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The SuperCDMS experiment: Status and prospects
No full textThe Super Cryogenic Dark Matter Search (SuperCDMS) experiment is one of the leading role actors in the search for Dark Matter (DM), focusing on particles with masses below 10 GeV/c2. After its successful campaign in the Soudan
Underground Laboratory, the project is preparing for its next phase moving to the SNOLAB laboratory in Sudbury, Canada. Improved detector technologies and the new experiment set-up will allow to push the sensitivity to lower masses, down to about 0.5 GeV/c2 for Weakly Interacting Massive Particles (WIMPs) and to improve
the cross-section reach by more than one order of magnitude. One key ingredient for the experiment’s success is the precise knowledge of the ionization yield in silicon (Si) and germanium (Ge) at low energy. This manuscript, after briefly describing the SuperCDMS status and prospects, reports the measurement of the ionization yield in Ge performed by the collaboration using data from the previous campaign in Soudan
First education in the fundamentals of figurative thinking in physics
Get PDFThis paper presents the theoretical and practical developments of research in physics education carried out at Free University of Bozen-Bolzano, which focuses mainly on primary physical science education. Our research is characterized by a move toward integrating the discipline and its didactics with the humanities to properly consider the human component of education. Both qualitative and
quantitative outcomes, especially relating to prospective teachers’ education, will be presented. Moreover, the main national and international projects that have been completed or are still active at Free University of Bozen-Bolzano will be briefly outlined
Learning progressions: An overview and how-to guide for researchers in physics education
Get PDFLearning progressions are a well established model in science edu-cation research to represent the learning process. It lies at the heart of the learning progressions the idea that students develop their knowledge of a subject from na¨ıve conceptions and, through a series of intermediate stages of increasingly sophisticated
understanding, come to master a scientifically correct body of knowledge. Starting from a learning progression, it is possible to develop entire curricula and large-scale
evaluation tools based on empirical data. We will present a review of the literature on learning progressions and discuss possible implications for research in physics
education and teaching practice
History teaches: Some educational projects based on the history of physics
Get PDFWe present some projects carried out in recent years and aimed at students of different levels (from high school to university), where we have adopted well-defined historical paths. The basic aim is to allow the students involved to
develop appropriate physical reasoning skills, without the preventive request of a good standard preparation of the topics covered. The lines of action which were common to the various projects were intended to encourage the students to: 1) think like the given scientist of the past who is the object of the project, building step by step proper knowledge and reasoning; 2) work like that scientist, performing the original experiments; 3) deduce just as that scientist did concerning the subject matter; 4) present the results of their activity (including Physics demonstrations)
to other students and, in general, to the general public, in order to test their ability to communicate what they have learned and discovered. These educational goals have always been accompanied by the desire to carry out historically consistent activities, based on the awareness of the key role that the history of physics can play in promoting scientific understanding at a deep level, even without requiring particular mathematical knowledge or advanced preparation. The enthusiasm of the students involved in the various projects, especially in demonstrating the result of
their work to other students or in public events, as well as the prompt involvement of the aforementioned public (lacking adequate preparation or specific knowledge in the proposed activity), undoubtedly testify in favor of the success of the work presented here
Passive methods for spent fuel characterisation at the Finnish geological repository
Get PDFDevelopment of the Passive Gamma Emission Tomography (PGET) and Passive Neutron Albedo Reactivity (PNAR) methods in the context of the Finnish geological repository for spent nuclear fuel has shown that they provide, for BWR fuel assemblies, the comprehensive verification needed to meet the nuclear safeguards objectives of the repository. The principles of the PGET and PNAR methods and the design and operation of the respective instruments are presented. A few results from measurements at the spent fuel storage pools at the Finnish nuclear power plants are discussed. The directions of ongoing and future developments are indicated
Measuring μB at the LHC with ALICE via antiparticle-over-particle ratios
Get PDFThe baryon chemical potential μB is a fundamental parameter for the statistical mechanical description of particle production in heavy-ion collisions: its value encodes the average net baryon content of the fireball at chemical freeze-out. The first μB measurement in high-energy Pb-Pb collisions at the LHC was published in 2018 in Nature, and it was found that μB = 0.7 ± 3.8 MeV. In this contribution,
an improved μB measurement based on the study of antiparticle-to-particle ratios for protons, 3He and hypertriton (3ΛH) using the data collected by ALICE in Run 2
of the LHC, is presented. The isospin chemical potential is also determined via the π−/π+ ratio. The obtained μB represents the most precise measurement available
The KAMEO proposal: Investigation of the E2 nuclear resonance effects in kaonic atoms
Get PDFThe E2 nuclear resonance effect is a phenomenon that occurs when the energy of an atomic de-excitation state closely matches that of a nuclear excitation state, resulting in the attenuation of certain atomic X-ray lines in the resonant
isotope target. The study of this effect in kaonic atoms can provide important insight into the mechanisms of the strong kaon-nucleus interaction. In 1975, Goldfrey, Lum, and Wiegand at Lawrence Berkeley Laboratory observed the effect in 98 42Mo, but they did not have enough data to reach a conclusive result. The E2 nuclear resonance effect is expected to occur in four kaonic molybdenum isotopes (94
42Mo, 96 42Mo, 98 42Mo, and 100 42 Mo) with similar energy values. The KAMEO (Kaonic Atoms Measuring Nuclear Resonance Effects Observables) proposal plans to study this effect in these isotopes at the DAΦNE Φ factory during the SIDDHARTA-2 experiment. KAMEO will use four solid strip targets, each enriched with a different molybdenum isotope, and expose them to negatively charged kaons produced by Φ meson decays. The X-ray transition measurements will be performed using a high-purity germanium detector, and an additional solid strip target of non-resonant 92 42Mo isotope will be
exposed and used as a reference for standard non-resonant transitions
Low-contrast detection and super-resolution in CT images: Evaluation of a novel approach based on Centroidal Voronoi Tessellation
Get PDFIn this work, image analysis techniques used in astrophysics to detect low-contrast signals have been adapted in the processing of Computed Tomography (CT) images, combining Centroidal Voronoi Tessellation (CVT) and machine learn-
ing techniques. Several CT acquisitions were performed using a phantom containing cylindrical inserts of different diameters producing objects with different contrasts with respect to the background. The images of the phantom, tilted by a known angle with respect to the tomograph axis (to mimic the casual orientation of a clinical lesion), were acquired at various radiation doses (CT DIvol) and at different slice’s thicknesses. The success in detecting the signal in the single image (slice) was always greater than 60%. The axis of each insert has always been correctly identified. A super-resolution 2D image was then generated by projecting the individual slices of the scan along this axis, thus increasing the CNR of the object scanned as a whole. CVT holds great promise for future use in medical imaging, for the identification of low-contrast lesions in homogeneous organs, such as the liver
Triple Parton Scattering at the Compact Muon Solenoid experiment
Get PDFIn 2021, the CMS Collaboration observed a triple J/ψ production
from the same event: the result excited large interest in Triple Parton Scattering (TPS) in proton-proton interactions. This has driven us to investigate a new
charmed final state with two J//w and a D* in the CMS experimental framework. The preliminary work that lays the foundation for a complete analysis will be discussed here
Characterization of new photomultipliers and fibers for the LUCID-3 prototypes for HL-LHC
Get PDFLUCID-2, the main luminometer of the ATLAS experiment, guaranteed a precision of 1% and a time stability of about 1% during LHC Run-2. Similar performances are expected for Run-3 as well. Due to the higher pile-up and radiation
damage, a new LUCID is needed to fulfill the requirements of Run-4. New photomultipliers (PMTs) and fibers have been installed in ATLAS as LUCID-3 prototypes and are evaluated for their use in Run-4. The first results of this characterization campaign are presented. The newly proposed PMTs generate shorter signals compared to LUCID-2 PMTs and the current readout system is not able to digitize them optimally. A fiber irradiation session was performed to estimate the radiation damage during Run-4. A larger loss was observed in the UV region with respect to the visible region, leading to a modification of the fiber prototype installed