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8 pags., 5 figs., 2 tabs. ; We present experimental total cross sections for electron scattering from furfural in the energy range from 10 to 1000 eV, as measured using a double electrostatic analyzer gas cell electron transmission experiment. These results are compared to theoretical data for furfural, as well as to experimental and theoretical values for the structurally similar molecules furan and tetrahydrofuran. The measured total cross section is in agreement with the theoretical results obtained by means of the independent-atom model with screening corrected additivity rule including interference method. In the region of higher electron energies, from 500 eV to 10 keV, the total electron scattering cross section is also estimated using a semi-empirical model based on the number of electrons and dipole polarizabilities of the molecular targets. Together with the recently measured differential and integral cross sections, and the furfural energy-loss spectra, the present total cross section data nearly complete the data set that is required for numerical simulation of low-energy electron processes in furfural, covering the range of projectile energies from a few electron volts up to 10 keV. ; We acknowledge the financial support received from the European Union Seventh Framework Programme (PEOPLE-2013-ITN-ARGENT Marie Curie project), under Grant Agreement No. 608163, and from the Spanish Ministerio de Economia y Competitividad (Project No. FIS2016-80440). M.J.B. also acknowledges the Australian Research Council for some financial support. ; 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

This work is partially supported by the Spanish Ministerio de Economia 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 Autonoma de Madrid local government. This work was also supported by the EPSRC and the Australian Research Council through its Centres of Excellence programme. We acknowledge Professor Carl Winstead for providing us with numerical values of their data presented in this paper. D. A. and F. F. S. acknowledge the Portuguese Foundation for Science and Technology (FCT-MEC) for a post-graduate SFRH/BD/61645/2009 and post-doctoral SFRH/BPD/68979/2010 grants. We are also grateful to the partial funding from the Portuguese research Grant Nos. PEst-OE/FIS/UI0068/2011 and PTDC/FIS-ATO/1832/2012 through FCT-MEC. P. L.-V. acknowledges his visiting Professor position at The Open University, UK. ; 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. (C) 2013 AIP Publishing LLC. ; publishersversion ; published

7 pags., 3 figs., 4 tabs. ; We present a range of cross section measurements for the low-energy scattering of positrons from pyridine, for incident positron energies of less than 20 eV, as well as the independent atom model with the screening corrected additivity rule including interference effects calculation, of positron scattering from pyridine, with dipole rotational excitations accounted for using the Born approximation. Comparisons are made between the experimental measurements and theoretical calculations. For the positronium formation cross section, we also compare with results from a recent empirical model. In general, quite good agreement is seen between the calculations and measurements although some discrepancies remain which may require further investigation. It is hoped that the present study will stimulate development of ab initio level theoretical methods to be applied to this important scattering system. ; The authors would like to acknowledge the Australian Research Council (ARC) Discovery Programmes for funding support (No. DP140102854) and Ross Tranter for technical support for the experimental apparatus. L.E.G., F.B., and G.G. also acknowledge partial financial support from the Spanish Ministry MINECO (No. FIS2016- 80440) and the European Union ITN-Marie Curie programme (No. ARGENT-608163). ; Peer Reviewed

12 pags., 6 figs., 4 tabs. ; We report on theoretical elastic and experimental vibrational-excitation differential cross sections (DCSs) for electron scattering from para-benzoquinone (C6H4O2), in the intermediate energy range 15–50 eV. The calculations were conducted with two different theoretical methodologies, the Schwinger multichannel method with pseudopotentials (SMCPP) and the independent atom method with screening corrected additivity rule (IAM-SCAR) that also nowincorporates a further interference (I) term. The SMCPP with N energetically open electronic states (Nopen) at the static-exchange-pluspolarisation (Nopench-SEP) level was used to calculate the scattering amplitudes using a channel coupling scheme that ranges from 1ch-SE up to the 89ch-SEP level of approximation.We found that in going from the 38ch-SEP to the 89ch-SEP, at all energies considered here, the elastic DCSs did not change significantly in terms of both their shapes and magnitudes. This is a good indication that our SMCPP 89ch-SEP elastic DCSs are converged with respect to the multichannel coupling effect for the investigated intermediate energies. While agreement between our IAM-SCAR+I and SMCPP 89ch- SEP computations improves as the incident electron energy increases from 15 eV, overall the level of accord is only marginal. This is particularly true at middle scattering angles, suggesting that our SCAR and interference corrections are failing somewhat for this molecule below50 eV.We also report experimental DCS results, using a crossed-beam apparatus, for excitation of some of the unresolved ("hybrid") vibrational quanta (bands I–III) of para-benzoquinone. Those data were derived from electron energy loss spectra that were measured over a scattered electron angular range of 10–90 and put on an absolute scale using our elastic SMCPP 89ch-SEP DCS results. The energy resolution of our measurements was s80 meV, which is why, at least in part, the observed vibrational features were only partially resolved. To the best of our knowledge, there are no other experimental or theoretical vibrational excitation results against which we might compare the present measurements. ; This study has been partially supported by the Spanish Ministry MINECO (Project No. FIS2016-80440), COST (CM301 Action) and ITN-Marie Curie (No. ARGENT-608163) European Union programmes. M.A.P.L., M.T.do.N.V. (Grant No. 305672/2014-2), R.F.C., and M.H.F.B. all acknowledge financial support from CNPq, while F.K. (Grant No. 2015/23792-5) and M.T.do.N.V. (Grant No. 2014/10012-9) also thank FAPESP for financial support. Finally, M.J.B. (No. DP160102787) and R.D.W. acknowledge the Australian Research Council for funding. ; Peer Reviewed

8 pags., 3 figs., 4 tabs. ; We report absolute experimental integral cross sections (ICSs) for the electron impact excitation of 6 bands (Bands 0-V) of unresolved electronic-states in para-benzoquinone, for incident electron energies between 20 and 40 eV. Absolute vibrational-excitation ICSs, for 3 composite vibrational bands (Bands I-III), are also reported in that same energy range. In addition, ICSs calculated within our independent atom model (IAM) with screening corrected additivity rule (SCAR) formalism, extended to account for interference (I) terms that arise due to the multi-centre nature of the scattering problem, are also reported. The sum of those ICSs gives the IAM-SCAR+I total cross section (TCS) for electron-para-benzoquinone scattering. Where possible, those calculated IAM-SCAR+I ICSs are compared against corresponding results from the present measurements with an acceptable level of accord being obtained. Similarly, we also present results from our Schwinger multichannel method with pseudopotential (SMCPP) calculations. Here elastic ICSs and ICSs corresponding to the Bands 0-III of unresolved electronic-states are presented, with agreement between the SMCPP electronic-state ICSs and those from our measurements being in good qualitative accord. The energy range of our SMCPP computations is 16-50 eV. Using the binary-encounter-Bethe (BEB) approach, total ionization cross sections for this collision system were computed. Those total ionization cross sections were then added to our SMCPP ICS results, to derive SMCPP/BEB TCSs that are typically in very good accord with those from our IAM-SCAR+I approach. ; This study 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 (No. CM301), and the ITN-Marie Curie (No. ARGENT-608163) European Union programme. M.A.P.L., M.T.do.N.V. (Grant I.D. No. 305672/2014-2), R.F.da.C., and M.H.F.B. all thank CNPq for financial support, while F.K. (Grant I.D. No. 2015/23792-5) also thanks FAPESP for financial support. Finally, M.H.F.B. acknowledges computational support from Professor Carlos de Carvalho at LFTC-DFis-UFPR and at LCPAD-UFPR and from CENAPAD-SP.

14 págs.; 15 figs. ; We report on integral-, momentum transfer- and differential cross sections for elastic and electronically inelastic electron collisions with furfural (CHO). The calculations were performed with two different theoretical methodologies, the Schwinger multichannel method with pseudopotentials (SMCPP) and the independent atom method with screening corrected additivity rule (IAM-SCAR) that now incorporates a further interference (I) term. The SMCPP with N energetically open electronic states (N) at either the static-exchange (N ch-SE) or the static-exchange-plus-polarisation (N ch-SEP) approximation was employed to calculate the scattering amplitudes at impact energies lying between 5 eV and 50 eV, using a channel coupling scheme that ranges from the 1ch-SEP up to the 63ch-SE level of approximation depending on the energy considered. For elastic scattering, we found very good overall agreement at higher energies among our SMCPP cross sections, our IAM-SCAR+I cross sections and the experimental data for furan (a molecule that differs from furfural only by the substitution of a hydrogen atom in furan with an aldehyde functional group). This is a good indication that our elastic cross sections are converged with respect to the multichannel coupling effect for most of the investigated intermediate energies. However, although the present application represents the most sophisticated calculation performed with the SMCPP method thus far, the inelastic cross sections, even for the low lying energy states, are still not completely converged for intermediate and higher energies. We discuss possible reasons leading to this discrepancy and point out what further steps need to be undertaken in order to improve the agreement between the calculated and measured cross sections. ©2016 AIP Publishing LLC ; R.F.d.C., M.C.A.L., M.H.F.B., M.T.d.N.V., and M.A.P.L. acknowledge support from the Brazilian agency Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq). M.T.d.N.V. acknowledges support from Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP). D.B.J. thanks the Australian Research Council (ARC) for financial support provided through a Discovery Early Career Researcher Award. M.J.B. thanks the ARC for some financial support and also thanks CNPq for his "Special Visiting Professor" award at the Federal University of Juiz de Fora. G.G. thanks the Spanish Ministerio de Economia y Competitividad under Project No. FIS2012- 31230 and the European Union COST Action No. CM1301 for funding. ; Peer Reviewed

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

8 págs.; 4 figs.; 4 tabs. ; We report cross sections for electron-impact excitation of vibrational quanta in furfural, at intermediate incident electron energies (20, 30, and 40 eV). The present differential cross sections are measured over the scattered electron angular range 10°-90°, with corresponding integral cross sections subsequently being determined. Furfural is a viable plant-derived alternative to petrochemicals, being produced via low-temperature plasma treatment of biomass. Current yields, however, need to be significantly improved, possibly through modelling, with the present cross sections being an important component of such simulations. To the best of our knowledge, there are no other cross sections for vibrational excitation of furfural available in the literature, so the present data are valuable for this important molecule. C 2015 AIP Publishing LLC ; This work was supported by the Australian, Brazilian, and Spanish government funding agencies (ARC, CNPq, CAPES). D.B.J. thanks the ARC for a Discovery Early Career Researcher Award. R.F.C.N. acknowledges CNPq and Flinders University for financial asistance, while M.J.B. thanks CNPq for his "Special Visiting Professor" award. R.F.C., M.T.N.V., and M.A.P.L. acknowledge financial support from FAPESP, while R.F.C., M.T.N.V., M.H.F.B., M.C.A.L., and M.A.P.L. acknowledge financial support from CNPq. M.C.A.L. also acknowledges support from FAPEMIG. G.G. thanks the Spanish Ministerio de Economía y Competitividad under Project No. FIS2012-31230 and the European Union COST Action CM1301 for funding. ; 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.

20 pags., 7 figs., 6 tabs. ; We report, over an extended energy range, recommended angle-integrated cross sections for elastic scattering, discrete inelastic scattering processes, and the total ionization cross section for electron scattering from atomic indium. In addition, from those angle-integrated cross sections, a grand total cross section is subsequently derived. To construct those recommended cross-section databases, results from original B-spline R-matrix, relativistic convergent close-coupling, and relativistic optical-potential computations are also presented here. Electron transport coefficients are subsequently calculated, using our recommended database, for reduced electric fields ranging from 0.01 Td to 10 000 Td using a multiterm solution of Boltzmann's equation. To facilitate those simulations, a recommended elastic momentum transfer cross-section set is also constructed and presented here. ; The work of K.R.H., O.Z., and K.B. was supported by the United States National Science Foundation under Grant Nos. OAC-1834740 and PHY-1803844 and by the XSEDE supercomputer Allocation No. PHY-090031. The (D)BSR calculations were carried out on Stampede2 at the Texas Advanced Computing Center. The work of D.V.F. and I.B. was supported by the Australian Research Council and resources provided by the Pawsey Supercomputing Centre with funding from the Australian Government and the Government of Western Australia. F.B. and G.G. acknowledge partial financial support from the Spanish Ministry MICIU (Project Nos. FIS2016- 80440 and PID2019-104727-RB-C21) and CSIC (Project No. LINKA20085). This work was also financially supported, in part, by the Australian Research Council (Project No. DP180101655), the Ministry of Education, Science and Technological Development of the Republic of Serbia, and the Institute of Physics (Belgrade). ; Peer reviewed

11 págs.; 6 figs.; 5 tabs. ; © 2015 AIP Publishing LLC. We report results from a joint theoretical and experimental investigation into electron scattering from the important organic species phenol (C6H5OH). Specifically, differential cross sections (DCSs) have been measured and calculated for the electron-impact excitation of the electronic states of C6H5OH. The measurements were carried out at energies in the range 15-40 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-potentials calculations, 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 conducted at the static exchange plus polarisation (SEP)-level using a minimum orbital basis for single configuration interaction (MOBSCI) approach. Agreement between the measured and calculated DCSs was typically fair, although to obtain quantitative accord, the theory would need to incorporate even more channels into the MOBSCI. ; This research was supported by the Australian and Brazilian Governmental Funding Agencies (ARC, CNPq and CAPES). D.B.J. thanks the ARC for a Discovery Early Career Researcher Award. R.F.C.N. acknowledges CNPq and Flinders University for financial assistance, while H.V.D. acknowledges CAPES and Flinders. M.J.B. thanks CNPq for his "Special Visiting Professor" award. E.M.O., R.F.C., M.T.N.V., and M.A.P.L. acknowledge financial support from FAPESP, while R.F.C., M.T.N.V., M.H.F.B., M.C.A.L., and M.A.P.L. acknowledge financial support from CNPq. K.L.N. thanks CNPq for an "Attracting Young Talent Grant" under the "Science Without Borders" program. G.G. acknowledges financial support from MINECO (FIS2012-31230) and COST (MP1002, CM1301). ; Peer Reviewed