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The improvements made to ultra-thin windows for X-ray detectors in recent years have allowed for the detection of elements as light as lithium. However, their use with particle induced X-ray emission (PIXE) spectroscopy typically requires the addition of an absorber thick enough to prevent backscattered ions from reaching the detector. This also prevents lower energy (< 1 keV) X-rays from reaching the detector. By using a magnetic field to deflect backscattered ions away, the absorber can be eliminated, allowing for the detection of ultra-low energy X-rays. At the Ion Beam Laboratory of the University of North Texas, a prototype PIXE system using a magnetic deflector has been developed to allow for the detection and measurement of X-rays from light elements using a silicon drift X-ray detector with an ultra-thin window. With an average magnetic flux density of 0.88 T along the center, backscattered protons of an energy up to 1.22 MeV were successfully deflected away from the X-ray detector. Light element PIXE was performed with a 1 MeV proton beam on manganese oxide, sodium chloride and a Hibiscus rosa-sinensis leaf. Elements of 5 ≤ Z ≤ 30 were successfully detected. 

Particulate matter (PM) found in the air is one of the major sources of pollution and air‐borne diseases. Therefore, it is imperative to examine the elemental concentration distribution of the PM to identify the pollutant sources. In this study, it has demonstrated the capabilities of micro‐particle‐induced X‐ray emission (micro‐PIXE) spectroscopy in quantitative analysis of air samples collected from the Old Delhi outdoor market and indoor locations in the Panjab University hostel in the winter months. A 2‐million electronvolts energetic scanning proton micro‐beam (diameter ≈1 µm²) is used in micro‐PIXE experiments generating high‐resolution elemental maps of different regions of interest (ROI). Micro‐PIXE along with the GeoPIXE analysis provides a non‐destructive, standard‐less, and ng/mg level‐sensitive tool for the investigation of elemental distributions and highlighting pixels, which correlates to specific concentration ratios between elements at ROIs, thereby enabling a comprehensive understanding of the source of each elemental particulate. Si, Ca, and K detected in indoor PM suggest the source to soil erosion and crop burning, while high S levels in outdoor PM are primarily associated with coal power plants. Additionally, Sc, Ti, Cr, Mn, and Zn are found in outdoor samples, while indoor locations also contained trace amounts of V, Co, and Cu. 

PIXE analysis was conducted on p8 fisher brand filter paper samples soaked in elemental standard solutions to determine the minimum detectable levels of Al, Si, P, S, Cl, K, Ca, Cr, Fe, Ni, Cu, and Se. All samples were analyzed with beam parameters of 2 µC incident charge, and beam current of less than 2 nA at 2 MeV beam energy. Minimum detectable levels were obtained by analyzing the x-ray spectrum in the GeoPIXE analysis package, and the data for each element would be averaged over all collected spectra. The minimum detectable level in parts per million was found to be on average 9.59 for Al, 4.6 for Si, 3.23 for P, 2.27 for S, 1.82 for Cl, 1.15 for K, 0.88 for Ca, 0.51 for Cr, 0.07 for Mn, 0.54 for Fe, 1.59 for Ni, 2.0 for Zn, 1.55 for Cu, and 6.5 for Se. Minimal deviation from the averaged values was observed, except in cases where samples contained high concentrations of elements with overlapping X-ray energies. 

We have investigated the concentration and correlation between the macro and micro-elements found in an herbal plant named Ocimum sanctum (Tulsi) leaf, using Particle-Induced X-ray Emission (PIXE) spectroscopy. The leaf area was analyzed with a 2 MeV scanning proton micro-beam with a spot size of ~ 1 square micrometer. This study is focused on exploring the correlation between the elemental maps generated using X-ray spectra with micro-PIXE. Two types of correlations i.e., elemental, and concentration-phase correlations were examined. The elemental maps are used to find the relation between the spatial distribution of the elements present in the scanned region while the correlation maps help in understanding which phase corresponds to the region of selected concentration ratios. All the elemental concentrations were determined with the detection limits in ng/mg. The analysis of macro-elements showed that the potassium concentration was highest and phosphorus exhibited the lowest concentration whereas iron was found to be highest in the category of trace or microelements. Moreover, broad-beam runs were also performed on the samples to examine the trend for elemental concentrations. 

This paper discusses the in-situ characterization tools designed to assess radiation tolerance and elemental migration in perovskite materials. With the increasing use of perovskites in various technological applications, understanding their response to radiation exposure is paramount. Ion Beam Induced Charge (IBIC) emerges as a powerful tool for investigating the radiation tolerance of perovskites at the microscale. By employing focused ion beams, IBIC allows for the spatial mapping of charge carriers, offering insights into the material's electronic response to radiation-induced defects. This technique enables researchers to pinpoint areas of enhanced or suppressed charge collection, providing valuable information on the perovskite's intrinsic properties under irradiation. Rutherford Backscattering Spectrometry (RBS) complements the study by offering a quantitative analysis of elemental migration in perovskite materials. Through the precise measurement of backscattered ions, RBS provides a detailed understanding of the elemental composition and distribution within the perovskite lattice after radiation exposure. The integration of IBIC and RBS techniques in in-situ experiments enhances the comprehensive characterization of radiation effects on perovskites. 

ACIGS solar cells are exposed to targeted radiation to probe the front and back interfaces of the absorber to assess the impact of space environments on these systems. These data suggest ACIGS cells are more radiation‐hard than early CIGS devices likely due to the lower defect densities and more ideal interfaces in the ACIGS system. A combination ofJ–Vand external quantum efficiency measurements indicates some improvement in the performance of the device due to the effects of local heating in the dominant ionizing electronic energy loss regime of proton irradiation that anneal the upper CdS/ACIGS interface. However, nonionizing energy losses at the base of the solar cell also appear to inhibit minority carrier collection from the back of the cell at the ACIGS/Mo interface, which is discussed in terms of defect‐mediated changes in the doping profile, the Ga/Ga+In ratio, and impurity composition after proton irradiation. 

Perovskite photovoltaics have been shown to recover, or heal, after radiation damage. Here, we deconvolve the effects of radiation based on different energy loss mechanisms from incident protons which induce defects or can promote efficiency recovery. We design a dual dose experiment first exposing devices to low-energy protons efficient in creating atomic displacements. Devices are then irradiated with high-energy protons that interact differently. Correlated with modeling, high-energy protons (with increased ionizing energy loss component) effectively anneal the initial radiation damage, and recover the device efficiency, thus directly detailing the different interactions of irradiation. We relate these differences to the energy loss (ionization or non-ionization) using simulation. Dual dose experiments provide insight into understanding the radiation response of perovskite solar cells and highlight that radiation-matter interactions in soft lattice materials are distinct from conventional semiconductors. These results present electronic ionization as a unique handle to remedying defects and trap states in perovskites.