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The electromagnetic interaction, in reality, is screened at a distance, and thus, the screened or cut-off Coulomb potentials are considered to visualize the effect of screening in real situations. The exact analytical expressions for off-shell solutions and transition matrix are constructed for motion in Hulthén-modified rank-one separable potential via the differential equation approach to the problem. The off-shell transition matrix for the said potential has not yet been discussed in the literature. The usefulness of these expressions is examined through some model calculations. [ABSTRACT FROM AUTHOR]

The work reports a comprehensive set of scattering cross sections data of pyrimidine due to electron impact in the energy range from 1 eV to 5 keV. The elastic cross sections are calculated using the single-centre-expansion formalism employing the local potentials. A modified binary-encounter-Bethe model is applied to compute the partial ionization cross sections of cations formed due to the dissociative ionization process. The method is highly simple and yet effective in yielding partial ionization cross sections for majority of cations formed during the dissociation ionization process. We could identify the erroneous partial ionization cross section data reported for cation corresponding to m/z = 28. The total cross sections in the energy range exceeding the ionization threshold are approximated by simply summing the integral elastic and the ionization cross sections. The scattering results obtained are in good agreement with the experimental and theoretical data. We also discuss the importance of the approaches adopted and their limitations. The work is important as the molecule interactions with ionizing radiation are a major cause of incurring damage to biomolecules. The studies are also relevant in areas where electron interactions with molecules are underlying phenomena like astrophysics and plasma physics. [ABSTRACT FROM AUTHOR]

Double-differential cross sections (DDCS) as a function of low-energy electron emission at different impact energies are calculated for the collisions of dressed ions with He atoms by using the four-body formalism of the three-Coulomb wave (3CW-4B) model. We report the energy distribution of ejected electrons with energies varying from 5 to 500 eV for different emission angles. In this work, a model potential is used to represent the interaction between the dressed projectile and the active electron of the target. This potential presents a short-range term and a Coulomb long-range term depending on the net charge of the projectile and the number of electrons bound to it. The nine-dimensional integrals for the transition amplitude are partly reduced to a two- and three-dimensional integrals, which can be easily calculated numerically. The present 3CW-4B results are compared with the available experimental data and other theoretical calculations. The results agree favorably well with the existing experimental findings, especially at high-impact energies. We also studied the dependence of the effective charge of the dressed projectile on the electron emission spectra. Furthermore, the DDCS has been calculated in a range of projectile scattering angles (0–2 mrad) along with electron energies (10–300 eV) and discussed the appearance of different structures. [ABSTRACT FROM AUTHOR]

The asteroid impacts can be devastating for the life on the Earth. Thus, mitigation of this unwanted event is of crucial importance, and nuclear devices are state-of-the-art choice. The presented paper focuses on nuclear data validation of silicon and oxygen. Nuclear data validation is an essential task because nuclear data are the deciding factor for energy deposition profiles, which serve as input for subsequent hydrodynamic simulation, thus directly affecting the description of asteroid deflection. The silicon and oxygen in the form of silicate materials are abundant in asteroids. The set of neutron and gamma transport experiments using a primary neutron standard 252Cf neutron source was performed. The fast neutron spectrum in the energy range of 2–10 MeV was measured using a stilbene detector. The best agreement for fast neutron leakage spectra was reached using INDEN evaluation for 28Si and ENDF/B-VIII.0 16O evaluation. Activation foils sensitive in different energy ranges were utilized. The results depend on the examined reaction and distance from the source. Finally, the prompt gamma rays from capture and inelastic scattering were measured by an HPGe detector. With the exception of 28Si(n,n′) 1779 keV peak, other prompt gamma production peaks show significant discrepancies. The calculations for comparisons of different transport libraries were performed using Monte Carlo MCNP6.2 code. The results show the necessity of further improvement of evaluations for oxygen and silicon. • Energy deposition profile highly depends on used transport library. • Effect of different transport libraries on calculations. • Measurement of leakage neutron spectra from sand cylinder • Measurement of reaction rates of activated materials. • Measurement of prompt gammas. [ABSTRACT FROM AUTHOR]

In the present work, we study the scattering for a black hole described by the canonical acoustic metric with Lorentz violation using asymptotic and numerical methods. In this scenario, we also check the effects of quasinormal modes and the acoustic shadow radius. In the eikonal limit the relationship between the shadow radius and the real part of the quasinormal frequency is preserved. [ABSTRACT FROM AUTHOR]

Four-body formalism of the three-Coulomb wave (3CW-4B) model has been employed to investigate the simultaneous ionization and excitation of He by the impact of fast electron and positron. In this method, the incident wave is described by a plane wave, and the final state wavefunction is a product of the three-Coulomb wave due to the correlated motion of the three unbound charged particles. The triple differential cross sections (TDCS) are calculated and analysed for both the asymmetric coplanar and perpendicular geometries for the incident energies of 0.57, 1.5, and 5.5 keV at several electron emission energies. The distinguishing features have been noted in the angular distribution of the ejected electron. A significant difference in the TDCS structure, especially in the region of binary and recoil peak is found by choosing two different forms of bound state wave function of He in its ground state. The results of the 3CW-4B model are compared to the available experimental and theoretical findings. We find a very good agreement between the present result and the experimental data for pure single ionization, whereas some disagreement has been found in the process of simultaneous ionization with excitation to the n=2 state of H e + . Finally, by changing the sign of the projectile’s charge, significant differences have been observed between the two sets of results for electron and positron impact. [ABSTRACT FROM AUTHOR]

Simple Summary: The six-banded armadillo (Euphractus sexcintus) is included in the International Union for Conservation of Nature (IUCN) as being of the least concern, mainly due to its wide distribution and large population. Nonetheless, in recent years, its population is deploying in specific areas as a consequence of human activities. The scarce literature regarding the anatomy of this species leads us to investigate the normal six-banded armadillo sinuses and nasal passages using modern imaging techniques such as computed tomography (CT) combined with anatomical cross-sectioning to acquire helpful information on the structures that comprise this region. This research aimed to study the rostral part of the head of the six-banded armadillo, applying advanced imaging techniques such as CT. Furthermore, by combining the images obtained through this technique with anatomical cross-sections, an adequate description of the structures that constitute the rostral part of the head of this species is presented. This anatomical information could provide a valuable diagnostic tool for the clinical evaluation of different disorders in the six-banded armadillo's nasal cavity and paranasal sinuses. [ABSTRACT FROM AUTHOR]

Introduction: Charged Particle Therapy plays a key role in the treatment of deep-seated tumours, because of the advantageous energy deposition culminating in the Bragg peak. However, knowledge of the dose delivered in the entrance channel is limited by the lack of data on the beam and fragmentation of the target. Methods: The FOOT experiment has been designed to measure the cross sections of the nuclear fragmentation of projectile and target with two different detectors: an electronic setup for the identification of Z > 3 fragments and a nuclear emulsion spectrometer for Z < 3 fragments. In this paper, we analyze the data taken by exposing four nuclear emulsion spectrometers, with C and C2H4 targets, to 200 MeV/n and 400 MeV/n oxygen beams at GSI Helmholtzzentrum für Schwerionenforschung (Darmstadt, Germany), and we report the charge identification of produced fragments based on the controlled fading induced on nuclear emulsion films. Results: The goal of identifying fragments as heavy as lithium has been achieved. Discussion: The results will contribute to a better understanding of the nuclear fragmentation process in charged particle therapy and have implications for refining treatment planning in the presence of deep-seated tumors. [ABSTRACT FROM AUTHOR]

In this work a theoretical study for photoionization of Ethylene oxide is presented. The photoionization cross section (PICS) for each of the nine valence orbitals and also the summed cross sections are presented. Electronic structure calculations are done to obtain the required molecular properties and the Variational Schwinger method with Padé approximants is used to calculate the PICS. The results are shown in four different approaches: dipole-length/velocity form, static-exchange and static-exchange-polarization levels. The partial PICS for each orbital shows which symmetries of continuum states are responsible for resonance features and how the polarization effects affect the cross sections magnitudes near the threshold. PICS calculations indicate which parent ion state is generated according to the corresponding ionization energies. A correlation is proposed suggesting that the different ionic fragments can be preferentially produced by different electronic states of the parent ion, based on their ionic fragment appearance energies. The summed cross section of all valence orbitals of Ethylene oxide is compared with the results of Acetaldehyde and the analysis suggests that the PICSs, in a given energy range, can be used to identify these isomers. A comparison of our results for EtO and Acetaldehyde with available experimental results for Acetaldehyde and Ethenol demonstrated the the results of three isomers are similar in magnitude in the energy range from 9 to 12 eV. Furthermore, for acetaldehyde, we observed quantitative agreement with the experiment, indicating the reliability of our calculations. [ABSTRACT FROM AUTHOR]

The paper considers collisions involving spin polarized alkali Na and Cs atoms in the ground state. The complex cross sections for spin exchange and the elastic scattering cross sections of the considered atoms are calculated in the energy range from 10–4 to 10–2 a.u. [ABSTRACT FROM AUTHOR]

Radionuclide-based diagnostics and therapy require proper selection of production nuclear reaction based on knowledge of the production excitation functions and the achievable yields completed with data on the formation of possible impurities. In the present work the existing IAEA recommended cross section data database for production of therapeutic isotopes is extended to production of the 47Sc,47Ca(47Sc), 58mCo, 71As(71Ge), 71Ge, 77Br, 77Kr(77Br), 80mBr, 103Pd, 103Pd(103mRh), 103Ru(103mRh), 105Rh, 117mSn, 119Sb, 119mTe(119Sb), 134Ce, 135La, 149gTb, 161Tb, 165Er, 165Tm(165Er), 167Tm, 197mHg, 197gHg, 198gAu, and 230Pa(230U) radioisotopes. Nearly 60 nuclear reactions are presented and discussed. The new recommended cross-section data and their uncertainties for the production of these 21 radionuclides will be available on the Web page of the IAEA Nuclear Data Section at https://nds.iaea.org/radionuclides and also at the IAEA medical portal https://nds.iaea.org/medportal. [ABSTRACT FROM AUTHOR]

Although the Pöschl-Teller potential is widely known for its ability to describe diatomic molecular energy spectra and vibrational excitations, the current effort focuses on parameterizing the above-mentioned potential for nuclear systems. The differential equation methodology to the problem in the representation space leads to the derivation of regular and Jost solutions for the Pöschl-Teller potential. For nucleon-nucleon and nucleon-nucleus systems, bound state energies and scattering phase shifts are computed using the derived Jost function. Using the phase parameters, the elastic scattering cross sections and analyzing powers have been calculated. The outcomes closely match the experimental ones. [ABSTRACT FROM AUTHOR]

In structural design, plastic capacities of cross sections are of great importance for evaluating the capacity of steel members. Moreover, when it comes to problems of member stability, states of partial plasticisation are of interest as well. Depending on the cross section geometry and the material law to be considered, the determination can be challenging. This particularly applies to load conditions characterised by shear stress states, as for instance in the case of primary torsion (St. Venant's torsion). Simplifications are therefore often made with regard to the cross section geometry and engineering models are applied if the plastic limit moment of primary torsion Mpl,xp is to be determined. However, numerical methods allow a precise determination of properties and stress distributions of arbitrary cross section. In the present study, corresponding finite element formulations are combined with a plasticity algorithm for torsional analysis considering effects of nonlinear isotropic hardening. The approach approximates the nonlinear material law by a multilinear curve, which is stepwise evaluated based on linear hardening formulations. It allows determining states of partial cross section plasticisation for any strain or deformation state as well as the identification of the plastic limit capacity of the cross section. Results of the implemented algorithm are presented and verified for different common steel profiles showing excellent agreement to comparative studies.

State-selective single-electron-capture in collisions of dressed and bare projectiles with helium atoms are investigated by means of the prior-version of the four-body formalism of the target continuum distorted-wave approximation with a long-range Coulomb effects arising from the relative motion of the scattering aggregates. Here, we choose H e 2 + and C 4 + ions as bare and dressed projectiles due to the availability of experimental data in the literature and impact energy varies from 10 to 600 keV/amu. For a dressed projectile, the passive electron plays the role of screening to the projectile nucleus. In the initial channel, the perturbation potential due to the interaction between the dressed projectile and the active electron(s), is approximated by a model potential that contains both the short-range and long-range parts. Coulomb continuum states of the active electron in the field of residual target ion as well as long-range Coulomb effects for the relative motion are incorporated in the final state wavefunction. State-selective total and projectile angular-differential cross sections for single-electron-capture have been calculated. Numerical results for state-selective total cross sections show good agreement with the available theoretical and experimental findings. Moreover, a prominent maxima and minima are observed in the projectile angular differential cross sections as impact energy decreases and its position moves to lower projectile scattering angle. Finally, the validity of the present model is critically assessed in comparison with the existing experimental data. [ABSTRACT FROM AUTHOR]

During the past five decades, classical dynamics have been systematically used to gain insight on collision processes between charged particles and photons with atomic and molecular targets. These methods have proved to be efficient for systems in which numerical intensive quantum mechanical methods are not yet tractable. During the years, reaction cross sections for charge exchange and ionization have been scrutinized at the total and differential levels, leading to a clear understanding of the benefits and limitations inherent in a classical description. In this work, we present a review of the classical trajectory Monte Carlo method, its current status and the perspectives that can be envisaged for the near future. [ABSTRACT FROM AUTHOR]

Introduction: Charged Particle Therapy plays a key role in the treatment of deep-seated tumours, because of the advantageous energy deposition culminating in the Bragg peak. However, knowledge of the dose delivered in the entrance channel is limited by the lack of data on the beam and fragmentation of the target.Methods: The FOOT experiment has been designed to measure the cross sections of the nuclear fragmentation of projectile and target with two different detectors: an electronic setup for the identification of Z ≥ 3 fragments and a nuclear emulsion spectrometer for Z ≤ 3 fragments. In this paper, we analyze the data taken by exposing four nuclear emulsion spectrometers, with C and C2H4 targets, to 200 MeV/n and 400 MeV/n oxygen beams at GSI Helmholtzzentrum für Schwerionenforschung (Darmstadt, Germany), and we report the charge identification of produced fragments based on the controlled fading induced on nuclear emulsion films.Results: The goal of identifying fragments as heavy as lithium has been achieved.Discussion: The results will contribute to a better understanding of the nuclear fragmentation process in charged particle therapy and have implications for refining treatment planning in the presence of deep-seated tumors.

A systematic investigation was carried out on the elastic scattering of low- to intermediate-energy electrons ( E 0 = 0.1–1000 eV eV) by acetonitrile (CH3CN). We calculated differential (DCS), integral (ICS), momentum-transfer (MTCS), and total absorption cross sections from 0.1 to 1000 eV energy range using an absorption-effects-implemented ePolyScat-E3 suite of codes, which applies the Schwinger variational method combined with the Padé-approximants technique. Also, the screen-corrected independent atom model was used to compute DCSs, ICSs, and MTCSs from 10–1000 eV impact energies. Present results are compared to other theoretical and experimental data when available. In general, our DCS and MTCS results show a good agreement with available data, however, the ICSs and the resonance features exhibit fair accordance. Our results show two shape-resonance structures: one at about 3.4 eV and a second at about 7 eV. They are labeled as π ∗ and σ ∗ , and comprise the 2 E and 2 A 1 scattering channels, respectively. [ABSTRACT FROM AUTHOR]

In order to investigate the evolution of Chinese lacquering techniques, seven pieces of lacquer Lian from the Warring States Period to the Yuan Dynasty (475 BC–1368 AD) were analyzed by means of cross-section observation, Raman spectroscopy (RS), and thermally assisted hydrolysis and methylation pyrolysis coupled with gas chromatography/mass spectroscopy (Py-GC/MS). The results revealed that the lacquer Lian consisted of a three-layer structure, encompassing a pigment layer on the surface, an undercoat layer in the middle, and a ground layer. The red mineral pigment utilized was cinnabar, while a combination of Chinese lacquer and drying oil served as the primary organic material. Although lacquering techniques had undergone minimal changes from the Warring States Period to the Yuan Dynasty, the species of drying oil had changed, based on the fact that boiled tung oil was found in the ground layer of lacquerware from the Song Dynasty and the Yuan Dynasty. The present research provides direct evidence for the inheritance and development of Chinese lacquer technology. [ABSTRACT FROM AUTHOR]

In view of nuclear structure calculations, the second Pöschl–Teller potential is parameterized to study nucleon–nucleon and nucleon–nucleus elastic scattering. By exploiting the variable phase approach to potential scattering, phase parameters, cross sections, analyzing powers, etc., are computed and compared with earlier works. The calculated cross sections agree with the experiments below 25 MeV within the error bars for the (n-p) and (n-d) systems. [ABSTRACT FROM AUTHOR]

The damped oscillating structures recently revealed by a three parametric formula from the proton “effective” form factor data extracted of the measured total cross section σtotbare(e+e−→pp¯) still seem to have an unknown origin. The conjectures of their direct manifestation of the quark-gluon structure of the proton indicate that they are not specific only of the proton and neutron, but they have to be one’s own, similar to other hadrons. Therefore, the oscillatory structures from the charged pion electromagnetic form factor timelike data, extracted of the process e+e−→π+π− are investigated by using the same procedure as in the case of the proton. The analysis shows the appearance of the oscillating structures in the description of the charged pion electromagnetic form factor timelike data by three parametric formula with a rather large value of χ2/ndf, while the description of the data by the physically well-founded Unitary and Analytic model has not revealed any damped oscillating structures. From the obtained result on the most simple object of strong interactions, one can conclude that damped oscillating structures received from the “effective” proton form factor data are probably generated by a utilization of the improper three parametric formula which does not describe these data with sufficient precision.

This research aimed to study the rostral part of the head of the six-banded armadillo, applying advanced imaging techniques such as CT. Furthermore, by combining the images obtained through this technique with anatomical cross-sections, an adequate description of the structures that constitute the rostral part of the head of this species is presented. This anatomical information could provide a valuable diagnostic tool for the clinical evaluation of different disorders in the six-banded armadillo’s nasal cavity and paranasal sinuses.

Analysis of the latest high–precision cross sections of (α,γ) and (α,n) reactions on 144Sm below the Coulomb barrier is carried out using a consistent parameter set of the statistical model. This prevents the need to use empirical rescaling factors of either γ or neutron widths. Particular attention is paid to uncertainties of the calculated cross sections which are related to the accuracy of the primary data that were used to set up the consistent input parameters. The calculated cross sections are found in good agreement with the new experimental data for the 144Sm(α,n)147Gd reaction; however, the same is not true for the excitation function of 144Sm(α,γ)148Gd which decreases faster at incident energies below ∼12 MeV. An increase of the α-particle direct collective inelastic scattering at lower energies is found responsible for this decrease of the (α,γ) reaction cross sections. The consequent lower nuclear effects may correspond to the Coulomb excitation effect assumed, although in a different manner, within the so-called “α-potential mystery” for the same optical–potential account of α-particle absorption and emission as well.

Introduction: Targeted Radionuclide Therapy is used for the treatment of tumors in nuclear medicine, while sparing healthy tissues. Its application to cancer treatment is expanding. In particular, Auger-electron emitters potentially exhibit high efficacy in treating either small metastases or single tumor cells due to their short range in tissue. The aim of this paper is to study the feasibility of a large-scale production of thulium-167, an Auger-electron emitter radionuclide, in view of eventual systematic preclinical studies.Methods: Proton-irradiated enriched erbium-167 and erbium-168 oxides were used to measure the production cross sections of thulium-165, thulium-166, thulium-167, and thulium-168 utilizing an 18-MeV medical cyclotron equipped with a Beam Transport Line (BTL) at the Bern medical cyclotron laboratory. The comparison between the experimental and the TENDL 2021 theoretical cross-section results were in good agreement. Additional experiments were performed to assess the production yields of thulium radioisotopes in the BTL. Thulium-167 production yield was also measured irradiating five different target materials (167Er2O3, 168Er2O3, natTm2O3, natYb2O3, 171Yb2O3) with proton beams up to 63 MeV at the Injector II cyclotron of Paul Scherrer Institute.Results and Discussion: Our experiments showed that an 8-h irradiation of enriched ytterbium-171 oxide produced about 420 MBq of thulium-167 with a radionuclidic purity of 99.95% after 5 days of cooling time with a proton beam of about 53 MeV. Larger activities of thulium-167 can be achieved using enriched erbium-168 oxide with a 23-MeV proton beam, obtaining about 1 GBq after 8-h irradiation with a radionuclidic purity of

Drones are increasingly vital in numerous fields, such as commerce, delivery services, and military operations. Therefore, it is essential to develop advanced systems for detecting and recognizing drones to ensure the safety and security of airspace. This paper aimed to develop a robust solution for detecting and recognizing drones and birds in airspace by combining a radar system and a visual imaging system, and contributed to this effort by demonstrating the potential of combining the two systems for drone detection and recognition. The results showed that this approach was highly effective, with a high overall precision and accuracy of 88.82% and 71.43%, respectively, and the high F1 score of 76.27% indicates that the proposed combination approach has great effectiveness in the performance. The outcome of this study has significant practical implications for developing more advanced and effective drone and bird detection systems. The proposed algorithm is benchmarked with other related works, which show acceptable performance compared with other counterparts. [ABSTRACT FROM AUTHOR]

We report here the results of a measurement of the scattered versus unscattered neutron fluence on polyethylene determined via neutron activation of multiple natural indium foils from a deuterium-deuterium (D-D) neutron generator. The neutrons were produced by the High Flux Neutron Generator (HFNG) at the University of California, Berkeley, a specially designed source to maximize neutron flux on a sample while minimizing the total neutron yield. During the experiment, approximately 108 n/s were produced with the energies at the indium foils ranging from 2.2 to 2.8 MeV. Both the angle-integrated and the partial angle differential results are consistent with the predictions of the Monte Carlo N-Particle Transport (MCNP) code, using ENDF/B-VII.1. This supports shielding calculations in the fast energy region with high-density polyethylene.

Ni(CO)4, Cr(CO)6, Co(CO)3NO are some of the most common precursors used for focused electron beam induced deposition. Some of the compounds, even though extensively used have high requirements when it comes to handling being, explosives, highly flammable and with high toxicity levels, as is the case of Ni(CO)4. We are employing simulations to determine values hard to determine experimentally, and compare them with DFT calculations and experimental data where available. The use of Quantemol-N cross section simulations for dissociative electron attachment (DEA) at low electron energy in the range of 0–20 eV, gives valuable information on the fragmentation of the molecules, based on their bond dissociation energies, electron affinities and incident electron energies. The values obtained for the cross sections are 0.12 × 10−18 cm2 for Ni(CO)4, 4.5 × 10−16 cm2 for Co(CO)3NO DEA cross-sections and 4.3 × 10−15 cm2 for Cr(CO)6.

Acoustic excitation of a layered sphere by N external and internal point sources is considered. The direct problem is solved by developing a T-Matrix method leading to the analytical determination of all the involved acoustic fields. Low-frequency far-field approximations are derived for different source distributions and scatterer's characteristics. The behaviour of the scattering cross sections is investigated. Several inverse problems are formulated and solved analytically; thus the respective unknown quantities are recovered explicitly. These problems include localization of the sources, determination of their number, identification of the core's type and extraction of the parameters of the scatterer's layers. [ABSTRACT FROM AUTHOR]

The damped oscillating structures recently revealed by a three parametric formula from the proton "effective" form factor data extracted of the measured total cross section σ t o t b a r e (e + e − → p p ¯) still seem to have an unknown origin. The conjectures of their direct manifestation of the quark-gluon structure of the proton indicate that they are not specific only of the proton and neutron, but they have to be one's own, similar to other hadrons. Therefore, the oscillatory structures from the charged pion electromagnetic form factor timelike data, extracted of the process e + e − → π + π − are investigated by using the same procedure as in the case of the proton. The analysis shows the appearance of the oscillating structures in the description of the charged pion electromagnetic form factor timelike data by three parametric formula with a rather large value of χ 2 / n d f , while the description of the data by the physically well-founded Unitary and Analytic model has not revealed any damped oscillating structures. From the obtained result on the most simple object of strong interactions, one can conclude that damped oscillating structures received from the "effective" proton form factor data are probably generated by a utilization of the improper three parametric formula which does not describe these data with sufficient precision. [ABSTRACT FROM AUTHOR]

The calculation of the frequency shifts of the magnetic resonance of K and Li atoms in a K–Li mixture has been carried out. A significant difference in the behavior of the temperature dependences of the frequency shifts for the optical orientation of K or Li atoms is established. [ABSTRACT FROM AUTHOR]

Cross sections of the 12C(n, n+3α) reaction are of great significance in understanding the nuclear reaction mechanism and in the applications of nuclear technology. However, large differences (≈ 200%) exist in the 12C(n, n+3α) cross section data of measurements and evaluations. Using a single crystal chemical vapor deposited (sCVD) diamond detector as an active target, cross sections of the 12C(n, n+3α) and 12C(n, α0)9Be reactions were measured simultaneously in the neutron energy region of 9.50 – 14.67 MeV. The present cross sections of the 12C(n,α0)9Be reaction are consistent with the results of the latest measurement, which confirms the reliability of this work. The measurement results of the 12C(n, n+3α) reaction with uncertainties smaller than 15% contribute to effectively clarify the discrepancies of the measurements and evaluations. To our knowledge, this is the first time to measure the 12C(n, n+3α) cross sections using the diamond detector as an active target. Our method can be used in the future measurements to constrain the 12C(n, n+3α) excitation function in a much wider neutron energy region. R-matrix analysis was carried out for n+12C system using the RAC code in the neutron energy region below 30 MeV. Systematic and reliable calculation results are obtained for various reaction channels.

The focus of this work was on investigating and comparing two methods for calculating the cross sections of muons produced by the decay of heavy-flavor hadrons in pp collisions, which cover the interval 2

Determination and interpretation of Wigner-like photoionisation delays is one of the most active fields of attosecond science. Previous results have suggested that large photoionisation delays are associated with structured continua, but a quantitative relation between photoionisation cross sections and time delays has been missing. Here, we derive a Kramers–Kronig-like relation between these quantities and demonstrate its validity for (anti)resonances. This new concept defines a topological analysis, which rationalises the sign of photoionisation delays and thereby sheds new light on a long-standing controversy regarding the sign of the photoionisation delay near the Ar 3 s Cooper minimum. Our work bridges traditional photoionisation spectroscopy with attosecond chronoscopy and offers new methods for analysing and interpreting photoionisation delays.

During the past five decades, classical dynamics have been systematically used to gain insight on collision processes between charged particles and photons with atomic and molecular targets. These methods have proved to be efficient for systems in which numerical intensive quantum mechanical methods are not yet tractable. During the years, reaction cross sections for charge exchange and ionization have been scrutinized at the total and differential levels, leading to a clear understanding of the benefits and limitations inherent in a classical description. In this work, we present a review of the classical trajectory Monte Carlo method, its current status and the perspectives that can be envisaged for the near future.

232Th/233U fuel cycle is an alternate candidate for future nuclear energy. Neutron-induced fission cross section of 232Th is one of the important nuclear data if using thorium as the fuel in the future. 232Th(n, f) cross sections from 1 to 300 MeV were measured at China Spallation Neutron Source (CSNS) Back-streaming neutron facility (Back-n) relative to 235U(n, f) and n-p scattering. A fast ionization chamber for fission cross section measurement (FIXM) and a proton recoil telescope (PRT) were used to perform the measurement. The neutron energy in this measurement reaches up to 300 MeV which is supposed to be the highest among the current Experimental Nuclear Reaction Data (EXFOR) library. It stands as the only experimental data in the region of 200-300 MeV in EXFOR as well. The experimental and evaluated data of 232Th(n, f) cross section above 60 MeV are scarce, the measurement data of this work will be valuable references for future evaluation in high energy. For the data below 60 MeV, most of our data are more consistent with ENDF/B-VIII.0, excepting in the region of 1-2 MeV where our data are more in favor of CENDL-3.2.

This paper is concerned with the Boltzmann equation based on a continuous internal energy variable to model polyatomic gases with constant specific heats. We propose a family of models for the collision kernel and evaluate the nonlinear Boltzmann collision operator to get explicit expressions for transport coefficients like shear and bulk viscosities, thermal conductivity, depending on the collision kernel parameters. This model is shown to contain as a special case the collision kernel used in the direct simulation Monte Carlo method with the variable hard sphere cross section. Then, we show that it is possible to choose parameters in such a way that we recover various physical phenomena, in particular, experimental data for the shear viscosity, Prandtl number and the ratio of bulk and shear viscosities at the same time. [ABSTRACT FROM AUTHOR]

Closed analytical formulas are derived for the differential and total cross sections of the non-relativistic photoelectric effect in the three main classes of few-electron atomic systems: (a) neutral atoms and positively charged atomic ions which contain more than one bound electron, (b) negatively charged atomic ions, and (c) one-electron atoms and ions. Our procedure developed in this study is a combination of QED methods and results of the density functional theory obtained for atoms and ions. In all these systems the photoelectric effect is considered as photodetachment of the outer-most electron and our analysis is based on the results of density functional theory obtained for the electron density (radial) distribution in these atomic systems. Analytical formulas (similar to ours) for the differential and total cross sections of photoelectric effect for atomic systems from classes (a) and (b) contribute to our understanding of these systems and have not appeared in the literature, to the best of our knowledge. [ABSTRACT FROM AUTHOR]

• TYtool: a software application useful for optimization and maximizing radionuclide production without exceeding the power limits of the target material or holder. • Provides fast computer aided calculations of optimal target thicknesses, particle energies and beam currents based on user input of particle energy, current range, and power limit of target and or holder. • Facilitates graphical representation of many basic plots such as cross section, mass stopping power, activity output, projected range and it is useful for many different particles, reactions and radionuclides. A software application useful for optimization and maximizing radionuclide production without exceeding the power limits of the target material or holder has been developed. The software (TYtool) can be used for target optimization including yield calculations vs time, thickness, and incident energy, W/mm through the target, and automated target thickness optimization with the Makkonen-Craig & Helariutta − or the novel Yield/Wapproach. TYtool also facilitates graphical representation of many basic plots such as cross section, mass stopping power, activity output, projected range and it is useful for many different particles, reactions, radionuclides via the default cross section data base or the import function for cross section and mass stopping power. The software is available for free at: https://gitlab.com/NM_Karolinska_Solna/TYtool. [ABSTRACT FROM AUTHOR]

In this study, we present a detailed analysis of atomic properties for Kr XIX, specifically focusing on the lowest 128 fine-structure levels originating from the 3 s 2 3 p 6 , 3 s 2 3 p 5 3 d , 3 s 3 p 6 3 d and 3 s 2 3 p 4 3 d 2 configurations. We report energy levels, lifetimes, wavelengths, weighted oscillator strengths, and transition probabilities for multipole transition types (E1, E2, M1, and M2). To achieve this, we employed the GRASP2018 code, which implements the fully relativistic multiconfigurational Dirac–Hartree–Fock method and accounts for Breit interaction and quantum electrodynamic effects. We performed another set of calculations using the many-body perturbation theory implemented in the flexible atomic code (FAC). By comparing the results obtained from GRASP2018 and FAC, we established the accuracy and consistency of our calculations. Furthermore, using the relativistic distorted wave theory, we studied electron impact excitation of all transitions to upper levels from the ground and metastable levels and reported excitation cross sections for incident electron energies up to 5 keV. To enhance the practical utility of our findings, we also provided analytical fittings of these cross sections and excitation rate coefficients for their applications in plasma modeling. This work contributes to the atomic properties and excitation cross sections of Kr XIX, addressing a marked gap in the available atomic data. • The atomic data for Kr XIX, required for fusion plasma research, is scarce. • The study reports atomic data for 128 lowest levels of Kr XIX. • MCDHF and MBPT methods are used to calculate the atomic parameters. • The statistical approach is used to assign uncertainty in line strengths. • RDW method is applied to obtain electron impact excitation cross sections. • Excitation rates are determined assuming a Maxwellian electron energy distribution. [ABSTRACT FROM AUTHOR]

Ni(CO)4, Cr(CO)6, Co(CO)3NO are some of the most common precursors used for focused electron beam induced deposition. Some of the compounds, even though extensively used have high requirements when it comes to handling being, explosives, highly flammable and with high toxicity levels, as is the case of Ni(CO)4. We are employing simulations to determine values hard to determine experimentally, and compare them with DFT calculations and experimental data where available. The use of Quantemol-N cross section simulations for dissociative electron attachment (DEA) at low electron energy in the range of 0–20 eV, gives valuable information on the fragmentation of the molecules, based on their bond dissociation energies, electron affinities and incident electron energies. The values obtained for the cross sections are 0.12 × 10−18 cm2 for Ni(CO)4, 4.5 × 10−16 cm2 for Co(CO)3NO DEA cross-sections and 4.3 × 10−15 cm2 for Cr(CO)6. [ABSTRACT FROM AUTHOR]

In present work we study the production of ground and excited charmonium pairs in e - e + → Ψ (n S) + χ cJ (n P) for J = 0,1 and n = 1,2, through leading order (LO) tree-level diagrams ∼ O (α em α s) , which proceed through exchange of a virtual photon and an internal gluon line connecting two quark lines (in the triangle quark loop part of the diagram), in the framework of 4 × 4 Bethe-Salpeter equation, at center of mass energy, s = 10.6 G e V. We have tried to show that the cross sections for this process calculated with use of the four leading order ∼ O (α em α s) diagrams using BSE approach come close to experimental data, which might be mainly due to the consistent treatment of motion of quarks inside the hadrons in the BSE framework. [ABSTRACT FROM AUTHOR]

In the field of nuclear science, obtaining and utilizing nuclear data, including nuclear reaction data, nuclear structure information, and radioactive decay data, is crucial. Neutron-induced nuclear reactions, particularly nuclear cross sections data, are essential for various applications, including reactor design. The EXFOR database is the only international repository for storing nuclear reaction experimental measurement information and data. However, experimental measurement data are often scarce, subject to discrepancies, or even errors, requiring human evaluation. This process can be prone to biases and significant uncertainties. To address these challenges, this study proposes a novel framework, Feature Engineering for Nuclear Reaction Cross Section Generation using Machine Learning (FECSG-ML), which employs machine learning methods to generate nuclear cross sections data, serving as a substitute for evaluating nuclear databases. Given the limited size of the EXFOR database, training a model solely on EXFOR data could lead to underfitting. Therefore, the proposed approach utilizes transfer learning, initially pre-training the model using the ENDF/B-VIII.0 dataset and subsequently fine-tuning it with the EXFOR database. This approach ensures high accuracy where real data are available and enables the learning of characteristics of the evaluation dataset where real data are lacking. Moreover, machine learning techniques are employed to transform discrete nuclear cross sections data into a continuous format, accommodating various isotopes and predicting multiple sets of cross sections data. The framework integrates various machine learning methods and utilizes ensemble learning for result optimization. Experimental results demonstrate that the regression curves generated by the FECSG-ML model align well with EXFOR data points, outperforming the ENDF/B-VIII.0 evaluation database. Furthermore, the nuclear cross sections data generated by the FECSG-ML model are applied in the OpenMC Monte Carlo simulation program to simulate pin fuel assemblies and CANDU reactors, confirming the effectiveness of the model. This study underscores the importance of accurate and reliable nuclear cross sections data and provides a method for substituting the evaluation of nuclear databases., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)