPEMIG. P.L.-V. acknowledges the Portuguese Foundation for Science and Technology (FCT-MEC) through Grant Nos. PTDC/FIS-ATO/1832/2012 and UIO/FIS/00068/2013. G.G. acknowledges partial financial support from the Spanish Ministry MINECO (Project No. FIS2012-31230) and the European Union COST Action No. CM1301 (CELINA). Finally, R.F.d.C., M.T.d.N.V., M.H.F.B., and M.A.P.L. acknowledge support from the Brazilian agency CNPq and M.T.d.N.V. also thanks FAPESP. ; We report results from a joint experimental and theoretical investigation into electron scattering from the important industrial species furfural (C5H4O2). Specifically, differential cross sections (DCSs) have been measured and calculated for the electron-impact excitation of the electronic states of C5H4O2. The measurements were carried out at energies in the range 20-40 eV, and for scattered-electron angles between 10°and 90°. The energy resolution of those experiments was typically ∼80 meV. Corresponding Schwinger multichannel method with pseudo-potential calculations, for energies between 6-50 eV and with and without Born-closure, were also performed for a sub-set of the excited electronic-states that were accessed in the measurements. Those calculations were undertaken at the static exchange plus polarisation-level using a minimum orbital basis for single configuration interaction (MOB-SCI) approach. Agreement between the measured and calculated DCSs was qualitatively quite good, although to obtain quantitative accord, the theory would need to incorporate even more channels into the MOB-SCI. The role of multichannel coupling on the computed electronic-state DCSs is also explored in some detail. ; publishersversion ; published

10 pags., 7 figs., 7 tabs. ; Angle resolved electron energy loss spectra (EELS) for para-benzoquinone (CHO) have been recorded for incident electron energies of 20, 30, and 40 eV. Measured differential cross sections (DCSs) for electronic band features, composed of a combination of energetically unresolved electronic states, are subsequently derived from those EELS. Where possible, the obtained DCSs are compared with those calculated using the Schwinger multichannel method with pseudopotentials. These calculations were performed using a minimum orbital basis single configuration interaction framework at the static exchange plus polarisation level. Here, quite reasonable agreement between the experimental cross sections and the theoretical cross sections for the summation of unresolved states was observed. ; This work was partially supported by the Australian Research Council (ARC) through Grant No. DP160120787. It was also partially supported by the Spanish Ministry MINECO (Project No. FIS2016-80440), the COST Action (CM301), and ITN-Marie Curie (ARGENT-608163) European Union programmes. M.A.P.L., M.T.d.N.V. (Grant I.D. 305672/2014- 2), R.F.d.C., and M.H.F.B. all acknowledge financial support from CNPq, while F.K.(Grant I.D. 2015/23792-5) also thank FAPESP for financial support. F.F.d.S. acknowledges the Portuguese National Funding Agency FCT-MCTES through a researcher position IF-FCT IF/00380/2014 and together with P.L.-V. the research Grant No. UID/FIS/00068/2013.