Search

This paper mainly discusses the applicability of using soft x‐ray tomography technology to examine the multidimensional structure of metal–organic frameworks, such as their core‐shell and hollow framework, by visually observing their corresponding images in different energy bands by different excitation energies for different elements. The results show that the use of soft x‐ray tomography (SXT) can effectively observe the distribution of metals in the structure, as well as observe the type of hollow pores the metal–organic framework (MOF) possesses. This pioneering evaluation of MOFs via SXT shows excellent performance in the structure identification of multidimensional metal–organic frameworks. [ABSTRACT FROM AUTHOR]

This paper presents numerical characterization of a recently developed compact soft x-ray source based on a nanosecond electric discharge in a gas-filled capillary. When operated in CO2 and Ar:He mixture, the source is capable of producing line radiation in wavelength ranges corresponding to the carbon (4.5–5.0 nm) and water (2.3–4.4 nm) transparency windows. Experimentally obtained trends in emission properties are analyzed using a two-temperature magnetohydrodynamic model, which utilizes mean ion approximation for calculation of basic properties of multicomponent plasma. Spatiotemporal distributions of plasma parameters were obtained for a range of gas pressures corresponding to the studied experimental conditions of the soft x-ray source. Peak values of electron density and electron temperature were analyzed and used to interpret the experimentally obtained trends in dependence of the source operation on inlet gas pressure. [ABSTRACT FROM AUTHOR]

A multigranulation rough set over two universes delivers a unique perspective on the combination of multigranulation information. This paper presents the pessimistic multignualtion rough set over dual universes based on soft binary relations. Firstly, a new pessimistic multigranualtion rough set over dual universes based on two soft binary relations has been developed, and their properties are derived. Then we extend this idea and present pessimistic multigranulation roughness over dual universes based on the finite number of soft binary relations. Finally, we present an example to illustrate our proposed multigranualtion rough set model. [ABSTRACT FROM AUTHOR]

With the advent of soft X-ray imaging enabling global magnetopause detection, it is critical to use reconstruction techniques to derive the 3-dimensional magnetopause location from 2-dimensional X-ray images. One of the important assumptions adopted by most techniques is that the direction with maximum soft X-ray emission is the tangent direction of the magnetopause, which has not been validated in observation so far. This paper analyzes a magnetospheric solar wind charge exchange (SWCX) soft X-ray event detected by XMM–Newton during relatively stable solar wind and geomagnetic conditions. The tangent direction of the magnetopause is determined by an empirical magnetopause model. Observation results show that the maximum SWCX soft X-ray intensity gradient tends to be the tangent of the magnetopause's inner boundary, while the maximum SWCX soft X-ray intensity tends to be the tangent of the magnetopause's outer boundary. Therefore, it is credible to use the assumption that the tangent direction of the magnetopause is the maximum SWCX soft X-ray intensity or its gradient when reconstructing the 3-dimensional magnetopause location. In addition, since these two maxima tend to be the inner and outer boundaries of the magnetopause, the thickness of magnetopause can also be revealed by soft X-ray imaging. [ABSTRACT FROM AUTHOR]

In this work we have updated the list of active galactic nuclei (AGN) detected by INTEGRAL taking into account the new objects listed in the last published INTEGRAL/IBIS survey. We have collected 83 new AGN, increasing the number of INTEGRAL-detected active galaxies (436) by 19%. Half of these new additions are located behind the Galactic plane, and for most of them we have full X-ray coverage, obtained through archival data from Swift/XRT, XMM-Newton, and NuSTAR. The soft X-ray data allowed us to associate each high-energy emitter with a single or multiple X-ray counterpart(s) and characterise the spectral shape of these new AGN by estimating the photon index, the intrinsic absorption, and the 2–10 keV flux. A few cases where two soft X-ray counterparts fall within the INTEGRAL error circle and at least one is classified as an AGN have been found and discussed in detail. Thirty-four sources originally listed as AGN candidates or unidentified objects have been recognised as AGN by employing three diagnostic tests: WISE colours, radio emission, and morphology. For 12 sources among the 34 AGN candidates, we reduced the optical spectra and confirmed their AGN nature, providing also their optical class and redshift. This paper is part of an ongoing effort to keep the INTEGRAL AGN catalogue updated in order to provide the scientific community with a hard X-ray selected sample of well-classified and spectrally characterised active galaxies. [ABSTRACT FROM AUTHOR]

This paper reports some important properties of a dynamic hohlraum radiation source intended to study the high-temperature opacity of medium-Z atoms. The time-resolved axial radiation power in two x-ray diodes gives the time-evolution of an equivalent black-body temperature that peaks at ∼260 eV at stagnation. Time-gated framing pinhole images show that the source comprises an intense high-temperature core that lasts for ∼2 ns preceded by a 10-ns-long lower-temperature implosion phase that emits mostly softer x rays. Combining pinhole images with soft x-ray power gives a time-resolved brightness radiation temperature that reaches 130 eV. Thus, the lower-temperature source could ionize an opacity sample, then the intense high-temperature radiation pulse could measure its opacity. Likewise, the time-integrated spectrum measured with a spherically bent crystal spectrometer is compatible with multiple blackbodies with different temperatures, from 176 to 185 eV. These characterizations suggest that this dynamic hohlraum can be used for high-temperature opacity measurements. [ABSTRACT FROM AUTHOR]

The present special issue is devoted to the experimental, theoretical and computational studies of fundamental features in transport phenomena, structural and phase transitions in various soft and disordered systems (polymers, colloids, glasses, amorphous, crystalline, and composite materials) involved in macroscopically non-equilibrium processes (hydrodynamic flows; non-stationary deformations, heat and mass transfer and so on). Special attention is focused on a detailed microscopical study of the effects of internal structural and phase transformations on macroscopic physical properties and phenomena in the systems under study. [ABSTRACT FROM AUTHOR]

Synchrotron-based soft X-ray tomography (SXT), providing three-dimensional morphology and quantitative distribution of linear absorption coefficient (LAC) of the imaged objects, is widely used in many fields to obtain ultra-structure images, especially in cellular imaging. Off-line fluorescence microscopies (FMs) are combined to identify the type of organelles and status of cells. However, deformation and displacement usually occur during the transfer and loading process, which decreases the precision of two-modal images' registration. In this paper, we report on an on-line FM, at the SXT station (BL07W) of the National Synchrotron Radiation Laboratory (NSRL), which avoids deformation and displacement. Therefore, researchers can easily find the sample and take the useful data without tedious post-processing. Combining SXT with on-line FM, we achieved the identification and high-resolution imaging of an apoptotic cell. The experiments revealed that the LAC of the nucleus of the apoptotic cell was larger than that of a normal cell, which could be explained by nucleus pyknosis of the apoptotic cell. [ABSTRACT FROM AUTHOR]

In this paper, we study the pair of flares X5.4 and X1.3 that occurred on March 7, 2012, which happened in the same active region with a delay of about 1 hour. They were accompanied by long-term (>18 h) γ-radiation with energy of more than 100 MeV. Each of them was accompanied by a fast coronal mass ejection at more than 1800 km/s. The second X1.3 flare is distinguished by small changes in the soft X-ray intensity, temperature, and radiating plasma emission, despite the fact that the hard X-ray intensity at the maximum was comparable to the first X5.4 flare. An analysis of the observations shows: (1) the larger X-ray class of the first X5.4 flare is associated with chromospheric evaporation into low coronal loops, (2) the smaller class of the second X1.3 flare can be explained by chromospheric evaporation only into high coronal loops left after the first flare, (3) in both flares, the acceleration of the coronal mass ejection occurred in the impulsive and prolonged phases both before and after the maxima of hard X-ray bursts, (4) the higher velocity of the coronal mass ejection in X5.4 by 20 Rs is related to the magnitude and duration of the acceleration, and (5) in both flares, relativistic electrons and protons accelerated stochastically during the posteruptive phase. [ABSTRACT FROM AUTHOR]

How does solar wind energy flow through the Earth's magnetosphere, how is it converted and distributed? is the question we want to address. We need to understand how geomagnetic storms and substorms start and grow, not just as a matter of scientific curiosity, but to address a clear and pressing practical problem: space weather, which can influence the performance and reliability of our technological systems, in space and on the ground, and can endanger human life and health. Much knowledge has already been acquired over the past decades, particularly by making use of multiple spacecraft measuring conditions in situ, but the infant stage of space weather forecasting demonstrates that we still have a vast amount of learning to do. A novel global approach is now being taken by a number of space imaging missions which are under development and the first tantalising results of their exploration will be available in the next decade. In this White Paper, submitted to ESA in response to the Voyage 2050 Call, we propose the next step in the quest for a complete understanding of how the Sun controls the Earth's plasma environment: a tomographic imaging approach comprising two spacecraft in highly inclined polar orbits, enabling global imaging of magnetopause and cusps in soft X-rays, of auroral regions in FUV, of plasmasphere and ring current in EUV and ENA (Energetic Neutral Atoms), alongside in situ measurements. Such a mission, encompassing the variety of physical processes determining the conditions of geospace, will be crucial on the way to achieving scientific closure on the question of solar-terrestrial interactions. [ABSTRACT FROM AUTHOR]

We present an analysis of the performance of a broadband secondary radiation source based on a high-gradient laser-plasma wakefield electron accelerator. In more detail, we report studies of compact and ultra-short X-ray generation via betatron oscillations in plasma channels. For the specific working point examined in this paper, determined by the needs of other experiments ongoing at the facility, at ∼0.02 Hz operation rate, we have found ≲ 10 6 photons emitted per shot (with a fluctuation of 50 % ) in the soft X-rays, corresponding to a critical energy of ∼0.8 keV (with a fluctuation of 40%). The source will be implemented for experiments in time-domain spectroscopy, e.g., biological specimens, and for other applications oriented to medical physics. [ABSTRACT FROM AUTHOR]

A numerical study of the effect of betatron oscillations on the second harmonic generation in free‐electron lasers (FELs) is presented. Analytical expressions for the effective coupling strength factors are derived that clearly distinguish all contributions in subharmonics and each polarization of the radiation. A three‐dimensional time‐dependent numerical FEL code that takes into account the main FEL effects and the individual contribution of each electron to the second harmonic generation is presented. Also, the X‐ and Y‐polarizations of the second harmonic are analyzed. The second harmonic was detected in experiments at the Advanced Photon Source (APS) Low Energy Undulator Test Line (LEUTL) and Linac Coherent Light Source (LCLS) in the soft X‐ray regime. The approach presented in the article can be useful for a comprehensive study and diagnostics of XFELs. In the paper, the LCLS and Pohang Accelerator Laboratory X‐ray Free‐Electron Laser (PAL‐XFEL) experiments are modeled. The simulation results are in a good agreement with the experimental data. [ABSTRACT FROM AUTHOR]

X‐ray absorption is a sensitive and versatile tool for chemical speciation. However, when high doses are used, the absorbed energy can change the composition, amount and structure of the native material, thereby changing the aspects of the absorption process on which speciation is based. How can one calculate the dose when X‐ray irradiation affects the chemistry and changes the amount of the material? This paper presents an assumption‐free approach which can retrieve from the experimental data all dose‐sensitive parameters – absorption coefficients, composition (elemental molecular units), material densities – which can then be used to calculate accurate doses as a function of irradiation. This approach is illustrated using X‐ray damage to a solid film of a perfluorosulfonic acid fluoropolymer in a scanning transmission soft X‐ray microscope. This new approach is compared against existing dose models which calculate the dose by making simplifying assumptions regarding the material quantity, density and chemistry. While the detailed measurements used in this approach go beyond typical methods to experimental analytical X‐ray absorption, they provide a more accurate quantitation of radiation dose, and help to understand mechanisms of radiation damage. [ABSTRACT FROM AUTHOR]

In this paper we test if the ∼0.3–15 keV XMM-Newton EPIC pn spectral continuum of IPs can be described by the thermal Comptonization compTT model. We used publicly observations of 12 IPs (AE Aqr, EX Hya, V1025 Cen, V2731 Oph, RX J2133.7+5107, PQ Gem, NY Lup, V2400 Oph, IGR J00234+6141, IGR J17195-4100, V1223 Sgr, and XY Ari). We find that our modeling is capable of fitting well the average spectral continuum of these sources. In this framework, UV/soft X-ray seed photons (with 〈kTs〉 of 0.096 ± 0.013 keV) coming presumably from the star surface are scattered off by electrons present in an optically thick plasma (with 〈kTe〉 of 3.05 ± 0.16 keV and optical depth 〈τ〉 of 9.5 ± 0.6 for plane geometry) located nearby (on top) to the more central seed photon emission regions. A soft blackbody (bbody) component is observed in 5 out of the 13 observations analyzed, with a mean temperature 〈kTbb〉 of 0.095 ± 0.004 keV. We observed that the spectra of IPs show in general two photon indices Γ, which are driven by the source luminosity and optical depth. Low luminosity IPs show 〈Γ〉 of 1.83 ± 0.19, whereas high luminosity IPs show lower 〈Γ〉 of 1.34 ± 0.02. Moreover, the good spectral fits of PQ Gem and V2400 Oph indicate that the polar subclass of CVs may be successfully described by the thermal Comptonization as well. [ABSTRACT FROM AUTHOR]

The SPECIES beamline has been transferred to the new 1.5 GeV storage ring at the MAX IV Laboratory. Several improvements have been made to the beamline and its endstations during the transfer. Together the Ambient Pressure X‐ray Photoelectron Spectroscopy and Resonant Inelastic X‐ray Scattering endstations are capable of conducting photoelectron spectroscopy in elevated pressure regimes with enhanced time‐resolution and flux and X‐ray scattering experiments with improved resolution and flux. Both endstations offer a unique capability for experiments at low photon energies in the vacuum ultraviolet and soft X‐ray range. In this paper, the upgrades on the endstations and current performance of the beamline are reported. [ABSTRACT FROM AUTHOR]

In this work, we present the results of the analysis performed with near edge absorption fine structure spectroscopy of barium edges in a B+BaF2 optical filter. The radiation was generated by a laser-plasma soft X-ray source based on a double-stream gas puff target. The use of a flat-field spectrometer based on a diffraction grating allowed us to collect the absorption spectra of the radiation transmitted by the analyzed optical filter. The results demonstrate the appearance of clear M-edges of barium (M4 and M5). [ABSTRACT FROM AUTHOR]

Anisotropic wet etching of vicinal monocrystalline Si(111)4° wafers was used to obtain blazed gratings that are highly efficient in the soft X-ray (SXR) and extreme ultraviolet (EUV) applications. An improved experimental technology for the fabrication of triangular-grooved Si gratings, both medium-frequency (250 and 500 mm–1) and high-frequency (2500 mm–1) ones, is presented. The stages of forming a Cr-mask for grooves etching, removing Si nubs in order to smooth the profile, and polishing the surface to reduce nanoroughness have been optimized. This paper describes the way of simultaneously (in one process) obtaining a smoothed triangular profile of the Si grating and a polished surface of facets by wet etching. [ABSTRACT FROM AUTHOR]

In this paper, by means of high-resolution photoemission, soft X-ray absorption and atomic force microscopy, we investigate, for the first time, the mechanisms of damaging, induced by neutron source, and recovering (after annealing) of p-i-n detector devices based on hydrogenated amorphous silicon (a-Si:H). This investigation will be performed by mean of high-resolution photoemission, soft X-Ray absorption and atomic force microscopy. Due to dangling bonds, the amorphous silicon is a highly defective material. However, by hydrogenation it is possible to reduce the density of the defect by several orders of magnitude, using hydrogenation and this will allow its usage in radiation detector devices. The investigation of the damage induced by exposure to high energy irradiation and its microscopic origin is fundamental since the amount of defects determine the electronic properties of the a-Si:H. The comparison of the spectroscopic results on bare and irradiated samples shows an increased degree of disorder and a strong reduction of the Si-H bonds after irradiation. After annealing we observe a partial recovering of the Si-H bonds, reducing the disorder in the Si (possibly due to the lowering of the radiation-induced dangling bonds). Moreover, effects in the uppermost coating are also observed by spectroscopies. [ABSTRACT FROM AUTHOR]

Solar extreme-ultraviolet (EUV: 100–1100 Å) radiation rises in the 104 K upper chromosphere and hotter layers extending into the million-degree corona. Much of the EUV normally is not visible in other stars owing to interstellar H i absorption. The present study derived power-law scaling relations for EUV species based on irradiance spectra from the Extreme Ultraviolet Variability Experiment on board the Solar Dynamics Observatory, over the rise and fall of recent sunspot Cycle 24. These relations not only can test solar models, but also allow "invisible" stellar EUV emissions to be reconstructed from more accessible ultraviolet (UV: 1100–3000 Å) proxies, with implications for heating, ionization, and erosion of exoplanet atmospheres by Sun-like hosts. Hot EUV coronal tracers like Si xii 520 Å (8 MK) show strongly curved power laws relative to chromospheric H i 1025 Å Lyβ, as was seen in Paper I for 0.2–2 keV soft X-rays versus Mg ii 2800 Å. The brightest EUV feature, He ii 303 Å, exhibits a nearly 1:1 correlation with Lyβ (and H i 1215 Lyα, but slightly steeper than 1:1 relative to Mg ii). The second brightest, C iii 977 Å, has a shallower power-law slope of ∼0.5. Correlations for low first ionization potential species, such as Mg, Si, and Fe, might be affected by cycle-dependent chemical fractionation. Parameterized flux–flux relations are presented for most of the strong EUV (and selected UV) features, together with fluxes of individual lines and broad EUV wavelength bands at the highs and lows of Cycle 24. [ABSTRACT FROM AUTHOR]

In this paper the back‐side‐illuminated Percival 2‐Megapixel (P2M) detector is presented, along with its characterization by means of optical and X‐ray photons. For the first time, the response of the system to soft X‐rays (250 eV to 1 keV) is presented. The main performance parameters of the first detector are measured, assessing the capabilities in terms of noise, dynamic range and single‐photon discrimination capability. Present limitations and coming improvements are discussed. [ABSTRACT FROM AUTHOR]

The impressive progress in the performance of synchrotron radiation sources is nowadays driven by the so‐called 'ultimate storage ring' projects which promise an unprecedented improvement in brightness. Progress on the detector side has not always been at the same pace, especially as far as soft X‐ray 2D detectors are concerned. While the most commonly used detectors are still based on microchannel plates or CCD technology, recent developments of CMOS (complementary metal oxide semiconductor)‐type detectors will play an ever more important role as 2D detectors in the soft X‐ray range. This paper describes the capabilities and performance of a camera equipped with a newly commercialized backside‐illuminated scientific CMOS (sCMOS‐BSI) sensor, integrated in a vacuum environment, for soft X‐ray experiments at synchrotron sources. The 4 Mpixel sensor reaches a frame rate of up to 48 frames s−1 while matching the requirements for X‐ray experiments in terms of high‐intensity linearity (>98%), good spatial homogeneity (<1%), high charge capacity (up to 80 ke−), and low readout noise (down to 2 e− r.m.s.) and dark current (3 e− per second per pixel). Performance evaluations in the soft X‐ray range have been carried out at the METROLOGIE beamline of the SOLEIL synchrotron. The quantum efficiency, spatial resolution (24 line‐pairs mm−1), energy resolution (<100 eV) and radiation damage versus the X‐ray dose (<600 Gy) have been measured in the energy range from 40 to 2000 eV. In order to illustrate the capabilities of this new sCMOS‐BSI sensor, several experiments have been performed at the SEXTANTS and HERMES soft X‐ray beamlines of the SOLEIL synchrotron: acquisition of a coherent diffraction pattern from a pinhole at 186 eV, a scattering experiment from a nanostructured Co/Cu multilayer at 767 eV and ptychographic imaging in transmission at 706 eV. [ABSTRACT FROM AUTHOR]

This paper presents a novel cantilevered liquid‐nitrogen‐cooled silicon mirror design for the first optic in a new soft X‐ray beamline that is being developed as part of the Advanced Light Source Upgrade (ALS‐U) (Lawrence Berkeley National Laboratory, USA). The beamline is optimized for photon energies between 400 and 1400 eV with full polarization control. Calculations indicate that, without correction, this design will achieve a Strehl ratio greater than 0.85 for the entire energy and polarization ranges of the beamline. With a correction achieved by moving the focus 7.5 mm upstream, the minimum Strehl ratio is 0.99. This design is currently the baseline plan for all new ALS‐U insertion device beamlines. [ABSTRACT FROM AUTHOR]

High harmonic generation (HHG) has been accepted as a tool for tabletop based generation of light source in the XUV and soft x ray region. HHG can produce coherent optical pulses having pulse duration in the femtosecond or even attosecond time region. In this paper, generation of high harmonics are produced by using high power laser system having optical pulses at 6mj pulse energy with pulse duration of 50fs at 10Hz repetition rate. High harmonics in pure Ar, N2 and mixture of the Ar-N2 are used as a generation medium to produce high harmonics. The harmonic signal is increased or decreased depending on the experimental condition. Harmonic yield produced in Ar is stronger than harmonic yield produced in N2 gas. Generation of high order harmonics are observed up to 35H (~54eV corresponding photon energy), and harmonic order from N2 gas is 33H. The mixture of two gas species cause to enhancement of 35H order, which is weakly observed in pure N2 gas. The mechanism of high harmonic generation is explained that strong harmonic signal generated in pure Ar gas helps increase the ionization rate of N2 gas. Thus, the harmonic signal in Ar-N2 is boosted compared the harmonic signal produced in pure N2. The enhancement factor of harmonic yield is from ~2 to 5 for per harmonic order. [ABSTRACT FROM AUTHOR]

Solar wind Magnetosphere Ionosphere Link Explorer (SMILE) is a novel self-standing mission dedicated to observing the solar wind–magnetosphere coupling via simultaneous in situ solar wind/magnetosheath plasma and magnetic field measurements, soft X-ray images of the magnetosheath and polar cusps, and UV images of global auroral distributions. While analyzing the observed images after the launch of SMILE, it will be a challenging task to reconstruct the 3-dimensional surface of the magnetopause from 2-dimensional images. Therefore, one of the most important key issues about SMILE is the reconstruction of magnetopause from X-ray images. This paper will review four main approaches have been developed so far, namely, the boundary fitting approach (BFA), the tangent fitting approach (TFA), the tangential direction approach (TDA), and the computed tomography approach (CTA). We will discuss their scope of application and pros and cons, and hopefully inspire future efforts. [ABSTRACT FROM AUTHOR]

This paper investigates the North–South (N–S) as well as East–West (E–W) distribution and asymmetry in Soft X-ray flares (SXR) activity during the period 1976–2019 which corresponds to solar cycles 21–24. Our results reveal that, cycles 21, 22 and 23 are dominated by southern hemisphere and the cycle 24 is also found to be southern hemisphere dominated using soft X-ray flares data. The cumulative plot indicates a slight excess of X-ray flare events in the southern hemisphere during solar cycles 21, 23 and 24. A significant excess of flare events in the southern hemisphere has been observed in the cumulative plot during cycle 22. The most prolific latitude band in the N–S distribution is the 10°–20° which produced maximum number of soft X-ray flares over solar cycles 21, 22, 23 and 24 whereas no such longitudinal band is observed in the E–W distribution. The time-latitude plot of SXR flares is also constructed to study the behaviour of N–S distribution. It is also revealed in current work that the occurrence (number) of M and X class flares is showing a declining trend since solar cycle 21 till solar cycle 24 thereby violating the Gnevyshev-Ohl (G-O) rule. A significant eastern dominance is being observed till solar cycle 23 but the predominance shifted to western hemisphere during cycle 24. Our analysis reveals that the North–South asymmetry is highly significant in comparison to East–West asymmetry. [ABSTRACT FROM AUTHOR]

Understanding how energy is released in flares is one of the central problems of solar and stellar astrophysics. Observations of high-temperature flare plasma hold many potential clues as to the nature of this energy release. It is clear, however, that flares are not composed of a few impulsively heated loops, but are the result of heating on many small-scale threads that are energized over time, making it difficult to compare observations and numerical simulations in detail. Several previous studies have shown that it is possible to reproduce some aspects of the observed emission by considering the flare as a sequence of independently heated loops, but these studies generally focus on small-scale features while ignoring the global features of the flare. In this paper, we develop a multithreaded model that encompasses the time-varying geometry and heating rate for a series of successively heated loops composing an arcade. To validate, we compare with spectral observations of five flares made with the MinXSS CubeSat, as well as light curves measured with GOES/XRS and SDO/AIA. We show that this model can successfully reproduce the light curves and quasi-periodic pulsations in GOES/XRS, the soft X-ray spectra seen with MinXSS, and the light curves in various AIA passbands. The AIA light curves are most consistent with long-duration heating, but elemental abundances cannot be constrained with the model. Finally, we show how this model can be used to extrapolate to spectra of extreme events that can predict irradiance across a wide wavelength range, including unobserved wavelengths. [ABSTRACT FROM AUTHOR]

The power electronic transformer (PET) or solid-state transformer (SST) is a key technique in the future distribution grid. One of PET's future possible application is the soft normally open points (SNOP) to handle the power and voltage challenge brought by the renewable energy sources. In this paper, a PET-based three-terminal medium-voltage SNOP topology is proposed. The topology consists of three cascade H-bridge (CHB) stages and a multiactive bridge (MAB) stage. The dc voltage control strategy for the proposed PET-SNOP is studied. Two strategies – the CHB+CHB+CHB strategy and CHB+MAB strategies are developed from the existing strategies but they both have some drawbacks. In order to overcome the drawbacks, a novel dc voltage control strategy—CHB×3+MAB strategy is proposed, which combines the advantages and avoids the drawbacks of these two strategies, moreover, it also brings more flexibility and robustness to the dc voltage control. The effectiveness of the proposed PET-SNOP topology as well as the proposed CHB×3+MAB dc voltage control strategy is verified by both simulation and experiment results. [ABSTRACT FROM AUTHOR]

A single-order diffraction transmission grating named spectroscopic photon sieve (SPS) for soft x-ray region is proposed and demonstrated in this paper. The SPS consists of many circular pinholes located randomly, and can realize both free-standing diffractions and the suppression of higher-order differations. In this paper, the basic concept, numerical simulations, and calibration results of a 1000-lines/mm SPS for soft x-ray synchrotron radiation are presented. As predicted by theoretical calculations, the calibration results of a 1000-lines/mm SPS verify that the higher-order diffractions can be significantly suppressed along the symmetry axis. With the current nanofabrication technique, the SPS can potentially have a higher line density, and can be widely used in synchrotron radiation, laser-induced plasma diagnostics, and astrophysics. [ABSTRACT FROM AUTHOR]

Charge exchange (CX) is a semi‐resonant recombination process that can lead to spectral line emission in the X‐ray band. It occurs in nearly any environment where hot plasma and cold gas interact: in the solar system, in comets and planetary atmospheres, and likely astrophysically, in, for example, supernova remnants and galaxy clusters. It also contributes to the soft X‐ray background. Accurate spectral modeling of CX is thus critical to properly interpreting our astrophysical observations, but the commonly used CX models in popular spectral fitting packages often rely on scaling equations and may not accurately describe observations or laboratory measurements. This paper introduces a method that can be applied to high‐resolution CX spectra to directly extract state‐selective CX cross‐sections for electron capture, a key parameter for properly simulating the resulting CX spectrum. [ABSTRACT FROM AUTHOR]

Based on the the third‐order aberration theory of plane‐symmetric optical systems, this paper studies the effect on aberrations of the second‐order accuracy of aperture‐ray coordinates and the extrinsic aberrations of this kind of optical system; their calculation expressions are derived. The resultant aberration expressions are then applied to calculate the aberrations of two design examples of soft X‐ray and vacuum ultraviolet (XUV) optical systems; images are compared with ray‐tracing results using SHADOW software to validate the aberration expressions. The study shows that the accuracy of the aberration expressions is satisfactory. [ABSTRACT FROM AUTHOR]

In this paper, X-ray induced color-tunable long afterglow luminescent material Ca 9-x Tb(PO 4) 7 :xMn2+ was synthesized by high-temperature solid state reaction. The effects of Mn2+ doping concentration on the properties of the samples were studied by XRD, SEM, fluorescence and afterglow spectra. The results showed that there was a very efficient energy transfer between Tb 3+ and Mn 2+ under X-ray excitation, with a transfer efficiency of up to 94.6%, which also contributed to the tunable green-red emission. With the increase of Mn2+ concentration, the green afterglow emissions of Tb3+ mainly at 546.9 nm gradually decreased and even disappeared, while the red afterglow emissions of Mn2+ at 647.3 nm gradually increases due to excellent energy transfer. When the doping concentration of Mn2+ was 0.07, the red afterglow emissions were the strongest. Furthermore, even at low-dose radiation (3 mGy), the sample still possessed excellent afterglow performance, which can persist for more than 5 h. In addition, the samples also showed excellent photostimulated luminescence properties, which can be persist for many cycles by the irradiation of 980 nm laser. The thermoluminescence results revealed that the doping Mn2+ ions can not only enhance the trap concentrations obviously but also created new deep traps with trap depth of 0.864 eV, which thus resulted in better long afterglow luminescence and photostimulated luminescence properties of Ca 9 Tb(PO 4) 7 :Mn2+. [ABSTRACT FROM AUTHOR]

In this paper, we report the absolute measurement of the spectral sensitivity of a bilamellar tube x-ray streak camera (XRSC) over the 0.1–10 keV range equipped with a CsI photocathode for Laser MégaJoule (LMJ) fusion experiments. This calibration of the XRSC is performed in static mode by using two multi-anode x-ray generators. Two silicon drift detectors (SDDs) previously calibrated at the Physikalisch–Technische–Bundesanstalt radiometric laboratory are used as secondary standards. Both x-ray generators work with a specific monochromator for radiometric measurements. In the sub-keV region, a 1 m-grazing incidence Rowland geometry monochromator specifically developed to handle LMJ's x-ray camera is used, whereas for higher energies (>2 keV), a double-crystal monochromator is employed. The absolute spectral sensitivity of the XRSC is obtained by comparing the CCD counts of the XRSC output with the output counts in x-ray lines recorded by the SDD. The results obtained below 1.2 keV are, to our knowledge, the first measurements of the spectral sensitivity of an XRSC in the soft x-ray range with a CsI photocathode. Comparison with a model describing the spectral dependence of the sensitivity of the XRSC revealed that measurements obtained in the sub-keV region are greater than expected, whereas they agree with the model above 4.5 keV. There may be several contributors to this behavior, including the grain morphology of the CsI layer and exposure to air. [ABSTRACT FROM AUTHOR]

The paper describes a nondestructive testing method for the study of structural elements made of lightweight materials. The method is based on the analysis of soft X-ray spectra. The test results for a pipe made of carbon fiber with an average wall thickness of 1 mm are presented. The possibility of constructing maps of the distribution of pipe wall thickness with an accuracy above 10 μm is shown. [ABSTRACT FROM AUTHOR]

Soft X‐ray tomography (SXT) is an imaging technique to visualise whole cells without fixation, staining, and sectioning. For SXT imaging, cells are cryopreserved and imaged at cryogenic conditions. Such 'near‐to‐native' state imaging is in high demand and initiated the development of the laboratory table‐top SXT microscope. As many laboratories do not have access to cryogenic equipment, we asked ourselves whether SXT imaging is feasible on dry specimens. This paper shows how the dehydration of cells can be used as an alternative sample preparation to obtain ultrastructure information. We compare different dehydration processes on mouse embryonic fibroblasts in terms of ultrastructural preservation and shrinkage. Based on this analysis, we chose critical point (CPD) dried cells for SXT imaging. In comparison to cryopreserved and air‐dried cells, CPD dehydrated cells show high structural integrity although with about 3–7 times higher X‐ray absorption for cellular organelles. As the difference in X‐ray absorption values between organelles is preserved, 3D anatomy of CPD‐dried cells can be segmented and analysed, demonstrating the applicability of CPD‐dried sample preparation for SXT imaging. LAY DESCRIPTION: Soft X‐ray tomography (SXT) is an imaging technique that allows to see the internal structures of cells without the need for special treatments like fixation or staining. Typically, SXT imaging involves freezing and imaging cells at very low temperatures. However, since many labs lack the necessary equipment, we explored whether SXT imaging could be done on dry samples instead. We compared different dehydration methods and found that critical point drying (CPD) was the most promising for SXT imaging. CPD‐dried cells showed high structural integrity, although they absorbed more X‐rays than hydrated cells, demonstrating that CPD‐dried sample preparation is a viable alternative for SXT imaging. [ABSTRACT FROM AUTHOR]

Linear off-resonant x-ray Raman techniques are capable of detecting the ultrafast electronic coherences generated when a photoexcited wave packet passes through a conical intersection. A hybrid femtosecond or attosecond probe pulse is employed to excite the system and stimulate the emission of the signal photon, where both fields are components of a hybrid pulse scheme. In this paper, we investigate how attosecond pulse trains, as provided by high-harmonic generation processes, perform as probe pulses in the framework of this spectroscopic technique, instead of single Gaussian pulses. We explore different combination schemes for the probe pulse as well as the impact of parameters of the pulse trains on the signals. Furthermore, we show how Raman selection rules and symmetry consideration affect the spectroscopic signal, and we discuss the importance of vibrational contributions to the overall signal. We use two different model systems, representing molecules of different symmetries, and quantum dynamics simulations to study the difference in the spectra. The results suggest that such pulse trains are well suited to capture the key features associated with the electronic coherence. [ABSTRACT FROM AUTHOR]

Organic–inorganic metal halide perovskites (MHPs) have recently been receiving a lot of attention due to their newfound application in optoelectronic devices, including perovskite solar cells (PSCs) which have reached power conversion efficiencies as high as 25.5%. However, the fundamental mechanisms in PSCs, including the correlation of degradation with the excellent optoelectrical properties of the perovskite absorbers, are poorly understood. In this paper, we have explored synchrotron-based soft X-ray characterization as an effective technique for the compositional analysis of MHP thin films. Most synchrotron-based studies used for investigating MHPs so far are based on hard X-rays (5–10 keV) which include various absorption edges (Pb L-edge, I L-edge, Br K-edge, etc.) but are not suited for the analysis of the organic component in these materials. In order to be sensitive to a maximum number of elements, we have employed soft X-ray-based scanning transmission X-ray microscopy (STXM) as a spectro-microscopy technique for the characterization of MHPs. We examined its sensitivity to iodine and organic components, aging, or oxidation by-products in MHPs to make sure that our suggested method is suitable for studying MHPs. Furthermore, methylammonium triiodide with different deposition ratios of PbI2 and CH3NH3I (MAI), and different thicknesses, were characterized for chemical inhomogeneity at the nanoscale by STXM. Through these measurements, we demonstrate that STXM is very sensitive to chemical composition and homogeneity in MHPs. Thus, we highlight the utility of STXM for an in-depth analysis of physical and chemical phenomena in PSCs. [ABSTRACT FROM AUTHOR]

The Earth's magnetosheath and cusps emit soft X‐rays due to the charge exchange between highly charged solar wind ions and exospheric hydrogen atoms. The Lunar Environment Heliospheric X‐ray Imager and Solar wind Magnetosphere Ionosphere Link Explorer missions are scheduled to image the Earth's dayside magnetosphere system in soft X‐rays to investigate global‐scale magnetopause reconnection modes under varying solar wind conditions. The exospheric neutral hydrogen density distribution, especially the value of this density at the subsolar magnetopause is of particular interest for understanding X‐ray emissions near this boundary. This paper estimates the exospheric density during solar minimum using the X‐ray Multimirror Mission (XMM) astrophysics observatory. We selected an event on 12 November 2008 from the XMM data archive, which detects soft X‐rays of magnetosheath origin while solar wind and interplanetary magnetic field conditions are relatively constant. During the event the location of the magnetopause was measured in situ by the THEMIS mission, thus the location of the solar wind ions responsible for the magnetosheath emission is well constrained by observation. We estimated the exospheric density using the Open Geospace Global Circulation Model (OpenGGCM) and a spherically symmetric exosphere model. The ratio of the magnetosheath plasma flux between the OpenGGCM model and the THEMIS, was nearly 1, which means the magnetohydrodynamic model reasonably reproduces the magnetosheath plasma conditions. The OpenGGCM magnetosheath parameters were used to deconvolve soft X‐rays of exospheric origin from the XMM signal. The lower‐limit of the exospheric density of this solar minimum event is 36.8 ± 11.7 cm−3 at 10 RE subsolar location. Key Points: From 11 years of X‐ray Multimirror Mission‐Newton X‐ray observations, we identified 193 intervals that can be used to estimate the exospheric neutral densityWe derived a solar minimum exospheric neutral density from the 12 November 2008 event using a global MagnetoHydroDynamics model and a simplified exosphere modelThe density estimate is 36.8 cm−3 near the subsolar magnetopause and is likely a lower‐limit value [ABSTRACT FROM AUTHOR]

Copyright of Journal of Synthetic Crystals is the property of Journal of Synthetic Crystals Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

• A soft topological insulator system with imperfect interfaces is modeled. • Tunable phase transitions through finite deformation and adjusting imperfect interfaces' stiffness are studied. • Stiffness of soft imperfect interfaces under finite deformations is given. • Enhancing the stiffness of imperfect interfaces transfers the system from a resonance type to a dispersion type. Acoustic metamaterials, especially the topological insulators, have garnered substantial research attention due to their unique wave properties. Recent research emphasizes the crucial role of imperfect interfaces in accurately simulating and understanding wave propagation within these metamaterials. This paper studies the mechanical properties of soft imperfect interfaces and derives the effects of finite deformations on their stiffness. We present a comprehensive model of a soft Rayleigh beam system that incorporates these interfaces, allowing for the observation of the topological phase transition by altering the distance between them. Our investigation into the impacts of finite deformations and interface stiffness adjustment reveals that longitudinal waves' phase transition points are mainly influenced by interface stiffness. In contrast, transverse waves are predominantly affected by finite deformations. The decisive parameters driving these phenomena are also identified theoretically. The transmission studies of supercells further confirm the presence of topologically protected interface modes and their extensive tunability. Overall, this study offers a novel methodology and framework for managing topological phase transition in composite and soft topological insulator systems. This paper models a soft topological insulator system that integrates the Rayleigh beams with imperfect interfaces. Several methods are utilized to calculate the band structure. The topological phase diagrams are used to investigate the phase transition process. Finally, tunable topologically protected interface modes are studied. [Display omitted] [ABSTRACT FROM AUTHOR]

In this paper, we present multiwavelength observations of the triggering of a failed-eruptive M-class flare from active region NOAA 11302 and investigate the possible reasons for the associated failed eruption. Photospheric observations and nonlinear force-free field extrapolated coronal magnetic field revealed that the flaring region had a complex quadrupolar configuration with a preexisting coronal nullpoint situated above the core field. Prior to the onset of the M-class flare, we observed multiple periods of small-scale flux enhancements in GOES and RHESSI soft X-ray observations from the location of the nullpoint. The preflare configuration and evolution reported here are similar to the configurations presented in the breakout model, but at much lower coronal heights. The core of the flaring region was characterized by the presence of two flux ropes in a double-decker configuration. During the impulsive phase of the flare, one of the two flux ropes initially started erupting, but resulted in a failed eruption. Calculation of the magnetic decay index revealed a saddle-like profile where the decay index initially increased to the torus-unstable limits within the heights of the flux ropes, but then decreased rapidly and reached negative values, which was most likely responsible for the failed eruption of the initially torus-unstable flux rope. [ABSTRACT FROM AUTHOR]

Comprehensive Summary: Hydrogen‐bonded organic networks (HONs) have attracted intense research interest due to their mild synthesis conditions, good solvent processability and strong reproducibility. Most HONs are constructed by electrically neutral organic ligands through intermolecular interactions such as weak hydrogen bonding, π‐π stacking. But there are a few charge‐assisted hydrogen‐bonding networks (CAHONs) constructed by oppositely charged organic components. Under hydrothermal conditions, we successfully synthesized a 3D CAHON (H2CV)(H2BTEC) (1) constructed by H2CV (CV = N,N′‐4,4′‐bipyridine dipropionate) and H4BTEC (H4BTEC = 1,2,4,5‐benzenetetracarboxylic acid) through multiple charge‐assisted hydrogen bonding. Upon soft X‐ray, ultraviolet light or sunlight irradiation under ambient conditions, 1 quickly changes from colorless to blue (1P), and kinetic calculations show that its photochromism meets first‐order dynamics. Interestingly, the colored crystals 1P with long‐lived colored radicals will not fade after being placed for more than two months at room temperature in air, owing to the fact that the photogenerated viologen radicals can be stabilized by the abundant hydrogen bonds, the coplanar pyridinium rings and the slow electron‐hole recombination. Moreover, 1 is a typical direct band gap semiconductor, evidenced by the calculated band gap of 3.24 eV, in agreement with the experimental value of 3.40 eV. In view of its strong colored stability, 1 is designed for distinctive inkless printing. [ABSTRACT FROM AUTHOR]

Photonâ€"axion mixing can create observable signatures in the thermal spectra of isolated, cooling neutron stars. Their shape depends on the polarization properties of the radiation, which, in turn, are determined by the structure of the stellar outermost layers. Here we investigate the effect of mixing on the spectrum and polarimetric observables, polarization fraction and polarization angle, using realistic models of surface emission. We focus on RX J1856.5â€"3754, the only source among the X-ray-dim isolated neutron stars for which polarimetric measurements in the optical band were performed. Our results show that in the case of a condensed surface in both fixed and free-ion limits, the mixing can significantly limit the geometric configurations that reproduce the observed linear polarization fraction of 16.43%. In the case of an atmosphere, the mixing does not create any noticeable signatures. Complementing our approach with the data from upcoming soft X-ray polarimetry missions will allow one to obtain constraints on g Îł a ∼ 10âˆ'11 GeVâˆ'1 and m a ≲ 10âˆ'6 eV, improving the present experimental and astrophysical limits. [ABSTRACT FROM AUTHOR]

The Shanghai soft X-ray Free-Electron Laser facility (SXFEL), which is the first X-ray FEL facility in China, is being constructed in two phases: the test facility (SXFEL-TF) and the user facility (SXFEL-UF). The test facility was initiated in 2006 and funded in 2014. The commissioning of the test facility was finished in 2020. The user facility was funded in 2016 to upgrade the accelerator energy and build two undulator lines with five experimental end-stations. The output photon energy of the user facility will cover the whole water window range. This paper presents an overview of the SXFEL facility, including considerations of the upgrade, layout and design, construction status, commissioning progress and future plans. [ABSTRACT FROM AUTHOR]

We present a method to explore the effect of fluorescence on X‐ray attenuation measurements obtained from X‐ray absorption spectroscopy (XAS). We use the X‐ray extended range technique‐like method (XERT‐like). The experimental setup includes different sized apertures to control the number of secondary X‐rays entering the detector. Comparison of attenuation measurements produced with different aperture combination permit investigation of the effect of fluorescence radiation. In this work, fluorescence has a large impact on the attenuation measurements of thick zinc foils. The correction is energy‐dependent and sample thickness‐dependent and changes the structure and relative amplitudes of oscillations in the near‐edge region. Correction for this systematic is important for absolute measurement, for edge‐jump and edge characterization, and for near‐edge structure and amplitudes. A significant background scattering due to zinc fluorescence from the beamline optics was identified and treated for the first time. The model theory fits the experimental measurements well. The resulting correction is most significant for thicker foils with the 50 μm sample experiencing a shift in attenuation of up to 15.5% for the largest aperture while the 25 and 10 μm samples saw corrections of up to 0.153 and 0.00639% respectively. The standard error from the dispersion and variance was reduced by up to 50.5% after the correction for the 50 μm sample. This enables high‐accuracy data and theoretical and experimental analysis to below 0.03% accuracy. The technology is advanced. There is a cost in preparation and measurement time of less than a factor of two, and the principles are clear and can be routinely implemented on any beamline. This paper focuses on the model and parameters for fluorescence. [ABSTRACT FROM AUTHOR]

PM2.5 is an important global air pollution issue. PM2.5 causes various problems on the environment and human health. Even though PM2.5 of the outdoor air is eliminated by particulate air filters, the chemicals adsorbed on the filtered PM2.5 can be outgassed and introduced into the semiconductor manufacturing facilities and processes, thus causing defects on the semiconductor chips by producing particles and haze as airborne molecular contamination. Therefore, estimating the amount of the outgassing from PM2.5 is a very important factor to control gaseous contaminants in the semiconductor industry. In this paper, the PM2.5 samples at different PM2.5 mass loadings were collected in Xi’an, China and evaluated using the soft X-ray radiolysis method for determining the relation between the outgassing and the PM2.5 mass loading. The PM2.5 samples were also analyzed by several methods for quantifying organic and elemental carbons, water soluble ions, and organic compounds in the PM2.5 samples. The outgassing measured by the soft X-ray method increased linearly with the PM2.5 mass loading, and the chemical analyses explained that the organic carbon (OC) was dominantly detected by the soft X-ray method in the current study. Moreover, the sampling location of the PM2.5 affected on the organic compounds of the PM2.5. [ABSTRACT FROM AUTHOR]

To address the issue of white noise at partial discharge (PD) ultra high frequency (UHF) signal in gas insulated substation (GIS), this paper develops an external sensor and proposes new empirical mode decomposition (EMD) denoising method based on autocorrelation coefficient and similar wavelet soft threshold. Four types of typical GIS defects at the PD UHF signal were obtained through experiment. The autocorrelation coefficient of intrinsic mode functions (IMF) components at the PD UHF signal was computed, the cut-off point between the noise signal dominant mode and the UHF signal dominant mode was found. The similar wavelet soft threshold denoising was performed on the signal which is dominated by the noise signal, all the UHF signals were finally reconstructed. The signal-to-noise ratio computed by the proposed denoising method was compared with the one computed by the wavelet denoising method, the results shows that the proposed denoising method in this paper is more effective than the wavelet denoising method. [ABSTRACT FROM AUTHOR]

Context. High-resolution X-ray spectroscopy has advanced our understanding of the hot Universe by revealing physical properties like kinematics, temperature, and abundances of the astrophysical plasmas. Despite technical and scientific achievements, the lack of scientific products at a level higher than count spectra is hampering complete scientific exploitation of high-quality data. This paper introduces the Catalog of Ionized Emission Lines Observed by the Reflection Grating Spectrometer (CIELO-RGS) onboard the XMM-Newton space observatory. Aims. The CIELO-RGS catalog aims to facilitate the exploitation of emission features in the public RGS spectra archive. In particular, we aim to analyze the relationship between X-ray spectral diagnostics parameters and measurements at other wavelengths. This paper focuses on the methodology of catalog generation, describing the automated line-detection algorithm. Methods. A moderate sample (∼2400 observations) of high-quality RGS spectra available at XMM-Newton Science Archive is used as our starting point. A list of potential emission lines is selected based on a multi-scale peak-detection algorithm in a uniform and automated way without prior assumption on the underlying astrophysical model. The candidate line list is validated via spectral fitting with simple continuum and line profile models. We also compare the catalog content with published literature results on a small number of exemplary sources. Results. We generate a catalog of emission lines (1.2 × 104) detected in ∼1600 observations toward stars, X-ray binaries, supernovae remnants, active galactic nuclei, and groups and clusters of galaxies. For each line, we report the observed wavelength, broadening, energy and photon flux, equivalent width, and so on. [ABSTRACT FROM AUTHOR]

Cross-layer reliability is becoming the preferred solution when reliability is a concern in the design of a microprocessor-based system. Nevertheless, deciding how to distribute the error management across the different layers of the system is a very complex task that requires the support of dedicated frameworks for cross-layer reliability analysis. This paper proposes SyRA, a system-level cross-layer early reliability analysis framework for radiation induced soft errors in memory arrays of microprocessor-based systems. The framework exploits a multi-level hybrid Bayesian model to describe the target system and takes advantage of Bayesian inference to estimate different reliability metrics. SyRA implements several mechanisms and features to deal with the complexity of realistic models and implements a complete tool-chain that scales efficiently with the complexity of the system. The simulation time is significantly lower than micro-architecture level or RTL fault-injection experiments with an accuracy high enough to take effective design decisions. To demonstrate the capability of SyRA, we analyzed the reliability of a set of microprocessor-based systems characterized by different microprocessor architectures (i.e., Intel x86, ARM Cortex-A15, ARM Cortex-A9) running both the Linux operating system or bare metal in the presence of single bit upsets caused by radiation induced soft errors. Each system under analysis executes different software workloads both from benchmark suites and from real applications. [ABSTRACT FROM AUTHOR]

This paper shows the correlation of the characteristic Ne soft X-ray (SXR) signal pulse with computed dynamics of the plasma focus using doped neon in Ne (97.5%)/Kr (2.5%) admixtures. The Lee model code is coupled with a specifically designed correlation excel template. The results show that typically, the characteristic Ne SXR pulse signal starts after the start of the reflected shock (RS) and before the beginning of the pinch. Specifically, in the illustrated shot, the RS phase starts at $3.375~\mu \text{s}$ while the pinch phase starts at $3.384~\mu \text{s}$. The characteristic Ne SXR signal pulse starts at $3.377~\mu \text{s}$ , which is 2 ns after the start of the RS and 7 ns before the pinch starts. There is a consistent trend of Ne SXR correlation with the computed dynamics in the Ne doped with Kr admixtures up to a doping level of 2.5%. [ABSTRACT FROM AUTHOR]

Modelling plasma-based seeded soft X-ray lasers from the creation of the plasma to the propagation of a femtosecond high-order harmonic (HOH) seed throughout several millimetres of inhomogeneous plasma is a complex challenge. Different spatio-temporal scales from the hydrodynamic evolution of the plasma (hundreds of micrometres and nanoseconds) to the propagation of pulses through the plasma (millimetres and tens of picoseconds), electron collisions (picoseconds or even shorter) and the evolution of the envelope of the seeded HOH (tens of femtoseconds) must be tackled in order to fully understand these systems. In this paper, we will present the multi-scale computational paradigm that we have used to perform a full ab initio simulation of a dense, Ni-like Krypton plasma amplifier of soft X-rays. Results of the modelling and expected future applications will also be shown. [ABSTRACT FROM AUTHOR]