Magnetic channels are used in almost all cyclotrons to focus radially the beam along the extraction path through the coils and yoke region, where the rapid fall off of the magnetic field produces a ...strong vertical focusing and radial defocusing of the beam. These magnetic channels consist generally of three iron bars. The current sheet approximation has been generally used to evaluate quickly the performance of magnetic channels. For the new magnetic channels to be used in the upgrade of the LNS-INFN k800 Superconducting Cyclotron, a new method was developed to investigate complex configurations and to achieve higher magnetic gradients in a larger area. The optimization procedure is based on a genetic algorithm implemented on MATLAB code and using the COMSOL code to perform the 2D magnetic field simulations. Moreover, the use of permendur vanadium in alternative to iron allows to reduce the volume of the bars and mainly the magnetic force. The results of our simulations are here presented.
The Superconducting Cyclotron (CS) at INFN-LNS in Catania is currently under an upgrade process. The plan is to deliver beams of ions with mass number A ⩽ 40 with power up to 10 kW by means of beam ...intensity increase. This ambitious goal can be achieved by increasing the efficiency of the injection and extraction processes. An extraction efficiency close to 100% is expected by extracting the specific ion beams from the CS by stripping and no longer by electrostatic deflectors. The beams are injected axially and bent onto the median plane with a spiral inflector. Currently, the injection efficiency is around 15% including the effect of a drift buncher placed in the axial injection line. In order to increase the injection efficiency, the study of an upgraded CS central region is ongoing at INFN-LNS. In this paper, the results of simulations of beam tracking through the cyclotron axial bore, the spiral inflector, the central region and further up to the extraction system are presented.
At the Istituto Nazionale di Fisica Nucleare-Laboratori Nazionali del Sud (INFN-LNS) in Catania, Italy, the first Italian protontherapy facility, named Centro di AdroTerapia e Applicazioni Nucleari ...Avanzate (CATANA) has been built in collaboration with the University of Catania. It is based on the use of the 62-MeV proton beam delivered by the K=800 Superconducting Cyclotron installed and working at INFN-LNS since 1995. The facility is mainly devoted to the treatment of ocular diseases like uveal melanoma. A beam treatment line in air has been assembled together with a dedicated positioning patient system. The facility has been in operation since the beginning of 2002 and 66 patients have been successfully treated up to now. The main features of CATANA together with the clinical and dosimetric features will be extensively described; particularly, the proton beam line, that has been entirely built at LNS, with all its elements, the experimental transversal and depth dose distributions of the 62-MeV proton beam obtained for a final collimator of 25-mm diameter and the experimental depth dose distributions of a modulated proton beam obtained for the same final collimator. Finally, the clinical results over 1 yr of treatments, describing the features of the treated diseases will be reported.
The LNS Superconducting Cyclotron (CS) has been working for 20 years making a wide range of ions and energies available. Many experiments are performed each year. In the near future a major upgrade ...is planned. This will allow to overcome the major limitation of the CS, which is the beam power delivered to the users, that at present does not exceed 100 W. In the new version of the CS, the extracted beam power will be increased up to a factor 100. This improvement will be reached extracting by stripping a specific set of light ions and energies extracted by stripping. Nevertheless, the extraction through the two electrostatic deflectors, providing a beam power limited to 100 W, will be also maintained to fulfil the users requests. The new design could strongly affect the beam dynamics. The iron yoke penetrations do not respect the three folds symmetry of our cyclotron and have a complex shape, due to the double extraction methods and all services entrances. This inhomogeneity produces unwanted field harmonics, which have to be reduced as much as possible to avoid beam precession or second order effects. Here the study accomplished to minimize the perturbation of the non- three fold field symmetry using the current sheet approximation (CSA) is presented, along with the state-of-art configuration of the updated cyclotron.
Neutrinoless double beta decay (0vββ) is considered the best potential resource to access the absolute neutrino mass scale. Moreover, if observed, it will signal that neutrinos are their own ...anti-particles (Majorana particles). Presently, this physics case is one of the most important research "beyond Standard Model" and might guide the way towards a Grand Unified Theory of fundamental interactions. Since the 0vββ decay process involves nuclei, its analysis necessarily implies nuclear structure issues. In the NURE project, supported by a Starting Grant of the European Research Council (ERC), nuclear reactions of double charge-exchange (DCE) are used as a tool to extract information on the 0vββ Nuclear Matrix Elements. In DCE reactions and ββ decay indeed the initial and final nuclear states are the same and the transition operators have similar structure. Thus the measurement of the DCE absolute cross-sections can give crucial information on ββ matrix elements. In a wider view, the NUMEN international collaboration plans a major upgrade of the INFN-LNS facilities in the next years in order to increase the experimental production of nuclei of at least two orders of magnitude, thus making feasible a systematic study of all the cases of interest as candidates for 0vββ.
The NUMEN Project, proposed at INFN Laboratori Nazionali del Sud (LNS) in Catania, has the aim to access the nuclear matrix elements, entering the expression of the life time of double beta decay, by ...relevant cross sections of double charge exchange reactions. The basic point, on which it is based this innovative technique, is the coincidence of the initial and final state wave-functions in the two classes of processes and the similarity of the transition operators. A key aspect of the Project is the use of MAGNEX large acceptance magnetic spectrometer, for the detection of the ejectiles, and of the INFN LNS K800 Superconducting Cyclotron (CS), for the acceleration of the required high resolution and low emittance heavy-ion beams.
An innovative technique to access the nuclear matrix elements entering the expression of the life time of the double beta decay by relevant cross section measurements of double charge exchange ...reactions is proposed. A key aspect of the project is the use of the MAGNEX large acceptance magnetic spectrometer, for the detection of the ejectiles, and of the LNS K800 Superconducting Cyclotron (CS), for the acceleration of the required high resolution and low emittance heavy-ion beams, already in operation at INFN Laboratory Nazionali del Sud in Catania (Italy). However, a major upgrade is foreseen for the INFN-LNS research infrastructure to cope with beam currents as high as several ppA required by the project.
An innovative technique to access the nuclear matrix elements entering the expression of the life time of the double beta decay by relevant cross sections measurements of double charge exchange ...reactions is proposed. A key aspect of the project is the use of the MAGNEX large acceptance magnetic spectrometer, for the detection of the ejectiles, and of the LNS K800 Superconducting Cyclotron (CS), for the acceleration of the required high resolution and low emittance heavyion beams, already in operation at INFN Laboratory Nazionali del Sud in Catania (Italy).
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The article describes the main achievements of the NUMEN project together with an updated and detailed overview of the related R&D activities and theoretical developments. NUMEN proposes an ...innovative technique to access the nuclear matrix elements entering the expression of the lifetime of the double beta decay by cross section measurements of heavy-ion induced Double Charge Exchange (DCE) reactions. Despite the fact that the two processes, namely neutrinoless double beta decay and DCE reactions, are triggered by the weak and strong interaction respectively, important analogies are suggested. The basic point is the coincidence of the initial and final state many-body wave functions in the two types of processes and the formal similarity of the transition operators. First experimental results obtained at the INFN-LNS laboratory for the
40
Ca(
18
O,
18
Ne)
40
Ar reaction at 270MeV give an encouraging indication on the capability of the proposed technique to access relevant quantitative information. The main experimental tools for this project are the K800 Superconducting Cyclotron and MAGNEX spectrometer. The former is used for the acceleration of the required high resolution and low emittance heavy-ion beams and the latter is the large acceptance magnetic spectrometer for the detection of the ejectiles. The use of the high-order trajectory reconstruction technique, implemented in MAGNEX, allows to reach the experimental resolution and sensitivity required for the accurate measurement of the DCE cross sections at forward angles. However, the tiny values of such cross sections and the resolution requirements demand beam intensities much larger than those manageable with the present facility. The on-going upgrade of the INFN-LNS facilities in this perspective is part of the NUMEN project and will be discussed in the article.
Wide dynamic range acquisition system for innovative radiation detectors Petasecca, M.; Alpat, B.; Ambrosi, G. ...
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
05/2010, Letnik:
617, Številka:
1
Journal Article
Recenzirano
Odprti dostop
There is particular interest to develop low-noise and wide dynamic range data acquisition systems for silicon detectors in view of using the same acquisition readout electronics for a wide range of ...application fields like monitoring and characterization of radiation sources or particle beams. In the framework of a research project for the qualification of Components Off The Shelf (COTS) for their use in space, research groups from INFN-Perugia, INFN-LNS and from MAPRAD have developed a fully automated, remote controllable, wide dynamic range acquisition system for silicon strip or pixelated detectors. Its design and a basic description of the performance are given here.
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