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SDTrimSP is a popular simulation program to compute several effects of the interaction between an impinging ion and a solid, such as ion implantation ranges, damage formation or sputtering of surface atoms. We now introduce a graphical user interface for SDTrimSP to make its operation more accessible for a broad group of users. It is written as a separate Python program and is not restricted to any specific operating system. The interface allows a quick and easy start as well as the direct evaluation of SDTrimSP simulations. Its capabilities are demonstrated here in the form of several example cases, including the dynamic simulations with SDTrimSP, where ion-induced target changes are taken into account. The presented graphical user interface is made freely available to support a large number of users in performing simulations of ion–solid interaction. [ABSTRACT FROM AUTHOR]

The influence of surface morphology modifications on the sputtering yield of thin Fe films by monoenergetic Ar ions is studied by using a highly sensitive quartz crystal microbalance (QCM) technique. The morphology changes are induced by prolonged sputtering up to a total Ar fluence of 8 × 10 21  m −2 . Atomic force microscopy (AFM) measurements are performed to analyse the sample topography before and after irradiation and to determine surface roughness parameters. Numerical modelling with the codes SDTrimSP and SDTrimSP-2D are performed for comparison. Our investigations show that by using the local distribution of projectile impact angles, as derived from AFM measurements, as well as the elemental composition of the samples as an input to the codes SDTrimSP and SDTrimSP-2D the agreement between experiment and simulations is substantially improved. [ABSTRACT FROM AUTHOR]

The roughness of a surface is known to have a strong influence on the sputtering process. Commonly used 1D Monte Carlo codes for calculating sputter yields show good agreement with experimental data only for comparably flat surfaces, whereas local ion incidence angles, shadowing and redeposition influence the sputter yields in both magnitude and angular dependence on rough surfaces. In the present work, we therefore investigated tungsten samples of largely different roughness, characterised by atomic force and confocal microscopy. A highly sensitive quartz crystal microbalance was used to determine sputter yields during ion irradiation. Low ion fluences were applied to ensure that the surface morphology did not change during irradiation. The results were used to benchmark our new ray-tracing simulation code SPRAY , which can take microscopy images without limitations in size as input. SPRAY was furthermore applied to perform systematic simulations for artificially roughened and computer-generated surfaces. A clear result was that the governing parameter for description of the sputtering behaviour is the mean value of the surface inclination angle distribution, rather than the commonly used root mean square roughness. Our simulations show that this parameter is universally applicable for a wide range of different surface structures. [Display omitted] • A decisive roughness parameter for prediction of effective sputter yields was identified. • The code SPRAY was developed for fast sputter simulations with rough surface input. • Microscopy image resolution and size are important for roughness characterisation. [ABSTRACT FROM AUTHOR]

He-induced nanostructured tungsten (so-called W-fuzz) was bombarded with Ar ions under 60° and the dynamic erosion behaviour was experimentally investigated. By using a highly sensitive quartz-crystal-microbalance technique in a particle catcher configuration, the sputtered particles distribution of W-fuzz could be evaluated. In contrast to a flat sample, where sputtered particles are emitted primarily in forward direction, we find that W-fuzz samples emit sputtered particles preferably in backward direction (i.e. in the direction of the incident ion beam). After continuous Ar irradiation of a W-fuzz sample the distribution approaches that of a flat sample. In addition to experimental data we also show modelling results obtained with a state-of-the-art Monte-Carlo (MC) binary collision approximation (BCA) code TRI3DYN in full 3D. Surface morphology changes as monitored by SEM as well as the dynamic sputtering behaviour can be well reproduced by the full 3D MC-BCA code. [ABSTRACT FROM AUTHOR]

We present experimental and simulation data on the oblique angle scattering of heavy Sn ions at 14 keV energy from a Mo surface. The simulations are performed with the binary collision approximation codes TRIM, TRIDYN, TRI3DYN, SDTrimSP, and IMSIL. Additional simulations were performed in the molecular dynamics framework with LAMMPS. Our key finding is the absence of an expected peak in the experimental energy spectrum of backscattered Sn ions associated with the pure single collision regime. In sharp contrast to this, however, all simulation codes we applied do show a prominent single collision signature both in the energy spectrum and in the angular scatter pattern. We discuss the possible origin of this important discrepancy and show in the process, that widely used binary collision approximation codes may contain hidden parameters important to know and to understand. [ABSTRACT FROM AUTHOR]

Magnetite is a relevant mineral component of asteroids as it has been identified in carbonaceous chondrites, on the surface of asteroid Bennu through remote sensing observations, and in samples returned from asteroid Ryugu. However, the effects of space weathering processes on magnetite have not yet been explored. To investigate how this mineral phase responds to space weathering, here we simulate micrometeoroid bombardment and solar wind irradiation of magnetite using pulsed laser and ion irradiation experiments. We performed X-ray photoelectron spectroscopy (XPS), transmission electron microscopy (TEM), and visible to near-infrared (VNIR) reflectance spectroscopy analyses to characterize the chemical, microstructural, and spectral response of magnetite to simulated space weathering. In addition, we carried out ion impact simulations using the SDTrimSP software to evaluate the calculated response of magnetite to 1 keV H+ and 4 keV He+ ions and compared these results to our XPS and TEM results. Ion irradiation simulated ∼750 years on the surface of asteroid Bennu, with a solar-wind appropriate total H:He fluence ratio (∼24). Within this time, depletion of O was observed with H+ and He+ ion irradiation, with significantly greater change via protons due to the larger fluence, where preferential sputtering promotes the formation of a metallic iron layer at the magnetite surface. This suggests that solar wind ions act as reducing agents on Fe oxides, with a fraction remaining implanted in these phases. Indeed, we observe elongated defects contained in a crystalline rim created by He+ implanted ions in the TEM. Pulsed laser irradiation, analogous to micrometeoroid impacts, generates melts on the surface of the magnetite grains. The impact melts and H+-generated metallic iron rims both result in increased VNIR spectral reflectance, but lower fluence He+ implantation has no significant spectral effect. These results suggest that space weathered magnetite could contribute to bright regions detected in remote sensing analyses of the Ryugu and Bennu surfaces by the Hayabusa2 and OSIRIS-REx missions and will contribute to the identification and interpretation of space weathered magnetite in returned samples retrieved from both asteroids. • Surface melts formed as result of pulsed laser irradiation. • 1 keV H+ irradiation produced a ∼35 nm thick Fe-metallic rim on magnetite. • Elongated defects were developed in the magnetite irradiated with 4 keV He+ ions. [ABSTRACT FROM AUTHOR]