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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.
Beam dynamics simulation for the high intensity DAEδALUS cyclotrons Yang, J.J.; Adelmann, A.; Barletta, W. ...
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
03/2013, Letnik:
704
Journal Article
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In the DAEδALUS (Decay-At-rest Experiment for δCP studies At the Laboratory for Underground Science) project, high power H2+ cyclotron chains are proposed to efficiently provide proton beams with a ...kinetic energy of 800MeV and an average power in the MW range. Space charge plays a pivotal role in both the injector and the ring cyclotrons. Large-scale particle simulations show that the injector cyclotron is a space charge dominated cyclotron and that a 5mA beam current can be extracted with tolerable beam losses on the septum. In contrast, in the ring cyclotron, no space charge induced beam loss is observed during acceleration and extraction.
The Massachusetts Institute of Technology has been collaborating with the Laboratori Nazionali del Sud, Istituto Nazionale di Fisica Nucleare (INFN), in Catania, Sicily, on the conceptual design of a ...replacement magnet for the existing LNS cyclotron used by INFN. The existing magnet was built in the early 1980s. Future nuclear physics experiments require an upgrade of the superconducting cyclotron to increase the intensity of beams by a factor of 10-100. To achieve this goal, the extraction channel through the superconducting magnet needs to be larger than the present one in both the radial and axial directions. It is for these reasons that a new superconducting magnet fitting the new requirements must be built to replace the present one. Magnetic analyses succeeded in defining a coil set satisfying the specified field form factors. Several design options were considered, including a cryostable liquid-helium-pool-cooled design, as well as several epoxy impregnated (potted) designs. The potted and helium-pooled magnet design was developed at the conceptual level. The proposed design is viable and will be used as the baseline for the next stages of the design work.
The NUMEN experiment at INFN-LNS demands an upgrade of the Superconducting Cyclotron (CS) to deliver beam with power up to 10 kW for ions with mass A < 40 amu. To transport these high power beams, it ...is mandatory to build a new extraction beam line from the CS and to upgrade the existing beam transport lines to maintain the beam losses below 100 W, both in the accelerator room and along the beam transport areas. Moreover, a new fragment in-flight separator will be built to produce radioactive ion beams, but also to perform energy selection of the beam extracted from the cyclotron, to be delivered to the MAGNEX spectrometer with an energy spread below 0.1% FWHM. The use of a 10 kW ion beam implies also to redesign of the beam transport line inside the MAGNEX experimental room to allow the installation of a new large and well shielded beam dump beyond the apparatus.
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.
The Daeδalus experiment seeks to evaluate neutrino scattering effects that go beyond the standard model. Modular accelerators are employed to produce 800 MeV proton beams at the megawatt power level ...directed toward a target, producing neutrinos. The Superconducting Ring Cyclotron consists of identical sectors (currently 6) of superconducting dipole magnets with iron return frames. The Daeδalus Collaboration has produced a conceptual design for the magnet, which, after several iterations, is the current best design that achieves the physics requirements of the experiment. The main purpose of the analytical effort, results of which are presented here, is to develop a viable engineering design satisfying requirements to the superconductor, as well as structural and cryogenic requirements. The work includes proposed conceptual approaches, solid modeling and analyses for the conductor and winding pack design, high-temperature superconductor and copper current leads for the magnet, structural design of the magnet cold mass, cryostat and warm-to-cold supports, cryogenic design of the magnet cooling system, and magnet power supply sizing. A description of the winding pack design, structural analysis, and cryogenic system is reported.
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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