Radiation Source Research Articles

Eco-friendly LEDs radiation-assisted photocatalytic mineralization of toxic azure B dye using Bi2MoZnO7 nanocomposite

The present time nanocomposites show highly improved photocatalytic performance in water pollution remediation technology. Herein, BMZ (Bi2MoZnO7) nanocomposite photocatalyst has been synthesized via the co-precipitation method. The structural and morphological studies were interpreted by analytical techniques including X-Ray Diffraction (XRD), Field emission scanning electron microscopy (FE-SEM), Transmission electron microscopy (TEM), and Energy Dispersive X-ray (EDX) analyses. The accomplishment of photocatalysis was determined by the mineralization of toxic azure B dye using a light-emitting diode (LED) as a source of radiation. The characterization studies revealed that the average particle size of BMZ nanocomposite was 28 nm with a flake-like structure having a smooth surface. An EDX spectrum shows the characteristic peaks of Bi, Mo, Zn, and O elements. The parameters such as pH, dye concentration, catalyst weight, reusability of photocatalyst, Fenton’s reagent, CO2, COD, NO3− and SO42− evaluation, and N2 and O2 purging were studied for optimum conditions. Fenton’s reagent test is one of the green approaches in which OH is generated that is utilized for the degradation of toxic azure B dye. The photocatalytic degradation in Fe2+/H2O2/BMZ/Azure B system, high value of the rate constant was recorded as compared to the experiments, performed without BMZ nanocomposite photocatalyst. The eco-friendly LEDs irradiation was applied as a light source material throughout the experiment. The 98 % degradation of toxic azure B dye was observed in 120 min with the highest rate constant (k = 6.1 × 10−4 s−1) in LEDs irradiation.

Upgraded Low-Frequency 3D Lightning Mapping System in North China and Observations on Lightning Initiation Processes

The three-dimensional (3D) low-frequency lightning mapping system (LF-LMS) in north China has been updated. The lightning electric field derivative (dE/dt) sensor and continuous acquisition mode has been newly designed to ensure a capability of entire lightning processes detection, especially weak discharges during lightning the initiation process. The twice cross-correlation delay estimation and the grid iteration nested optimization location algorithm are used to realize the 3D location of the discharge channel, and the location resolution and calculation speed are balanced consequently. The location results of the rocket-triggered lightning demonstrated that the system achieved a high-resolution mapping of lightning discharge channels, which coincided well with the optical images. The horizontal and vertical location error for rocket triggered lightning was less than 40 m in both horizontal and vertical. Intracloud (IC) lightning flashes were observed to be initiated by three different discharge processes, initial breakdown pulse (IBP), narrow bipolar event (NBE), and initial E-change (IEC). The corresponding initial height was 10.5 km, 6.9 km, and 9.2 km, respectively. The upward negative leader was initially located, followed by scatter radiation sources and negative recoil leaders in the lower negative charge region for all cases. The electric field characteristics of the IEC and subsequent IBPs indicated that they are different discharge processes with the same current direction. The IEC process might correspond to the discharge process with continuous current and less noticeable current changes.

Biological Efficacy of Ionizing Radiation Sources on 3D Organotypic Tissue Slices Assessed by Fluorescence Microscopy.

Traditional cell-based radiobiological methods are inadequate for assessing the toxicity of ionizing radiation exposure in relation to the microstructure of the extracellular matrix. Organotypic tissue slices preserve the spatial organization observed in vivo, making the tissue easily accessible for visualization and staining. This study aims to explore the use of fluorescence microscopy of physiologically compatible 3D tissue cultures to assess the effects of ionizing radiation. Organotypic tissue slices were obtained by vibratome, and their mechanical properties were studied. Slices were exposed by two ionizing radiation sources; electron beams (80 Gy and 4 Gy), and soft gamma irradiation (80 Gy and 4 Gy). Two tissue culture protocols were used: the standard (37°C), and hypothermic (30°C) conditions. A qualitative analysis of cell viability in organotypic tissue slices was performed using fluorescent dyes and standard laser confocal microscopy. Biological dosimetry is represented by differentially stained 200-µm thick organotypic tissue sections related to living and dead cells and cell metabolic activity. Our results underscore the ability of fluorescence laser scanning confocal microscopy to rapidly assess the radiobiological effects of ionizing radiation in vitro on 3D organotypic tissue slices.

Comparisons of successful and failed Phase III trials of drugs and biologicals tested for mitigation of oral mucositis in patients being treated with radiotherapy with or without concomitant chemotherapy for cancers of the head and neck.

Oral mucositis (OM) remains a significant toxicity among patients being treated with radiotherapy (RT) alone or with concomitant chemotherapy (CRT) for cancers of the head and neck (HNC). Given its clinical significance as an unmet need and its potential commercial viability, the pharmaceutical industry has been actively pursuing an effective intervention. Despite this interest and activity, only a few agents have been studied in Phase III trials (n = 6). The objective of this study was to identify common features that differentiate successful and failed Phase III OM trials. We used the United States Patent and Trademark Office Patent Public Search database to search patents with "oral mucositis" in the claims. We then searched ClinicalTrials.gov and PubMed to determine if Phase III or Phase II trial data for identified biologics/drugs had been published. We assessed each Phase III and Phase II trial for characteristics that may be associated with trial success or failure. We considered a study as a "success" if the primary endpoint reached statistical significance, and we considered a study as "failure" if the primary endpoint did not reach statistical significance. Of the three successful Phase III trials, one investigated avasopasem manganese (Galera Therapeutics) and two examined palifermin (Amgen). The three failed trials included those evaluating dusquetide (Soligenix), iseganan hydrochloride (IntraBiotics Pharmaceuticals), and clonidine (Monopar Therapeutics). We found that differences in the level of sponsor funding, patient inclusion criteria including radiation source and concomitant chemotherapy regimen, and concordance of primary efficacy outcomes between Phase II and Phase III trials influenced outcomes. To properly design clinical trials for OM in HNC patients, it is important that researchers and sponsors take note of specific study characteristics associated with success or failure, particularly with Phase III trials where the risks and costs are the highest.

Tamping the movement of the laser absorption cutoff position using gold foam hohlraum

In indirect-driven laser fusion experiments, the movement of the laser absorption layer will distort the radiation uniformity on the capsule. The gold foam has advantages in symmetry control and lowering wall plasma blowoff when used in an inertial confinement fusion (ICF) hohlraum. This work investigates the motion of the laser absorption cutoff position using low-density foam gold walls. It is found that the motion of the laser absorption cutoff position can be significantly mitigated through optimal initial low density, tailored to a specific laser shape. For a short square laser pulse, the laser absorption cutoff position remains almost stationary at an initial density of approximately 0.6 g cm−3. For a long-shaped laser pulse, the minimal motion of the laser absorption cutoff position is observed at an initial density of about 0.1 g cm−3. This approach allows for the adjustment of the symmetry of the hohlraum radiation source. The insights gained from this study serve as a crucial reference for optimizing the hohlraum wall density.

Skin cancers are the most frequent cancers in fair-skinned populations, but we can prevent them.

Cancers of the skin are the most commonly occurring cancers in humans. In fair-skinned populations, up to 95% of keratinocyte skin cancers and 70–95% of cutaneous melanomas are caused by ultraviolet radiation and are thus theoretically preventable. Currently, however, there is no comprehensive global advice on practical steps to be taken to reduce the toll of skin cancer. To address this gap, an expert working group comprising clinicians and researchers from Africa, America, Asia, Australia, and Europe, together with learned societies (European Association of Dermato-Oncology, Euromelanoma, Euroskin, European Union of Medical Specialists, and the Melanoma World Society) reviewed the extant evidence and issued the following evidence-based recommendations for photoprotection as a strategy to prevent skin cancer. Fair skinned people, especially children, should minimise their exposure to ultraviolet radiation, and are advised to use protective measures when the UV index is forecast to reach 3 or higher. Protective measures include a combination of seeking shade, physical protection (e.g. clothing, hat, sunglasses), and applying broad-spectrum, SPF 30 + sunscreens to uncovered skin. Intentional exposure to solar ultraviolet radiation for the purpose of sunbathing and tanning is considered an unhealthy behaviour and should be avoided. Similarly, use of solaria and other artificial sources of ultraviolet radiation to encourage tanning should be strongly discouraged, through regulation if necessary. Primary prevention of skin cancer has a positive return on investment. We encourage policymakers to communicate these messages to the general public and promote their wider implementation.

A distributed data processing scheme based on Hadoop for synchrotron radiation experiments.

With the development of synchrotron radiation sources and high-frame-rate detectors, the amount of experimental data collected at synchrotron radiation beamlines has increased exponentially. As a result, data processing for synchrotron radiation experiments has entered the era of big data. It is becoming increasingly important for beamlines to have the capability to process large-scale data in parallel to keep up with the rapid growth of data. Currently, there is no set of data processing solutions based on the big data technology framework for beamlines. Apache Hadoop is a widely used distributed system architecture for solving the problem of massive data storage and computation. This paper presents a set of distributed data processing schemes for beamlines with experimental data using Hadoop. The Hadoop Distributed File System is utilized as the distributed file storage system, and Hadoop YARN serves as the resource scheduler for the distributed computing cluster. A distributed data processing pipeline that can carry out massively parallel computation is designed and developed using Hadoop Spark. The entire data processing platform adopts a distributed microservice architecture, which makes the system easy to expand, reduces module coupling and improves reliability.

Plasmonic excitations in double-walled carbon nanotubes

The interactions of charged particles moving paraxially in multi-walled carbon nanotubes may excite electromagnetic modes. This wake effect has recently been proposed as a potential novel method of short-wavelength high-gradient particle acceleration and for obtaining brilliant radiation sources. In this work, the excitation of wakefields in double-walled carbon nanotubes is studied by means of the linearized hydrodynamic theory. General expressions have been derived for the excited longitudinal and transverse wakefields and related to the resonant wavenumbers which can be obtained from the dispersion relation. In the absence of friction, the stopping power of the wakefield driver, modelled here as a charged macroparticle, can be written solely as a function of these resonant wavenumbers. The dependencies of the wakefields on the radii of the double-walled carbon nanotubes and the driving velocity have been studied. Double-walled carbon nanotubes with inter-wall distances much smaller than the internal radius may be a potential option to obtain higher wakefields for particle acceleration compared to single-walled carbon nanotubes.

Study of dynamics-microphysical-lightning activity characteristics in a tropical hailstorm

Based on three-dimensional lightning locations and S-band polarimetric Doppler radar data, a hailstorm that occurred on Hainan Island on June 4, 2021 was analyzed in detail. The analysis revealed that the flash activity of hailstorms is mainly intracloud (IC) flashes, the cloud-to-ground (CG) flashes frequency were less, positive CG flashes (+CG) were domination in the CG activity before hailfall. The flash frequency appeared “lightning jumps” when hailstorms merging with convective cells, ice hydrometeors also rapidly increased in the clouds of the mixed-phase area in this period, which was beneficial for efficient electrification. The Zdr column and evolution of echo top indicated presence of an intense updraft during the mature stage of the hailstorm. Zdr column depth about 4 km close to 20 °C during the mature stage. Near the time of the hailfall, Zdr column was contraction, due to sinking hail generated downdraft within the cloud. Zdr column after hailfall may be produced by the convergence of downdraft and sea breeze. In combination with the spatiotemporal distribution of the hydrometeors in hailstorms, flash activity was most closely related to graupel and it plays a important role for flashes electrification. The hail plays a minimum role in charge separation. Radiation sources were concentrated between 50 dBZ and 55 dBZ. The spatial distribution of radiation sources indicated possible complex charge structure within hail storm clouds.

UV sources and plastic composition influence microplastic surface degradation: Implications for plastic weathering studies

Microplastic surface properties are dynamic in the environment, as weathering, primarily through photooxidation due to ultraviolet light (UV) exposure, modifies surface chemistry and surface roughness, which can affect the fate, transport and reactivity of microplastics, and therefore any potential environmental risk they may pose. This study aims to investigate and characterise the effect of different UV radiation sources that are typically used in weathering studies (UVA-340 fluorescent lamps, xenon-arc lamps and natural sunlight) on two key properties of microplastics: surface roughness and oxidation level. High- and low-density polyethylene, polypropylene and polystyrene microplastic nurdles (<5 mm) were weathered and characterised using Atomic Force Microscopy and Fourier-Transform Infrared spectroscopy. After two weeks, UVA light was found to significantly increase the carbonyl index of the subject high-density polyethylene and decrease its surface roughness. The subject low-density polyethylene was found to increase in carbonyl index when exposed to all three light sources for two weeks, and reduced in surface roughness when exposed to both xenon-arc and UVA light. Xenon-arc light increased surface roughness on the subject polypropylene after two weeks exposure. The subject polystyrene significantly increased in carbonyl index when exposed to xenon-arc light for two weeks but decreased in surface roughness when exposed to UVA light. Surface oxidation was found to be dependent on polymer type, UV source and additive content, with the data showing a relationship between surface roughness, surface shading and additive content. The results from this study highlight the complexity of microplastic weathering processes and how metrics such as carbonyl index must be applied with caution when estimating how long a plastic has been in the environment.

TO THE EXPEDIENCY OF STUDENTS' TRAINING IN ELECTROMAGNETIC POLLUTION PROTECTION

Problem statement. Electromagnetic radiation is a combination of electric and magnetic radiation, the energy of which, when it affects a given material body, does not cause an ionisation process in it. Natural electromagnetic radiation not only guarantees the proper development of every living organism, but also affects the change of seasons and weather. Humans have disturbed the Earth's natural electromagnetic environment by including devices that emit electromagnetic energy in a wide range of frequencies. Artificial electromagnetic fields accompany us everywhere: at home, at work, on the road, and during leisure. The sanitary and hygienic state of the environment, including the electromagnetic situation in populated cities, is of great hygienic importance for ensuring proper living conditions for the population. The electromagnetic situation in cities and other settlements is created by a large number of radio and electrical equipment for economic, defence and other purposes. The purpose of the article. To conduct a systematic analysis of the impact of electromagnetic radiation from various types of electrical equipment on the environment. It is shown that electromagnetic radiation is dangerous both for the population as a whole, especially for children, and for personnel who operate powerful equipment - sources of electromagnetic radiation. Conclusion. Studies of electromagnetic radiation in the environment show that prolonged exposure to powerful electromagnetic fields can cause illness and even death. Therefore, rules for using artificial sources of electromagnetic radiation should be followed to minimise the damage to both human health and the environment. These rules are not so difficult to follow, but they are quite effective. And for labour protection and civil safety specialists, this knowledge will enable them to create safe working conditions in the workplace.

Analysis of enthalpy and energy conversion efficiency in high-power inductively coupled plasma

The Near-Space Plasma Electromagnetic Science Experimental Research Apparatus is designed for ground-based simulation of plasma sheath and is capable of providing pure, high-enthalpy, and high-density plasma jets. The high enthalpy implies a high plasma state, which can achieve high Mach equivalent simulation in flight conditions. This paper takes this device as the research object and establishes a multi-physics coupling magnetohydrodynamics model to simulate the heat transfer process under high-power conditions. Through numerical simulation, the distribution rules of plasma temperature and enthalpy value under different power states considering the radiation source are obtained. By combining numerical simulation with experimental verification, the simulated enthalpy and energy conversion efficiency results are compared with experimental data, showing good consistency. The study finds that the enthalpy at the center of the jet outlet is higher, increasing from 5.4 MJ/kg to 9.5 MJ/kg when the high-frequency power increases from 150 kW to 426 kW, with an increase of 4.0 MJ/kg. The overall distribution of plasma jet enthalpy exhibits a central peak, gradually decreasing radially from the center to both sides. Meanwhile, during the axial jet injection process, there is a transition in the radial distribution of temperature and enthalpy, shifting from a saddle-shaped distribution at the coil position to an arch-shaped distribution at the nozzle outlet. In this power range, the energy conversion efficiency of the high-frequency power source ranges from 53% to 30%, with both calculated and measured efficiencies decreasing with increasing power. Additionally, the paper discusses the impact of radiation source terms on the distribution of enthalpy in high-power inductive-coupled plasma. In conclusion, the model proposed in this paper can be used to estimate the outlet enthalpy distribution and energy conversion efficiency of the Near-Space Plasma Electromagnetic Science Experimental Research Apparatus, providing data support for the design, control, and application of the device.

Health Effects of Ionizing Radiation on the Human Body.

Radioactivity is a process in which the nuclei of unstable atoms spontaneously decay, producing other nuclei and releasing energy in the form of ionizing radiation in the form of alpha (α) and beta (β) particles as well as the emission of gamma (γ) electromagnetic waves. People may be exposed to radiation in various forms, as casualties of nuclear accidents, workers in power plants, or while working and using different radiation sources in medicine and health care. Acute radiation syndrome (ARS) occurs in subjects exposed to a very high dose of radiation in a very short period of time. Each form of radiation has a unique pathophysiological effect. Unfortunately, higher organisms-human beings-in the course of evolution have not acquired receptors for the direct "capture" of radiation energy, which is transferred at the level of DNA, cells, tissues, and organs. Radiation in biological systems depends on the amount of absorbed energy and its spatial distribution, particularly depending on the linear energy transfer (LET). Photon radiation with low LET leads to homogeneous energy deposition in the entire tissue volume. On the other hand, radiation with a high LET produces a fast Bragg peak, which generates a low input dose, whereby the penetration depth into the tissue increases with the radiation energy. The consequences are mutations, apoptosis, the development of cancer, and cell death. The most sensitive cells are those that divide intensively-bone marrow cells, digestive tract cells, reproductive cells, and skin cells. The health care system and the public should raise awareness of the consequences of ionizing radiation. Therefore, our aim is to identify the consequences of ARS taking into account radiation damage to the respiratory system, nervous system, hematopoietic system, gastrointestinal tract, and skin.

Spherical time-encoded radiation imaging simulations

Radiation source localization is important for nuclear nonproliferation and can be obtained using time-encoded imaging systems with unsegmented detectors. A scintillation crystal can be used with a moving coded-aperture mask to vary the detected count rate produced from radiation sources in the far field. The modulation of observed counts over time can be used to reconstruct an image with the known coded-aperture mask pattern. Current time-encoded imaging systems incorporate cylindrical coded-aperture masks and have limits to their fully coded imaging field-of-view. This work focuses on expanding the field-of-view to 4π by using a novel spherical coded-aperture mask. A regular icosahedron is used to approximate a spherical mask. This icosahedron consists of 20 equilateral triangles; the faces of which are each subdivided into four equilateral triangle-shaped voxels which are then projected onto a spherical surface, creating an 80-voxel coded-aperture mask. These polygonal voxels can be made from high-Z materials for gamma-ray modulation and/or low-Z materials for neutron modulation. In this work, we present Monte Carlo N-Particle (MCNP) simulations and simple models programmed in Mathematica to explore image reconstruction capabilities of this 80-voxel coded-aperture mask.

Radiation of a TM mode from an Open End of a Three-Layer Dielectric Capillary

Abstract Modern trends in beam-driven radiation sources include the interaction of Cherenkov wakefields with open-ended circular waveguides with complicated dielectric linings, with a three-layer dielectric capillary recently proposed to reduce radiation divergence being a representative example [Jiang S et al. 2020 Opt. Lett. 45 5416]. This paper presents a rigorous approach that allows for an analytical description of the electromagnetic processes that occur when the structure is excited by a single waveguide TM mode. In other words, the corresponding canonical waveguide diffraction problem is solved in a rigorous formulation. This is a continuation of our previous papers which considered simpler cases with a homogeneous or two-layer dielectric filling. Here, we use the same analytical approach based on the Wiener-Hopf-Fock technique and deal with the more complicated case of a three-layer dielectric lining. Using the obtained rigorous solution, we discuss the possibility of manipulating the far-field radiation pattern using a third layer made of a low permittivity material.

Controlled terahertz emission and electron localization dynamics in semiconductors

Dynamic localization has been thoroughly studied since 1986 by Dunlap in superlattice structures. However, its implications for terahertz (THz) radiation have not been fully explored. Here, we investigate the interplay between dynamic localization and THz radiation generation in semiconductor structures. Utilizing a two-color laser field, we reveal that intraband current is the primary source of THz radiation. Furthermore, we identify minima in THz radiation yield at specific laser field strengths, indicating the presence of dynamic localization. The relative phase of the two-color laser field and dephasing time can manipulate the extent and range of dynamic localization, thereby influencing the efficiency of THz radiation. Our findings provide valuable insights into simultaneous investigations on materials across different time scales.

Development of heavy mineral filler based FRP composites for (low energy) radiation shielding application

The present study deals with fabricating and characterizing glass fiber reinforced epoxy composites with heavy mineral filler (magnetite particles) for potential low-energy radiation shielding applications. The composite materials were fabricated by the hand layup method. Glass/epoxy composite was used as control sample, and radiation shielding composites were manufactured by mixing 20 and 30% (by weight) magnetite particles with epoxy resin. It was revealed that the tensile properties of the magnetite-modified composites were increased, and the composites containing 30% filler exhibited maximum improvement than the control ones. Further assessment of the composite samples was performed by DMA (Dynamic Mechanical Analysis), TGA (Thermogravimetric Analysis), FTIR (Fourier-Transform Infrared) spectroscopy, water uptake (%), and SEM (Scanning Electron Microscopy) testing. The radiation shielding ability of the control and filler-modified composites was assessed by using a gamma (γ) radiation source (60Co). Then, the shielding efficiency was characterized by radiation-reduced intensity (%), LAC (Linear Attenuation Coefficient), MAC (Mass Attenuation Coefficient), HVL (Half Value Layer), TVL (Tenth Value Layer), and SVL (Sixteenth Value Layer). It was revealed that the 30% magnetite filler content composite experienced relatively good attenuation performance against γ-ray than other studied composites.

Pure CaF2 crystal for fast neutron detection

Pure CaF2 crystals have been widely used for optical functional crystals due to their good optical properties, mechanical properties, and chemical stability. This study discovered the crystal's pulse shape discrimination (PSD), proving it a promising scintillator for fast neutron detection via the 40Ca neutron capture reaction. Luminescence emission spectra were studied by X-ray luminescence measurements. The maximum emission peak was observed between 250 and 300 nm, corresponding to self-trap exciton emission. The crystal response to gamma, alpha, and neutron were studied under 137Cs, 241Am, and 252Cf radiation sources, respectively. The difference in gamma and alpha decay times enabled the PSD capability of pure CaF2. Large neutron reaction cross-sections, PSD capability, and good chemical stability make pure CaF2 crystal candidates for fast neutron beam monitoring detectors. Moreover, the crystal can be used for 40Ca(n,p)40K and 40Ca(n,α)37Ag neutron capture cross-section study.

Femtosecond Dynamics of Fast Electron Pulses in Relativistic Laser-Foil Interactions.

We report the femtosecond time-resolved dynamics of relativistic electron pulses in ultraintense laser-foil interactions, by characterizing the terahertz self-radiation with single-shot ultrabroadband interferometry. Experimental measurements together with theoretical modeling reveal that the electron pulses inherit the duration of the driving laser pulse. We also visualize the electron recirculation dynamics, where electrons remain trapped inside the self-generated electrostatic potential well and rebound back and forth around the thin foil for hundreds of femtoseconds. Our results not only demonstrate an insitu, real-time metrology scheme for electron bursts, but also have important implications for understanding and manipulating the time-domain properties of laser-driven particle and radiation sources.

Estimating the lateral speed of a fast shock driven by a coronal mass ejection at the location of solar radio emissions

Fast coronal mass ejections (CMEs) can drive shock waves capable of accelerating electrons to high energies. These shock-accelerated electrons act as sources of electromagnetic radiation, often in the form of solar radio bursts. Recent findings suggest that radio imaging of solar radio bursts can provide a means to estimate the lateral expansion of CMEs and associated shocks in the low corona. Our aim is to estimate the expansion speed of a CME-driven shock at the locations of radio emission using 3D reconstructions of the shock wave from multiple viewpoints. In this study, we estimated the 3D location of radio emission using radio imaging from the Nançay Radioheliograph and the 3D location of a CME-driven shock. The 3D shock was reconstructed using white-light and extreme ultraviolet images of the CME from the Solar Terrestrial Relations Observatory, Solar Dynamics Observatory, and the Solar and Heliospheric Observatory. The lateral expansion speed of the CME-driven shock at the electron acceleration locations was then estimated using the approximate 3D locations of the radio emission on the surface of the shock. The radio bursts associated with the CME were found to reside at the flank of the expanding CME-driven shock. We identified two prominent radio sources at two different locations and found that the lateral speed of the shock was between $ $ and $ second $ at these locations. Such a high speed during the early stages of the eruption already indicates the presence of a fast shock in the low corona. We also found a larger ratio between the radial and lateral expansion speed compared to values obtained higher up in the corona. We estimated for the first time the 3D expansion speed of a CME-driven shock at the location of the accompanying radio emission. The high shock speed obtained is indicative of a fast acceleration during the initial stage of the eruption. This acceleration leading to lateral speeds in the range of $ second $ is most likely one of the key parameters contributing to the presence of metric radio emissions, such as type II radio bursts.