1,445 research outputs found
Quench Level of the HL-LHC IR Quadrupoles
No full textThe scope of the Large Hadron Collider Hi-Lumi Project at CERN includes the installation of several superconducting magnets wound with Rutherford cables. The quench level of these magnets (i.e. the maximum energy that a cable can tolerate without quenching) is a key value required to set magnet protection from beam losses, and is expected to be significantly different from the computed and measured levels of the LHC NbTi magnets. In this work, we applied a one-dimensional numerical model of multi-strand Rutherford cables to simulate the electro-thermal instabilities caused by the heat released by the particle beam losses. Two models have been applied, one based on the analysis of the single strand, and the other accounting for all the strands in the multi-strand cable. The results of these two models are compared to analyze the effects of heat and current redistribution during quench. A comparison between the quench energy values obtained for the conductor in the working conditions of the LHC Hi-Lumi inner triplet low-β quadrupole (MQXF) and those of the NbTi Rutherford cable of the LHC main quadrupole magnet (MQ) is presented
David Audretsch: A Source of Inspiration, a Co-author, and a Friend
No full textIn this chapter, Enrico Santarelli discusses the profound impact that David had on his career. Beginning with a conference in Budapest, Santarelli and David bocame close friends and colleagues. They went on to collaborate on many papers and projects, several of which Santarelli highlights below
Dialogo con Enrico Palandri
No full textA conversation with Enrico Palandri aimed at contextualizing his work as an author
Analysis of a Novel Toroidal Configuration for Hadron Therapy Gantries
No full textHadron therapy refers to a medical treatment that uses hadron beams (i.e. protons and ions) to deliver localized energy that suppresses cancerous cells, sparing the neighbouring healthy tissues from unwanted radiation. The major technical components of a hadron therapy centre are the particle accelerator (cyclotron, synchrotron, or linac) and the beam delivery system that controls, shapes and orients the particles towards the area to be treated. The beam delivery can consist of fixed transfer lines, or it can include a gantry, a transfer line that rotates around the patient and allows radiation from multiple directions. The present work investigates a new toroidal gantry for hadron therapy, named GaToroid. This novel gantry configuration allows the dose delivery from a discrete number of angles avoiding magnets as well as patient rotation. Compared to traditional gantries that require rotating magnets, this improvement is made possible by a toroidal magnet operating in steady-state. This design constitutes the ideal conditions for the use of superconductors to generate a significantly higher magnetic field compared to normal-conducting solutions, as well as to reduce the weight and footprint of the magnets. The study of a GaToroid system requires the integration of several aspects of physics and engineering. In this framework, the focus of this research is on the design of the superconducting coils integrated with beam optics and particle tracking analyses. The first part of the thesis illustrates the optimization of the toroidal magnet. Coupling two-dimensional particle tracking and magnetic field calculations, an algorithm was developed to identify optimal gantry configurations that maximize the energy acceptance of the system. Two solutions composed of 16 coils, differing in high and low values of engineering current density, were investigated. In line with current clinical requirements, the beams converged at the isocenter within 1 mm over the whole treatment energy spectrum for both configurations.
The second part of the thesis describes the algorithm implemented for the two- and three-dimensional particle tracking. Building upon the results of the magnetic optimization, a linear beam optics formalism was developed to determine the focusing properties of GaToroid. The third part of the thesis focuses on the engineering design of the low current density solution. Using two thermo-electric models, lumped and one-dimensional, the Nb-Ti and ReBCO cable geometries were validated, together with the quench protection system. Furthermore, analytical and numerical studies on mechanics made it possible to estimate the overall footprint and weight of the system. Results show that, compared with the state-of-the-art gantries, the proposed GaToroid solution has the potential to be more compact and lighter by at least a factor two. Finally, the last part of the thesis describes the design of a scaled-down demonstrator wound with ReBCO tapes. Studies on quench protection, mechanics and experimental implementation aimed at testing the use of ReBCO technology for GaToroid coils are discussed. In conclusion, this work presents the first overall description of a GaToroid system, ranging from the analytical definition, magnetic optimization, particle tracking and magnet engineering. The investigation of this new toroidal paradigm for gantries represents a quantum step toward more compact and less expensive solutions for hadron therapy centres.SCI-IC-B
Coupling of Cyclotrons to Linacs for Medical Applications
No full textCyclotron and Linac technologies cover the vast majority of accelerator solutions applied to medicine. Cyclotrons with beams of H+/H-around 20 MeV are found for radioisotope production and cyclotrons with beams up to 250 MeV are widely used for protontherapy. Linacs are present in every medium-sized hospital with electron beams up to 20 MeV for radiotherapy and radioimaging. They have also recently become available as commercial products for protontherapy. The coupling of these two strong technologies enables to expand the capabilities of cyclotrons by using linacs as boosters. This opens the way to innovative accelerator systems allowing both radioisotope production and ion beam therapy (cyclinacs), new treatment techniques (high energy protontherapy) and new imaging techniques (proton radiography). This paper provides an overview of the technical challenges linked to coupling cyclotrons to linacs and the various solutions at hand
Enrico Cattaneo : Fotografare un'idea
No full textOltre ad aver raccontato l’arte e gli artisti del secondo Novecento attraverso la documentazione di cinquant’anni di mostre, studi e grandi manifestazioni pubbliche in Italia, Enrico Cattaneo (Milano, 1933-2019) ha sviluppato una personalissima ricerca visuale sui modi, i soggetti e i materiali della fotografia.
Questi due aspetti della sua attività, inseparabili fra loro come le due facce di una medaglia, si ricompongono nella fisionomia unitaria di un autore capace di mettere in questione i presupposti tecnici e concettuali del linguaggio fotografico.
Come lui stesso ha scritto: “L’opera d’arte contemporanea è spesso una cosa più un’idea... Difficile fotografare un’idea”.In addition to having chronicled art and artists of the second half of the 20th century by documenting fifty years of exhibitions, art research, and major public events in Italy, Enrico Cattaneo (Milan, 1933–2019) developed a highly personal visual investigation on the modes, languages, and materials of photography.
These two facets of his activity, indissolubly linked like the two sides of a coin, are recomposed in the overall profile of an author capable of questioning the technical and conceptual foundations of photography.
As he himself has written: ‘The contemporary work of art is often made up of a tangible thing and an idea ... It is difficult to capture an idea on film.
Paolo Enrico Arias in Abruzzo
No full textThe author emphasizes P.E.Arias' contribution to archaeological researches in the Abruzzi, thanks to the Pisan Archaeological Mission at Collelongo (AQ)
Sade : opus contra theatrum
No full textDepuis 1999, date à laquelle il annonce son intention d’entamer un cycle de création ayant pour base les oeuvres du marquis de Sade, Enrico Frattaroli a créé 5 spectacles formant un ensemble intitulé Sade convivium. Dans le document qu’il a préparé pour L’Annuaire théâtral, il explique la démarche artistique singulière par laquelle il utilise la matière sadienne tout en évitant de mettre en scène à la fois son théâtre et son oeuvre romanesque.Since 1999, the date he announced his intention to write a cycle of plays based on the works of the Marquis de Sade, Enrico Frattaroli has created five works in this ensemble that bears the title The Sade convivium. In the document he has prepared for L’Annuaire théâtral, he explains his unique approach whereby he uses the works of Sade as a creative material rather than attempting to produce the plays or the novels of the French author
Una mirada desde la memoria a dos experiencias de teatros políticos locales. : En torno de los escritos dramáticos libertarios de Enrico Giulio
No full textAfter considering the political background of Argentina during the three first decades of the xxth century, the author analyzes a very interesting example of anarchist theatre: Falsas promesas, one of the dramatic texts of Enrico Giulio, ceramist worker and libertarian poet.Después de considerar el trasfondo político argentino de las tres primeras décadas del siglo XX, el autor analiza una interesante ejemplo del teatro anarquista: Falsas promesas, uno de los textos dramáticos de Enrico Giulio, obrero ceramista y poeta libertario
GaToroid group photo
No full textDemonstrator Nb-Ti coil for the GaToroid project, scaled 1:3 from the proton gantry design. Next to the coil (right) is visible a scaled model of the whole toroidal gantry magnet, with couch. Present in the picture is part of the team of technicians, engineers and physicists that have designed, built and tested the demonstrator. Project co-funded by the CERN Budget for Knowledge Transfer to Medical Applications. Enrico Felcini (right of the coil) and Ariel Haziot (left of the coil), have completed their PhD study (Felcini) and fellowship (Haziot) within the scope of the GaToroid project. Luca Bottura has initiated the conceptual study that has led to the demonstrator construction and test
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