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Characterization of the Mini-X2 X-ray Tube and sensitivity measurements of a Triple-GEM
Get PDFThe study involves the detailed characterization of an X-ray
source (Mini-X2 X-ray Tube) and the photon sensitivity measurements of a Triple Gas Electron Multiplier detector (GEM). In parallel to the experimental measurements, simulations were carried out with the GEANT4 Monte Carlo pack
age (https://geant4.web.com.ch/) both to create a shielding that would allow safe operation and for a theoretical comparison of the sensitivity measurements
The ``Yes, Magellanic Clouds Again'' survey: Preliminary results
Get PDFWe present preliminary findings from the photometric survey “Yes, Magellanic Clouds Again” (YMCA, PI: V. Ripepi), covering 110 square degrees in the outer regions of the Magellanic Clouds (MCs), a pair of interacting galaxies and the most massive dwarf satellites of the Milky Way. Among the key results, we discovered four star clusters (SCs) within the Large Magellanic Cloud (LMC) exhibiting ages within the so-called “age gap”, a period deemed so far devoid of SCs. Additionally, we unveiled an ancient stellar system associated with the LMC, featuring structural properties in between the globular clusters and the ultra-faint dwarf galaxies of the Local Group. These discoveries significantly contribute to our understanding of the MCs’ evolution and their complex interaction history
How artificial intelligence can enhance monitoring of volcanoes from space
Get PDFThe ability to collect and analyze satellite data in near real-time (NRT) is fundamental for monitoring volcanic hazards and identifying the needed mitigation actions. This capability depends mainly on the availability of satellite
data, which can range from a few minutes (SEVIRI, MODIS) to several days (MSI, OLI). Volcanology has embraced artificial intelligence (AI), incorporating both Machine Learning (ML) and Deep Learning (DL), allowing computers to learn from
historical data and build a knowledge base of volcanic processes. An AI-based platform has been developed for NRT monitoring of volcanic activity, utilizing satellite imagery and offline analysis. ML and DL algorithms automatically evaluate volcano status from extensive multi-spectral satellite data flows. Built-in modules work together towards a common goal and are activated based on AI logic. These modules are adept at diverse tasks, from forecasting eruption initiation to quantifying erupted products using satellite thermal measurements. This platform represents an
unprecedented convergence between technological innovation and the scientific community’s experience overcoming limitations of traditional approaches by inferring knowledge from large amounts of heterogeneous satellite data. It enables informed, timely, and sophisticated management of volcanic activity, significantly contributing to enhancing safety measures and minimizing the impact of volcanic events on communities and infrastructure
Studying an orphan disease by a biophysical approach: The case of cblC
Get PDFA rare disease, as defined by the European Union, is one that affects fewer than 5 persons per 10000, predominantly children. These conditions often lack effective treatments and are considered orphan diseases. Despite their rarity,
there are numerous rare diseases, sharing origin and common underlying molecular mechanisms. Focusing on the metabolic rare disease cblC, we demonstrate how an approach based on biophysical methods, can pave the way for exploring novel
treatment avenues for such conditions
Visual acuity and contrast sensitivity under monochromatic yellow light
Get PDFThis study investigates the impact of monochromatic lighting on visual acuity (VA) and contrast sensitivity (CS). Traditional assessments of VA and CS are typically conducted under the illumination of “white” light, but variations in color temperature can influence outcomes. Utilizing data from an exhibition by Olafur Eliasson, where a room was illuminated with low-pressure sodium lamps, creating an almost monochromatic yellow light, we compared visual assessments in the yellow room with conventional lighting in a white room. For VA, the results show no significant differences between the two lighting conditions, while for CS, a more nuanced situation is observed. The bias in CS measurements is clinically relevant, and the p-value suggests that further investigation with a larger, more diverse sample may be worthwhile. Despite limitations, such as higher illumination conditions than standard protocols, the unique “laboratory” offered by the exhibition facilitated measurements not easily achievable in a traditional setting
Optimizing hybrid images for an easy screening of the visual acuity
Get PDFThe development of a hybrid image (HI) is a method to create a single illusive picture, merging two images with different content in terms of spatial frequencies. Recently such a kind of optical illusion has also been used in the research area of optometry and psychology. Our study is based on the most famous HI, “Einstein-Marilyn face”, created in 2007 for the “New Scientist” magazine. This study aims to observe the role of the spatial frequencies in the interpretation of a HI in function of the visual acuity. The results show that a correct selection of the cut-off frequencies is fundamental to generating an optimal HI, i.e., with an optical illusion characterized by a non-ambiguous and stable interpretation. The design of working HIs can open the way for new kinds of tests in the field of optometry, in particular for the screening of myopia
Upper secondary school students conceptual learning of optical spectroscopy
Get PDFA Teaching Intervention Module (TIM) on optical spectroscopy was designed in the theoretical framework of the Model of Educational Reconstruction. This study illustrates a proposal for a conceptual survey related to the TIM
implemented in three classes of N = 60 high school students (18–19 years old). We focused the survey on the nature of colors and the interpretation of spectra. The data analysis was carried out through answers’ categorization. The results show that the students acquired a good knowledge about the mechanism of spectra formation, but some aspects related to atomic emission (e.g., ionization process) would need more clarification
Study of the isoscalar giant monopole resonance: Discrepancies between available experimental results
Get PDFOver the last four decades, the isoscalar giant monopole resonance
(ISGMR) was extensively studied worldwide, especially at the Texas A&M University (TAMU) Cyclotron Institute, the Research Center for Nuclear Physics (RCNP) and recently at the iThemba Laboratory for Accelerator Based Sciences (iThemba◦LABS), South Africa, through small angle (including 0 ) inelastic α-scattering mea- surements at 240, 386, and 196 MeV, respectively. In all the available datasets pub- lished by the different facilies, noticeable differences in the isoscalar giant monopole (IS0) strength distributions were observed. This paper focuses only on the two ex- treme cases: the light deformed 24Mg and the heavy spherical 208Pb to summarize discrepancies between the different results
Isoscalar giant monopole resonance in Mo-100: TDHF calculations and ground state deformation
Get PDFThe isoscalar giant monopole resonance in molybdenum-100 has been measured in recent alpha scattering experiments and its strength function extracted. By performing time-dependent Hartree-Fock calculations with Skyrme effective interactions, we are able to reproduce the gross features of the observed strength. The details of the structure are found to be dependent on the ground state shape. We use a measure of fit to determine which ground state shape correlates with the observed strength and find evidence for triaxiality in this nucleus
Systematic investigation of the Pygmy Dipole Resonance near the magic N=82 shell closure
Get PDFThe Pygmy Dipole Resonance is part of the electric dipole response of an atomic nucleus. There are still several open questions concerning, e.g., its structure. Systematic studies are crucial to improve the knowledge of this excitation mode. Such systematic studies have already been performed along the magic N = 82 isotonic chain using the Nuclear Resonance Fluorescence (NRF) technique, hinting to a trend of increasing strength with increasing N/Z ratio. Comparing these results to those from further NRF experiments on neighbouring non-magic isotopes and on 142Ce, a more fragmented strength distribution seems to occur