Future Facilities Research Articles

Convolutional neural networks as an alternative to Bayesian retrievals for interpreting exoplanet transmission spectra

Context. Exoplanet observations are currently analysed with Bayesian retrieval techniques to constrain physical and chemical properties of their atmospheres. Due to the computational load of the models used to analyse said observations, a compromise is usually needed between model complexity and computing time. Analyses of observational data from future facilities, such as the James Webb Space Telescope (JWST), will require more complex models, and this will increase the computational load of retrievals, prompting the search for a faster approach for interpreting exoplanet observations. Aims. Our goal is to compare machine learning retrievals of exoplanet transmission spectra with nested sampling (Bayesian retrieval) and to understand if machine learning can be as reliable as a Bayesian retrieval for a statistically significant sample of spectra while being orders of magnitude faster. Methods. We generated grids of synthetic transmission spectra and their corresponding planetary and atmospheric parameters, with one using free chemistry models and the other using equilibrium chemistry models. Each grid was subsequently rebinned to simulate both Hubble Space Telescope, Wide Field Camera 3 (WFC3), and JWST Near-InfraRed Spectrograph observations, yielding four datasets in total. Convolutional neural networks (CNNs) were trained with each of the datasets. We performed retrievals for a set of 1000 simulated observations for each combination of model type and instrument with nested sampling and machine learning. We also used both methods to perform retrievals for real WFC3 transmission spectra of 48 exoplanets. Additionally, we carried out experiments to test how robust machine learning and nested sampling are against incorrect assumptions in our models. Results. Convolutional neural networks reached a lower coefficient of determination between predicted and true values of the parameters. Neither CNNs nor nested sampling systematically reached a lower bias for all parameters. Nested sampling underestimated the uncertainty in ~8% of retrievals, whereas CNNs correctly estimated the uncertainties. When performing retrievals for real WFC3 observations, nested sampling and machine learning agreed within 2σ for ~86% of spectra. When doing retrievals with incorrect assumptions, nested sampling underestimated the uncertainty in ~12% to ~41% of cases, whereas for the CNNs this fraction always remained below ~10%.

Sensitivity of anomalous quartic gauge couplings via Zγγ production at future hadron-hadron colliders

Triple gauge boson production provides a promising opportunity to probe the anomalous quartic gauge couplings in understanding the details of electroweak symmetry breaking at future hadron-hadron collider facilities with increasing center of mass energy and luminosity. In this paper, we investigate the sensitivities of dimension-8 anomalous couplings related to the ZZγγ and Zγγγ quartic vertices, defined in the effective field theory framework, via pp→Zγγ signal process with Z-boson decaying to charged leptons at the high luminosity phase of LHC (HL-LHC) and future facilities, namely the High Energy LHC (HE-LHC) and Future Circular hadron-hadron collider (FCC-hh). We analyzed the signal and relevant backgrounds via a cut based method with Monte Carlo event sampling where the detector responses of three hadron collider facilities, the center-of-mass energies of 14, 27 and 100 TeV with integrated luminosities of 3, 15 and 30ab−1 are considered for the HL-LHC, HE-LHC and FCC-hh, respectively. The reconstructed 4-body invariant mass of l+l−γγ system is used to constrain the anomalous quartic gauge coupling parameters under the hypothesis of absence of anomalies in triple gauge couplings. Our results indicate that the sensitivity on anomalous quartic couplings fT8/Λ4 and fT9/Λ4 (fT0/Λ4, fT1/Λ4 and fT2/Λ4) at 95% C.L. for FCC-hh with Lint=30ab−1 without systematic errors is two (one) order better than the current experimental limits. Considering a realistic systematic uncertainty such as 10% from possible experimental sources, the sensitivity of all anomalous quartic couplings gets worsen by about 1.2%, 1.7% and 1.5% compared to those without systematic uncertainty for HL-LHC, HE-LHC and FCC-hh, respectively.

Understanding the concept of Industrial Tourism

Industrial Tourism can be seen as a type of tourism that includes visits to industrial sites of the present, past or future, therefore including sites that are no longer active in their industrial function, industrial companies currently in operation, sites of future industrial facilities and places whose theme is related to industry (namely industrial technology centers, museums, industrial tourist routes, schools, and industrial laboratories). Thus, Industrial Tourism can include all kinds of tourist activities whose main reason for the visit is related to industrial knowledge, material and/or immaterial heritage. However, there is still a lack of conceptual clariry in the literature that may preclude the affirmation of this research topic that has received a reduced, but increasing, attention from the tourism studies community. The paper aims to contribut to a better understanding of the concept of Industrial Tourism and how it has evolved over time. For that it performs a systematic literature review considering 86 papers published in journals indexed in the two major bibliographic bases - Scopus and Web of Science, between 1996 and 2021. The analysis shows the heterogeneity of definition and approachs to this type of tourism. It also identifies two main approaches to the study of Industrial Tourism. The first sees the tourism phenomenon through the use of elements from the industrial past; The second, adresses it through the visit to active industries, which will allow tourists to experience firsthand the production processes of the products they consume.

Repurposing and the Impact of New Facilities on the Potential Presentation of Industrial Heritage

Industrial heritage combines historical, architectural and cultural values of the context in which it is located. In order for the spatial and architectural potential of these buildings to be used even after the loss of their initial purpose, the previous plants become the hub of new activity through repurposing and adjustment. This study is focused on the interpolation of hotel and business/trade activities within the previous industrial complex Belgrade “Steam Mill” where the practical issues related to the implementation of this entire process have been presented by means of a detailed analysis (case study). Repurposing of the old plant has been accepted as an evolutionary model of integrative protection. This paper names the shifts in the social and economic context of ex-Yugoslavia and adoption of new economic and cultural patterns as one of the causes for the abandonment of the Mill and its fall into disrepair. Accordingly, the contribution of this paper is based on an overview of a potential identification of a specific model for future actions in similar situations and in relation to the industrial heritage of the Republic of Serbia. The critical analysis of the results of Steam Mill repurposing presented in this paper implies the reviewing of both positive and negative aspects of the said process with the aim of understanding the significance of appropriate planning and use of future facilities in relation to the protection and promotion of cultural heritage values of general interest.

The Detection of GRBs at VHE: A Challenge Lasting for More than Two Decades, What Is Next?

Unveiling the mystery of gamma-ray bursts (GRBs) has been the target of many multi-waveband observational and theoretical efforts during the last decades. The results collected by current and past space-based instruments have provided important insights into the mechanisms at the origin of their prompt and afterglow phases. On the other hand, many questions, such as the the origin of the multi-GeV signal observed in a large number of events, remained unanswered. Within this framework, the first firm detections of a very-high-energy (VHE, E≳100 GeV) emission component by MAGIC and H.E.S.S. collaborations represented an important, long-awaited result for the VHE astrophysics community. However, while such discoveries opened a new era in the study of GRBs, they also provided an unexpected complexity due to the differences between the phenomenology of the observed events. This revealed that we still have an incomplete comprehension of GRB physics. In the nearby future, observations by the Cherenkov Telescope Array Observatory (CTAO), with unprecedented sensitivity in the VHE band, will have a key role in the study of these enigmatic objects and their interactions with the surrounding environment. In this review we will cover the recent GRB history, highlighting the efforts of follow-up campaigns by the VHE community that led to the first VHE GRB detection, and outlining what we can expect from future facilities in the next decades.

Difficulties of healthcare workers encountered under cohort isolation in a psychiatric hospital during the COVID-19 pandemic: A qualitative study

This study examined the experiences of healthcare workers who were quarantined within the psychiatric wards due to COVID-19 and analyzed those experiences with a consensual qualitative research method. Participants experienced (a) difficulties due to the specificity of a mental hospital, including a lack of protocols, noncompliance with quarantine guidelines among patients with severe mental illness, and a shortage of institutions capable of containing confirmed COVID-19 patients with severe mental illness. Furthermore, (b) difficulties related to isolation of the cohort itself included a workforce shortage, physical problems, fear of infection, limited facilities, guilt toward newly confirmed cases, exhaustion, and distress caused by separation from family. The participants also described (c) difficulties related to external factors, including administrative orders and the perceived stigma, and (d) positive experiences. Appropriate support is needed during the COVID-19 pandemic to reduce the difficulties among healthcare workers in psychiatric hospitals. This includes preparation for future scenarios, facilities, and workers in response to outbreaks of infection in psychiatric hospitals that cause unique risks and challenges among those workers.

Expert perspectives on the wind plant of the future

AbstractWind power technology has changed rapidly in recent years. Technology innovation, evolving power markets, and competing land and ocean uses continue to influence the design and operation of wind turbines and plants. Anticipating these trends and their impact on future facilities can inform commercial strategies and research priorities. Drawing from a recent survey of 140 of the world's foremost wind experts, we identify expectations of future wind plant design in 2035, both for onshore and offshore wind. Experts anticipate continued growth in turbine size, to 5.5 (onshore) and 17 MW (offshore), with plants located in increasingly less favorable wind and siting regimes. They expect plant sizes of 1,100 MW for fixed‐bottom and 600 MW for floating offshore wind. Experts forecast enhanced grid‐system value from wind through significant to widespread use of larger rotors, hybrid projects with batteries and hydrogen production, and more. To explain experts' perspectives on future plant design and operation, we identify five mechanisms: economies of unit, plant, and resource scale; grid‐system value economies; and production efficiencies. We characterize learning effects as a moderating influence on the strength of these mechanisms. In combination, experts predict that these design choices support levelized cost of energy reductions of 27% (onshore) and 17%–35% (floating and fixed‐bottom offshore) by 2035 compared to today, while enhancing wind energy's grid service offerings. Our findings provide a much‐needed benchmark for representing future wind technologies in power sector models and address a critical research gap by explaining the economics behind wind energy design choices.

Simulation study of gamma-ray spectroscopy on MYRRHA spent fuel located in lead–bismuth eutectic

A concept model of a measurement station for gamma-ray spectroscopy for safeguards verification of spent fuel from the future MYRRHA facility has been developed using MCNP6.2. The measurement station consists of a collimator and a lanthanum bromide detector which are placed adjacent to a cylindrical container with the fuel assembly submerged in lead–bismuth eutectic for cooling. The total count rate as well as the peak-area uncertainties for several gamma-ray peaks have been studied for a number of measurement geometries to determine the optimal collimator dimensions and assess how the performance depends on the lead–bismuth container geometry. Finally, the contribution from each fuel pin in the assembly to the detected signal has been determined as a function of gamma-ray energy to determine if the inner parts of the fuel assembly can be assayed with gamma-ray measurements. The results show that the dimensions of the lead–bismuth container will have a considerable effect on both the total count rate and the peak-area uncertainties, but that gamma-ray spectroscopy could be used for verification of spent fuel from MYRRHA.

Monitoring of Ultra-High Dose Rate Pulsed X-ray Facilities with Radioluminescent Nitrogen-Doped Optical Fiber.

We exploited the potential of radiation-induced emissions (RIEs) in the visible domain of a nitrogen-doped, silica-based, multimode optical fiber to monitor the very high dose rates associated with experiments at different pulsed X-ray facilities. We also tested this sensor at lower dose rates associated with steady-state X-ray irradiation machines (up to 100 keV photon energy, mean energy of 40 keV). For transient exposures, dedicated experimental campaigns were performed at ELSA (Electron et Laser, Source X et Applications) and ASTERIX facilities from CEA (Commissariat à l’Energie Atomique—France) to characterize the RIE of this fiber when exposed to X-ray pulses with durations of a few µs or ns. These facilities provide very large dose rates: in the order of MGy(SiO2)/s for the ELSA facility (up to 19 MeV photon energy) and GGy(SiO2)/s for the ASTERIX facility (up to 1 MeV). In both cases, the RIE intensities, mostly explained by the fiber radioluminescence (RIL) around 550 nm, with a contribution from Cerenkov at higher fluxes, linearly depend on the dose rates normalized to the pulse duration delivered by the facilities. By comparing these high dose rate results and those acquired under low-dose rate steady-state X-rays (only RIL was present), we showed that the RIE of this multimode optical fiber linearly depends on the dose rate over an ultra-wide dose rate range from 10−2 Gy(SiO2)/s to a few 109 Gy(SiO2)/s and photons with energy in the range from 40 keV to 19 MeV. These results demonstrate the high potential of this class of radiation monitors for beam monitoring at very high dose rates in a very large variety of facilities as future FLASH therapy facilities.

Revisiting constraints on asymmetric dark matter from collapse in white dwarf stars

The runaway collapse phase of a small dark matter cluster inside a white dwarf star encompasses a reversible stage, where heat can be transferred back and forth between nuclear and dark matter. Induced nuclear burning phases are stable and early carbon depletion undermines previous claims of type Ia supernova ignition. Instead, mini black holes are formed at the center of the star that either evaporate or accrete stellar material until a macroscopic sub-Chandrasekhar-mass black hole is formed. In the latter case, a 0.1 to 1 second lasting electromagnetic transient signal can be detected upon ejection of the white dwarf's potential magnetic field. Binary systems that transmute to black holes and subsequently merge emit gravitational waves. Advanced LIGO should detect one such sub-Chandrasekhar binary black hole inspiral per year, while future Einstein telescope-like facilities will detect thousands per year. The effective spin parameter distribution is peaked at 0.2 and permits future studies to disentangle from primordial sub-Chandrasekhar black holes. Such signatures are compatible with current direct detection constraints, as well as with neutron star constraints in the case of bosonic dark matter, even though they remain in conflict with the fermionic case for part of the parameter space.

ADVANTAGES AND CONSTRAINTS OF SPECIFIC AUTOCAD PLANT 3D FUNCTIONS FOR DYNAMIC MANAGEMENT - CASE STUDY FOR A HEAVY WATER DETRITIATION INSTALLATION AT CERNAVODA N.P.P.

The advantages and constraints of the specific Autocad Plant 3D functions for dynamic management - production of technological diagrams, isometrics, orthogonal views, bills of materials and piping system erection projects for the future detritiation facility at the Cernavodă Nuclear Power Plant (Cernavoda N.P.P.) are presented in a case study. In last decades 3D modelling of the plant has been increasing used in design of new projects in nuclear power plant (NPP) both in design period but also in design changes required during life time and extended life time of a plant. In the proposed case we developed a model to make an engineering design application for plant design incorporating disciplines such as piping, piping support, equipment, civil and steel structure. Using 3D Plant capabilities we can improve design process, interdisciplinary check-out as well as project execution. The project could be updated after as built revision of isometric drawings in order to obtain a training model for the system to prepare plant operators to make scheduled and unscheduled maintenance and time estimation of different maintenance procedures that could be required during plant operation in order to reduce as low as reasonable possible dose received during detritiation installation maintenance.

Feasibility study of D_s^+ rightarrow tau ^+ nu _{tau } decay and test of lepton flavor universality with leptonic D_s^+ decays at STCF

We report a sensitive study of D_s^+ rightarrow tau ^+ nu _{tau } decay via tau ^+ rightarrow e^+ nu _e bar{nu }_{tau } with an integrated luminosity of 1 ab^{-1} at the center-of-mass energy of 4.009 GeV at a future Super Tau Charm Facility (STCF). Under the help of the fast simulation software package, the statistical sensitivity for the absolute branching fraction of D_s^+ rightarrow tau ^+ nu _{tau } is determined to be 2times 10^{-4}. Combining with our previous prospect of D_s^+ rightarrow mu ^+ nu _{mu }, the ratio of the branching fractions for D_s^+ rightarrow tau ^+ nu _{tau } over D_s^+ rightarrow mu ^+ nu _{mu } can achieve a relative statistical precision of 0.5%, which will provide the most stringent test of the tau -mu lepton flavor universality in heavy quark decays. Taking the decay constant f_{D_s^+} from lattice QCD calculations or the CKM matrix element |V_{cs}| from the CKMfitter group as an input, the relative statistical uncertainties for |V_{cs}| and f_{D_s^+} are estimated to be 0.3% and 0.2%, respectively.

Negative hydrogen ion sources for particle accelerators: Sustainability issues and recent improvements in long-term operations

High brightness, negative hydrogen ion sources are used extensively in scientific facilities operating worldwide. Negative hydrogen beams have become the preferred means of filling circular accelerators and storage rings as well as enabling efficient extraction from cyclotrons. Several well-known facilities now have considerable experience with operating a variety of sources such as RF-, filament-, magnetron- and Penning-type H- ion sources. These facilities include the US Spallation Neutron Source (SNS), Japan Proton Accelerator Research Complex (J-PARC), Rutherford Appleton Laboratory (RAL-ISIS), Los Alamos Neutron Science Center (LANSCE), Fermi National Accelerator Laboratory (FNAL), Brookhaven National Laboratory (BNL), numerous installations of D-Pace (licenced by TRIUMF) ion sources used mainly on cyclotrons and, most recently, the CERN-LINAC-1 injector. This report first summarizes the current performance of these ion sources in routine, daily operations with attention toward source service-periods and availability metrics. Sustainability issues encountered at each facility are also reported and categorized to identify areas of common concern and key issues. Recent ion source improvements to address these issues are also discussed as well as plans for meeting future facility upgrade requirements.

Relation of migration trend and gender of RMG labour force in Industrial areas in Bangladesh

Legitimate labour migration has, no doubt, got much attention in various economies and labour force irrespective of gender tempt for diverse employment. Industrial employment and job concentration in industrial cluster always provoke work driven migration. People relocate their whereabouts based on their secure livelihoods. And, economic centralization and targeted migration thus associate each other with no exception in Bangladesh. In the 5-decade long industrial history, many changes, reforms and challenges were noticed throughout our industrial ecosystem and labour dynamics. Labour force is a critical strength for efficient and low-cost productivity. In this regard, our mixed labour force, skilled, semi and unskilled workforce, has shaped our local industry and positioned as the most competitive regionally and contributed to gain productivity momentum and foreign trade growth. RMG industry, the forefront export-oriented sector of economy, has emerged as the largest employer of local migrated workforce of all contemporary industries in Bangladesh encouraging labour migration in urban area. This industry shares relatively large in GDP and export earning. With unprecedented contribution by RMG to economy, this study attempted to know whether any relationship of migration trend and gender status since this industry is a female dominant industry. The assessment of correlation is justifiably demanded due to women employment intensity since inception. But, this quantitative research-cause and effect study resulted that gender and migration condition and flow have no positive relationship and integration upon applying non-parametric test Chi-square test of significance. Around 252 independent samples from RMG factories in Dhaka and nearby districts where industrial hubs are located. It has obtained the null and rejected alternative hypothesis. These findings may help for national perspective planning and development planning. The drawn outcomes may also enable us national resource planning, mapping and human development index. As well, we can measure labour productivity in RMG industry and plan for future facility as well urban living and economic development.

High voltage dc gun for high intensity polarized electron source

The high intensity polarized electron source is a critical component for future nuclear physics facilities. The Electron Ion Collider (EIC) requires a polarized electron gun with higher voltage and higher bunch charge compared to any existing polarized electron source. At Brookhaven National Laboratory, we have built an inverted high voltage direct current (HVDC) photoemission gun with a large cathode size. We report on the performances of GaAs photocathodes in a high gradient with up to a 16 nC bunch charge. The measurements were performed at a stable operating gap voltage of 300 kV - demonstrating outstanding lifetime, and robustness. We observed obvious lifetime enhancement by biasing the anode. The gun also integrated a cathode cooling system for potential application on high current electron sources. The various novel features implemented and demonstrated in this polarized HVDC gun open the door towards future high intensity-high average current electron accelerator facilities.

Giant Planet Atmospheres: Dynamics and Variability from UV to Near-IR Hubble and Adaptive Optics Imaging

Each of the giant planets, Jupiter, Saturn, Uranus, and Neptune, has been observed by at least one robotic spacecraft mission. However, these missions are infrequent; Uranus and Neptune have only had a single flyby by Voyager 2. The Hubble Space Telescope, particularly the Wide Field Camera 3 (WFC3) and Advanced Camera for Surveys (ACS) instruments, and large ground-based telescopes with adaptive optics systems have enabled high-spatial-resolution imaging at a higher cadence, and over a longer time, than can be achieved with targeted missions to these worlds. These facilities offer a powerful combination of high spatial resolution, often <0.05”, and broad wavelength coverage, from the ultraviolet through the near infrared, resulting in compelling studies of the clouds, winds, and atmospheric vertical structure. This coverage allows comparisons of atmospheric properties between the planets, as well as in different regions across each planet. Temporal variations in winds, cloud structure, and color over timescales of days to years have been measured for all four planets. With several decades of data already obtained, we can now begin to investigate seasonal influences on dynamics and aerosol properties, despite orbital periods ranging from 12 to 165 years. Future facilities will enable even greater spatial resolution and, combined with our existing long record of data, will continue to advance our understanding of atmospheric evolution on the giant planets.

Roadmap to hydrogen society of Tokyo: Locating priority of hydrogen facilities based on multiple big data fusion

Hydrogen socialization has become a promising target in future energy development. Hydrogen fuel cell vehicle is gradually becoming a considerable substitute for fossil fuel vehicles in many countries. As for the promotion of hydrogen fuel cell vehicles, The construction of facilities like hydrogen refueling stations and depots should be strengthened. The research provides a case study of locating the priority of the construction of hydrogenation facilities, based on policy regulation, massive GPS trajectory records, geographical land use data, road network and, POI data. The PageRank value in the complex network theory is employed to estimate the priority of the Land use Unit and policies regulation is referred to to ensure the feasibility of construction. Among 24,595 Land Use Units in sum, 59.78% of them are allowed to build hydrogen facilities. The results show that the available location of hydrogen refueling stations with high priority (we pick the first 100 for analysis) and feasibility in policy are geographically clustered around the city centers and sub-centers. The place with the highest PageRank value of 0.0033 is Haneda airport, which is an important transportation hub. The PageRank values of most of the other first 100 ranked Land Use Units are under 0.001. This indicates that the vehicle transportation network is highly centralized. There is an obvious sequence of priority of hydrogen refueling stations. We furtherly provide sensitivity analysis and it shows that higher-ranked places are spatially clustered. The best hydrogen depot is located near Tokyo Bay with the advantage of low transportation cost of liquid hydrogen, convenient transportation conditions, strong safety assurance. After verification, the results showed consistency with the current hydrogenation facility construction process and demonstrated the potential for future hydrogenation facility construction.

Applying ALARA Principles in the Design of New Radiological Facilities.

The application of ALARA (as low as reasonably achievable) principles to the design of new radiological facilities at Argonne National Laboratory provides a consistent radiation safety basis for future facility operations. This paper discusses the criteria for controlling radiation exposure and the techniques applied to meet those criteria for two new facilities. Argonne is a US Department of Energy (US DOE) laboratory, and the criteria are specified in the DOE Rule found at 10 CFR 835. The worst case radionuclides and their source strengths are chosen. Local shielding is specified to reduce dose rates to less than 50 μSv h-1at 30 cm from the shielding, thus avoiding the creation of a radiation area. Version 6 of the Los Alamos National Laboratory radiation transport code MCNP is then used to calculate the dose rates elsewhere. Based on the results of the calculations, design modifications are made to meet the design objectives criteria.

High star cluster formation efficiency in the strongly lensed Sunburst Lyman-continuum galaxy at z = 2.37

We investigate the strongly lensed (μ ≃ ×10 − 100) Lyman continuum (LyC) galaxy, dubbed Sunburst, at z = 2.37, taking advantage of a new accurate model of the lens. A characterization of the intrinsic (delensed) properties of the system yields a size of ≃3 sq. kpc, a luminosity of MUV = −20.3, and a stellar mass of M ≃ 109 M⊙; 16% of the ultraviolet light is located in a 3 Myr old gravitationally bound young massive star cluster (YMC), with an effective radius of ∼8 pc (corresponding to 1 milliarcsec without lensing) and a dynamical mass of ∼107 M⊙ (similar to the stellar mass) – from which LyC radiation is detected (λ < 912 Å). The star formation rate and stellar mass surface densities for the YMC are Log10(ΣSFR[M⊙ yr−1 kpc−2]) ≃ 3.7 and Log10(ΣM[M⊙ pc−2]) ≃ 4.1, with sSFR > 330 Gyr−1, consistent with the values observed in local young massive star clusters. The inferred outflowing gas velocity (> 300 km s−1) exceeds the escape velocity of the cluster. The resulting relative escape fraction of the ionizing radiation emerging from the entire galaxy is higher than 6−12%, whilst it is ≳46 − 93% if inferred from the YMC multiple line of sights. At least 12 additional unresolved star-forming knots with radii spanning the interval 3 − 20 pc (the majority of them likely gravitationally bound star clusters) are identified in the galaxy. A significant fraction (40−60%) of the ultraviolet light of the entire galaxy is located in such bound star clusters. In adopting a formation timescale of the star clusters of 20 Myr, a cluster formation efficiency Γ ≳ 30%. The star formation rate surface density of the Sunburst galaxy (Log10(ΣSFR) = 0.5−0.2+0.3) is consistent with the high inferred Γ, as observed in local galaxies experiencing extreme gas physical conditions. Overall, the presence of a bursty event (i.e., the 3 Myr old YMC with large sSFR) significantly influences the morphology (nucleation), photometry (photometric jumps), and spectroscopic output (nebular emission) of the entire galaxy. Without lensing magnification, the YMC would be associated to an unresolved 0.5 kpc–size star-forming clump. The delensed LyC and UV magnitude m1600 (at 1600 Å) of the YMC are ≃30.6 and ≃26.9, whilst the entire galaxy has m1600 ≃ 24.8. The Sunburst galaxy shows a relatively large rest-frame equivalent width of EWrest(Hβ + [O III]λλ4959, 5007) ≃ 450 Å, with the YMC contributing to ∼30% (having a local EWrest ≃ 1100 Å) and ∼1% of the total stellar mass. If O-type (ionizing) stars are mainly forged in star clusters, then such engines were the key ionizing agents during reionization and the increasing occurrence of high equivalent width lines (Hβ + [O III]) observed at z > 6.5 might be an indirect signature of a high frequency of forming massive star clusters (or high Γ) at reionization. Future facilities, which will perform at few tens milliarcsec resolution (e.g., VLT/MAVIS or ELT), will probe bound clusters on moderately magnified (μ < 5 − 10) galaxies across cosmic epochs up to reionization.

On the equivalence of irradiation conditions on present and future facilities for fusion materials research and qualification: A computational study

We performed a computational study to assess the suitability and equivalence of the irradiation conditions on several test irradiation facilities (either currently operating or planned to deploy in the future) aimed at the qualification of materials for nuclear fusion reactors such as ITER and DEMO. The degradation of the material's properties is driven by the changes in its microstructure and chemistry (transmutation). The primary objective of this study is thus to perform a comparison of the microstructural pattern as predicted by means of simulations. The focus of the study is put on two materials: Eurofer97 steels and tungsten. We considered operation conditions in fusion reactors (i.e. ITER and DEMO) and in test irradiation facilities such as material test reactors (fast and mixed neutron spectrum), IFIMIF-DONES, ESS and proton accelerators. Typical irradiation conditions are addressed according to the currently available design (for DEMO) and expected operation modes (for ITER). The study is realized by means of object kinetic Monte Carlo which is parameterized and configured using state-of-the-art knowledge on irradiation spectra, neutron cross-sections, primary damage states, lattice defects mobility/cohesion and interaction of the material's microstructure with lattice defects. The irradiation defects are singled out using a dedicated post-processing tools to enable a comparison with expected findings in transmission electron microscopy (TEM) and atom probe tomography (APT). The results are discussed in terms of the equivalence of the emerging irradiation microstructure predicted to occur in test irradiation facilities if compared with the one simulated in the nuclear fusion reactors. The summary and discussion provide information on the equivalence and deviations of the microstructural patterns suggesting the suitability of the test irradiation facilities for certain irradiation regimes, as well as pointing at some limitations, e.g., originating from the difference in the neutron spectra or flux.