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This document discusses the importance of atomic, molecular, and optical (AMO) physics in various scientific and applied fields. AMO physics has contributed to technological advancements such as lasers, spectroscopy, and quantum optics, which have had significant impacts on fields like medical imaging and communication systems. It also plays a vital role in quantum information science and the development of new materials. The document highlights specific articles in a special issue that explore the impact of photon and particle interactions with AMO systems, covering topics such as proton impact fragmentation, electron-impact studies, photon interactions with sodium atoms, and plasma-field-induced structures. The document concludes by discussing future research prospects in AMO science, including ultrafast spectroscopy, quantum information science, ultracold quantum gases, and the integration of superconducting circuits with AMO systems. [Extracted from the article]

Although the comparison of fully differential ionization data for particle and antiparticle impact provides the ultimate tests of theoretical models, only very low antiparticle beam intensities are available. Hence, few experiments of this type have been performed. Therefore, available experimentally obtained single and double differential cross-sections, which are much easier to obtain, are compared in order to demonstrate differences when only the projectile mass or charge (+1 or −1) is changed. Included in the comparison are cross-sections calculated for positron and electron impact using a three-particle classical trajectory Monte Carlo method. The calculated cross-sections provide independent information about the ejected electron and the scattered projectile contributions, plus information about the impact parameters, all as functions of the collision kinematics. From these comparisons, suggestions as to where future investigations are both feasible and useful are provided. [ABSTRACT FROM AUTHOR]

Electron removal (target ionization and/or projectile electron loss) in neutral–atom collisions is theoretically studied for the impact of H 0 , He 0 and He + beams on noble gases (He, Ne and Ar). These reactions are investigated theoretically within the Continuum Distorted Wave-Eikonal Initial State model. New features have been included in the theoretical model: (i) a scaled projectile charge depending on its velocity and charge, (ii) a dynamic projectile-effective-charge depending on the momentum transfer, and (iii) a dynamic target-effective-charge depending on the kinematics of the emitted electron. The energy and angular spectra of emitted electrons from the target and from the projectile are calculated and compared with the available experimental data. Also, the influence of each one of the corrections on the resulting spectra will be studied. [ABSTRACT FROM AUTHOR]

In situ produced photoelectrons and precipitating solar wind electrons are two distinct hot electron populations in the dayside Martian upper atmosphere. While each population has been known for decades, its relative contribution to the measured hot electron flux has not been adequately characterized up to now. In this study, we implement a two‐stream kinetic model to compute the hot electron flux for a open magnetic field configuration. By comparing model results to realistic data acquired by the Mars Atmosphere and Volatile Evolution mission, we show that the electron fluxes predicted by the pure photoelectron model are enormously underestimated, especially in the direction toward Mars, but the measurements can be adequately reproduced once solar wind electron precipitation is taken into account. Such a precipitation plays a crucial role above 180 km, not only for hot electrons at all energies that move toward Mars but also for electrons above 1,000 eV that move away from Mars due to the backscattering of precipitating electrons. In contrast, the hot electron population is predicted to be mostly composed of photoelectrons below 180 km. The significance of precipitating solar wind electrons is also evaluated, revealing an appreciable impact on the structure of the dayside Martian upper atmosphere at high altitudes, where electron impact ionization is enhanced by a factor of 7 and cold electron heating enhanced by a factor of 4. Plain Language Summary: This study examines two hot electron populations in the dayside Martian upper atmosphere: locally produced photoelectrons and precipitating solar wind electrons. We intend to figure out how much each population contributes to the total hot electron flux. For this purpose, we construct a kinetic model and compare the model results to the realistic data collected by the Mars Atmosphere and Volatile Evolution mission. We find that the measurements are seriously underestimated by the model with pure photoelectrons, but adequately reproduced when both electron populations are included. In particular, solar wind electrons account for all hot electrons moving toward Mars and part of them moving away. Meanwhile, solar wind electrons likely exert an appreciable impact on the structure of the dayside Martian upper atmosphere, enhancing both ionization and cold electron heating. Key Points: A two‐stream kinetic model is employed to provide a preliminary distinction between photoelectrons and solar wind electrons at MarsPhotoelectrons are found to dominate the hot electron population in all directions below 180 km in the dayside Martian ionospherePrecipitating solar wind electrons are vital above 180 km, for all hot electrons moving toward Mars and part of them moving away from Mars [ABSTRACT FROM AUTHOR]

Electron impact scattering from C 3 F 6 O is studied in this work. The R-matrix method was used for the calculations of elastic, momentum transfer, and excitation cross sections. The attachment cross section was obtained through a parametric estimator based on the R-matrix outputs. The Binary-Encounter-Bethe (BEB) method was used for computing the ionization cross section. The obtained cross section set was used for the transport studies using the BOLSIG+ code, which is a two-term Boltzmann equation solver. The present calculation was performed for steady-state Townsend experimental conditions for E/N, covering a range of 100–1000 Td. The critical dielectric strength of pure C 3 F 6 O was found to be 475 Td, which is much greater than that of SF 6 (355 Td). The effect of the addition of different buffer gases, such as CO 2 , N 2 , and O 2 , was also examined. For the C 3 F 6 O–CO 2 , C 3 F 6 O–N 2 , and C 3 F 6 O–O 2 mixtures with 65%, 55%, and 60% C 3 F 6 O, respectively, the critical dielectric strength was determined to be essentially the same as that of pure SF 6 . The presence of synergism was confirmed for these gas mixtures. We further derived the Paschen curve using a fitting method with the transport parameters as the basic inputs. The minimum breakdown voltage of C 3 F 6 O accounted for only 55% of that of SF 6 . The buffer gas mixture improved the condition; however, the performance of CO 2 and O 2 mixtures was not satisfactory. The addition of N 2 as the buffer gas significantly improved the breakdown property of the gas. The mixture of ≥99% of N 2 or ≤1% of C 3 F 6 O gave a better breakdown characteristic than SF 6 . Any proportion ≥90% of N 2 or ≤10% of C 3 F 6 O was suitable in the higher pressure ranges. The present work demonstrates the potential of C 3 F 6 O as a substitute gas for SF 6 with a negligible environmental threat. [ABSTRACT FROM AUTHOR]

In extreme ultraviolet (EUV) lithography, tin droplets evaporate and subsequently coat various surfaces including the collector mirrors. To clean off the tin, a hydrogen plasma is often used, but as a result, an unstable by-product, stannane (SnH4) is formed. The physicochemical characteristics of this gas, its formation in a plasma process, and its interaction with various materials have not been explored and understood completely. Here, the electron ionization mass spectrum of SnH4 is presented. All ten natural abundance isotopes were observed experimentally for each fragment, i.e., Sn+, SnH+, SnH2+, and SnH3+. Density functional electronic structure theory was used to calculate the optimized ground state geometries of these gas phase species and their relative stabilities and helped explain the absence of SnH4+ in the observed signals. The density of the liquid, its cracking pattern, and the surface morphology of its deposits were examined. The surface of the deposited tin film resulting from the decomposition and subsequent oxidation was characterized by x-ray photoelectron spectroscopy. The main species found at the surface were metallic tin and tin (II) oxide (SnO). The detailed characterization of stannane should help correctly identify it in EUV lithographic processes and develop approaches in the future to mitigate its decomposition and redeposition on the collector mirrors or vacuum chamber walls. [ABSTRACT FROM AUTHOR]

We present a comparison of the photoionization dynamics of the 4d shell of XeF2 from threshold to 250 eV to those of the prototypical 4d shell of atomic Xe. The new experimental data include spin–orbit and ligand-field-resolved partial cross sections, photoelectron angular distributions, branching fractions, and lifetime widths for the 4d-hole states. The spin–orbit branching fractions and angular distributions are remarkably similar to the corresponding distributions from atomic Xe across a broad energy interval that includes both the intense shape resonance in the f continuum and a Cooper minimum in the same channel. The angular distributions and branching fractions are also in reasonably good agreement with our first-principles theoretical calculations on XeF2. Data are also presented on the lifetime widths of the substate-resolved 4d-hole states of XeF2. While the trends in the widths are similar to those in the earlier experimental and theoretical work, the linewidths are considerably smaller than in the previous measurements, which may require some reinterpretation of the decay mechanism. Finally, we present new data and an analysis of the Auger electron spectra for ionization above the 4d thresholds and resonant Auger spectra for several pre-edge features. [ABSTRACT FROM AUTHOR]

We present a comparison of the photoionization dynamics of the 4d shell of XeF2 from threshold to 250 eV to those of the prototypical 4d shell of atomic Xe. The new experimental data include spin–orbit and ligand-field-resolved partial cross sections, photoelectron angular distributions, branching fractions, and lifetime widths for the 4d-hole states. The spin–orbit branching fractions and angular distributions are remarkably similar to the corresponding distributions from atomic Xe across a broad energy interval that includes both the intense shape resonance in the f continuum and a Cooper minimum in the same channel. The angular distributions and branching fractions are also in reasonably good agreement with our first-principles theoretical calculations on XeF2. Data are also presented on the lifetime widths of the substate-resolved 4d-hole states of XeF2. While the trends in the widths are similar to those in the earlier experimental and theoretical work, the linewidths are considerably smaller than in the previous measurements, which may require some reinterpretation of the decay mechanism. Finally, we present new data and an analysis of the Auger electron spectra for ionization above the 4d thresholds and resonant Auger spectra for several pre-edge features. [ABSTRACT FROM AUTHOR]

Collisional data for the excitation of NH by H2 are key to accurately derive the NH abundance in astrophysical media. We present a new four-dimensional potential energy surface (PES) for the NH–H2 van der Waals complex. The ab initio calculations of the PES were carried out using the explicitly correlated partially spin-restricted coupled cluster method with single, double, and perturbative triple excitations [RCCSD(T)-F12a] with the augmented correlation-consistent polarized valence triple zeta basis set. The PES was represented by an angular expansion in terms of coupled spherical harmonics. The global minimum corresponds to the linear structure with a well depth De = 149.10 cm−1. The calculated dissociation energy D0 is found to be 30.55 and 22.11 cm−1 for ortho-H2 and para-H2 complexes, respectively. These results are in agreement with the experimental values. Then, we perform quantum close-coupling calculations of the fine structure resolved excitation cross sections of NH induced by collisions with ortho-H2 and para-H2 for collisional energies up to 500 cm−1. We find strong differences between collisions induced by ortho-H2 and para-H2. Propensity rules are discussed. The cross sections are larger for fine structure conserving transitions than for fine structure changing ones, as predicted by theory. These new results should help in interpreting NH interstellar spectra and better constrain the abundance of NH in interstellar molecular clouds. [ABSTRACT FROM AUTHOR]

This article, published in the Chemistry of Natural Compounds journal, explores the chemical components and antimicrobial properties of the essential oil derived from Curcuma vitellina, a rare species of Curcuma found in Vietnam. The essential oil was extracted from the rhizomes of C. vitellina and analyzed using gas chromatography-mass spectrometry. The study identified 36 compounds, with 1,8-cineole and β-pinene being the most prevalent. The essential oil exhibited strong antibacterial effects against 11 tested bacteria, with Escherichia coli being the most susceptible, and also inhibited the growth of three Candida strains. This research provides valuable insights into the chemical composition and potential applications of C. vitellina essential oil as a natural antimicrobial agent. [Extracted from the article]

The electron impact ionization of helium droplets doped with ethylene molecules and clusters yields diverse CXHY+ cations embedded in the droplets. The ionization primarily produces C2H2+, C2H3+, C2H4+, and CH2+, whereas larger carbocations are produced upon the reactions of the primary ions with ethylene molecules. The vibrational excitation of the cations leads to the release of bare cations and cations with a few helium atoms attached. The laser excitation spectra of the embedded cations show well resolved vibrational bands with a few wavenumber widths—an order of magnitude less than those previously obtained in solid matrices or molecular beams by tagging techniques. Comparison with the previous studies of free and tagged CH2+, CH3+, C2H2+, C2H3+, and C2H4+ cations shows that the helium matrix typically introduces a shift in the vibrational frequencies of less than about 20 cm−1, enabling direct comparisons with the results of quantum chemical calculations for structure determination. This work demonstrates a facile technique for the production and spectroscopic study of diverse carbocations, which act as important intermediates in gas and condensed phases. [ABSTRACT FROM AUTHOR]

Density functional theory (DFT) and beyond-DFT methods are often used in combination with photoelectron spectroscopy to obtain physical insights into the electronic structure of molecules and solids. The Kohn–Sham eigenvalues are not electron removal energies except for the highest occupied orbital. The eigenvalues of the highest occupied molecular orbitals often underestimate the electron removal or ionization energies due to the self-interaction (SI) errors in approximate density functionals. In this work, we adapt and implement the density-consistent effective potential method of Kohut, Ryabinkin, and Staroverov [J. Chem. Phys. 140, 18A535 (2014)] to obtain SI-corrected local effective potentials from the SI-corrected Fermi–Löwdin orbitals and density in the Fermi–Löwdin orbital self-interaction correction scheme. The implementation is used to obtain the density of states (photoelectron spectra) and HOMO–LUMO gaps for a set of molecules and polyacenes. Good agreement with experimental values is obtained compared to a range of SI uncorrected density functional approximations. [ABSTRACT FROM AUTHOR]

Using both 0D and 1D fluid models, we revisit the formation of the breathing mode in Hall thrusters and show that it is an ionization instability associated with nonlinearity in the electron power absorption. As the plasma density increases, the axial electric field profile changes and the magnitude of the electric field is enhanced in the ionization zone. This causes a nonlinear increase in the power absorbed by electrons and an increase in the electron temperature and ionization rate factor that is able to partially compensate for the decreasing neutral density to keep the ionization rate high. This sets up a positive feedback mechanism where the electric field continues to be enhanced as the plasma density increases and, consequently, the neutral density needs to decrease even further before plasma growth can be halted. At this point, the neutral density is so low that the plasma can no longer be "sustained," and time is needed for neutrals to refill the thruster channel before "reignition" can occur and the process repeated. By treating the breathing mode as an AC excitation, a carefully designed external circuit can be used to counteract the change in the axial electric field by appropriately varying the anode voltage to stabilize the discharge. [ABSTRACT FROM AUTHOR]

A measurement of the magnitude of the electric dipole moment of the electron (eEDM) larger than that predicted by the Standard Model (SM) of particle physics is expected to have a huge impact on the search for physics beyond the SM. Polar diatomic molecules containing heavy elements experience enhanced sensitivity to parity (P) and time-reversal (T)-violating phenomena, such as the eEDM and the scalar–pseudoscalar (S–PS) interaction between the nucleons and the electrons, and are thus promising candidates for measurements. The NL-eEDM collaboration is preparing an experiment to measure the eEDM and S–PS interaction in a slow beam of cold BaF molecules [P. Aggarwal et al., Eur. Phys. J. D 72, 197 (2018)]. Accurate knowledge of the electronic structure parameters, Wd and Ws, connecting the eEDM and the S–PS interaction to the measurable energy shifts is crucial for the interpretation of these measurements. In this work, we use the finite field relativistic coupled cluster approach to calculate the Wd and Ws parameters in the ground state of the BaF molecule. Special attention was paid to providing a reliable theoretical uncertainty estimate based on investigations of the basis set, electron correlation, relativistic effects, and geometry. Our recommended values of the two parameters, including conservative uncertainty estimates, are 3.13 ± 0.12 × 1 0 24 Hz e cm for Wd and 8.29 ± 0.12 kHz for Ws. [ABSTRACT FROM AUTHOR]

Modeling protoplanetary disks and other interstellar media that are not in local thermal equilibrium require the knowledge of rovibrational transition rate coefficients of molecules in collision with helium and hydrogen. We present a computational method based on the numerically exact coupled-channel (CC) method for rotational transitions and a multi-channel distorted-wave Born approximation (MC-DWBA) for vibrational transitions to calculate state-to-state rate coefficients. We apply this method to the astrophysically important case of CO2–He collisions, using newly computed ab initio three-dimensional potential energy surfaces for CO2–He with CO2 distorted along the symmetric and asymmetric stretch (ν1 and ν3) coordinates. It is shown that the MC-DWBA method is almost as accurate as full CC calculations, but more efficient. We also made computations with the more approximate vibrational coupled-channel rotational infinite-order sudden method but found that this method strongly underestimates the vibrationally inelastic collision cross sections and rate coefficients for both CO2 modes considered. [ABSTRACT FROM AUTHOR]

A linearly approximated explicitly correlated coupled-cluster singles and doubles model for the Fock-space coupled-cluster method has been formulated and implemented. An extension of the Fock-space wave operators is introduced in order to treat the short-range correlation effects for excited and doubly electron-attached states. We show that an effective reduction in the number of active virtuals can also be obtained by improving how the short-range correlation is treated. Numerical results to gauge the performance for valence and Rydberg excitation energies, double ionization potentials, and double electron attachment energies of several molecules are obtained. Statistical measures of the errors in excitation energies show that the explicitly correlated results are within 0.1 eV from the complete basis set limit already at the double-ζ level unless the excitation energies are too close to the ionization thresholds. Similar accuracy is seen for the double ionization potentials and double electron attachment energies. [ABSTRACT FROM AUTHOR]

21-cm intensity mapping (IM) has the potential to be a strong and unique probe of cosmology from redshift of order unity to redshift potentially as high as 30. For post-reionization 21-cm observations, the signal is modulated by the thermal and dynamical reaction of gas in the galaxies to the passage of ionization fronts during the epoch of reionization. In this work, we investigate the impact of inhomogeneous reionization on the post-reionization 21-cm power spectrum and the induced shifts of cosmological parameters at redshifts 3.5 ≲ z ≲ 5.5. We make use of hydrodynamics simulations that could resolve small-scale baryonic structure evolution to quantify H  i abundance fluctuation, while seminumerical large box 21cmfast simulations capable of displaying inhomogeneous reionization process are deployed to track the inhomogeneous evolution of reionization bubbles. We discussed the prospects of capturing this effect in two post-reionization 21-cm IM experiments: SKA1-LOW and PUMA. We find the inhomogeneous reionization effect could impact the H  i power spectrum up to tens of per cent level and shift cosmological parameters estimation from sub-per cent to tens per cent in the observation of future post-reionization 21-cm IM experiments such as PUMA, while SKA1-LOW is likely to miss this effect at the redshifts of interest given the considered configuration. In particular, the shift is up to 0.0206 in the spectral index ns and 0.0192 eV in the sum of the neutrino masses ∑ m ν depending on the reionization model and the observational parameters. We discuss strategies to mitigate and separate these biases. [ABSTRACT FROM AUTHOR]

We present a procedure, based on established principles, to accurately determine the ionisation energies of medium-sized to large polyatomic molecules in supersonic beams. The method combines single-photon excitation from the electronic ground state using tunable vacuumultraviolet laser radiation, the delayed pulsed-field ionisation of high Rydberg states with sequences of pulsed electric fields, and the modelling of the lineshapes from calculations of the fieldionisation dynamics of high Rydberg states and of the rotational contours of the photoelectron bands. The method is illustrated by a measurement of the adiabatic ionisation energy of p-diaminobenzene (p-DB), for which we obtain the value of 54,617.47(15) cm-1, which represents a more than 20-fold accuracy improvement over previous determinations. [ABSTRACT FROM AUTHOR]

A study on the influence of pore characteristics on the microdischarge plasma inside pores of catalyst is important for understanding plasma catalysis mechanism. This article focuses on the effect of pore interaction on plasma production in pores including electron density, electron temperature, and total ion density, etc. These parameters are calculated by solving the electron energy density conservation equation, electron convection diffusion equation, heavy species conservation equation and Poisson equation. The numerical simulation results show that the distribution of electron density, electron temperature and electric field in and near a pore is apparently affected by the adjacent pore, namely, the time-averaged electron density, total ion density and ionization rate in a pore increase with the pore spacing in the range of 8–150 μ m because the loss of electrons to the wall due to the adjacent pore decreases with the increasing pore spacing, but there is an opposite law for the time-averaged electron temperature and electric field in a pore; moreover, the pore spacing presents more apparent effect on the plasma generation in a smaller pore and at higher applied voltage, indicating stronger interactions between pores at these conditions. The simulation results show that the pore characteristics of porous catalysts including pore spacing and pore diameter may affect the degradation of pollutants in plasma catalysis processes. The study is important for understanding the plasma catalysis mechanisms, especially the influence mechanism of pore interaction on microdischarge in porous catalysts. [ABSTRACT FROM AUTHOR]

Thermal ionization of methenamine (C6H12N4) on the surface of the NaAux intermetallic compound has been studied. It has been established that the processes of decomposition, desorption and ionization of adsorbed compounds, thermally stimulated on the surface, proceed due to the accumulation of energy at the degrees of freedom of the adsorption complex, including the adsorbed compound and a solid, by the mechanism of monomolecular decomposition reactions. In this case, the decomposition of the adsorption complex is accompanied by the desorption of ions that are not in thermal equilibrium with the solid. The uniformity of the temperature dependences of the ion current and their distribution over two groups allowed us to conclude that ions are desorbed from the surface, which correspond to the decays of individual adsorbed molecules, as well as the decays of dimers formed on the surface. The decay of methenamine molecules during thermal ionization occurs in the same way as their decay in vacuum during electron ionization, which indicates the preservation of the bulk structure of methenamine molecules during adsorption and a significant lifetime of the excited state of compounds on NaAux. [ABSTRACT FROM AUTHOR]

The benzylation of three low molecular weight N,N‐disubstituted ethanolamines related to chemical warfare agents (CWAs) to furnish derivatives with improved gas chromatography‐mass spectrometry (GC‐MS) profiles is described. Due to their low molecular weight and polar nature, N,N‐disubstituted ethanolamines are notoriously difficult to detect by routine GC‐MS analyses during Organisation for the Prohibition of Chemical Weapons (OPCW) proficiency tests (PTs), particularly in scenarios when they are present at low levels (~1–10 ppm) amidst more abundant interferences. Our studies revealed that the optimal derivatization conditions involved the treatment of the ethanolamine with benzyl bromide in the presence of an inorganic base (e.g., Na2CO3) in dichloromethane at 55°C for 2 h. This optimized set of conditions was then successfully applied to the derivatization of N,N‐dimethylethanolamine, N,N‐diethylethanolamine and N,N‐diisopropylethanolamine present separately at 1 and 10 μg/mL concentrations in a glycerol‐rich matrix sample featured in the 48th OPCW PT. The benzylated derivatives of the three ethanolamines possessed retention times long enough to clear the massive glycerol‐containing matrix interferences. The protocol herein is introduced as an alternative method for derivatization of these CWA and pharmaceutically important species and should find broad applicability in laboratories where routine forensic analysis is carried out. [ABSTRACT FROM AUTHOR]

Detection of illicit drugs in the environment, particularly in soils, often suggests the present or past location of a clandestine production center for these substances. Thus, development of efficient methods for the analysis and detection of these chemicals is of paramount importance in the field of chemical forensics. In this work, a method involving the extraction and retrospective confirmation of fentanyl, acetylfentanyl, thiofentanyl, and acetylthiofentanyl using trichloroethoxycarbonylation chemistry in a high clay‐content soil is presented. The soil was spiked separately with each fentanyl at two concentrations (1 and 10 μg/g) and their extraction accomplished using ethyl acetate and aqueous NH4OH (pH ~ 11.4) with extraction recoveries ranging from ~56% to 82% for the high‐concentration (10 μg/g) samples while ranging from ~68% to 83% for the low‐concentration (1 μg/g) samples. After their extraction, residues containing each fentanyl were reacted with 2,2,2‐trichloroethoxycarbonyl chloride (Troc‐Cl) to generate two unique and predictable products from each opioid that can be used to retrospectively confirm their presence and identity using EI‐GC‐MS. The method's limit of detection (MDL/LOD) for Troc‐norfentanyl and Troc‐noracetylfentanyl were estimated to be 29.4 and 31.8 ng/mL in the organic extracts. In addition, the method's limit of quantitation for Troc‐norfentanyl and Troc‐noracetylfentanyl were determined to be 88.2 and 95.5 ng/mL, respectively. Collectively, the results presented herein strengthen the use of chloroformate chemistry as an additional chemical tool to confirm the presence of these highly toxic and lethal substances in the environment. [ABSTRACT FROM AUTHOR]

Electron-induced fragmentation of the HFeCo3(CO)12 precursor allows direct-write fabrication of 3D nanostructures with metallic contents of up to >95 at %. While microstructure and composition determine the physical and functional properties of focused electron beam-induced deposits, they also provide fundamental insights into the decomposition process of precursors, as elaborated in this study based on EDX and TEM. The results provide solid information suggesting that different dominant fragmentation channels are active in single-spot growth processes for pillar formation. The use of the single source precursor provides a unique insight into high- and low-energy fragmentation channels being active in the same deposit formation process. [ABSTRACT FROM AUTHOR]

Absolute grand total cross section for electron scattering from CO 2 is obtained in the energy range from 20 eV down to 9 meV with a very narrow electron energy width of 11 meV using the threshold-photoelectron source employing synchrotron radiation. Although the obtained grand total cross section shows the general features of the cross-section behavior known for the low-energy electron scattering from CO 2 , namely the marked rise below 2 eV and the resonance enhancement at about 4 eV, several new features were revealed, especially at the 2 Π u resonance. The energy position for the maxima of the grand total cross section at the 2 Π u resonance appeared to be lower than that has been known. Also found are clear oscillatory structures resolved on the broad enhancement of the grand total cross section at around the 2 Π u resonance. The present measurement also revealed a threshold feature due to the vibrational excitation of asymmetric stretch mode in the grand total cross section. The vibrational excitation cross section for asymmetric stretch mode at the threshold is estimated from the feature. [ABSTRACT FROM AUTHOR]

The characteristic behaviors of the sheath in a collisional dusty plasma composed of nonthermal electrons, ions, neutral atoms, and negatively charged dusts are investigated. To suit the realistic environment, the ionization effect is considered. The result reveals that the peculiarities of the sheath relied on ionization frequency σ , non-thermality parameter b, and dust grains concentration μ. At the sheath edge, the requirement of ion-entering-sheath-velocity enhances with increased b and μ , conversely, reduces with the increment of σ. Nevertheless, when the ionization is pronounced, the impact of b on the Bohm velocity is almost negligible. In the sheath, the increased σ leads to the reduction of the sheath thickness, which results in the redistribution of particles densities. It is noted that ion accumulation is present near the sheath edge. As expected, the present results can give more insight into the interaction processes that happened in the plasma–wall transition region. [ABSTRACT FROM AUTHOR]

Ar:CO2 gas mixtures have recently received research interest due to the possibly beneficial effects of Ar addition to CO2 for CO2 conversion using electrical discharges. For any gas discharge, knowledge of fundamental parameters, such as the effective ionization coefficient, is necessary to optimize the efficiency of the discharge for a particular application. The reduced apparent effective ionization coefficient αea/N is a measure of total ionization. αea/N is influenced by electron impact ionization, electron attachment and also by charge transfer reaction, Penning ionization, and photoionization. This study determined the αea/N of Ar:CO2 gas mixtures in the pressure range of 10–800 Torr and reduced electric field strength E/N range of 40–1200 Td utilizing a steady-state non-self-sustaining Townsend discharge. Experimental results were compared with calculations of Boltzmann equation solver BOLSIG+. Differences between measurements and calculations increased with decreasing CO2 content in the mixture down to 20%, and the differences were highest at low E/N values (below 150 Td). As the simple modification of the model, contribution of ionization of CO2 by Penning transfer from Ar* 3p53d excited states (13.86 eV) was added to the BOLSIG+ calculations, which resulted in good fit of the experimental measurements. Comparison of CO2 addition to Ar with the addition of O2 or N2 revealed that ionization of CO2 or O2 from Ar* 3p53d excited states influences ionization in Ar:CO2 and Ar:O2 mixtures but not in Ar:N2 mixtures, due to the different ionization energies of CO2, O2, and N2. [ABSTRACT FROM AUTHOR]

Cerambyx welensii Küster (Coleoptera: Cerambycidae) is a wood‐borer responsible for the decline of Mediterranean oaks in open woodlands.To establish that contact pheromones are involved in mate recognition of C. welensii, we extracted the cuticular hydrocarbons by solid phase microextraction at pre‐reproductive, beginning and ending of the reproductive period, and by solvent extraction of prothorax and elytra. The extracts were analysed by GC–MS under electron impact and chemical ionization conditions. Cuticular hydrocarbon profiles varied according to the reproductive period, although differences between sexes were not significant. Two compounds, 11/13‐methylheptacosane and 11‐methylnonacosane were more abundant in females at the beginning and ending of the reproductive periods. Compound 11/13‐methylheptacosane was also more representative in female prothorax than in males, and 2‐methyloctacosane was richer in male elytra than in females.We also studied the role of cuticular hydrocarbons in mate recognition in arena bioassays. Treatment of solvent‐washed dead females and glass dummies with one female equivalent (FE) of cuticular extract elicited mating responses in males, especially at the beginning of the reproductive period, with copulation attempts reaching 61.9% on solvent‐washed dead females and 23.8% on dummies. The successive treatment with synthetic compounds approaching a male cuticular profile inhibited male response.Our results confirm that contact pheromones mediate mate recognition in C. welensii. Knowledge of the precise role played by the major compounds 11/13‐methylheptacosane and 11‐methylnonacosane and other minor compounds representative in female prothorax may contribute to the development of novel management strategies against C. welensii. [ABSTRACT FROM AUTHOR]

Vortices are structures known in our daily lives and observed in a wide variety of systems, from cosmic to microscopic scales. Relatively recent studies showed that vortices could also appear in simple quantum systems. For instance, they were observed experimentally and theoretically as isolated zeros in the differential cross section in atomic ionization processes by the impact of charged particles. In this work, we show that the appearance of these quantum vortices as point structures was not due to any intrinsic property of them, but to the use of restrictive geometries in their visualization. In particular, we show that by studying the fully differential cross section for hydrogen ionization by positron impact, these vortex points are actually a manifestation of a more complex and hitherto unexplored structure, a 3D "vortex surface". [ABSTRACT FROM AUTHOR]

In this work, a krypton gas impurity seeding experiment was conducted in a Large Helical Device. Emission lines from the Na-like Kr ion in the extreme ultraviolet wavelength region, such as 22.00 nm, 17.89 nm, 16.51 nm, 15.99 nm, and 14.08 nm, respective to 2 p 6 3 p (2 P 1 / 2 o) − 2 p 6 3 s (2 S 1 / 2) , 2 p 6 3 p (2 P 3 / 2 o) − 2 p 6 3 s (2 S 1 / 2) , 2 p 6 3 d (2 D 3 / 2) − 2 p 6 3 p (2 P 3 / 2 o) , 2 p 6 3 d (2 D 5 / 2) − 2 p 6 3 p (2 P 3 / 2 o) , and 2 p 6 3 d (2 D 3 / 2) − 2 p 6 3 p (2 P 1 / 2 o) transitions, are observed. In order to generate a theoretical synthetic spectrum, an extensive calculation concerning the excitation of the Kr 25 + ion through electron impact was performed for the development of a suitable plasma model. For this, the relativistic multiconfiguration Dirac–Hartree–Fock method was employed along with its extension to the relativistic configuration interaction method to compute the relativistic bound-state wave functions and excitation energies of the fine structure levels using the General Relativistic Atomic Structure Package-2018. In addition, another set of calculations was carried out utilizing the relativistic many-body perturbation theory and relativistic configuration interaction methods integrated within the Flexible Atomic Code. To investigate the reliability of our findings, the results of excitation energies, transition probabilities, and weighted oscillator strengths of different dipole-allowed transitions obtained from these different methods are presented and compared with the available data. Further, the detailed electron impact excitation cross-sections and their respective rate coefficients are obtained for various fine structure resolved transitions using the fully relativistic distorted wave method. Rate coefficients, calculated using the Flexible Atomic Code for population and de-population kinetic processes, are integrated into the collisional-radiative plasma model to generate a theoretical spectrum. Further, the emission lines observed from the Kr 25 + ion in the impurity seeding experiment were compared with the present plasma model spectrum, demonstrating a noteworthy overall agreement between the measurement and the theoretical synthetic spectrum. [ABSTRACT FROM AUTHOR]

Thermal ionization of methenamine (C6H12N4) on the surface of the NaAux intermetallic compound has been studied. It has been established that the processes of decomposition, desorption and ionization of adsorbed compounds, thermally stimulated on the surface, proceed due to the accumulation of energy at the degrees of freedom of the adsorption complex, including the adsorbed compound and a solid, by the mechanism of monomolecular decomposition reactions. In this case, the decomposition of the adsorption complex is accompanied by the desorption of ions that are not in thermal equilibrium with the solid. The uniformity of the temperature dependences of the ion current and their distribution over two groups allowed us to conclude that ions are desorbed from the surface, which correspond to the decays of individual adsorbed molecules, as well as the decays of dimers formed on the surface. The decay of methenamine molecules during thermal ionization occurs in the same way as their decay in vacuum during electron ionization, which indicates the preservation of the bulk structure of methenamine molecules during adsorption and a significant lifetime of the excited state of compounds on NaAux. [ABSTRACT FROM AUTHOR]

In this paper, we investigated the stickiness effect of the Hamilton system of the Hydrogen atom exposed to intense laser field. Even for the one electron system, its Poincare surface of section shows the chaotic and regular parts due to the laser field which can be explained by KAM (Kolmogorov, Arnold, and Moser) theory. The unstable periodic orbit (UPO) in chaotic "sea" was located by variational method and the corresponding stable manifold (SM) and unstable manifold (UM) of the UPO were numerically calculated. It was shown that the dynamics of ionization of the one electron system is governed by the UPO. On one hand, the SM of UPO is well superposed with the recurrence plot, which indicates that the SM overlaps just the stable initial points in phase space. On the other hand, the UM is almost coincide with the densely distributed points on Poincare surface of section. This indicated that the UM is just the ionization channels of the trajectories driven by laser field. Furthermore, the survival probabilities of different regions which gradually cross the UM and SM tangential flow nearby the stable island are studied. They obey an algebraic decaying law. The similar decay trend are also observed on different regions on the UM which possess almost the same decay parameters with that of region nearby the UPO. These observations confirmed that the stability properties of UPO play very important role in the stickiness effect of the phase space nearby the KAM stable islands. [ABSTRACT FROM AUTHOR]

The tin-oxo cage ([R12Sn12O14(OH)6]2+) is an excellent photoresist candidate in extreme ultraviolet lithography (EUVL). Photoionization that leads to plenty of photoelectrons and secondary electrons is an inevitable process upon irradiation by EUV light. The secondary electrons could cause electron blur and decrease the resolution of the photoresist. The utilization and improvement are limited owing to its poorly understood fundamental chemical process, such as exposure to EUV. In this study, the property of complexes (bare cage, binary complexes, and ternary complexes) formed by the combination of the cage and different counterions (methanesulfonate, tosylate, and triflate) was explored using density functional theory (DFT). Extended transition state-nature orbital of chemical valence (ETS-NOCV), charge decomposition analysis (CDA), and atomic dipole moment corrected Hirshfeld (ADCH) atomic charge analyses were carried out to characterize the interaction process (including ionization, electron attachment, and cleavage of the carbon–tin bond) and inherent mechanism. The number and species of counterions are closely associated with ionization and electron attachment; however, they show an inconspicuous effect on the carbon–tin bond energy. Meanwhile, tin free radical could be the reactivity site of ionization (and electron affinity). The activity of radical species is affected by counterions; this could be attributed to the changes in the charge density by diverse counterions, which could be an important factor in why the counterion affects the pattern. In addition, a superb linearity between the ADCH of tin free radical and IP/AP was found, which indicate that the atomic charge could be a simple and reliable substitution of complicated calculation for IP (or AP) to screen suitable counterions and improve the resolution of photoresist. [ABSTRACT FROM AUTHOR]

The equilibrium geometries, and electronic and magnetic properties of phosphorus, cobalt‐phosphorus, and nickel‐phosphorus (Pn+1, CoPn, and NiPn, n = 1–24) clusters have been investigated by using first principle calculations. The doping with cobalt or nickel atom favors the endohedral structures in which the metal atom is encapsulated inside the phosphorus framework, while geometrical structures are metal‐dependent. The growth pattern behaviors and stabilities are examined from the binding energies, the second‐order energy differences, and the HOMO–LUMO gaps. The doping with Co or Ni atom contributes to strengthening the stability of the phosphorus frame with a marked improvement in the case of Ni atom. The total spin magnetic moment is enhanced with doping with Co atom. In contrast, the magnetic moment is quenched in the case of NiPn. Vertical electron affinities and ionization potentials are also reported and discussed. [ABSTRACT FROM AUTHOR]

The electronic structure and ionization spectrum of γ-pyrone (4H-pyran-4-one) were calculated using the third-order algebraic diagrammatic construction method for the single-particle Green function [IP-ADC(3)] and some other high-level quantum chemical methods. The results of calculations were used to interpret its recently recorded photoelectron spectra. New assignments have been proposed for the nature of a series of photoelectron maxima of γ-pyrone located above 12 eV, where, according to calculations, the one-electron ionization pattern is disturbed due to electron correlation effects. The obtained results significantly change the interpretation of the spectrum available in the literature. [ABSTRACT FROM AUTHOR]

We consider the main initial–boundary value (mixed) problems for the nonlinear system of one-dimensional gas ionization equations in the case of constant velocities of gas atoms and ions resulting from ionization. The atom and ion concentrations are the unknowns in this system. We find a general formula for a sufficiently smooth solution of the system. It is shown that mixed problems for the system of one-dimensional ionization equations admit integration in closed-form analytical expressions. In the case of a mixed problem for a finite interval, the analytical solution is constructed using recurrence formulas each of which is defined in a triangle belonging to some triangulation, specified in the paper, of the domain where the unknown functions are defined. [ABSTRACT FROM AUTHOR]

The ionization potentials and total ionization cross sections of glucose and ribose monosaccharide molecules were measured by electron impact at energies up to 70 eV. Using two methods, Hartree–Fock (HF) and density functional theory (DFT), the structure of d- and l-forms of glucose and ribose molecules were calculated using Gaussian. The energy characteristics of the molecular orbitals (MOs) were used to calculate the summarized single ionization cross sections (CS) based on the MOs by the Binary–Encounter–Bethe (BEB) and Gryzinsky (Gryz) models. By normalizing to Gryz-DFT cross sections at thresholds, at 11 eV (Glucose) and 12.65 eV (Ribose), the absolute values of the measured total ionization cross sections of these molecules were obtained. The ionization potentials of glucose and ribose molecules were evaluated from binding HOMO MOs energies and compared with the measured values: 12.25 ± 0.25 eV (Glucose) and 10.46 ± 0.25 eV (Ribose). The contributions of the higher orbitals HOMO, HOMO-1, HOMO-2 to the Gryz-DFT cross section were evaluated. [ABSTRACT FROM AUTHOR]

In this study the applicability of the binary mixture model utilizing the first-order gas-kinetic Chapman–Enskog theory is substantiated for describing diffusion processes at different degrees of ionization of a single-temperature simple gas plasma consisting of three components: atoms, ions and electrons. On the same bases, the obtained expressions for a trinary mixture are applicable to a plasma with a fourth component that is difficult to ionize. The thermal diffusion relations of a trinary mixture are derived, whose peculiarity is the electronic component, which does not affect the diffusion flows of atoms and ions. It is shown that in a highly ionized He arc plasma with developed diffusion and ionization nonequilibrium, thermal diffusion is insignificant. It is noted that when thermodynamic equilibrium is violated, the diffusion coefficients may not change at all or decrease by half at most. [ABSTRACT FROM AUTHOR]

A DFT and TDDFT study has been carried out on Red Nile dye (RN) and on two chalcogens-derivatives in which the carbonyl-oxygen was replaced by Sulfur-(SNR) and Selenium-(SeNR) in order to evaluate the effect of such substitution on their photophysical properties. Inspection of Type I and Type II photoreactions have been achieved exploring the absorption properties, computing spin–orbit coupling, proposing the most plausible deactivation channels leading to the population of excited triplet states and through the analysis of vertical electron affinities and ionization potentials. Our data show a useful bathochromic shift of the lowest energy 1ππ* absorption band as the size of the substituted atom increases combined with an enhancement of the SOC values for the main nπ* → ππ* S1 → T1 deactivation pathways, suggesting a more efficient ISC mechanism for the thio- and seleno-dye. Moreover, the introduction of selenium in the NR dye has the intriguing effect to promote also the electron transfer reaction producing the O2(−)• species through the TypeI mechanism, allowing us to propose that designed dye as a dual TypeI/II PS. Our study supports the strategy to afford heavy-atom effect by using chalcogens showing as it could be successfully exploited to achieve metal-free PSs with desirable properties. [ABSTRACT FROM AUTHOR]

The excitation cross-sections of the 3D and 4D states of atomic hydrogen at low incident energies (from 0.90 to 5.00 Ry) were calculated using the variational polarized orbital method, which is also called the hybrid theory. Up to 12 partial waves (L = 2 to 13) were used to obtain converged cross-sections at high energies. The importance of the long-range forces near the threshold region and the behavior of the cross-sections in that region are indicated. The S, P, and D cross-sections are needed if the total excitation cross-sections are measured in addition to the elastic cross-sections. These cross-sections are also useful if the cascade from the D to the P to the S states is considered in the diagnostics of solar and astrophysical observations. [ABSTRACT FROM AUTHOR]

We have calculated the electron and positron impact ionization of a set of molecules, S F 6 − n H n (n = 0 − 6) , S C l n (n = 1 − 6) , S F n − 1 C l (n = 1 − 6) and S F 5 X (X = C N , C F O) , for which there are much fewer data in the literature. We have optimized the targets, and their electric polarizability is calculated along with their orbital binding and kinetic energies within the Hartree–Fock approximation that serve as input to the Binary Encounter Bethe (BEB) model for both electron and positron ionization. Most of the targets are investigated for the first time, apart from S F 6 , for which we compared our data with various experimental and theoretical data, giving us a good comparison. [ABSTRACT FROM AUTHOR]

A procedure to obtain relativistic expressions for photoionisation angular distribution parameters using the helicity formulation is discussed for open-shell atoms. Electric dipole and quadrupole transition matrix elements were considered in the present work, to study the photoionisation dynamics of the 3s electron of the sodium atom in the vicinity of the dipole Cooper minimum. We studied dipole–quadrupole interference effects on the photoelectron angular distribution in the region of the dipole Cooper minimum. Interference with quadrupole transitions was found to alter the photoelectron angular distribution, even at rather low photon energies. The initial ground and final ionised state discrete wavefunctions of the atom were obtained in the present work using GRASP, and we employed RATIP with discrete wavefunctions, to construct continuum wavefunctions and to calculate transition amplitudes, total cross-sections and angular distribution asymmetry parameters. [ABSTRACT FROM AUTHOR]

The parabolic quasi-Sturmian approach, recently introduced for the calculation of ion–atom ionizing collisions, is adapted and applied here to the single ionization of helium induced by an intermediate-energy proton impact. Within the method, the ionization amplitude is represented as the sum of the products of the basis amplitudes associated with the asymptotic behavior of the continuum states of the two noninteracting hydrogenic subsystems (e − , He +) and (p + , He +) . The p − e interaction is treated as a perturbation in the Lippmann–Schwinger-type (LS) equation for the three-body system (e − , He + , p +) . This LS equation is solved numerically using separable expansions for the proton–electron potential. We examine the convergence behavior of the transition amplitude expansion as the number of terms in the representation of the p − e interaction is increased and find that, for some kinematic regimes, the convergence is poor. This difficulty, which is absent for a higher proton energy impact, is solved by varying the momentum of the auxiliary proton plane wave introduced into the basis function. Fully differential cross-sections are calculated and compared with experimental data for 75 keV protons and the results obtained with the 3C model. [ABSTRACT FROM AUTHOR]

For short-wavelength infrared (SWIR) avalanche photodiodes, a separate absorption, charge, and multiplication design is widely used. AlInAsSb on an InP substrate is a potential multiplication layer with a lattice match to absorber candidates across the SWIR. Our new measurements demonstrate that AlInAsSb on InP is a promising multiplier candidate with a relatively low dark current density of 10−4 A/cm2 at a gain of 30; a high gain, measured up to 245 in this study; and a large differentiation of electron and hole ionization leading to a low excess noise, measured to be 2.5 at a gain of 30. These characteristics are all improvements over commercially available SWIR detectors incorporating InAlAs or InP as the multiplier. We measured and analyzed gain for multiple wavelengths to extract the ionization coefficients as a function of an electric field over the range 0.33–0.6 MV/cm. [ABSTRACT FROM AUTHOR]

Here, we describe our pulsed helium droplet apparatus for spectroscopy of molecular ions. Our approach involves the doping of the droplets of about 10 nm in diameter with precursor molecules, such as ethylene, followed by electron impact ionization. Droplets containing ions are irradiated by the pulsed infrared laser beam. Vibrational excitation of the embedded cations leads to the evaporation of the helium atoms in the droplets and the release of the free ions, which are detected by the quadrupole mass spectrometer. In this work, we upgraded the experimental setup by introducing an octupole RF collision cell downstream from the electron impact ionizer. The implementation of the RF ion guide increases the transmission efficiency of the ions. Filling the collision cell with additional He gas leads to a decrease in the droplet size, enhancing sensitivity to the laser excitation. We show that the spectroscopic signal depends linearly on the laser pulse energy, and the number of ions generated per laser pulse is about 100 times greater than in our previous experiments. These improvements facilitate faster and more reproducible measurements of the spectra, yielding a handy laboratory technique for the spectroscopic study of diverse molecular ions and ionic clusters at low temperature (0.4 K) in He droplets. [ABSTRACT FROM AUTHOR]

Fentanyl analogs are a class of designer drugs that are particularly challenging to unambiguously identify due to the mass spectral and retention time similarities of unique compounds. In this paper, we use agglomerative hierarchical clustering to explore the measurement diversity of fentanyl analogs and better understand the challenge of unambiguous identifications using analytical techniques traditionally available to drug chemists. We consider four measurements in particular: gas chromatography retention indices, electron ionization mass spectra, electrospray ionization tandem mass spectra, and direct analysis in real time mass spectra. Our analysis demonstrates how simultaneously considering data from multiple measurement techniques increases the observable measurement diversity of fentanyl analogs, which can reduce identification ambiguity. This paper further supports the use of multiple analytical techniques to identify fentanyl analogs (among other substances), as is recommended by the Scientific Working Group for the Analysis of Seized Drugs (SWGDRUG). [ABSTRACT FROM AUTHOR]

• Electron interactions in DNA material. • Geant4-DNA electron transport in DNA. • Electron stopping power in DNA. • Electron range in DNA. • Ionisation sampling method. In this study we are introducing an update of the Geant4-DNA physics constructor "option 6" including electron interactions with all constituents of the DNA molecule in addition to those already publicly available for liquid water. The new implementation is based on the interaction cross sections of electrons with the four DNA nucleobases, deoxyribose and phosphoric acid for elastic scattering, electronic excitation and ionisation in the 11 eV – 1 MeV energy range. An additional sampling method to estimate the transferred secondary electron energy produced by ionisation is also introduced and can be optionally activated instead of the classical interpolation method based on the differential cross section tables, thus eliminating the need to upload large data files. The implementation in Geant4-DNA was verified by calculating range and electronic stopping power in the various materials. Good agreement is observed with the data available in the literature, and calculations with the interpolation method and the sampling method showed less than 4% difference. No differences were observed in terms of computational cost. [ABSTRACT FROM AUTHOR]

The valence‐to‐core (VtC) K x‐ray emission spectroscopy (XES) in the tender x‐ray range is emerging as a powerful analytical technique used to study the electronic structure of third‐row elements within complex bulk materials. With dedicated tender x‐ray emission spectrometer coupled with laboratory excitation source, such analysis can be successfully performed also in a smaller lab. In this work, we have gathered VtC x‐ray emission spectra of several sulfur and chlorine compounds measured previously in our home lab using Johansson type tender x‐ray emission spectrometer and MeV proton excitation. Measured spectra are compared to the results of one‐electron density functional theory (DFT) calculations. Theoretical spectra were found in good agreement with the experimental data with few exceptions where systematic discrepancies were observed. The latter was attributed to the simultaneous K and M shell ionization induced by MeV protons, which is not included in the one‐electron DFT theoretical framework. In order to confirm this also experimentally, VtC x‐ray emission spectra of few selected S and Cl compounds induced with three different proton energies were recorded yielding characteristic KM ionization satellite lines, confirmed by their emission energies as well as the dependence of their relative intensity on proton energy. [ABSTRACT FROM AUTHOR]

Partial ionization cross section (PICS) measurements of the cations created through electron impact in the energy range from threshold ionization to 100 eV have been undertaken for 38 cations of 2-butanol, using a HIDEN quadrupole mass spectrometer (EPIC 300) with a mass resolution of 1 amu. These PICSs, which are being presented here for the first time, correspond to the cationic fragments with the highest intensity signal registered in our 2-butanol mass spectrum reported previously (Amorim et al. in Eur J Phys D 76:207, 2022). Experimental and theoretical total ionization cross sections (TICSs) for the electron impact of 2-butanol are also reported here, where the agreement between measured and calculated TICS over their common energy regimes was, allowing for the measurement uncertainties, typically quite good. Based on the previously reported appearance energy values and the PICSs profiles reported here, we propose some ionic fragmentation mechanisms for this molecule. [ABSTRACT FROM AUTHOR]

For the control of fusion reactors, we need to accurately know all the possible reactions and collisional cross sections. Although large-scale trials have been performed over the last decades to obtain this data, many basic atomic and molecular cross section data are missing and the accuracy of the available cross sections need to be checked. Using the available measured cross sections and theoretical predictions of hydrogen atom ionization by proton impact, critical analysis of the data is presented. Moreover, we also present our recent classical results based on the standard classical trajectory Monte Carlo (CTMC) and quasi-classical trajectory Monte Carlo (C-QCTMC) models. According to our model calculations and comparison with the experimental data, recom-mended cross sections for ionization of hydrogen were presented in a wide range of pro-jectile impact energies. We found that, while in the low energy region, the experimental cross sections are very close to the C-QCTMC results, at higher energies, they are close to the results of our standard CTMC results. [ABSTRACT FROM AUTHOR]

Scabies is considered an external parasite notorious for its high prevalence causing severe and contagious skin lesions in humans and animals worldwide. This study has introduced a medicine to treat dogs infested with scabies (variants of Demodex, Sarcoptes, Psoroptes, Otodectes, etc.). The present study offers a no-side-effect herbal formulation to treat dogs infested with scabies. Unlike oral and injectable medicines, which take the form of an ointment and are topically applied on-site, this medicinal formulation can be easily used without concerns over its side effects or consumption dosages. This medicinal formulation requires no skin rinsing due to its herbal and high skin absorption properties, as recovery may take less than a month with a maximum of two times of application. To carry out the experiment, 25 sick dogs with various breeds and ages suspected of scabies were gathered. Following accurate morphological examinations of all the samples, a deep skin chip of the lesion site was provided, which was examined by a microscope. Then, 13 dogs (Mix, Terrier, Pug, Husky, Spitz) were infested with Demodex scabies and 12 dogs (Pittbull, Mix, Shih Tzu, Terrier, Boxer, Setter) with Sarcoptic scabies. The prepared product was topically administered at a constant 2% dosage to the bodies of all the samples. To prepare the ointment, 1 g of Borax (Na2B4O7 ⋅ 10H2O) was first dissolved in 35 g deionized water and heated to 70°C. Then, 45 g of liquid paraffin (CnH2n+2) was mixed with 1 g of Carvacrol (C10H14O) and 1 g of geranium (C10H14O) and stirred well to become a phase. Later, 17 g of the melted beeswax (C15H31COOC30H61) was added to the liquid paraffin compound. In the end, the aqueous phase was added to the oil phase, and the mixture process immediately began in one direction with a glass stirrer and continued until the product cooled down. Essential oils (EO) was obtained by steam distillation of fresh Thyme and Rose-Acented Geranium in a stainless steel distillation apparatus (alembic) for 3 h. The main components of the essential oils used in the formulation were performed using a Hewlett-Packard GC system interfaced with a mass spectrometer equipped with an HP5-MS capillary column (30 m, 0.32 mm, 0.25 µm film thicknesses). For GC-MS detection, electron ionization with ionization energy of 70 eV was used. To examine the presence of scabies, weekly skin sampling was performed, and the treatment continued until 30 days, when no skin chip of the scabies was noted. The findings revealed that the formulation developed no side effects and removed the daily use, as it could be administered once or twice a week. Also, complete recovery of scabies in all the breeds was found to be less than a month at most. This medicinal formulationcan be easily used without concerns over its side effects or consumption dosages. This study introduced a herbal formulation with effective herbal ingredients without any side effects to treat the sarcoptes and demodex parasites; unlike other chemical compounds, this medicinal formulation has no side effects, while some other formulations could develop side effects. [ABSTRACT FROM AUTHOR]