Signal Formation in the new Time Projection Chambers of the T2K Upgraded Experiment

The goal of the T2K experiment is to obtain new insights on the phenomena of neutrino oscillations. In order to improve the near detector of the experiment an upgrade is planned, with the addition, among other detectors, of two HA-TPCs (High Angle Time Projection Chambers). The use of MICROMEGAS with an additional resistive layer (ERAM) adds an effect of charge spread, enabling higher resolution for a fixed number of electronic channels and improved spark protection. The scope of this thesis is to gain a better understanding of the physics of charge spread and a detailed signal formation description. A finite element simulation is developed, allowing to validate analytical models of this phenomena. Moreover, the previously unaccounted for effect of the ion drift in the amplification gap is studied. A method exploiting a complete model of signal formation, together with the response of the electronic front-end, is proposed for the characterization of the acquired pad signals, serving as a starting point for future calibrations and analyses. Additionally, the installation and setup of the HA-TPC prototype for a test beam at the DESY laboratory in Hamburg is reported, together with the application of the aforementioned analysis method to the early data collected. L'obiettivo dell'esperimento T2K è l'avanzamento della comprensione del fenomeno delle oscillazioni dei neutrini. Per migliorare le caratteristiche del rivelatore vicino ne è stato pianificato un aggiornamento che prevede l'installazione, oltre ad altri rivelatori, di due camere a proiezione temporale ad alto angolo (HA-TPC). L'uso di MICROMEGAS con l'aggiunta di uno strato resistivo introduce un effetto di diffusione della carica che permette di ottenere una maggiore risoluzione, a parità di numero di canali di elettronica, migliorandone inoltre la protezione dalle scariche. La finalità di questa tesi è ottenere una più completa comprensione della fisica della diffusione della carica e descrivere dettagliatamente la formazione del segnale. Una simulazione agli elementi finiti è stata sviluppata, permettendo la validazione dei modelli analitici di questo fenomeno. In seguito è stato studiato l'effetto del moto di deriva degli ioni nello strato di amplificazione, finora mai considerato. È poi stato proposto un metodo che sfrutta un modello completo di formazione del segnale e della risposta dell'elettronica di front-end, utilizzabile per la caratterizzazione del segnale acquisito da ogni pad e che potrà servire come punto di partenza per future calibrazioni e analisi. In aggiunta si descrive la preparazione e l'installazione del prototipo della HA-TPC per un test beam ai laboratori di DESY, ad Amburgo. La procedura di analisi descritta precedentemente è stata poi applicata ai dati appena ottenut

A low-latency feedback system for the control of horizontal betatron oscillations

Reinforcement learning (RL) algorithms are investigated at KIT as an option to control the beam dynamics at storage rings. These methods require specialized hardware to satisfy throughput and latency constraints dictated by the timescale of the relevant phenomena. The KINGFISHER platform, based on the novel Xilinx Versal Adaptive Compute and Acceleration Platform, is an ideal candidate to deploy RL-on-a-chip thanks to its ability to execute computationally intensive and low latency feedback loops in the order of tens of microseconds. In this publication, we will present the integration of the KINGFISHER system at the Karlsruhe Research Accelerator (KARA), as a proof-of-principle turn-by-turn control feedback loop, to control induced transversal oscillations of an electron beam

Production of He-4 and (4) in Pb-Pb collisions at root(NN)-N-S=2.76 TeV at the LHC

Results on the production of He-4 and (4) nuclei in Pb-Pb collisions at root(NN)-N-S = 2.76 TeV in the rapidity range vertical bar y vertical bar <1, using the ALICE detector, are presented in this paper. The rapidity densities corresponding to 0-10% central events are found to be dN/dy4(He) = (0.8 +/- 0.4 (stat) +/- 0.3 (syst)) x 10(-6) and dN/dy4 = (1.1 +/- 0.4 (stat) +/- 0.2 (syst)) x 10(-6), respectively. This is in agreement with the statistical thermal model expectation assuming the same chemical freeze-out temperature (T-chem = 156 MeV) as for light hadrons. The measured ratio of (4)/He-4 is 1.4 +/- 0.8 (stat) +/- 0.5 (syst). (C) 2018 Published by Elsevier B.V.Peer reviewe

Studio sperimentale di una reazione nucleare con Active Target TPC

L'utilizzo di un bersaglio che funge anche da rivelatore (active target) fornisce vantaggi in termini di luminosità e risoluzione energetica per lo studio di reazioni nucleari a bassa energia. Questo approccio risulta fondamentale per sfruttare fasci di bassa intensità (10^2 - 10^3 particelle per secondo) come quelli esotici che saranno prodotti a SPES presso i Laboratori Nazionali di Legnaro. Questo lavoro di tesi riguarda la caratterizzazione di un rivelatore a bersaglio attivo (Dimostratore di ACTAR) utilizzando i dati raccolti durante la campagna sperimentale svoltasi presso i Laboratori Nazionali del Sud (INFN) tra Dicembre 2018 e Febbraio 2019. Verranno descritti la preparazione dei dati, il processamento dei segnali e gli algoritmi di analisi delle reazioni indotte da un fascio di 11B a 32 MeV su isobutano, utilizzando la trasformata di Hough per la ricostruzione degli eventi fisici. / The combined use of a target acting, at the same time, as a detector (active target) allows improvements of both luminosity and energy resolution for studying low energy nuclear reactions. This approach turns out to be fundamental for taking advantage of low intensity beams (10^2 - 10^3 particles per second) like the ones that will be produced by SPES at Laboratori Nazionali di Legnaro. This thesis concerns the characterization of an active target (ACTAR demonstrator) using the data collected during the experimental campaign at Laboratori Nazionali del Sud between December 2018 and February 2019. A description of the data preparation, signal processing and analysis algorithms will be provided. In particular, the reactions induced by an 11B beam at 32 MeV on isobutane will be analyzed, using Hough transform for the reconstruction of the physical events

Use of Poly Lactic-co-glycolic Acid Nano and Micro Particles in the Delivery of Drugs Modulating Different Phases of Inflammation

Chronic inflammation contributes to the pathogenesis of many diseases, including apparently unrelated conditions such as metabolic disorders, cardiovascular diseases, neurodegenerative diseases, osteoporosis, and tumors, but the use of conventional anti-inflammatory drugs to treat these diseases is generally not very effective given their adverse effects. In addition, some alternative anti-inflammatory medications, such as many natural compounds, have scarce solubility and stability, which are associated with low bioavailability. Therefore, encapsulation within nanoparticles (NPs) may represent an effective strategy to enhance the pharmacological properties of these bioactive molecules, and poly lactic-co-glycolic acid (PLGA) NPs have been widely used because of their high biocompatibility and biodegradability and possibility to finely tune erosion time, hydrophilic/hydrophobic nature, and mechanical properties by acting on the polymer’s composition and preparation technique. Many studies have been focused on the use of PLGA-NPs to deliver immunosuppressive treatments for autoimmune and allergic diseases or to elicit protective immune responses, such as in vaccination and cancer immunotherapy. By contrast, this review is focused on the use of PLGA NPs in preclinical in vivo models of other diseases in which a key role is played by chronic inflammation or unbalance between the protective and reparative phases of inflammation, with a particular focus on intestinal bowel disease; cardiovascular, neurodegenerative, osteoarticular, and ocular diseases; and wound healing

Where Brain, Body and World Collide

The production cross section of electrons from semileptonic decays of beauty hadrons was measured at mid-rapidity (|y| &lt; 0.8) in the transverse momentum range 1 &lt; pt &lt; 8 Gev/c with the ALICE experiment at the CERN LHC in pp collisions at a center of mass energy sqrt{s} = 7 TeV using an integrated luminosity of 2.2 nb^{-1}. Electrons from beauty hadron decays were selected based on the displacement of the decay vertex from the collision vertex. A perturbative QCD calculation agrees with the measurement within uncertainties. The data were extrapolated to the full phase space to determine the total cross section for the production of beauty quark-antiquark pairs