•Measurement of 20Ne + 130Te double charge exchange reaction.•Nuclear reactions induced by heavy-ion accelerated beams as tools towards the determination of the double beta decay nuclear matrix ...elements.•NUMEN (NUclear Matrix Elements for Neutrinoless double beta decay) project at INFN – LNS.•Heavy-ion induced reactions with the MAGNEX magnetic spectrometer.
The 130Te(20Ne,20O)130Xe double charge exchange reaction was measured for the first time at very forward angles with the MAGNEX magnetic spectrometer at INFN-LNS. The study, performed at beam energy of 306 MeV, is part of a systematic exploration promoted by the NUMEN project. The last aims to measure specific reaction cross sections to provide experimentally driven information about nuclear matrix elements of interest in the context of neutrinoless double beta decay.
Thin films of C layers were deposited by radiofrequency magnetron sputtering on silicon substrates using three gaseous atmospheres: pure Ar, Ar+H2 and Ar+D2 mixtures. Scanning Electron Microscopy ...investigations showed that addition of D2 or H2 to main sputtering gas (Ar) leads to the enhancement of the deposition rate while the layer morphology remained columnar. Fourier Transform Infrared Spectroscopy measurements revealed the presence of D-C or H-C chemical bonds in the samples. Ion beam analysis measurements performed by simultaneous recording of the recoiled H and D ions, and of backscattered 4He confirmed the incorporation of hydrogen and deuterium in the deposited carbon thin films.
In this contribution we will present the future activities that our collaboration will carry out at ELI-NP (Extreme Light Infrastructure Nuclear Physics), the new multi peta-watt Laser facility, ...currently under construction at Bucharest (Romania). The activities concerns the study of nuclear reactions in laser plasmas. In this framework we proposed the construction of a new, general-purpose experimental set-up able to detect and identify neutrons and charged particles.
Carbon-carbon fusion reaction represents a nuclear process of great interest in astrophysics, since the carbon burning is connected with the third phase of massive stars (M > 8 M☉) evolution. In ...spite of several experimental works, carbon-carbon cross section has been measured at energy still above the Gamow window moreover data at low energy present big uncertainty. In this paper we report the results about the study of the 16O(12C,α20Ne)α reaction as a possible three-body process to investigate 12C(12C,α)20Ne at astrophysical energy via Trojan Horse Method (THM). This study represents the first step of a program of experiments aimed to measure the 12C+12C cross section at astrophysical energy using the THM.
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.
New experimental measurements of charge state distributions produced by a 20Ne10+ beam at 15 MeV/u colliding on various thin solid targets are presented. The use of the MAGNEX magnetic spectrometer ...enabled measurements of the 8+ charge state down to fractions of a few 10−5. The use of different post-stripper foils located downstream of the main target is explored, showing that low Z materials are particularly effective to shift the charge state distributions towards fully stripped conditions. The dependence on the foil thickness is also studied and discussed.
The experimental set-up working on the zero-degree beam-line of the 9MV Tandem Accelerator at IFIN-HH now offers a high accuracy and repeatability of the heavy ions nuclear physics experiments. This ...is achieved by an automated moving system, placed inside a circular reaction chamber, consisting of four moving arms covering a complete 360°. Each arm can hold one detector and is powered by a stepper motor having the possibility of micro-stepping up to 1/256 if the application requires, with a reduction gear box of 60:1 and a resolver acting as a witness for eventual position corrections. Moreover, the target support, positioned in the center of the chamber, is also assisted by a stepper motor and can rotate over 360° clockwise or counterclockwise. Two identical ΔE – E telescopes have received an upgrade in both the gas automated pressure and constant flow regulation by using a software implemented PID (Proportional-Integral-Derivative) controller.
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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
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Ca(
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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.
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