Strangeness production in p-Pb and Pb-Pb collisions with ALICE at LHC

The main goal of the ALICE experiment is to study the properties of the hot and dense medium created in ultra-relativistic heavy-ion collisions. The measurement of the (multi-)strange particles is an important tool to understand particle production mechanisms and the dynamics of the quark-gluon plasma (QGP). We report on the production of K$^{0}_{S}$, $\Lambda$($\overline{\Lambda}$), $\Xi^{-}$($\overline{\Xi}^{+}$) and $\Omega^{-}$($\overline{\Omega}^{+}$) in proton-lead (p-Pb) collisions at $\sqrt{s_{\rm NN}}$ = 5.02 TeV and lead-lead (Pb-Pb) collisions at $\sqrt{s_{\rm NN}}$ = 2.76 TeV measured by ALICE at the LHC. The comparison of the hyperon-to-pion ratios in the two colliding systems may provide insight into strangeness production mechanisms, while the comparison of the nuclear modification factors helps to determine the contribution of initial state effects and the suppression from strange quark energy loss in nuclear matter.Comment: 4 pages, 3 figures, Proceedings of SQM'16 conference, 27 June - 1 July 201

Multi-strange baryon production in Pb-Pb and pp collisions at sNN\sqrt{s_{NN}} = 2.76 TeV with the ALICE experiment at the LHC

The production of $\Xi^{-}$ and $\Omega^{-}$ baryons and their anti-particles in Pb-Pb and pp collisions at $\sqrt{s_{NN}}$ = 2.76 TeV has been measured by the ALICE collaboration. The transverse momentum spectra at mid-rapidity (|y| < 0.5) in pp and Pb-Pb collisions for five centrality intervals have been compared with model predictions. Hyperon yields and spectra in Pb-Pb collisions, normalized to the corresponding measurements in pp at the same centre-of-mass energy, allow the study of the strangeness enhancement and the nuclear modification factor as a function of the transverse momentum ($p_{T}$) and collision centrality.Comment: 4 pages, 3 figures. Proceedings of the Strangeness in Quark Matter Conference (SQM 2013), 22nd - 27th July 2013, published by the Open Access Journal of Physics: Conference Series (JPCS), in the IOP conference serie

Multi-strange baryon production in pp, p-Pb and Pb-Pb collisions at LHC measured with ALICE

Transverse momentum spectra and yields of charged $\Xi$ and $\Omega$ at mid-rapidity in pp, p-Pb and Pb-Pb collisions at the LHC have been measured by the ALICE Collaboration. These baryons are identified by reconstruction of their weak decay topology, in modes with only charged decay products, using the excellent tracking and particle identification capabilities of the detector. The recent measurements of the multi-strange baryon production relative to non-strange particles in p-Pb collisions are presented: this would help to understand the change in relative strangeness production from pp collisions to Pb-Pb collisions. Results on the nuclear modification factors for the charged $\Xi$ and $\Omega$ particles, compared with those for other light particles, are also reported.Comment: 4 pages, 3 figures, Proceedings of the Hot Quarks 2014 conference, 21-28 September 2014, Las Negras - Cabo de Gata Natural Park (Spain

ALICE ITS upgrade for LHC Run 3: commissioning in the laboratory

ALICE is the CERN LHC experiment optimised for the study of the strongly interacting matter produced in heavy-ion collisions and devoted to the characterisation of the quark-gluon plasma. To achieve the physics program for LHC Run 3, a major upgrade of the experimental apparatus is ongoing. A key element of the upgrade is the substitution of the Inner Tracking System (ITS) with a completely new silicon-based detector whose features will allow the reconstruction of rare physics channels, not accessible with the previous layout. The enabling technology for such a performance boost is the adoption of custom-designed CMOS MAPS as detecting elements. The installation of the detector in the ALICE cavern is completed and few months of commissioning will allow the final integration into the central systems. In this talk, an overview of the adopted technologies as well as the status of the detector commissioning will be given.Comment: Proceedings of International Conference on Technology and Instrumentation in Particle Physics (TIPP2021), May 24-28, 2021, Online format, 4 page

Multi-strange baryon production in pp, p-Pb and Pb-Pb collisions measured with ALICE

The production of {\Xi}$^{-}$ and {\Omega}$^{-}$ baryons and their anti-particles in pp, p-Pb and Pb-Pb collisions has been measured by the ALICE Collaboration. These hyperons are reconstructed via the detection of their charged weak-decay products, which are identified through their measured ionisation losses and momenta in the ALICE Time Projection Chamber. Comparing the production yields in Pb-Pb and pp collisions, a strangeness enhancement has been measured and found to increase with the centrality of the collision and with the strangeness content of the baryon; moreover, in the comparison with similar measurements at lower energies, it decreases as the centre-of-mass energy increases, following the trend already observed moving from SPS to RHIC. Recent measurement of cascade and {\Omega} in p-Pb interactions are compared with results in Pb-Pb and pp collisions and with predictions from thermal models, based on a grand canonical approach. The nuclear modification factors for the charged {\Xi} and {\Omega}, compared to the ones for the lighter particles, are also presented.Comment: 5 pages, 3 figures, Proceedings of the QCD@Work 2014 conference, 16-19 June 2014, Giovinazzo (Italy

ALICE ITS 3: the first truly cylindrical inner tracker

The high integration density of MAPS, with silicon sensor and readout electronics implemented in the same device, allows very thin structures with a greatly reduced material budget. Thicknesses of $\mathcal{O}$(50~$\mu$m), values at which silicon chips become flexible, are readily used in many applications. In addition, MAPS can be produced in sensors of wafer size by a process known as stitching. This in turn allows to build detector elements that are large enough to cover full tracker half-layers with single bent sensors. The ALICE ITS~3 project is planning to build a new vertex tracker based on truly cylindrical wafer-scale sensors, with <0.05\% X/X$_{0}$ per layer and located as close as 18 mm to the interaction point. R\&D on all project aspects (including mechanics for bent wafer-scale devices, test beams of bent MAPS, design of stitched sensors) is rapidly progressing with the aim for installation during LHC long shutdown 3 (2025--2027). This contribution summarises the project motivation, its R\&D schedule, and will show selected highlights of recently accomplished project milestones, including full-scale engineering prototypes with dummy chips and small-scale, fully functional assemblies of functional, bent MAPS.Comment: 4 pages, 3 figures, proceedings at the 12th International Conference on Position Sensitive Detectors - PSD12 12-17 September, 2021, Birmingham, U.

ALICE Inner Tracking System Upgrade: construction and commissioning

ALICE (A Large Ion Collider Experiment) is the CERN LHC experiment optimized for the study of the strongly interacting matter produced in heavy-ion collisions and devoted to the characterization of the Quark-Gluon Plasma. To achieve the physics program for LHC Run 3 and 4, ALICE is undergoing a major upgrade of the experimental apparatus during the ongoing second long LHC shutdown. A key element of the ALICE upgrade is the substitution of the Inner Tracking System (ITS) with a completely new silicon-based detector whose features will allow the reconstruction of rare physics channels which could not be accessed before with the ITS layout used during LHC Run 1 and 2. The enabling technology for such performance boost is the adoption of custom-designed MAPS (Monolithic Active Pixel Sensors) as detecting element. In this proceedings, the status of the construction and commissioning of the ITS upgrade will be detailed. The completion of the modules construction will be achieved soon and, in the meantime, the commissioning in laboratory is proceeding using the components already integrated in the detector.Comment: 4 pages, 2 figures, proceedings to Strangeness in Quark-Matter 2019 conferenc

Sviluppo di metodi per l'analisi in real-time di immagini endoscopiche

L’obiettivo del presente lavoro è di sviluppare un sistema per l’elaborazione di immagini endoscopiche in tempo reale, cioè in contemporanea all’esecuzione della procedura diagnostica. La tesi è stata svolta in collaborazione con l’azienda Era Endoscopy S.r.l., con sede a Peccioli (Pisa), specializzata nella ricerca, lo sviluppo e la commercializzazione di dispositivi medicali dalle eccellenti performance in termini di sicurezza e assenza di dolore. Il cancro del colon-retto è la più frequente neoplasia (tumore maligno) dell'apparato gastrointestinale e in assoluto una delle principali cause di morte per cancro. La necessità di una precocità sempre crescente nel rilevamento di neoplasie, unita al desiderio di un migliore riconoscimento di tali lesioni maligne, talvolta difficili da distinguere da analoghe manifestazioni cliniche come infiammazioni o traumi, ha accelerato lo sviluppo di nuove tecnologie nell’ambito dell’endoscopia digestiva. Ciò ha portato alla nascita della cosiddetta “endoscopia potenziata” o image-enhanced endoscopy (IEE). In questo contesto di progresso tecnologico si inserisce il presente lavoro, che ha come oggetto il sistema Endotics, un rivoluzionario dispositivo endoscopico completamente monouso e dall’esclusivo meccanismo di avanzamento robotico. In particolare, l’attività di sviluppo si concentra sulla componente software, cioè sull’elaborazione digitale di immagini allo scopo di creare un sistema di visione migliorata che possa aiutare il medico nella caratterizzazione delle lesioni del colon e quindi in una diagnosi differenziale e precoce