The goal of the NUMEN collaboration is the measurement of the cross sections of Double Charge Exchange reactions for several couple of ion projectile-target, in order to provide helpful data to study ...the nuclear matrix elements of the neutrino-less double β-decay. The need of big statistics and high precision in the measurements require the use of high intensity beams and very thin targets. This creates some problems to the design of the target frame and to the dissipation of the heat generated by the beam. The present paper reports a possible solution for the cooling system and the production technique of a tin target, together with the results of the preliminary tests of heat dissipation.
The FIRST experiment at GSI Pleskac, R.; Abou-Haidar, Z.; Agodi, C. ...
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
06/2012, Letnik:
678
Journal Article
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The FIRST (Fragmentation of Ions Relevant for Space and Therapy) experiment at the SIS accelerator of GSI laboratory in Darmstadt has been designed for the measurement of ion fragmentation ...cross-sections at different angles and energies between 100 and 1000MeV/nucleon. Nuclear fragmentation processes are relevant in several fields of basic research and applied physics and are of particular interest for tumor therapy and for space radiation protection applications.
The start of the scientific program of the FIRST experiment was on summer 2011 and was focused on the measurement of 400MeV/nucleon 12C beam fragmentation on thin (8mm) graphite target.
The detector is partly based on an already existing setup made of a dipole magnet (ALADiN), a time projection chamber (TP-MUSIC IV), a neutron detector (LAND) and a time of flight scintillator system (TOFWALL). This pre-existing setup has been integrated with newly designed detectors in the Interaction Region, around the carbon target placed in a sample changer. The new detectors are a scintillator Start Counter, a Beam Monitor drift chamber, a silicon Vertex Detector and a Proton Tagger scintillator system optimized for the detection of light fragments emitted at large angles.
In this paper we review the experimental setup, then we present the simulation software, the data acquisition system and finally the trigger strategy of the experiment.
Hadrontherapy treatments use charged particles (e.g. protons and carbon ions) to treat tumors. During a therapeutic treatment with carbon ions, the beam undergoes nuclear fragmentation processes ...giving rise to significant yields of secondary charged particles. An accurate prediction of these production rates is necessary to estimate precisely the dose deposited into the tumours and the surrounding healthy tissues. Nowadays, a limited set of double differential carbon fragmentation cross-section is available. Experimental data are necessary to benchmark Monte Carlo simulations for their use in hadrontherapy. The purpose of the FIRST experiment is to study nuclear fragmentation processes of ions with kinetic energy in the range from 100 to 1000MeV/u. Tracks are reconstructed using information from a pixel silicon detector based on the CMOS technology. The performances achieved using this device for hadrontherapy purpose are discussed. For each reconstruction step (clustering, tracking and vertexing), different methods are implemented. The algorithm performances and the accuracy on reconstructed observables are evaluated on the basis of simulated and experimental data.
The NUMEN project proposes to study heavy-ion induced Double Charge Exchange (DCE) reactions with the final goal to get information on the nuclear matrix elements for neutrinoless double beta (0νββ) ...decay. The knowledge of the nuclear matrix elements is crucial to infer the neutrino average masses from the possible measurement of the half-life of 0νββ decay. DCE reactions and 0νββ decay present some similarities, the initial and final-state wave functions are the same and the transition operators are similar. The experimental measurements of DCE reactions induced by heavy ions present a number of challenging aspects, since they are characterized by very low cross sections.
The case of the internal target for the hyper-nuclear experiment of the PANDA (antiproton Annihilation at Darmstadt) Collaboration at the High Energy Storage Ring of Facility for Antiproton and Ion ...Research is illustrated. After a discussion of the problems arising from the interaction of a solid internal target with an antiproton beam, the design of material, shape and sizes of a target satisfying the experimental requirements is presented. The techniques used to produce a prototype of this target are illustrated. Then the results of the tests performed on the prototype for investigating the properties (purity, radiation hardness, structure modifications after shaping) are reported and the plan of the future activity is pointed out.
A brief review of the double hypernuclei physics and state of the art of the todays available data is reported. The production of the prototype of diamond target is illustrated together with the ...tests to check its impurity level, the surface density, the radiation hardness and the phase modification. Finally the devised way to optimize the interaction between the bunch and the target, minimizing the detector damage, through the so-called “steering beam” technique is presented.
The goal of NUMEN project is to access experimentally driven information on Nuclear Matrix Elements (NME) involved in the neutrinoless double beta decay (0νββ), by high-accuracy measurements of the ...cross sections of Heavy Ion (HI) induced Double Charge Exchange (DCE) reactions. The knowledge of the nuclear matrix elements is crucial to infer the neutrino average masses from the possible measurement of the half-life of 00νββ decay and to compare experiments on different isotopes. In particular, the (
18
O,
18
Ne) and (
20
Ne,
20
O) reactions are performed as tools for β
+
β
+
and β
-
β
-
decays, respectively. The experiments are performed at INFN - Laboratory Nazionali del Sud (LNS) in Catania using the Superconducting Cyclotron (CS) to accelerate the beams and the MAGNEX magnetic spectrometer to detect the reaction products. The measured cross sections are very low, limiting the present exploration to few selected isotopes of interest in the context of typically low-yield experimental runs. In order to make feasible a systematic study of all the candidate nuclei, a major upgrade of the LNS facility is foreseen to increase the experimental yield of about two orders of magnitude. To this purpose, frontier technologies are going to be developed for both the accelerator and the detection systems. In parallel, advanced theoretical models will be developed to extract the nuclear structure information from the measured cross sections.
Within the NUMEN project, we present experimental issues and data reduction for the 116Cd(20Ne,20F)116In single charge exchange, 116Cd(20Ne,18O)118In two-proton transfer and 116Cd(20Ne,19F)117In ...one-proton transfer reactions at 15 AMeV incident energy.
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.
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