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Studio dei radionuclidi prodotti al reattore LENA per il progetto ISOLPHARM EIRA
Get PDFIl progetto multidisciplinare ISOLPHARM, di cui fa parte l’esperimento in cui si colloca il lavoro
di tesi, ossia ISOLPHARM EIRA, verte principalmente sullo studio di nuovi metodi per la produzione di radionuclidi ad elevata purezza mediante la tecnica ISOL (Isotope-Separation On-Line).
Per quanto concerne il gruppo di Fisica dell’Istituto Nazionale di Fisica Nucleare e del Dipartimento
di Fisica e Astronomia di Padova, l’obiettivo `e quello di studiare la produzione di 111Ag ed altri radioisotopi innovativi attraverso l’irraggiamento in reattore di un campione di Palladio naturale e di un
campione di Palladio arricchito, per quanto concerne la prima fase del progetto, ed al ciclotrone SPES
dei Laboratori Nazionali di Legnaro per le prossime fasi. La misura della produzione dei radioisotopi
di interesse `e realizzata principalmente tramite analisi di spettroscopia gamma.
L’analisi successivamente presentata si concentra sullo studio degli spettri di emissione di un campione
di Palladio arricchito irraggiato a febbraio 2021 mediante il reattore nucleare TRIGA MARK II presso
il L.E.N.A. di Pavia, previe opportune analisi inerenti calibrazione, risoluzione ed efficienza dei detector
utilizzati, ossia HPGe e LaBr3, effettuate all’INFN di Legnaro.
Dai suddetti spettri sono stati identificati ed analizzati i principali radionuclidi prodotti (109P d,
111mP d,
111Ag) e per ognuno di essi si è trovata sia una stima per il tempo di dimezzamento che per l’attivit
Supernova neutrino detection in JUNO, a large liquid scintillator neutrino detector
Get PDFThe Jiangmen Underground Neutrino Observatory (JUNO) is a multi-purpose neutrino experiment under construction in South China. The 20 kton of highly transparent Liquid Scintillator (LS) are contained in an acrylic sphere surrounded by 17612 20” PhotoMultiplier Tubes (PMTs) and 25600 3” PMTs. JUNO aims at providing an energy resolution better than 3% at 1 MeV and thus offers exciting opportunities for addressing various important topics in neutrino and astroparticle physics. For instance, neutrinos play a crucial role during all stages of stellar collapse and explosion. The signature of a supernova explosion is a sudden increase of the neutrino interaction rate in the detector of several orders of magnitude (from below 1 kHz up to 1 MHz) for a short time O(1 s). Therefore the readout electronics has to withstand very high rates for a limited amount of time without data losses. The JUNO Padova research group is responsible for the design and development of the large PMTs readout electronics. The PMTs output signal is processed and stored temporarily in a local memory
before being sent to the data acquisition, once validated by the trigger electronics. Besides the local memory situated in the readout-board FPGA, a 2 GBytes DDR3 SDRAM memory is available and it is used to provide a larger memory buffer in the exceptional case of a sudden increase of the input rate. A small experiment with 48 small size PMTs reading out the light coming from a 20 liter LS
detector has been assembled at the Legnaro National Laboratories in Legnaro, Italy. Another setup has been built at the Institute of High Energy Physics in Beijing, China.
The first part of the thesis concerns the performance assessment of the electronics, carried out by simulating the production of high-rate scintillation photons in the LS and testing the highest rates sustainable by the system. By retrieving the amount of expected events and the number of correctly read events, it is possible to compute the efficiency of the setup at a fixed rate. This made it possible
to understand the rate range in which the system can work and when the DDR3 is necessary. Finally, rate measurements employing exclusively the DDR3 memory were collected thanks to a third setup at the Department of Physics and Astronomy in Padua, Italy. The purpose of this test is to understand whether the memory is capable of storing all the useful high-rate events by overrunning the usual data transfer bandwidth between the read-out electronics and the DAQ
Sismicità e deformazione crostale nell'area di Vittorio Veneto - Asolo (Treviso, Italia)
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Voter model on k-partite graphs. Asymptotic behavior conditional on non-absorption
Get PDFThanks to its incredible ability to model real-life problems, the research field of interacting particle systems has become one of the main application of stochastic processes. We treated the case of the voter model, where the set of particles represents a group of people each of whom holds one of two different opinions (0 and 1) on a political issue. The state space of the process is defined by [image: \{0,1\}^V], where [image: V] represents the vertex set of a complete [image: k]-partite graph with parameters [image: n,m_1,\dots,m_{k-1}]. Since the graph is finite, consensus, i.e. states where opinions are all equal, occurs almost surely.
The aim of the thesis is to investigate the asymptotic behavior of the
quasi-stationary distributions, for the process conditioned to never reach consensus, as [image: n] tends to infinity. In particular, we want to find out if the lack of consensus is due to a minority number of dissenters, or if the opinions are relatively balanced
Machine Learning approaches in Neuroscience:behavioral and sleep classification
No full textThe understanding of sleep is of paramount importance from a scientific and clinical point
of view. Brain disorders, such as Autism and Alzheimer, show disrupted sleep patterns that
contribute to the progression of the disease. To obtain efficacious drugs, an important step
is to study and test them in rodents, with the hope to extrapolate the findings to humans.
In such preclinical studies, it is fundamental to correctly identify and classify sleep phases in
order to compare them to the ones found in humans. However, very few works have been
carried out in this regard. This Master thesis work is aimed at critically studying this aspect
through an approach based on Machine Learning techniques applied to EEG and accelerometer
signals. This work will lay the foundation to investigate the differences between wildtype
and transgenic mice with the purpose of characterizing the sleep impairment biomarkers of
the disease and its trajectory throughout the rodent's life
Studio della variegazione superficiale e dell'evoluzione superficiale della cometa 67P/C-G osservata da Rosetta/OSIRIS
Get PDFRivelazione nell’infrarosso di archi gravitazionali in galassie selezionate nel submillimetrico.
Get PDFIsomer decay spectroscopy ofneutron-rich nuclei around A ∼210
Get PDFABSTRACT: This thesis presents the results of an experiment performed at the GSI Laboratory, Darmstadt, Germany. The experiment aimed at studying the nuclear structure of neutron-rich nuclei around the 208Pb double-shell closure nucleus. Isotopes were produced via projectile fragmentation, separated and selected through the FRS spectrometer and studied via the RISING setup in its "stopped beam" configuration. The experimental technique employed is the isomer-decay γ-ray spectroscopy. Ten different isotopes, ranging from Au to Po, have been studied: their partial level schemes have been reconstructed from γ- γ coincidences, while the lifetime of their isomeric states has been extracted from the time distribution of the de-excitation γ rays. A new transition of 533 keV in 212Po has been found, which has no counterpart in literature, and it is assigned to the long-sought 21- → 18+ E3. A strength between an upper value of 18 ± 4 W.u. and a lower bound of 12 ± 4 W.u. is deduced for this transition. The assignment is deduced from its isomeric ratio and systematics in the region. Results are compared to shell-model calculations
IMPLEMENTAZIONE DI ALGORITMI DI PREVISIONE PER SERIE STORICHE, UN PROGETTO STAGE CON ZUCCHETTI S.p.A.
Get PDFTale lavoro di Tesi è stato elborato in seguito all'esperienza di stage lavorativo svolto con l'azienda Zucchetti S.p.A. e si pone come scopo quello di analizzare nel dettaglio il progetto realizzato. L'obiettivo princiapale del lavoro di stage consisteva nell'implementazione di algoritmi basati su tecniche e modelli predittivi da applicare nell'ambito dell'analisi delle serie storich